WorldWideScience

Sample records for ground-engaging drive wheels

  1. Full drive-by-wire dynamic control for four-wheel-steer all-wheel-drive vehicles

    Science.gov (United States)

    Fahimi, Farbod

    2013-03-01

    Most of the controllers introduced for four-wheel-steer (4WS) vehicles are derived with the assumption that the longitudinal speed of the vehicle is constant. However, in real applications, the longitudinal speed varies, and the longitudinal, lateral, and yaw dynamics are coupled. In this paper, the longitudinal dynamics of the vehicle as well as its lateral and yaw motions are controlled simultaneously. This way, the effect of driving/braking forces of the tires on the lateral and yaw motions of the vehicle are automatically included in the control laws. To address the dynamic parameter uncertainty of the vehicle, a chatter-free variable structure controller is introduced. Elimination of chatter is achieved by introducing a dynamically adaptive boundary layer thickness. It is shown via simulations that the proposed control approach performs more robustly than the controllers developed based on dynamic models, in which longitudinal speed is assumed to be constant, and only lateral speed and yaw rate are used as system states. Furthermore, this approach supports all-wheel-drive vehicles. Front-wheel-drive or rear-wheel-drive vehicles are also supported as special cases of an all-wheel-drive vehicle.

  2. Mechanical Design Engineering Enabler Project wheel and wheel drives

    Science.gov (United States)

    Nutt, Richard E.; Couch, Britt K.; Holley, John L., Jr.; Garris, Eric S.; Staut, Paul V.

    1992-01-01

    Our group was assigned the responsibility of designing the wheel and wheel drive system for a proof-of-concept model of the lunar-based ENABLER. ENABLER is a multi-purpose, six wheeled vehicle designed to lift and transport heavy objects associated with the construction of a lunar base. The resulting design was based on the performance criteria of the ENABLER. The drive system was designed to enable the vehicle to achieve a speed of 7 mph on a level surface, climb a 30 percent grade, and surpass a one meter high object and one meter wide crevice. The wheel assemblies were designed to support the entire weight of the vehicle on two wheels. The wheels were designed to serve as the main component of the vehicle's suspension and will provide suitable traction for lunar-type surfaces. The expected performance of the drive system for the ENABLER was influenced by many mechanical factors. The expected top speed on a level sandy surface is 4 mph instead of the desired 7 mph. This is due to a lack of necessary power at the wheels. The lack of power resulted from dimension considerations that allowed only an eight horsepower engine and also from mechanical inefficiencies of the hydraulic system. However, the vehicle will be able to climb a 30 percent grade, surpass a one meter high object and one meter wide crevice. The wheel assemblies will be able to support the entire weight of the vehicle on two wheels. The wheels will also provide adequate suspension for the vehicle and sufficient traction for lunar-type surfaces.

  3. Origami Wheel Transformer: A Variable-Diameter Wheel Drive Robot Using an Origami Structure.

    Science.gov (United States)

    Lee, Dae-Young; Kim, Sa-Reum; Kim, Ji-Suk; Park, Jae-Jun; Cho, Kyu-Jin

    2017-06-01

    A wheel drive mechanism is simple, stable, and efficient, but its mobility in unstructured terrain is seriously limited. Using a deformable wheel is one of the ways to increase the mobility of a wheel drive robot. By changing the radius of its wheels, the robot becomes able to pass over not only high steps but also narrow gaps. In this article, we propose a novel design for a variable-diameter wheel using an origami-based soft robotics design approach. By simply folding a patterned sheet into a wheel shape, a variable-diameter wheel was built without requiring lots of mechanical parts and a complex assembly process. The wheel's diameter can change from 30 to 68 mm, and it is light in weight at about 9.7 g. Although composed of soft materials (fabrics and films), the wheel can bear more than 400 times its weight. The robot was able to change the wheel's radius in response to terrain conditions, allowing it to pass over a 50-mm gap when the wheel is shrunk and a 50-mm step when the wheel is enlarged.

  4. Decoupling control of steering and driving system for in-wheel-motor-drive electric vehicle

    Science.gov (United States)

    Zhang, Han; Zhao, Wanzhong

    2018-02-01

    To improve the maneuverability and stability of in-wheel-motor-drive electric vehicle, a control strategy based on nonlinear decoupling control method is proposed in this paper, realizing the coordinated control of the steering and driving system. At first, the nonlinear models of the in-wheel-motor-drive electric vehicle and its sub-system are constructed. Then the inverse system decoupling theory is applied to decompose the nonlinear system into several independent subsystems, which makes it possible to realize the coordinated control of each subsystem. Next, the μ-Synthesis theory is applied to eliminate the influence of model uncertainty, improving the stability, robustness and tracking performance of in-wheel-motor-drive electric vehicle. Simulation and experiment results and numerical analyses, based on the electric vehicle actuated by in-wheel-motors, prove that the proposed control method is effective to accomplish the decoupling control of the steering and driving system in both simulation and real practice.

  5. General motors front wheel drive 2-mode hybrid transmission

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, James [General Motors Corp., Pontiac, MI (United States). New Transmission Products Group.; Holmes, Alan G. [General Motors Corp., Pontiac, MI (United States). Powertrain Hybrid Architecture

    2009-07-01

    General Motors now expands the application of two-mode hybrid technology to front wheel drive vehicles with the development of a hybrid electric transmission packaged into essentially the same space as a conventional automatic transmission for front wheel drive. This was accomplished using a space-efficient arrangement based on two planetary gear sets and electric motor-generators with large internal diameters. A combination of damper and hydraulically-controlled clutch allow comfortable shutdown and restarting of large-displacement engines in front wheel drive vehicles. The hybrid system delivers electric low-speed urban driving, two continuously variable ranges of transmission speed ratios, four fixed transmission speed ratios, electric acceleration boosting, and regenerative braking. In the first vehicle application, the two-mode hybrid helps to reduce vehicle fuel consumption by approximately one-third. (orig.)

  6. Two wheel speed robust sliding mode control for electric vehicle drive

    Directory of Open Access Journals (Sweden)

    Abdelfatah Nasri

    2008-01-01

    Full Text Available Nowadays the uses of electrical power resources are integrated in the modern vehicle motion traction chain so new technologies allow the development of electric vehicles (EV by means of static converters-related electric motors. All mechanical transmission devices are eliminated and vehicle wheel motion can be controlled by means of power electronics. The proposed propulsing system consists of two induction motors (IM that ensure the drive of the two back driving wheels. The proposed control structure-called independent machines- for speed control permit the achievement of an electronic differential. The electronic differential system ensures the robust control of the vehicle behavior on the road. It also allows controlling independently, every driving wheel to turn at different speeds in any curve. This paper presents the study and the sliding mode control strategy of the electric vehicle driving wheels.

  7. New Record Five-Wheel Drive, Spirit's Sol 1856

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical projection with geometric seam correction.

  8. Dynamic motion stabilization for front-wheel drive in-wheel motor electric vehicles

    Directory of Open Access Journals (Sweden)

    Jia-Sheng Hu

    2015-12-01

    Full Text Available This article presents a new dynamic motion stabilization approach to front-wheel drive in-wheel motor electric vehicles. The approach includes functions such as traction control system, electronic differential system, and electronic stability control. The presented electric vehicle was endowed with anti-skid performance in longitudinal accelerated start; smooth turning with less tire scrubbing; and safe driving experience in two-dimensional steering. The analysis of the presented system is given in numerical derivations. For practical verifications, this article employed a hands-on electric vehicle named Corsa-electric vehicle to carry out the tests. The presented approach contains an integrated scheme which can achieve the mentioned functions in a single microprocessor. The experimental results demonstrated the effectiveness and feasibility of the presented methodology.

  9. A novel dual motor drive system for three wheel electric vehicles

    Science.gov (United States)

    Panmuang, Piyapat; Thongsan, Taweesak; Suwapaet, Nuchida; Laohavanich, Juckamass; Photong, Chonlatee

    2018-03-01

    This paper presents a novel dual motor drive system used for three wheel electric vehicles that have one free wheel at the front and two wheels with a drive system at the end of the vehicles. A novel dual motor drive system consists of two identical DC motors that are independently controlled by its speed-torque controller. Under light load conditions, only one of the DC motors will operate around it rated whilst under hard load conditions both of the DC motors will operate. With this drive system, the motors will operate only at its high performance at rated or else no operate to retain longer lifetime. The simulated results for the Skylab three wheel electric vehicle prototype with 8kW at full load (high torque, low speed) and around 4kW at light/normal operating loads (regular speed-torque) showed that the proposed system provides better dynamic responses with faster overshoot current/voltage recovery time, has lower investment costs, has longer lifetime of the motors and allows the motors to always operate at their high performance and thus achieve more cost effective system compared to a single motor drive system with 8kW DC motors.

  10. Design of driving control strategy of torque distribution for two - wheel independent drive electric vehicle

    Science.gov (United States)

    Zhang, Chuanwei; Zhang, Dongsheng; Wen, Jianping

    2018-02-01

    In order to coordinately control the torque distribution of existing two-wheel independent drive electric vehicle, and improve the energy efficiency and control stability of the whole vehicle, the control strategies based on fuzzy control were designed which adopt the direct yaw moment control as the main line. For realizing the torque coordination simulation of the two-wheel independent drive vehicle, the vehicle model, motor model and tire model were built, including the vehicle 7 - DOF dynamics model, motion equation, torque equation. Finally, in the Carsim - Simulink joint simulation platform, the feasibility of the drive control strategy was verified.

  11. APPLIED PROBLEMS OF CURVILINEAR MOTION DYNAMICS OF ALL-WHEEL DRIVE TRACTION MEANS

    Directory of Open Access Journals (Sweden)

    G. S. Gorin

    2014-01-01

    Full Text Available Fundamental principles for hybrid theory on turning of an all-wheel drive system are given in the paper. The paper shows expediency of accounting longitudinal additional tangential reactions (parasitic forces in contacts of central and lateral wheels with foundation. Algorithms for calculating additional tangential reactions have been proposed in the paper. The paper presents calculation kinematics model for turning of steered and rigid bogie with inter-wheel differential at various axial drive.

  12. A Study of Torque Vectoring and Traction Control for an All-Wheel Drive Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Maharun Mui’nuddin

    2014-07-01

    Full Text Available Common vehicle always experience energy loss during cornering manoeuver. Thus, to ensure it did not happened especially at high speed, a study of torque vectoring and traction control need to be made since it can increase the traction control of tyres during cornering at high speed. The study of torque vectoring and traction control for an all-wheel drive electric vehicle was conducted by modelling an all-wheel drive electric vehicle (EV in ADAMS/Car software. In addition, an optimal control algorithm will be developed for best performance to minimize energy losses using MATLAB/Simulink software. Furthermore, to prove the effectiveness of the all-wheel drive electric, the torque and traction control simulation of the all-wheel drive electric vehicle will be compared with uncontrolled electric vehicle model. According to the result, torque vectoring and traction control of in-wheel motor in all wheel drive EV can help to increase the performance of the electric vehicle during cornering manoeuver. In conclusion, this study of torque vectoring and traction control for an all-wheel drive electric vehicle will help researchers to improve the design of the future electric vehicle in term of the vehicle performance during cornering manoeuvre.

  13. Position and force control of a vehicle with two or more steerable drive wheels

    Energy Technology Data Exchange (ETDEWEB)

    Reister, D.B.; Unseren, M.A.

    1992-10-01

    When a vehicle with two or more steerable drive wheels is traveling in a circle, the motion of the wheels is constrained. The wheel translational velocity divided by the radius to the center of rotation must be the same for all wheels. When the drive wheels are controlled independently using position control, the motion of the wheels may violate the constraints and the wheels may slip. Consequently, substantial errors can occur in the orientation of the vehicle. A vehicle with N drive wheels has (N - 1) constraints and one degree of freedom. We have developed a new approach to the control of a vehicle with N steerable drive wheels. The novel aspect of our approach is the use of force control. To control the vehicle, we have one degree of freedom for the position on the circle and (N - 1) forces that can be used to reduce errors. Recently, Kankaanranta and Koivo developed a control architecture that allows the force and position degrees of freedom to be decoupled. In the work of Kankaanranta and Koivo the force is an exogenous input. We have made the force endogenous by defining the force in terms of the errors in satisfying the rigid body kinematic constraints. We have applied the control architecture to the HERMIES-III robot and have measured a dramatic reduction in error (more than a factor of 20) compared to motions without force control.

  14. Elimination of torque pulsations in a direct drive EV wheel motor

    Energy Technology Data Exchange (ETDEWEB)

    Hredzak, B.; Gair, S. [Napier Univ., Edinburgh (United Kingdom); Eastham, J.F. [Univ. of Bath (United Kingdom)

    1996-09-01

    Double sided axial field machines are attractive for direct wheel drives in electric vehicles. This is due to the fact that stator/rotor misalignments can be accommodated. In this case the stator of the machine is envisaged mounted on the chassis of the car while the rotor directly drives the road wheel. Since the wheel is perturbed by the road surface the rotor will move vertically between the outside stator assemblies and thus give rise to torque pulsations. A vector control scheme has been implemented whereby the torque pulsations are eliminated by (i) calculation of the flux variation due to the rotor perturbation and (ii) using this signal for the modulation of the motor input current.

  15. Decrease in Ground-Run Distance of Small Airplanes by Applying Electrically-Driven Wheels

    Science.gov (United States)

    Kobayashi, Hiroshi; Nishizawa, Akira

    A new takeoff method for small airplanes was proposed. Ground-roll performance of an airplane driven by electrically-powered wheels was experimentally and computationally studied. The experiments verified that the ground-run distance was decreased by half with a combination of the powered driven wheels and propeller without increase of energy consumption during the ground-roll. The computational analysis showed the ground-run distance of the wheel-driven aircraft was independent of the motor power when the motor capability exceeded the friction between tires and ground. Furthermore, the distance was minimized when the angle of attack was set to the value so that the wing generated negative lift.

  16. Analysis of Wheel Hub Motor Drive Application in Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Sun Yuechao

    2017-01-01

    Full Text Available Based on the comparative analysis of the performance characteristics of centralized and distributed drive electric vehicles, we found that the wheel hub motor drive mode of the electric vehicles with distributed drive have compact structure, high utilization ratio of interior vehicle space, lower center of vehicle gravity, good driving stability, easy intelligent control and many other advantages, hence in line with the new requirements for the development of drive performance of electric vehicles, and distributed drive will be the ultimate mode of electric vehicles in the future.

  17. New Record Five-Wheel Drive, Spirit's Sol 1856 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11962 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11962 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  18. Creation of the Naturalistic Engagement in Secondary Tasks (NEST) distracted driving dataset.

    Science.gov (United States)

    Owens, Justin M; Angell, Linda; Hankey, Jonathan M; Foley, James; Ebe, Kazutoshi

    2015-09-01

    Distracted driving has become a topic of critical importance to driving safety research over the past several decades. Naturalistic driving data offer a unique opportunity to study how drivers engage with secondary tasks in real-world driving; however, the complexities involved with identifying and coding relevant epochs of naturalistic data have limited its accessibility to the general research community. This project was developed to help address this problem by creating an accessible dataset of driver behavior and situational factors observed during distraction-related safety-critical events and baseline driving epochs, using the Strategic Highway Research Program 2 (SHRP2) naturalistic dataset. The new NEST (Naturalistic Engagement in Secondary Tasks) dataset was created using crashes and near-crashes from the SHRP2 dataset that were identified as including secondary task engagement as a potential contributing factor. Data coding included frame-by-frame video analysis of secondary task and hands-on-wheel activity, as well as summary event information. In addition, information about each secondary task engagement within the trip prior to the crash/near-crash was coded at a higher level. Data were also coded for four baseline epochs and trips per safety-critical event. 1,180 events and baseline epochs were coded, and a dataset was constructed. The project team is currently working to determine the most useful way to allow broad public access to the dataset. We anticipate that the NEST dataset will be extraordinarily useful in allowing qualified researchers access to timely, real-world data concerning how drivers interact with secondary tasks during safety-critical events and baseline driving. The coded dataset developed for this project will allow future researchers to have access to detailed data on driver secondary task engagement in the real world. It will be useful for standalone research, as well as for integration with additional SHRP2 data to enable the

  19. Vehicle Dynamics Control of In-wheel Electric Motor Drive Vehicles Based on Averaging of Tire Force Usage

    Science.gov (United States)

    Masaki, Nobuo; Iwano, Haruo; Kamada, Takayoshi; Nagai, Masao

    For in-wheel electric motor drive vehicles, a new vehicle dynamics control which is based on the tire force usage rate is proposed. The new controller adopts non-linear optimal control could manage the interference between direct yaw-moment control and the tire force usage rate. The new control is considered total longitudinal and transverse tire force. Therefore the controller can prevent tire force saturation near tire force limit during cornering. Simulations and test runs by the custom made four wheel drive in-wheel motor electric vehicle show that higher driving stability performance compared to the performance of the same vehicle without control.

  20. Reducing Energy Demand Using Wheel-Individual Electric Drives to Substitute EPS-Systems

    Directory of Open Access Journals (Sweden)

    Jürgen Römer

    2018-01-01

    Full Text Available The energy demand of vehicles is influenced, not only by the drive systems, but also by a number of add-on systems. Electric vehicles must satisfy this energy demand completely from the battery. Hence, the use of power steering systems directly result in a range reduction. The “e2-Lenk” joint project funded by the German Federal Ministry of Education and Research (BMBF involves a novel steering concept for electric vehicles to integrate the function of steering assistance into the drive-train. Specific distribution of driving torque at the steered axle allows the steering wheel torque to be influenced to support the steering force. This provides a potential for complete substitution of conventional power steering systems and reduces the vehicle’s energy demand. This paper shows the potential of wheel-individual drives influencing the driver’s steering torque using a control technique based on classical EPS control plans. Compared to conventional power-assisted steering systems, a reduced energy demand becomes evident over a wide range of operating conditions.

  1. Aerodynamic analysis of an isolated vehicle wheel

    Science.gov (United States)

    Leśniewicz, P.; Kulak, M.; Karczewski, M.

    2014-08-01

    Increasing fuel prices force the manufacturers to look into all aspects of car aerodynamics including wheels, tyres and rims in order to minimize their drag. By diminishing the aerodynamic drag of vehicle the fuel consumption will decrease, while driving safety and comfort will improve. In order to properly illustrate the impact of a rotating wheel aerodynamics on the car body, precise analysis of an isolated wheel should be performed beforehand. In order to represent wheel rotation in contact with the ground, presented CFD simulations included Moving Wall boundary as well as Multiple Reference Frame should be performed. Sliding mesh approach is favoured but too costly at the moment. Global and local flow quantities obtained during simulations were compared to an experiment in order to assess the validity of the numerical model. Results of investigation illustrates dependency between type of simulation and coefficients (drag and lift). MRF approach proved to be a better solution giving result closer to experiment. Investigation of the model with contact area between the wheel and the ground helps to illustrate the impact of rotating wheel aerodynamics on the car body.

  2. Aerodynamic analysis of an isolated vehicle wheel

    International Nuclear Information System (INIS)

    Leśniewicz, P; Kulak, M; Karczewski, M

    2014-01-01

    Increasing fuel prices force the manufacturers to look into all aspects of car aerodynamics including wheels, tyres and rims in order to minimize their drag. By diminishing the aerodynamic drag of vehicle the fuel consumption will decrease, while driving safety and comfort will improve. In order to properly illustrate the impact of a rotating wheel aerodynamics on the car body, precise analysis of an isolated wheel should be performed beforehand. In order to represent wheel rotation in contact with the ground, presented CFD simulations included Moving Wall boundary as well as Multiple Reference Frame should be performed. Sliding mesh approach is favoured but too costly at the moment. Global and local flow quantities obtained during simulations were compared to an experiment in order to assess the validity of the numerical model. Results of investigation illustrates dependency between type of simulation and coefficients (drag and lift). MRF approach proved to be a better solution giving result closer to experiment. Investigation of the model with contact area between the wheel and the ground helps to illustrate the impact of rotating wheel aerodynamics on the car body.

  3. Design of an Axial-Flux permanent magnet machine for an in-wheel direct drive application

    NARCIS (Netherlands)

    Bastiaens, K.; Jansen, J.W.; Jumayev, S.; Lomonova, E.A.

    2017-01-01

    This paper concerns the optimization and comparison of six different axial-flux permanent magnet (AFPM) machine topologies for an in-wheel direct drive application. The objective of the optimization is to reach maximum power density, which is of essence for an in-wheel motor. The machine topologies

  4. Single-wheel drive with new electric components. Einzelradantrieb mit neuen E-Komponenten

    Energy Technology Data Exchange (ETDEWEB)

    Westendorf, H. (Fichtel und Sachs AG, Schweinfurt (Germany)); Schiebold, S. (Fichtel und Sachs AG, Schweinfurt (Germany)); Ehrhart, P. (Fichtel und Sachs AG, Schweinfurt (Germany)); Lindner, L. (Fichtel und Sachs AG, Schweinfurt (Germany))

    1991-01-01

    Fundamentally important developments and innovations in the fields of magnetic materials, plastics technology and electronics, together with new control concepts, make a new drive concept possible for passenger cars produced in series. The concept, which makes use of a combustion engine and an all-electric power transmission with a single-wheel drive, is presented, together with its components. (orig./HW)

  5. Frequency and time domain characteristics of digital control of electric vehicle in-wheel drives

    Directory of Open Access Journals (Sweden)

    Jarzebowicz Leszek

    2017-12-01

    Full Text Available In-wheel electric drives are promising as actuators in active safety systems of electric and hybrid vehicles. This new function requires dedicated control algorithms, making it essential to deliver models that reflect better the wheel-torque control dynamics of electric drives. The timing of digital control events, whose importance is stressed in current research, still lacks an analytical description allowing for modeling its influence on control system dynamics. In this paper, authors investigate and compare approaches to the analog and discrete analytical modeling of torque control loop in digitally controlled electric drive. Five different analytical models of stator current torque component control are compared to judge their accuracy in representing drive control dynamics related to the timing of digital control events. The Bode characteristics and stepresponse characteristics of the analytical models are then compared with those of a reference model for three commonly used cases of motor discrete control schemes. Finally, the applicability of the presented models is discussed.

  6. Wheeled Vehicle Drive Lines, Axles, and Suspension Systems. Military Curriculum Materials for Vocational and Technical Education.

    Science.gov (United States)

    Army Ordnance Center and School, Aberdeen Proving Ground, MD.

    This course is one of several subcourses that make up the entire Army correspondence course on wheeled vehicle maintenance. The subcourse is designed to provide the student with information about the operation, malfunction diagnosis, maintenance, and repair of wheeled vehicle drive lines, axles, and suspension systems. It provides the basic…

  7. Haulage trucks model with four electric separate wheel drives

    Directory of Open Access Journals (Sweden)

    R. Setlak

    2005-02-01

    Full Text Available This article contains a course of work of the construction of a vehicle model that has four electrical motors built into each wheel. During the project two models of a vehicle were constructed. A microprocessor based control system has also been designed and built. A vehicle is controlled by a steering unit which contains a steering wheel with a force feedback system, push buttons, an accelerator and a brake. The connection between a steering unit and a model is realized by interface RS-485. The driving motors are dc motors with permanent magnets. Power supply consists of an acid battery located in the vehicle. The vehicle control system is divided into two parts. The first part is built into the vehicle and operates as a vehicle main control system and the second is built into a steering unit and operates as the main control steering system.

  8. Three omni-directional wheels control on a mobile robot

    OpenAIRE

    Ribeiro, António Fernando; Moutinho, Ivo; Silva, Pedro; Fraga, Carlos; Pereira, Nino

    2004-01-01

    Traditional two wheels differential drive normally used on mobile robots have manoeuvrability limitations and take time to sort out. Most teams use two driving wheels (with one or two cast wheels), four driving wheels and even three driving wheels. A three wheel drive with omni-directional wheel has been tried with success, and was implemented on fast moving autonomous mobile robots. This paper deals with the mathematical kinematics description of such mobile platform, it describes the advant...

  9. Driving in Parkinson's disease: mobility, accidents, and sudden onset of sleep at the wheel.

    Science.gov (United States)

    Meindorfner, Charlotte; Körner, Yvonne; Möller, Jens Carsten; Stiasny-Kolster, Karin; Oertel, Wolfgang Hermann; Krüger, Hans-Peter

    2005-07-01

    Only few studies have addressed driving ability in Parkinson's disease (PD) to date. However, studies investigating accident proneness of PD patients are urgently needed in the light of motor disability in PD and--particularly--the report of "sleep attacks" at the wheel. We sent a questionnaire about sudden onset of sleep (SOS) and driving behavior to 12,000 PD patients. Subsequently, of 6,620 complete data sets, 361 patients were interviewed by phone. A total of 82% of those 6,620 patients held a driving license, and 60% of them still participated in traffic. Of the patients holding a driving license, 15% had been involved in and 11% had caused at least one accident during the past 5 years. The risk of causing accidents was significantly increased for patients who felt moderately impaired by PD, had an increased Epworth Sleepiness Scale (ESS) score, and had experienced SOS while driving. Sleep attacks at the wheel usually occurred in easy driving situations and resulted in typical fatigue-related accidents. Those having retired from driving had a more advanced (subjective) disease severity, higher age, more frequently female gender, an increased ESS score, and a longer disease duration. The study revealed SOS and daytime sleepiness as critical factors for traffic safety in addition to motor disabilities of PD patients. The results suggest that real sleep attacks without any prior sleepiness are rare. However, our data underline the importance of mobility for patients and the need for further studies addressing the ability to drive in PD. Copyright 2005 Movement Disorder Society.

  10. A fuzzy logic sliding mode controlled electronic differential for a direct wheel drive EV

    Science.gov (United States)

    Ozkop, Emre; Altas, Ismail H.; Okumus, H. Ibrahim; Sharaf, Adel M.

    2015-11-01

    In this study, a direct wheel drive electric vehicle based on an electronic differential system with a fuzzy logic sliding mode controller (FLSMC) is studied. The conventional sliding surface is modified using a fuzzy rule base to obtain fuzzy dynamic sliding surfaces by changing its slopes using the global error and its derivative in a fuzzy logic inference system. The controller is compared with proportional-integral-derivative (PID) and sliding mode controllers (SMCs), which are usually preferred to be used in industry. The proposed controller provides robustness and flexibility to direct wheel drive electric vehicles. The fuzzy logic sliding mode controller, electronic differential system and the overall electrical vehicle mechanism are modelled and digitally simulated by using the Matlab software. Simulation results show that the system with FLSMC has better efficiency and performance compared to those of PID and SMCs.

  11. Design and implementation of a personal mobility of single spherical drive

    International Nuclear Information System (INIS)

    Hoshino, Tasuku; Yazawa, Miki; Naganuma, Ryota; Takada, Kotaro

    2016-01-01

    This paper deals with a personal electric vehicle driven by a single spherical wheel. Using an appropriate feedback control, this driving strategy realizes dynamic stability in all directions and the vehicle can always be kept upright on the road surface of variety of slopes. It also enables immediate mobility to all directions, unlike personal vehicles of two- wheel type. The spherical wheel is driven by omnidirectional wheels as usual; however, since the number and location of wheels have huge effect on the driving performance, the authors firstly analyze kinematics of omnidirectional wheels and sphere and derive new configuration to achieve maximum power. Based on the kinematic analysis, the equation of motion of the vehicle is derived via Lagrangian formulation. The full dynamic model including kinematic constraints is then derived. Using the full model, a stabilizing controller for driving is designed based on partial feedback linearization technique. The vehicle is constructed and tested with a human driver. The proposed configuration of omnidirectional wheels, the controller design model and the control scheme are examined in practice. Results of the experiments, including going over uphill road and uneven ground, show much better driving performance than authors’ previous prototype of the similar. (paper)

  12. Open-wheel race car driving: energy cost for pilots.

    Science.gov (United States)

    Beaune, Bruno; Durand, Sylvain; Mariot, Jean-Pierre

    2010-11-01

    The aim of this study was to evaluate the energy cost of speedway open-wheel race car driving using actimetry. Eight pilot students participated in a training session consisting of 5 successive bouts of around 30 minutes driving at steady speed on the Bugatti speedway of Le Mans (France). Energy expenditure (EE, kcal) was determined continuously by the actimetric method using the standard equation. Energy cost was estimated through physical activity ratio (PAR = EE/BMR ratio, Mets) calculation after basal metabolism rate (BMR, kcal·min-1) estimation. A 1-met PAR value was attributed to the individual BMR of each volunteer. Bout durations and EE were not significantly different between driving bouts. Mean speed was 139.94 ± 2.96 km·h-1. Physical activity ratio values ranged 4.92 ± 0.50 to 5.43 ± 0.47 Mets, corresponding to a 5.27 ± 0.47-Mets mean PAR values and a 1.21 ± 0.41 kcal·min-1 mean BMR value. These results suggest that actimetry is a simple and efficient method for EE and PAR measurements in motor sports. However, further studies are needed in the future to accurately evaluate relationships between PAR and driving intensity or between PAR and race car type.

  13. Development of a Cooperative Braking System for Front-Wheel Drive Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Di Zhao

    2018-02-01

    Full Text Available Most electric vehicles adopt cooperative braking systems that can blend friction braking torque with regenerative braking torque to achieve higher energy efficiency while maintaining a certain braking performance and driving safety. This paper presented a new cooperative regenerative braking system that contained a fully-decoupled hydraulic braking mechanism based on a modified electric stability control system. The pressure control algorithm and brake force distribution strategy were also discussed. Dynamic models of a front wheel drive electric car equipped with this system and a simulation platform with a driver model and driving cycles were established. Tests to evaluate the braking performance and energy regeneration were simulated and analyzed on this platform and the simulation results showed the feasibility and effectiveness of this system.

  14. Design and analysis of new fault-tolerant permanent magnet motors for four-wheel-driving electric vehicles

    Science.gov (United States)

    Liu, Guohai; Gong, Wensheng; Chen, Qian; Jian, Linni; Shen, Yue; Zhao, Wenxiang

    2012-04-01

    In this paper, a novel in-wheel permanent-magnet (PM) motor for four-wheel-driving electrical vehicles is proposed. It adopts an outer-rotor topology, which can help generate a large drive torque, in order to achieve prominent dynamic performance of the vehicle. Moreover, by adopting single-layer concentrated-windings, fault-tolerant teeth, and the optimal combination of slot and pole numbers, the proposed motor inherently offers negligible electromagnetic coupling between different phase windings, hence, it possesses a fault-tolerant characteristic. Meanwhile, the phase back electromotive force waveforms can be designed to be sinusoidal by employing PMs with a trapezoidal shape, eccentric armature teeth, and unequal tooth widths. The electromagnetic performance is comprehensively investigated and the optimal design is conducted by using the finite-element method.

  15. Optimal control of mode transition for four-wheel-drive hybrid electric vehicle with dry dual-clutch transmission

    Science.gov (United States)

    Zhao, Zhiguo; Lei, Dan; Chen, Jiayi; Li, Hangyu

    2018-05-01

    When the four-wheel-drive hybrid electric vehicle (HEV) equipped with a dry dual clutch transmission (DCT) is in the mode transition process from pure electrical rear wheel drive to front wheel drive with engine or hybrid drive, the problem of vehicle longitudinal jerk is prominent. A mode transition robust control algorithm which resists external disturbance and model parameter fluctuation has been developed, by taking full advantage of fast and accurate torque (or speed) response of three electrical power sources and getting the clutch of DCT fully involved in the mode transition process. Firstly, models of key components of driveline system have been established, and the model of five-degrees-of-freedom vehicle longitudinal dynamics has been built by using a Uni-Tire model. Next, a multistage optimal control method has been produced to realize the decision of engine torque and clutch-transmitted torque. The sliding-mode control strategy for measurable disturbance has been proposed at the stage of engine speed dragged up. Meanwhile, the double tracking control architecture that integrates the model calculating feedforward control with H∞ robust feedback control has been presented at the stage of speed synchronization. Finally, the results from Matlab/Simulink software and hardware-in-the-loop test both demonstrate that the proposed control strategy for mode transition can not only coordinate the torque among different power sources and clutch while minimizing vehicle longitudinal jerk, but also provide strong robustness to model uncertainties and external disturbance.

  16. Differential Control Strategy based on an Equal Slip Rate for an All-wheel Electricdrive Underground Articulated Dumping Truck

    Directory of Open Access Journals (Sweden)

    Jin Chun

    2014-09-01

    Full Text Available A differential control strategy based on equal slip rates is introduced to improve the steering stability of an all-wheelelectric-drive underground articulated dumping truck. Steering kinematic and dynamic models of the truck are derived to describe the movement relationship and force of the driving wheels. In consideration of the difficulty of obtaining the absolute velocity for an all-wheel-drive truck, an acceleration sensor was set on a test truck, and a kalman filter was applied to obtain the actual value for the truck body. Simulation results for an equal-slip control strategy were compared with experimental results for an equal-torque control strategy. In the simulation, the four-wheel slip rate was 0.08 and the steering system of the truck was stable. The results verify that the equal-slip control strategy makes better use of the ground adhesion coefficient, is able to reasonably distribute drive power, notably reduces tire wear, and improves the use of driving power.

  17. Evaluation of Rutting Performance of Asphalt Mixture with Driving Wheel Pavement Analyzer

    Directory of Open Access Journals (Sweden)

    Xu Cai

    2017-01-01

    Full Text Available Rutting is common pavement distress, which leads to lower riding comfort for road users and high maintenance costs. One of the commonly used tests is the simulation test with wheel tracking devices. Here, a new rutting test system has been developed based on the “Driving Wheel Pavement Analyzer” (DWPA to evaluate the rutting performance of asphalt mixtures. This study conducted three types of rutting tests to validate feasibility, reliability, and accuracy of DWPA test. The results indicated that the DWPA test provided more information on ruts and enabled us to distinguish the performance of materials. The CDWPA index is better suited to reflect the rutting resistance of the material, which is highly correlated to the APA rutting index and the rutting test index of China according to the grey relational analysis results.

  18. Prevalence of sleepiness while driving four-wheel motor vehicles in Fiji: a population-based survey (TRIP 9).

    Science.gov (United States)

    Herman, Josephine; Ameratunga, Shanthi N; Wainiqolo, Iris; Kafoa, Berlin; Robinson, Elizabeth; McCaig, Eddie; Jackson, Rod

    2013-08-01

    Sleepiness has been shown to be a risk factor for road crashes in high-income countries, but has received little attention in low- and middle-income countries. We examined the prevalence of sleepiness and sleep-related disorders among drivers of four-wheel motor vehicles in Fiji. Using a two-stage cluster sampling roadside survey conducted over 12 months, we recruited a representative sample of people driving four-wheel motor vehicles on the island of Viti Levu, Fiji. A structured interviewer-administered questionnaire sought self-report information on driver characteristics including sleep-related measures. The 752 motor vehicle drivers recruited (84% response rate) were aged 17-75 years, with most driving in Viti Levu undertaken by male subjects (93%), and those identifying with Indian (70%) and Fijian (22%) ethnic groups. Drivers who reported that they were not fully alert accounted for 17% of driving, while a further 1% of driving was undertaken by those who reported having difficulty staying awake or feeling sleepy. A quarter of the driving time among 15-24-year-olds included driving while sleepy or not fully alert, with a similar proportion driving while chronically sleep deprived (ie, with less than five nights of adequate sleep in the previous week=27%). Driving while acutely or chronically sleep deprived was generally more common among Fijians compared with Indians. Driving while not fully alert is relatively common in Fiji. Sleepiness while driving may be an important contributor to road traffic injuries in this and other low- and middle-income countries.

  19. Mobility potential of a robotic six-wheeled omnidirectional drive vehicle (ODV) with z-axis and tire inflation control

    Science.gov (United States)

    Witus, Gary

    2000-07-01

    Robot vehicle mobility is the product of the physical configuration, mechatronics (sensors, actuators, and control) and the motion programs for different obstacles, terrain conditions, and maneuver objectives. This paper examines the mobility potential of a robotic 6-by-6 wheeled omni-directional drive vehicle (ODV) with z-axis and tire inflation control. Ad ODV can steer and drive all wheels independently. The direction of motion is independent of the orientation of the body. Z- axis control refers to independent control of the suspension elevation at each wheel. Pneumatic tire inflation control provides the ability to inflate and deflate individual tires. The paper describes motion programs for various discrete obstacles and challenging terrain conditions. The paper illustrates how ODV control, z-axis control and tire inflation control interact to provide high mobility with respect to cornering, maneuvering on slopes, negotiating vertical step and horizontal gap obstacles, and braking/acceleration on soft soil and slick surfaces. The paper derives guidelines for the physical dimensions of the vehicle needed to achieve these capabilities.

  20. Umbrella Wheel - a stair-climbing and obstacle-handling wheel design concept

    DEFF Research Database (Denmark)

    Iversen, Simon; Jouffroy, Jerome

    2017-01-01

    This paper proposes a new design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change of configurat......This paper proposes a new design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change...... of configuration, staircases with a wide range of dimensions can be covered efficiently and safely. The design, named Umbrella Wheel, can consist of as many wheel segments as desired, and as few as two. A smaller or higher number of wheel segments has advantages and disadvantages depending on the specific...

  1. Age differences in the takeover of vehicle control and engagement in non-driving-related activities in simulated driving with conditional automation.

    Science.gov (United States)

    Clark, Hallie; Feng, Jing

    2017-09-01

    High-level vehicle automation has been proposed as a valuable means to enhance the mobility of older drivers, as older drivers experience age-related declines in many cognitive functions that are vital for safe driving. Recent research attempted to examine age differences in how engagement in non-driving-related activities impact driving performance, by instructing drivers to engage in mandatory pre-designed activities. While the mandatory engagement method allows a precise control of the timing and mental workload of the non-driving-related activities, it is different from how a driver would naturally engage in these activities. This study allowed younger (age 18-35, mean age=19.9years) and older drivers (age 62-81, mean age=70.4years) to freely decide when and how to engage in voluntarily chosen non-driving-related activities during simulated driving with conditional automation. We coded video recordings of participants' engagement in non-driving-related activities. We examined the effect of age, level of activity-engagement and takeover notification interval on vehicle control performance during the takeover, by comparing between the high and low engagement groups in younger and older drivers, across two takeover notification interval conditions. We found that both younger and older drivers engaged in various non-driving-related activities during the automated driving portion, with distinct preferences on the type of activity for each age group (i.e., while younger drivers mostly used an electronic device, older drivers tended to converse). There were also significant differences between the two age groups and between the two notification intervals on various driving performance measures. Older drivers benefited more than younger drivers from the longer interval in terms of response time to notifications. Voluntary engagement in non-driving-related activities did not impair takeover performance in general, although there was a trend of older drivers who were

  2. Development of New Wheel-Chair for Sports Competition

    Directory of Open Access Journals (Sweden)

    Akira Shionoya

    2018-03-01

    Full Text Available The purpose of this study was to develop the new wheel-chair which had the function to drive straight by one-hand operation. To perform this purpose, the driving force transmission axis (DFTA which had transmitted the driving force from the one side of wheel to another side of that was developed. The wheel-chair could drive straight by one-hand operation by the DFTA. The large torque, however, was generated in the DFTA, because the DFTA transmitted the driving force from the one side of wheel to another side by the axis of small diameter. Furthermore, the shear stress in the DFTA generated by this torque would lead to the DFTA break. The shear stress in the DFTA was calculated to examine the axial strength and durability. On the DETA of the wheelchair, the maximum shear stress calculated from the torque in driving was 39.53 MP and this was defined as the standard of the demand specifications as a strength and durability of the DFTA.

  3. Integrated Fault Diagnosis Algorithm for Motor Sensors of In-Wheel Independent Drive Electric Vehicles

    Science.gov (United States)

    Jeon, Namju; Lee, Hyeongcheol

    2016-01-01

    An integrated fault-diagnosis algorithm for a motor sensor of in-wheel independent drive electric vehicles is presented. This paper proposes a method that integrates the high- and low-level fault diagnoses to improve the robustness and performance of the system. For the high-level fault diagnosis of vehicle dynamics, a planar two-track non-linear model is first selected, and the longitudinal and lateral forces are calculated. To ensure redundancy of the system, correlation between the sensor and residual in the vehicle dynamics is analyzed to detect and separate the fault of the drive motor system of each wheel. To diagnose the motor system for low-level faults, the state equation of an interior permanent magnet synchronous motor is developed, and a parity equation is used to diagnose the fault of the electric current and position sensors. The validity of the high-level fault-diagnosis algorithm is verified using Carsim and Matlab/Simulink co-simulation. The low-level fault diagnosis is verified through Matlab/Simulink simulation and experiments. Finally, according to the residuals of the high- and low-level fault diagnoses, fault-detection flags are defined. On the basis of this information, an integrated fault-diagnosis strategy is proposed. PMID:27973431

  4. Integrated Fault Diagnosis Algorithm for Motor Sensors of In-Wheel Independent Drive Electric Vehicles.

    Science.gov (United States)

    Jeon, Namju; Lee, Hyeongcheol

    2016-12-12

    An integrated fault-diagnosis algorithm for a motor sensor of in-wheel independent drive electric vehicles is presented. This paper proposes a method that integrates the high- and low-level fault diagnoses to improve the robustness and performance of the system. For the high-level fault diagnosis of vehicle dynamics, a planar two-track non-linear model is first selected, and the longitudinal and lateral forces are calculated. To ensure redundancy of the system, correlation between the sensor and residual in the vehicle dynamics is analyzed to detect and separate the fault of the drive motor system of each wheel. To diagnose the motor system for low-level faults, the state equation of an interior permanent magnet synchronous motor is developed, and a parity equation is used to diagnose the fault of the electric current and position sensors. The validity of the high-level fault-diagnosis algorithm is verified using Carsim and Matlab/Simulink co-simulation. The low-level fault diagnosis is verified through Matlab/Simulink simulation and experiments. Finally, according to the residuals of the high- and low-level fault diagnoses, fault-detection flags are defined. On the basis of this information, an integrated fault-diagnosis strategy is proposed.

  5. Wheel speed management control system for spacecraft

    Science.gov (United States)

    Goodzeit, Neil E. (Inventor); Linder, David M. (Inventor)

    1991-01-01

    A spacecraft attitude control system uses at least four reaction wheels. In order to minimize reaction wheel speed and therefore power, a wheel speed management system is provided. The management system monitors the wheel speeds and generates a wheel speed error vector. The error vector is integrated, and the error vector and its integral are combined to form a correction vector. The correction vector is summed with the attitude control torque command signals for driving the reaction wheels.

  6. Aerodynamic Drag Analysis of 3-DOF Flex-Gimbal GyroWheel System in the Sense of Ground Test

    Science.gov (United States)

    Huo, Xin; Feng, Sizhao; Liu, Kangzhi; Wang, Libin; Chen, Weishan

    2016-01-01

    GyroWheel is an innovative device that combines the actuating capabilities of a control moment gyro with the rate sensing capabilities of a tuned rotor gyro by using a spinning flex-gimbal system. However, in the process of the ground test, the existence of aerodynamic disturbance is inevitable, which hinders the improvement of the specification performance and control accuracy. A vacuum tank test is a possible candidate but is sometimes unrealistic due to the substantial increase in costs and complexity involved. In this paper, the aerodynamic drag problem with respect to the 3-DOF flex-gimbal GyroWheel system is investigated by simulation analysis and experimental verification. Concretely, the angular momentum envelope property of the spinning rotor system is studied and its integral dynamical model is deduced based on the physical configuration of the GyroWheel system with an appropriately defined coordinate system. In the sequel, the fluid numerical model is established and the model geometries are checked with FLUENT software. According to the diversity and time-varying properties of the rotor motions in three-dimensions, the airflow field around the GyroWheel rotor is analyzed by simulation with respect to its varying angular velocity and tilt angle. The IPC-based experimental platform is introduced, and the properties of aerodynamic drag in the ground test condition are obtained through comparing the simulation with experimental results. PMID:27941602

  7. Implications of driving patterns on well-to-wheel performance of plug-in hybrid electric vehicles.

    Science.gov (United States)

    Raykin, Leon; MacLean, Heather L; Roorda, Matthew J

    2012-06-05

    This study examines how driving patterns (distance and conditions) and the electricity generation supply interact to impact well-to-wheel (WTW) energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW performance of a PHEV is compared with that of a similar (nonplug-in) gasoline hybrid electric vehicle and internal combustion engine vehicle (ICEV). Driving PHEVs for short distances between recharging generally results in lower WTW total and fossil energy use and GHG emissions per kilometer compared to driving long distances, but the extent of the reductions depends on the electricity supply. For example, the shortest driving pattern in this study with hydroelectricity uses 81% less fossil energy than the longest driving pattern. However, the shortest driving pattern with coal-based electricity uses only 28% less fossil energy. Similar trends are observed in reductions relative to the nonplug-in vehicles. Irrespective of the electricity supply, PHEVs result in greater reductions in WTW energy use and GHG emissions relative to ICEVs for city than highway driving conditions. PHEVs charging from coal facilities only reduce WTW energy use and GHG emissions relative to ICEVs for certain favorable driving conditions. The study results have implications for environmentally beneficial PHEV adoption and usage patterns.

  8. Model based Fault Detection and Isolation for Driving Motors of a Ground Vehicle

    Directory of Open Access Journals (Sweden)

    Young-Joon Kim

    2016-04-01

    Full Text Available This paper proposes model based current sensor and position sensor fault detection and isolation algorithm for driving motor of In-wheel independent drive electric vehicle. From low level perspective, fault diagnosis conducted and analyzed to enhance robustness and stability. Composing state equation of interior permanent magnet synchronous motor (IPMSM, current sensor fault and position sensor fault diagnosed with parity equation. Validation and usefulness of algorithm confirmed based on IPMSM fault occurrence simulation data.

  9. Estimation of Longitudinal Force and Sideslip Angle for Intelligent Four-Wheel Independent Drive Electric Vehicles by Observer Iteration and Information Fusion.

    Science.gov (United States)

    Chen, Te; Chen, Long; Xu, Xing; Cai, Yingfeng; Jiang, Haobin; Sun, Xiaoqiang

    2018-04-20

    Exact estimation of longitudinal force and sideslip angle is important for lateral stability and path-following control of four-wheel independent driven electric vehicle. This paper presents an effective method for longitudinal force and sideslip angle estimation by observer iteration and information fusion for four-wheel independent drive electric vehicles. The electric driving wheel model is introduced into the vehicle modeling process and used for longitudinal force estimation, the longitudinal force reconstruction equation is obtained via model decoupling, the a Luenberger observer and high-order sliding mode observer are united for longitudinal force observer design, and the Kalman filter is applied to restrain the influence of noise. Via the estimated longitudinal force, an estimation strategy is then proposed based on observer iteration and information fusion, in which the Luenberger observer is applied to achieve the transcendental estimation utilizing less sensor measurements, the extended Kalman filter is used for a posteriori estimation with higher accuracy, and a fuzzy weight controller is used to enhance the adaptive ability of observer system. Simulations and experiments are carried out, and the effectiveness of proposed estimation method is verified.

  10. Driving context influences drivers' decision to engage in visual-manual phone tasks: Evidence from a naturalistic driving study.

    Science.gov (United States)

    Tivesten, Emma; Dozza, Marco

    2015-06-01

    Visual-manual (VM) phone tasks (i.e., texting, dialing, reading) are associated with an increased crash/near-crash risk. This study investigated how the driving context influences drivers' decisions to engage in VM phone tasks in naturalistic driving. Video-recordings of 1,432 car trips were viewed to identify VM phone tasks and passenger presence. Video, vehicle signals, and map data were used to classify driving context (i.e., curvature, other vehicles) before and during the VM phone tasks (N=374). Vehicle signals (i.e., speed, yaw rate, forward radar) were available for all driving. VM phone tasks were more likely to be initiated while standing still, and less likely while driving at high speeds, or when a passenger was present. Lead vehicle presence did not influence how likely it was that a VM phone task was initiated, but the drivers adjusted their task timing to situations when the lead vehicle was increasing speed, resulting in increasing time headway. The drivers adjusted task timing until after making sharp turns and lane change maneuvers. In contrast to previous driving simulator studies, there was no evidence of drivers reducing speed as a consequence of VM phone task engagement. The results show that experienced drivers use information about current and upcoming driving context to decide when to engage in VM phone tasks. However, drivers may fail to sufficiently increase safety margins to allow time to respond to possible unpredictable events (e.g., lead vehicle braking). Advanced driver assistance systems should facilitate and possibly boost drivers' self-regulating behavior. For instance, they might recognize when appropriate adaptive behavior is missing and advise or alert accordingly. The results from this study could also inspire training programs for novice drivers, or locally classify roads in terms of the risk associated with secondary task engagement while driving. Copyright © 2015. Published by Elsevier Ltd.

  11. Impediment to Spirit Drive on Sol 1806

    Science.gov (United States)

    2009-01-01

    The hazard avoidance camera on the front of NASA's Mars Exploration Rover Spirit took this image after a drive by Spirit on the 1,806th Martian day, or sol, (January 31, 2009) of Spirit's mission on the surface of Mars. The wheel at the bottom right of the image is Spirit's right-front wheel. Because that wheel no longer turns, Spirit drives backwards dragging that wheel. The drive on Sol 1806 covered about 30 centimeters (1 foot). The rover team had planned a longer drive, but Spirit stopped short, apparently from the right front wheel encountering the partially buried rock visible next to that wheel. The hazard avoidance cameras on the front and back of the rover provide wide-angle views. The hill on the horizon in the right half of this image is Husband Hill. Spirit reached the summit of Husband Hill in 2005.

  12. A development of the distributive law of points on the multi-wheeled machine wheels with electro-mechanical transmission, made under the scheme "motor-axis"

    Directory of Open Access Journals (Sweden)

    M. M. Jileikin

    2014-01-01

    Full Text Available Currently, developers of multi-wheeled vehicles (MWV show growing interest in electromechanical drive in the «motor-axis» implementation. However, in designing the traction electric drive (TED based on such approach the problems arise, primarily, from a lack of creating experience and of ready algorithmic solutions to control the traction motors. The use of methods to implement the individual TED is impossible because of the presence of cross-axle differential in the leading axle drive, which does not allow the input torque control of each wheel singly. The paper offers a law to control a traction electric drive of MWV leading axles that comprises the law to control the tractive effort torque and braking moment on the leading axles as well as algorithms of anti-lock brake and traction control systems.An analysis of simulation modeling results shows an efficiency of the developed law that allows control of the traction electric drive of MWV leading axles. The control law includes an algorithm to control the tractive effort torque and braking moment on the driving-wheels, as well as algorithms of anti-lock brake and traction systems.At stationary (constant speed rotation and non-stationary (elk test maneuvering there was no spin of vehicle wheels. Angular speeds of the wheels vary smoothly. Partial loss of vehicle stability when making maneuvers on ice may be reduced through development of algorithms for dynamic stabilization, which will improve the MWV road-holding and trajectory ability. Fullscale tests of MWV with traction electric drive implemented using a “motor-axis" approach are required to have a final answer on the performance and effectiveness of the developed control law.

  13. Rear suspension design for an in-wheel-drive electric car

    NARCIS (Netherlands)

    George, Ashwin Dayal; Besselink, Igo

    2016-01-01

    The in-wheel motor configuration can provide more flexibility to electric car design, making the car more compact and lightweight. However, current suspension systems are not designed to incorporate an in-wheel powertrain, and studies have shown deterioration in ride comfort and handling when more

  14. Study on Drive System of Hybrid Tree Harvester

    Directory of Open Access Journals (Sweden)

    Shen Rong-feng

    2017-01-01

    Full Text Available Hybrid tree harvester with a 60 kW diesel engine combined with a battery pile could be a “green” forest harvesting and transportation system. With the new design, the diesel engine maintains a constant engine speed, keeping fuel consumption low while charging the batteries that drive the forwarder. As an additional energy saving method, the electric motors work as generators to charge the battery pile when the vehicle moves downhill. The vehicle is equipped with six large wheels providing high clearance over uneven terrain while reducing ground pressure. Each wheel is driven via a hub gear by its own alternating current motor, and each of the three wheel pairs can be steered independently. The combination of the diesel engine and six electric motors provides plenty of power for heavy lifting and pulling. The main component parameters of the drive system are calculated and optimized with a set of dynamics and simulated with AVL Cruise software. The results provide practical insights for the fuel tree harvester and are helpful to reduce the structure and size of the tree harvester. Advantage Environment provides information about existing and future products designed to reduce environmental impacts.

  15. Study on the Effect of Steel Wheel and Ground on Single Steel Vibratory Roller

    Science.gov (United States)

    Li, Jiabo; You, Guanghui; Qiao, Jiabin; Ye, Min; Guo, Jin; Zhang, Hongyang

    2018-03-01

    In the compacting operation of single drum vibratory roller, the forces acting on the foundation of drum include the weight of the drum, the weight of the frame, the exciting force and so on. Based on the theoretical study of ground mechanics, this paper analyzes and calculates the forces acting on the steel wheel and the ground, and obtains the distribution of the laminar stress in the ground when the working plane vibrates. Derive the formula of dynamic compressive stress and static compressive stress in the foundation during vibration compaction. Through the compaction test of the soil trough of 20T single drum roller, the compressive stress data of the soil hydraulic field are obtained. The data of the dynamic compressive stress and the static compressive stress of each layer during the third compaction are obtained, and the theoretical research is verified.

  16. Predicting drive for muscularity behavioural engagement from body image attitudes and emotions.

    Science.gov (United States)

    Tod, David; Edwards, Christian

    2013-01-01

    We examined the potential moderating effects of appearance investment, body image disturbance, and situational body image dysphoria on the drive for muscularity attitude-behaviour relationship. Participants (339 British college men, M(AGE)=20.00 years, SD=2.59) completed drive for muscularity attitude and behaviour, appearance investment, body image disturbance, and situational body image dysphoria measures. Results indicated higher levels of appearance investment, body image disturbance, and situational body image dysphoria were associated with increases in the drive for muscularity attitude's relationship with physique-enhancing behavioural engagement. Results help extend recent research that has moved beyond identifying correlates to examining ways that groups of variables interact to predict drive for muscularity behavioural engagement and may contribute to theory development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Mathematical model of rolling an elastic wheel over deformable support base

    Science.gov (United States)

    Volskaia, V. N.; Zhileykin, M. M.; Zakharov, A. Y.

    2018-02-01

    One of the main direction of economic growth in Russia remains to be a speedy development of north and northeast regions that are the constituents of the 60 percent of the country territory. The further development of these territories requires new methods and technologies for solving transport and technological problems when off-road transportation of cargoes and people is conducting. One of the fundamental methods of patency prediction is imitation modeling of wheeled vehicles movement in different operating conditions. Both deformable properties of tires and physical and mechanical properties of the ground: normal tire deflection and gauge depth; variation of contact patch area depending on the load and pressure of air in the tire; existence of hysteresis losses in the tire material which are influencing on the rolling resistance due to friction processes between tire and ground in the contact patch; existence of the tangential reaction from the ground by entire contact area influence on the tractive patency. Nowadays there are two main trends in theoretical research of interaction wheeled propulsion device with ground: analytical method involving mathematical description of explored process and finite element method based on computational modeling. Mathematical models of interaction tire with the ground are used both in processes of interaction individual wheeled propulsion device with ground and researches of mobile vehicle dynamical models operated in specific road and climate conditions. One of the most significant imperfection of these models is the description of interaction wheel with flat deformable support base whereas profile of real support base surface has essential height of unevenness which is commensurate with radius of the wheel. The description of processes taking place in the ground under influence of the wheeled propulsion device using the finite element method is relatively new but most applicable lately. The application of this method allows

  18. Acceptance of and Engagement in Risky Driving Behaviors by Teenagers

    Science.gov (United States)

    Sarkar, Sheila; Andreas, Marie

    2004-01-01

    Data gathered from 1,430 teenage student drivers and 880 teenage traffic violators were used to examine the levels of exposure to risky driving behaviors and perceptions concerning the level of danger of such behaviors. For student drivers, 55% reported exposure to risky driving by being in a car with a driver engaging in such activities as drunk…

  19. Analysis of motion of the three wheeled mobile platform

    Directory of Open Access Journals (Sweden)

    Jaskot Anna

    2018-01-01

    Full Text Available The work is dedicated to the designing motion of the three wheeled mobile platform under the unsteady conditions. In this paper the results of the analysis based on the dynamics model of the three wheeled mobile robot, with two rear wheels and one front wheel has been included The prototype has been developed by the author's construction assumptions that is useful to realize the motion of the platform in a various configurations of wheel drives, including control of the active forces and the direction of their settings while driving. Friction forces, in longitudinal and in the transverse directions, are considered in the proposed model. Relation between friction and active forces are also included. The motion parameters of the mobile platform has been determined by adopting classical approach of mechanics. The formulated initial problem of platform motion has been solved numerically using the Runge-Kutta method of the fourth order. Results of motion analysis with motion parameters values are determined and sample results are presented.

  20. Design, Construction and Evaluation of an Interchangeable Digital System to Measure Slip and Ground Speed of Existing 2WD Tractors in Iran

    Directory of Open Access Journals (Sweden)

    M Khosravi

    2012-05-01

    Full Text Available The majority of existing tractors in Iran are not equipped with any tools to measure and display slip and ground speed. This is mainly due to the lack of national standards for measuring tools and instruments of tractors. In current research, an interchangeable system for two wheel drive tractors has been designed. Furthermore, it has been assessed after construction. To measure actual and theoretical ground speed, four rotary encoders for sensing the rotation of front and rear wheels have been utilized. Slip and ground speed were measured by means of software which has been developed in an ATmega16PU microprocessor. The measured slip and speed are digitally displayed on tractor dashboard. To evaluate the performance of the system, the measured values of ground speed and slip were compared with their calculated values obtained from conventional method. The Micro-controller has been programmed in such a way that the effect of front wheel sliding on slip is eliminated. In all evaluation conditions (in field and on asphalt, the maximum difference between system measurements for slip and speed and calculated slip and speed via conventional method was 2.4% and 0.2 km h-1, respectively. With slight alteration this system can be fitted on any kind of exiting two wheel drive tractors in the country.

  1. Mixed-μ magnetic levitation for advanced ground transport system

    International Nuclear Information System (INIS)

    Russell, F.M.

    1977-12-01

    The possibility of applying the mixed-μ principle for magnetic levitation to ground transport systems is examined. The system is developed specifically for suspension and useful lift to passive weight ratios exceeding 8:1 have been calculated. Application to a hybrid system where conventional wheel drive is used in conjunction with magnetic levitation is explained for urban transport. (author)

  2. Grinding Characteristics Of Directionally Aligned SiC Whisker Wheel-Comparison With Al2O3 Fiber Wheel

    Institute of Scientific and Technical Information of China (English)

    魏源迁; 山口胜美; 菊泽贤二; 洞口严; 中根正喜

    2003-01-01

    A unique SiC whisker wheel was invented,in which the whiskers were aligned normally to the grinding wheel surface.In this paper,grindabilities of the SiC whisker wheel are investigated and compared with those of other wheels of SiC grains,Al2O3 grains,as well as Al2O3 long and short fibres which were also aligned normally to the grinding wheel surface,respectively.The main research contents concern grinding characteristics of a directionally aligned SiC whisker wheel such as material-removal volume,wheel-wear rates,integrity of the ground surfaces,grinding ratios and grinding efficiency.Furthermore,grinding wheels of whiskers and fibres have a common disadvantage:they tend to load easily.The authors have proposed a simple method of loading-free grinding to overcome this propensity and investigate some related grinding characteristics under loading-free grinding conditions.

  3. Vehicle Velocity and Roll Angle Estimation with Road and Friction Adaptation for Four-Wheel Independent Drive Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Linhui Zhao

    2014-01-01

    Full Text Available Vehicle velocity and roll angle are important information for active safety control systems of four-wheel independent drive electric vehicle. In order to obtain robustness estimation of vehicle velocity and roll angle, a novel method is proposed based on vehicle dynamics and the measurement information provided by the sensors equipped in modern cars. The method is robust with respect to different road and friction conditions. Firstly, the dynamic characteristics of four-wheel independent drive electric vehicle are analyzed, and a four-degree-of-freedom nonlinear dynamic model of vehicle and a tire longitudinal dynamic equation are established. The relationship between the longitudinal and lateral friction forces is derived based on Dugoff tire model. The unknown input reconstruction technique of sliding mode observer is used to achieve longitudinal tire friction force estimation. A simple observer is designed for the estimation of the roll angle of the vehicle. And then using the relationship, the estimated longitudinal friction forces and roll angle, a sliding mode observer for vehicle velocity estimation is provided, which does not need to know the tire-road friction coefficient and road angles. Finally, the proposed method is evaluated experimentally under a variety of maneuvers and road conditions.

  4. Hybrid Control Design for a Wheeled Mobile Robot

    DEFF Research Database (Denmark)

    Bak, Thomas; Bendtsen, Jan Dimon; Ravn, Anders Peter

    We present a hybrid systems solution to the problem of trajectory tracking for a four-wheel steered four-wheel driven mobile robot. The robot is modelled as a non-holonomic dynamic system subject to pure rolling, no-slip constraints. Under normal driving conditions, a nonlinear trajectory tracking...

  5. Hybrid Control Design for a Wheeled Mobile Robot

    DEFF Research Database (Denmark)

    Bak, Thomas; Bendtsen, Jan Dimon; Ravn, Anders Peter

    2003-01-01

    We present a hybrid systems solution to the problem of trajectory tracking for a four-wheel steered four-wheel driven mobile robot. The robot is modelled as a non-holonomic dynamic system subject to pure rolling, no-slip constraints. Under normal driving conditions, a nonlinear trajectory tracking...

  6. Hybrid Control Design for a Wheeled Mobile Robot

    DEFF Research Database (Denmark)

    Bak, Thomas; Bendtsen, Jan Dimon; Ravn, Anders Peter

    2003-01-01

    We present a hybrid systems solution to the problem of trajectory tracking for a four-wheel steered four-wheel driven mobile robot. The robot is modelled as a non-holonomic dynamic system subject to pure rolling, no-slip constraints. Under normal driving conditions, a nonlinear trajectory trackin...

  7. Performance Evaluation of an In-Wheel Motor Cooling System in an Electric Vehicle/Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Dong Hyun Lim

    2014-02-01

    Full Text Available High power and miniaturization of motors in an in-wheel drive system, which is installed inside the wheels of a vehicle, are required for directly driving the wheels. In addition, an efficient cooling system is required to ensure high driving performance and durability. This study experimentally evaluated the heat dissipation performance of a 35-kW-class large-capacity in-wheel motor equipped with an internal-circulation-type oil-cooling system that exhibits high cooling performance and can be easily miniaturized to this motor. Temperatures of the coil and stator core of cooling systems with and without a radiator were measured in real time under in-wheel motor driving conditions. It was found that operating the cooling system at a continuous-rating maximum speed without the radiator was difficult. We confirmed that under continuous-rating base speed and continuous-rating maximum speed driving conditions, the cooling system with the radiator showed thermally stable operation. Furthermore, under maximum-rating base speed and maximum-rating maximum speed driving conditions, the cooling system with the radiator provided additional driving times of approximately 22 s and 2 s, respectively.

  8. Preliminary Design and Investigation of Integrated Compressor with Composite Material Wheel

    Science.gov (United States)

    Wang, Jifeng; Müller, Norbert

    2012-06-01

    An integrated water vapor compressor with composite material wheel is developed and strength analysis using FEM is presented. The design of wound composite material allows for integrating all rotating parts of the drive that may simply reduce to only the rotor of the electrical motor, since no drive shaft is required anymore. This design can reduce the number of parts and mass, which is convenient for engineers to maintain the compressor. The electrical motors are brushless DC motors operating through a frequency drive and apply a torque on the wheels through the materials bonded in the wheel shrouds. This system allows a large amount of compression to be produced in a multi-stage compression setup. To determine the stress and vibration characteristics of this integrated compressor, numerical analysis is carried out using FEM. The simulation result shows that the integrated compressor with composite material wheel can be used in a chiller system where water as a refrigerant.

  9. Online Detection of Driver Fatigue Using Steering Wheel Angles for Real Driving Conditions

    Directory of Open Access Journals (Sweden)

    Zuojin Li

    2017-03-01

    Full Text Available This paper presents a drowsiness on-line detection system for monitoring driver fatigue level under real driving conditions, based on the data of steering wheel angles (SWA collected from sensors mounted on the steering lever. The proposed system firstly extracts approximate entropy (ApEnfeaturesfromfixedslidingwindowsonreal-timesteeringwheelanglestimeseries. Afterthat, this system linearizes the ApEn features series through an adaptive piecewise linear fitting using a given deviation. Then, the detection system calculates the warping distance between the linear features series of the sample data. Finally, this system uses the warping distance to determine the drowsiness state of the driver according to a designed binary decision classifier. The experimental data were collected from 14.68 h driving under real road conditions, including two fatigue levels: “wake” and “drowsy”. The results show that the proposed system is capable of working online with an average 78.01% accuracy, 29.35% false detections of the “awake” state, and 15.15% false detections of the “drowsy” state. The results also confirm that the proposed method based on SWA signal is valuable for applications in preventing traffic accidents caused by driver fatigue.

  10. Retrofitting of beaters with mono-drive at a beater-wheel mill; Nachruestung von Vorschlaegern mit Mono-Antrieb an einer Schlagradmuehle

    Energy Technology Data Exchange (ETDEWEB)

    Krecher, Johannes J.; Hildebrandt, Rainer [Lignite-Mono-Drive Engineering GmbH, Essen (Germany); Geradts, Paul [RWE Power AG, Grevenbroich (Germany)

    2008-07-01

    Due to a future energy crisis, the use of the domestic brown coal continuously must be strengthened. At the beginning of 2007, the power station Frimmersdorf of RWE Power AG (Essen, Federal Republic of Germany) commissioned Lignite-Mono-Drive Engineering GmbH (Essen, Federal Republic of Germany) with the retrofitting of a N90.60 beater-wheel mill to a mono-drive-system. Thus, the production losses of 20 GWh/a of the 150 MW brown coal block M should be avoided, and the performance of this brown coal block should be increased by nearly 3 MW. Apart from the milling process and drying process, the authors of the contribution under consideration describe the application and operation results of these mono-drive-mills.

  11. Efficient direct yaw moment control: tyre slip power loss minimisation for four-independent wheel drive vehicle

    Science.gov (United States)

    Kobayashi, Takao; Katsuyama, Etsuo; Sugiura, Hideki; Ono, Eiichi; Yamamoto, Masaki

    2018-05-01

    This paper proposes an efficient direct yaw moment control (DYC) capable of minimising tyre slip power loss on contact patches for a four-independent wheel drive vehicle. Simulations identified a significant power loss reduction with a direct yaw moment due to a change in steer characteristics during acceleration or deceleration while turning. Simultaneously, the vehicle motion can be stabilised. As a result, the proposed control method can ensure compatibility between vehicle dynamics performance and energy efficiency. This paper also describes the results of a full-vehicle simulation that was conducted to examine the effectiveness of the proposed DYC.

  12. Cyber Security Considerations for Autonomous Tactical Wheeled Vehicles

    Science.gov (United States)

    2016-04-01

    Update Will Enable Autonomous Driving. Retrieved August 6, 2015, from http://spectrum.ieee.org/: http://spectrum.ieee.org/ cars -that-think...Cyber Security Considerations for Autonomous Tactical Wheeled Vehicles 1 UNCLASSIFIED Cyber Security Considerations for... Autonomous Tactical Wheeled Vehicles Sebastian C Iovannitti 4/1/2016 Submitted to Lawrence Technological University College of Management in

  13. i3Drive, a 3D interactive driving simulator.

    Science.gov (United States)

    Ambroz, Miha; Prebil, Ivan

    2010-01-01

    i3Drive, a wheeled-vehicle simulator, can accurately simulate vehicles of various configurations with up to eight wheels in real time on a desktop PC. It presents the vehicle dynamics as an interactive animation in a virtual 3D environment. The application is fully GUI-controlled, giving users an easy overview of the simulation parameters and letting them adjust those parameters interactively. It models all relevant vehicle systems, including the mechanical models of the suspension, power train, and braking and steering systems. The simulation results generally correspond well with actual measurements, making the system useful for studying vehicle performance in various driving scenarios. i3Drive is thus a worthy complement to other, more complex tools for vehicle-dynamics simulation and analysis.

  14. The Ferris Wheel and Justifications of Curvature

    Science.gov (United States)

    Stevens, Irma E.; Moore, Kevin C.

    2016-01-01

    This report discusses the results of semi-structured clinical interviews with ten prospective secondary mathematics teachers who were provided with dynamic images of Ferris wheels. We asked the students to graph the relationship between the distance a rider traveled around the Ferris wheel and the height of the rider from the ground. We focus on…

  15. A mathematical model for predicting lane changes using the steering wheel angle.

    Science.gov (United States)

    Schmidt, Kim; Beggiato, Matthias; Hoffmann, Karl Heinz; Krems, Josef F

    2014-06-01

    Positive safety effects of advanced driver assistance systems can only become effective if drivers accept and use these systems. Early detection of driver's intention would allow for selective system activation and therefore reduce false alarms. This driving simulator study aims at exploring early predictors of lane changes. In total, 3111 lane changes of 51 participants on a simulated highway track were analyzed. Results show that drivers stopped their engagement in a secondary task about 7s before crossing the lane, which indicates a first planning phase of the maneuver. Subsequently, drivers start moving toward the lane, marking a mean steering wheel angle of 2.5°. Steering wheel angle as a directly measurable vehicle parameter appears as a promising early predictor of a lane change. A mathematical model of the steering wheel angle is presented, which is supposed to contribute for predicting lane change maneuvers. The mathematical model will be part of a further predictor of lane changes. This predictor can be a new advanced driver assistance system able to recognize a driver's intention. With this knowledge, other systems can be activated or deactivated so drivers get no annoying and exhausting alarm signals. This is one way how we can increase the acceptance of assistance systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Assessing drivers' response during automated driver support system failures with non-driving tasks.

    Science.gov (United States)

    Shen, Sijun; Neyens, David M

    2017-06-01

    With the increase in automated driver support systems, drivers are shifting from operating their vehicles to supervising their automation. As a result, it is important to understand how drivers interact with these automated systems and evaluate their effect on driver responses to safety critical events. This study aimed to identify how drivers responded when experiencing a safety critical event in automated vehicles while also engaged in non-driving tasks. In total 48 participants were included in this driving simulator study with two levels of automated driving: (a) driving with no automation and (b) driving with adaptive cruise control (ACC) and lane keeping (LK) systems engaged; and also two levels of a non-driving task (a) watching a movie or (b) no non-driving task. In addition to driving performance measures, non-driving task performance and the mean glance duration for the non-driving task were compared between the two levels of automated driving. Drivers using the automated systems responded worse than those manually driving in terms of reaction time, lane departure duration, and maximum steering wheel angle to an induced lane departure event. These results also found that non-driving tasks further impaired driver responses to a safety critical event in the automated system condition. In the automated driving condition, driver responses to the safety critical events were slower, especially when engaged in a non-driving task. Traditional driver performance variables may not necessarily effectively and accurately evaluate driver responses to events when supervising autonomous vehicle systems. Thus, it is important to develop and use appropriate variables to quantify drivers' performance under these conditions. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

  17. Engagement with the TeenDrivingPlan and diversity of teens' supervised practice driving: lessons for internet-based learner driver interventions.

    Science.gov (United States)

    Winston, Flaura K; Mirman, Jessica H; Curry, Allison E; Pfeiffer, Melissa R; Elliott, Michael R; Durbin, Dennis R

    2015-02-01

    Inexperienced, less-skilled driving characterises many newly licensed drivers and contributes to high crash rates. A randomised trial of TeenDrivingPlan (TDP), a new learner driver phase internet-based intervention, demonstrated effectiveness in improving safety relevant, on-road driving behaviour, primarily through greater driving practice diversity. To inform future learner driver interventions, this analysis examined TDP use and its association with practice diversity. Posthoc analysis of data from teen/parent dyads (n=107), enrolled early in learner phase and assigned to treatment arm in randomised trial. Inserted software beacons captured TDP use data. Electronic surveys completed by parents and teens assessed diversity of practice driving and TDP usability ratings at 24 weeks (end of study period). Most families (84%) used TDP early in the learner period; however, the number of TDP sessions in the first week was three times higher among dyads who achieved greater practice diversity than those with less. By week five many families still engaged with TDP, but differences in TDP use could not be detected between families with high versus low practice diversity. Usability was not a major issue for this sample based on largely positive user ratings. An engaging internet-based intervention, such as TDP, can support families in achieving high practice diversity. Future learner driver interventions should provide important information early in the learner period when engagement is greatest, encourage continued learning as part of logging practice drives, and incorporate monitoring software for further personalisation to meet family needs. NCT01498575. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Characteristics of The Magnet Wheel As A Magnetic Levitation Device of Induction Type

    OpenAIRE

    藤井, 信男; 小川, 幸吉; 松本, 敏雄; Nobuo, FUJII; Kokichi, OGAWA; Toshio, MATSUMOTO; 九州大学; 大分大学; 安川電機; Kyushu University; Oita University; Yaskawa Electric Co., Ltd.

    1996-01-01

    A new type of magnetic wheel called the "magnet wheel" has been proposed. The magnet wheel has both magnetic levitation and linear drive functions combined into one. In the magnet wheel, the permanent magnets are rotated over the conducting plate so that an induction type of repulsive lift force is obtained. To produce thrust from the drag torque which is simultaneously induced with the lift force, the "tilt type" and "partial overlap type" magnet wheels have been proposed. Poor power factor ...

  19. Torsional Moment Measurement on Bucket Wheel Shaft of Giant Machine

    Directory of Open Access Journals (Sweden)

    Jiří FRIES

    2011-06-01

    Full Text Available Bucket wheel loading at the present time (torsional moment on wheel shaft, peripheral cutting force is determined from electromotor incoming power or reaction force measured on gearbox hinge. Both methods together are weighted by steel construction absorption of driving units and by inertial forces of motor rotating parts. In the article is described direct method of the torsional moment measurement, which eliminates mentioned unfavourable impacts except absorption of steel construction of bucket wheel itself.

  20. Mid-sized omnidirectional robot with hydraulic drive and steering

    Science.gov (United States)

    Wood, Carl G.; Perry, Trent; Cook, Douglas; Maxfield, Russell; Davidson, Morgan E.

    2003-09-01

    Through funding from the US Army-Tank-Automotive and Armaments Command's (TACOM) Intelligent Mobility Program, Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS) has developed the T-series of omni-directional robots based on the USU omni-directional vehicle (ODV) technology. The ODV provides independent computer control of steering and drive in a single wheel assembly. By putting multiple omni-directional (OD) wheels on a chassis, a vehicle is capable of uncoupled translational and rotational motion. Previous robots in the series, the T1, T2, T3, ODIS, ODIS-T, and ODIS-S have all used OD wheels based on electric motors. The T4 weighs approximately 1400 lbs and features a 4-wheel drive wheel configuration. Each wheel assembly consists of a hydraulic drive motor and a hydraulic steering motor. A gasoline engine is used to power both the hydraulic and electrical systems. The paper presents an overview of the mechanical design of the vehicle as well as potential uses of this technology in fielded systems.

  1. Driving After a Stroke

    Science.gov (United States)

    ... 23,2015 Can I drive after a stroke? Driving is often a major concern after someone has a stroke. It’s not unusual for stroke survivors to want to drive. Being able to get around after a stroke is important. Safety behind the wheel is even more important after ...

  2. The use of an axial flux permanent magnet in-wheel direct drive in an electric bicycle

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, P.R. [Norwegian University of Science and Technology, Trondheim (Norway). Dept. of Electrical Power Engineering; Patterson, D.; O' Keefe, C.; Swenson, J. [Northern Territory University, Darwin (Australia). NT Centre for Energy Research

    2001-03-01

    The research described in this paper concentrates on the development of an electronic converter. Successful completion of this converter provides the final component for the larger electric bicycle project. The controller developed for the bicycle is rated at 400 W and is hard-switched. It uses MOSFETs as power switching devices. There are three Hall effect sensors placed 120 electrical degrees apart from each other in the motor for velocity and position sensing. The torque generated by the machine is controlled by hysteresis band current control. In order for the motor/controller to be commercially viable, particular attention was paid to the costs of the controller. The result, an efficient yet cheap controller. Measurement of efficiency is difficult in high performance power electronic controllers (Patterson DJA very high efficiency controller for an axial flux permanent magnet wheel drive in a solar powered vehicle. 2nd IEEE International Conference on Power Electronics Drives and Energy Systems for Industrial Growth, IEEE PEDES '98, Perth, 30th November-3rd December, 1998). The paper includes discussion of a calorimetric method for measurement. (author)

  3. Work stress, fatigue and risk behaviors at the wheel: Data to assess the association between psychosocial work factors and risky driving on Bus Rapid Transit drivers

    Directory of Open Access Journals (Sweden)

    Sergio Useche

    2017-12-01

    Full Text Available This Data in Brief (DiB article presents a hierarchical multiple linear regression model that examine the associations between psychosocial work factors and risk behaviors at the wheel in Bus Rapid Transit (BRT drivers (n=524. The data were collected using a structured self-administrable questionnaire made of measurements of wok stress (job strain and effort- reward imbalance, fatigue (need for recovery and chronic fatigue, psychological distress and demographics (professional driving experience, hours driven per day and days working per week. The data contains 4 parts: descriptive statistics, bivariate correlations between the study variables and a regression model predicting risk behaviors at the wheel and the entire study dataset. For further information, it is convenient to read the full article entitled “Stress-related Psychosocial Factors at Work, Fatigue, and Risky Driving Behavior in Bus Rapid Transport (BRT Drivers”, published in Accident Analysis & Prevention. Keywords: Professional drivers, Work stress, Fatigue, Psychological distress, Risk behaviors, Bus Rapid Transport, BRT

  4. Using SHRP 2 naturalistic driving data to assess drivers' speed choice while being engaged in different secondary tasks.

    Science.gov (United States)

    Schneidereit, Tina; Petzoldt, Tibor; Keinath, Andreas; Krems, Josef F

    2017-09-01

    The engagement in secondary tasks while driving has been found to result in considerable impairments of driving performance. Texting has especially been suspected to be associated with an increased crash risk. At the same time, there is evidence that drivers use various self-regulating strategies to compensate for the increased demands caused by secondary task engagement. One of the findings reported from multiple studies is a reduction in driving speed. However, most of these studies are of experimental nature and do not let the drivers decide for themselves to (not) engage in the secondary task, and therefore, eliminate other strategies of self-regulation (e.g., postponing the task). The goal of the present analysis was to investigate if secondary task engagement results in speed adjustment also under naturalistic conditions. Our analysis relied on data of the SHRP 2 naturalistic driving study. To minimize the influence of potentially confounding factors on drivers' speed choice, we focused on episodes of free flow driving on interstates/highways. Driving speed was analyzed before, during, and after texting, smoking, eating, and adjusting/monitoring radio or climate control; in a total of 403 episodes. Data show some indication for speed adjustment for texting, especially when driving with high speed. However, the effect sizes were small and behavioral patterns varied considerably between drivers. The engagement in the other tasks did not influence drivers' speed behavior significantly. While drivers might indeed reduce speed slightly to accommodate for secondary task engagement, other forms of adaptation (e.g., strategic decisions) might play a more important role in a natural driving environment. The use of naturalistic driving data to study drivers' self-regulatory behavior at an operational level has proven to be promising. Still, in order to obtain a comprehensive understanding about drivers' self-regulatory behavior, a mixed-method approach is required

  5. What technologies do people engage with while driving and why?

    Science.gov (United States)

    Parnell, Katie J; Stanton, Neville A; Plant, Katherine L

    2018-02-01

    This paper presents the findings of a semi-structured interview study that was conducted to identify drivers' self-reported likelihood of engaging with technologies that are now commonly found in modern automobiles. Previous research has focused on the effect these technological tasks have on driving performance, but there has been less focus on how, why and when drivers choose to engage with them. As distraction remains a significant contributor to road accidents, an understanding of why it occurs will give important insights into how it can be prevented. A semi-structured interview schedule was developed to allow drivers to discuss the factors that influence their decision to engage with a variety of different technologies. The methodology facilitated both quantitative ratings of the drivers' likelihood of engaging in a variety of tasks and qualitative insights into why. Age and gender had some influence on the propensity to engage, in line with other findings in the literature, as did road type and task type. The reasons drivers gave for why they engage with potentially distracting tasks inform recommendations for preventing distraction related accidents from the increasingly prevalent sources of technologies available to drivers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Design and Analysis of a Novel Speed-Changing Wheel Hub with an Integrated Electric Motor for Electric Bicycles

    Directory of Open Access Journals (Sweden)

    Yi-Chang Wu

    2013-01-01

    Full Text Available The aim of this paper is to present an innovative electromechanical device which integrates a brushless DC (BLDC hub motor with a speed-changing wheel hub stored on the rear wheel of an electric bicycle. It combines a power source and a speed-changing mechanism to simultaneously provide functions of power generation and transmission for electric bicycles. As part of the proposed integrated device, the wheel hub consists of a basic planetary gear train providing three forward speeds including a low-speed gear, a direct drive, and a high-speed gear. Each gear is manually controlled by the shift control sleeve to selectively engage or disengage four pawl-and-ratchet clutches based on its clutching sequence table. The number of gear teeth of each gear element of the wheel hub is synthesized. The BLDC hub motor is an exterior-rotor-type permanent-magnet synchronous motor. Two-dimensional finite-element analysis (FEA software is employed to facilitate the motor design and performance analysis. An analysis of the power transmission path at each gear is provided to verify the validity of the proposed design. The results of this work are beneficial to the embodiment, design, and development of novel electromechanical devices for the power and transmission systems of electric bicycles.

  7. Associations Between Driving Performance and Engaging in Secondary Tasks: A Systematic Review

    Science.gov (United States)

    Ferdinand, Alva O.

    2014-01-01

    We conducted a systematic review and meta-analysis of the literature examining the relationship between driving performance and engaging in secondary tasks. We extracted data from abstracts of 206 empirical articles published between 1968 and 2012 and developed a logistic regression model to identify correlates of a detrimental relationship between secondary tasks and driving performance. Of 350 analyses, 80% reported finding a detrimental relationship. Studies using experimental designs were 37% less likely to report a detrimental relationship (P = .014). Studies examining mobile phone use while driving were 16% more likely to find such a relationship (P = .009). Quasi-experiments can better determine the effects of secondary tasks on driving performance and consequently serve to inform policymakers interested in reducing distracted driving and increasing roadway safety. PMID:24432925

  8. Job demands and driving anger: The roles of emotional exhaustion and work engagement.

    Science.gov (United States)

    Li, Feng; Wang, Guangxi; Li, Yongjuan; Zhou, Ronggang

    2017-01-01

    This study aimed to examine the effects of both hindrance and challenge demands on driving anger within the framework of the job demands-resources (JD-R) model. We collected self-reported data from 411 office workers driving to and from work each day in five cities in China. The results from a structural equation modeling analysis indicated that both hindrance and challenge demands were positively related to emotional exhaustion, which was in turn positively correlated with driving anger. Moreover, work engagement was positively correlated with driving anger. Implications of the present findings regarding both the JD-R model and driving safety research are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Using special additions to preparation of the moulding mixture for casting steel parts of drive wheel type

    Science.gov (United States)

    Josan, A.; Pinca Bretotean, C.

    2015-06-01

    The paper presents the possibility of using special additions to the execution of moulding mixtures for steel castings, drive wheel type. Critical analysis of moulding technology leads to the idea that most defects appear due to using improper moulding mixture. Using a improper moulding mixture leads to penetration of steel in moulding mixture, resulting in the formation of adherences, due to inadequate refractarity of the mould and core mixtures. Using only the unique mixture to the moulding leads to increasing consumption of new sand, respectively to the increase of price of piece. Acording to the dates registered in the industrial practice is necessary to use the special additions to obtain the moulding mixtures, carbonaceous materials respectively.

  10. PIV measurement of the flow past a generic car body with wheels at LES applicable Reynolds number

    International Nuclear Information System (INIS)

    Gulyás, András; Bodor, Ágnes; Regert, Tamas; Jánosi, Imre M.

    2013-01-01

    Highlights: • Two reviewers required changes that were feasible to carry out. • Two changes were domanded from the first reviewer which were effectuated. • Twenty eight minor changes were asked by the second reviewer, which are corrected in detail. • Figures are updated to higher resolution and improved in quality in general. -- Abstract: Experiments by using 2D–2C Particle Image Velocimetry (PIV) were carried out and reported concerning the flow field past a generic car body (modified Ahmed body) which is equipped with wheels and wheel-arches. The Reynolds number was chosen to not exceed 2E+5 based on the height of the Ahmed body which makes it possible to investigate the same configuration by means of Large Eddy Simulation (LES). The wheels were rotating but the ground was stationary. The wheel-ground contact was realized by means of small rectangular openings below the wheels in the ground plane in which the wheels were immersed. The transition contour of the immersed wheels and the ground, as well as the rectangular openings below the wheels were properly sealed to prevent parasite flow and to provide well defined boundary conditions for an upcoming LES investigation. The flow field was measured in several planes with normal vectors pointing towards the directions normal to the free stream. Statistical characteristics of the flow are provided and discussed

  11. In-core monitor drive mechanism

    International Nuclear Information System (INIS)

    Hattori, Kunimitsu; Ishii, Yoshimi.

    1969-01-01

    Instruments for measuring the neutron flux in a reactor are hung at the upper end of a shuttle tube connected to the upper portion of a perforated tube a plurality of the holes of which are engaged at all times with the teeth of an endless chain. The endless chain is driven by a sprocket integrated with a worm wheel shaft driven by a motor through a flexible shaft. The perforated tube is capable of being smoothly driven vertically into the reactor core without causing any noise. Since the tube is driven through a plurality of the teeth of the endless chain, the dimensions of the sprockets and other associated parts can be reduced to make the entire drive mechanism more compact. (Ohno, Y.)

  12. Modeling of traction-coupling properties of wheel propulsor

    Science.gov (United States)

    Sakhapov, R. L.; Nikolaeva, R. V.; Gatiyatullin, M. H.; Makhmutov, M. M.

    2017-12-01

    In conditions of operation of aggregates on soils with low bearing capacity, the main performance indicators of their operation are determined by the properties of retaining the functional qualities of the propulsor. Therefore, the parameters of the anti-skid device can not be calculated by only one criterion. The equipment of propellers with anti-skid devices, which allow to reduce the compaction effect of the propulsion device on the soil, seems to be a rational solution to the problem of increasing traction and coupling properties of the driving wheels. The mathematical model is based on the study of the interaction of the driving wheel with anti-skid devices and a deformable bearing surface, which takes into account the wheel diameter, skid coefficient, the parameters of the anti-skid device, the physical and mechanical properties of the soil. As a basic mathematical model that determines the dependence of the coupling properties on the wheel parameters, the model obtained as a result of integration and reflecting the process of soil deformation from the shear stress is adopted. The total value of the resistance forces will determine the force of the hitch pressure on the horizontal soil layers, and the value of its deformation is the degree of wheel slippage. When the anti-skid devices interact with the soil, the traction capacity of the wheel is composed of shear forces, soil shear and soil deformation forces with detachable hooks. As a result of the interaction of the hook with the soil, the latter presses against the walls of the hook with the force equal to the sum of the hook load and the resistance to movement. During operation, the linear dimensions of the hook will decrease, which is not taken into account by the safety factor. Abrasive wear of the thickness of the hook is approximately proportional to the work of friction caused by the movement of the hook when inserted into the soil and slipping the wheel.

  13. Biologically Inspired Modular Neural Control for a Leg-Wheel Hybrid Robot

    DEFF Research Database (Denmark)

    Manoonpong, Poramate; Wörgötter, Florentin; Laksanacharoen, Pudit

    2014-01-01

    In this article we present modular neural control for a leg-wheel hybrid robot consisting of three legs with omnidirectional wheels. This neural control has four main modules having their functional origin in biological neural systems. A minimal recurrent control (MRC) module is for sensory signal...... processing and state memorization. Its outputs drive two front wheels while the rear wheel is controlled through a velocity regulating network (VRN) module. In parallel, a neural oscillator network module serves as a central pattern generator (CPG) controls leg movements for sidestepping. Stepping directions...... or they can serve as useful modules for other module-based neural control applications....

  14. Forces on wheels and fuel consumption in cars

    Science.gov (United States)

    Güémez, J.; Fiolhais, M.

    2013-07-01

    Motivated by real classroom discussions, we analyze the forces acting on moving vehicles, specifically friction on their wheels. In typical front-wheel-drive cars when the car accelerates these forces are in the forward direction in the front wheels, but they are in the opposite direction in the rear wheels. The situation may be intriguing for students, but it may also be helpful and stimulating to clarify the role of friction forces on rolling objects. In this paper we also study the thermodynamical aspects of an accelerating car, relating the distance traveled to the amount of fuel consumed. The fuel consumption is explicitly shown to be Galilean invariant and we identify the Gibbs free energy as the relevant quantity that enters into the thermodynamical description of the accelerating car. The more realistic case of the car's motion with the dragging forces taken into account is also discussed.

  15. Forces on wheels and fuel consumption in cars

    International Nuclear Information System (INIS)

    Güémez, J; Fiolhais, M

    2013-01-01

    Motivated by real classroom discussions, we analyze the forces acting on moving vehicles, specifically friction on their wheels. In typical front-wheel-drive cars when the car accelerates these forces are in the forward direction in the front wheels, but they are in the opposite direction in the rear wheels. The situation may be intriguing for students, but it may also be helpful and stimulating to clarify the role of friction forces on rolling objects. In this paper we also study the thermodynamical aspects of an accelerating car, relating the distance traveled to the amount of fuel consumed. The fuel consumption is explicitly shown to be Galilean invariant and we identify the Gibbs free energy as the relevant quantity that enters into the thermodynamical description of the accelerating car. The more realistic case of the car's motion with the dragging forces taken into account is also discussed. (paper)

  16. Ground effect aerodynamics of racing cars

    OpenAIRE

    Zhang, Xin; Toet, Willem; Zerihan, Jonathan

    2006-01-01

    We review the progress made during the last thirty years on ground effect aerodynamics associated with race cars, in particular open wheel race cars. Ground effect aerodynamics of race cars is concerned with generating downforce, principally via low pressure on the surfaces nearest to the ground. The “ground effected” parts of an open wheeled car's aerodynamics are the most aerodynamically efficient and contribute less drag than that associated with, for example, an upper rear wing. Whilst dr...

  17. Modeling Driving Behavior at Roundabouts: Impact of Roundabout Layout and Surrounding Traffic on Driving Behavior

    OpenAIRE

    Zhao, Min; Käthner, David; Söffker, Dirk; Jipp, Meike; Lemmer, Karsten

    2017-01-01

    Driving behavior prediction at roundabouts is an important challenge to improve driving safety by supporting drivers with intelligent assistance systems. To predict the driving behavior effciently steering wheel status was proven to have robust predictability based on a Support Vector Machine algorithm. Previous research has not considered potential effects of roundabout layout and surrounding traffic on driving behavior, but that consideration can certainly improve the prediction results....

  18. Experiments on a Tail-wheel Shimmy

    Science.gov (United States)

    Harling, R; Dietz, O

    1954-01-01

    Model tests on the "running belt" and tests with a full-scale tail wheel were made on a rotating drum as well as on a runway in order to investigate the causes of the undesirable shimmy phenomena frequently occurring on airplane tail wheels, and the means of avoiding them. The small model (scale 1:10) permitted simulation of the mass, moments of inertia, and fuselage stiffness of the airplane and determination of their influence on the shimmy, whereas by means of the larger model with pneumatic tires (scale 1:2) more accurate investigations were made on the tail wheel itself. The results of drum and road tests show good agreement with one another and with model values. Detailed investigations were made regarding the dependence of the shimmy tendency on trail, rolling speed, load, size of tires, ground friction,and inclination of the swivel axis; furthermore, regarding the influence of devices with restoring effect on the tail wheel, and the friction damping required for prevention of shimmy. Finally observations from slow-motion pictures are reported and conclusions drawn concerning the influence of tire deformation.

  19. Sleepiness at the wheel across Europe: a survey of 19 countries.

    Science.gov (United States)

    Gonçalves, Marta; Amici, Roberto; Lucas, Raquel; Åkerstedt, Torbjörn; Cirignotta, Fabio; Horne, Jim; Léger, Damien; McNicholas, Walter T; Partinen, Markku; Téran-Santos, Joaquín; Peigneux, Philippe; Grote, Ludger

    2015-06-01

    The European Sleep Research Society aimed to estimate the prevalence, determinants and consequences of falling asleep at the wheel. In total, 12 434 questionnaires were obtained from 19 countries using an anonymous online questionnaire that collected demographic and sleep-related data, driving behaviour, history of drowsy driving and accidents. Associations were quantified using multivariate logistic regression. The average prevalence of falling asleep at the wheel in the previous 2 years was 17%. Among respondents who fell asleep, the median prevalence of sleep-related accidents was 7.0% (13.2% involved hospital care and 3.6% caused fatalities). The most frequently perceived reasons for falling asleep at the wheel were poor sleep in the previous night (42.5%) and poor sleeping habits in general (34.1%). Falling asleep was more frequent in the Netherlands [odds ratio = 3.55 (95% confidence interval: 1.97; 6.39)] and Austria [2.34 (1.75; 3.13)], followed by Belgium [1.52 (1.28; 1.81)], Portugal [1.34 (1.13, 1.58)], Poland [1.22 (1.06; 1.40)] and France [1.20 (1.05; 1.38)]. Lower odds were found in Croatia [0.36 (0.21; 0.61)], Slovenia [0.62 (0.43; 0.89)] and Italy [0.65 (0.53; 0.79)]. Individual determinants of falling asleep were younger age; male gender [1.79 (1.61; 2.00)]; driving ≥20 000 km year [2.02 (1.74; 2.35)]; higher daytime sleepiness [7.49 (6.26; 8.95)] and high risk of obstructive sleep apnea syndrome [3.48 (2.78; 4.36) in men]. This Pan European survey demonstrates that drowsy driving is a major safety hazard throughout Europe. It emphasizes the importance of joint research and policy efforts to reduce the burden of sleepiness at the wheel for European drivers.

  20. DC Brushless Motor Control Design and Preliminary Testing for Independent 4-Wheel Drive Rev-11 Robotic Platform

    Directory of Open Access Journals (Sweden)

    Roni Permana Saputra

    2012-03-01

    Full Text Available This paper discusses the design of control system for brushless DC motor using microcontroller ATMega 16 that will be applied to an independent 4-wheel drive Mobile Robot LIPI version 2 (REV-11. The control system consists of two parts which are brushless DC motor control module and supervisory control module that coordinates the desired command to the motor control module. To control the REV-11 platform, supervisory control transmit the reference data of speed and direction of motor to control the speed and direction of each actuator on the platform REV-11. From the test results it is concluded that the designed control system work properly to coordinate and control the speed and direction of motion of the actuator motor REV-11 platform. 

  1. Robust balancing and position control of a single spherical wheeled mobile platform

    OpenAIRE

    Yavuz, Fırat; Yavuz, Firat; Ünel, Mustafa; Unel, Mustafa

    2016-01-01

    Self-balancing mobile platforms with single spherical wheel, generally called ballbots, are suitable example of underactuated systems. Balancing control of a ballbot platform, which aims to maintain the upright orientation by rejecting external disturbances, is important during station keeping or trajectory tracking. In this paper, acceleration based balancing and position control of a single spherical wheeled mobile platform that has three single-row omniwheel drive m...

  2. A Multiple Data Fusion Approach to Wheel Slip Control for Decentralized Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Dejun Yin

    2017-04-01

    Full Text Available Currently, active safety control methods for cars, i.e., the antilock braking system (ABS, the traction control system (TCS, and electronic stability control (ESC, govern the wheel slip control based on the wheel slip ratio, which relies on the information from non-driven wheels. However, these methods are not applicable in the cases without non-driven wheels, e.g., a four-wheel decentralized electric vehicle. Therefore, this paper proposes a new wheel slip control approach based on a novel data fusion method to ensure good traction performance in any driving condition. Firstly, with the proposed data fusion algorithm, the acceleration estimator makes use of the data measured by the sensor installed near the vehicle center of mass (CM to calculate the reference acceleration of each wheel center. Then, the wheel slip is constrained by controlling the acceleration deviation between the actual wheel and the reference wheel center. By comparison with non-control and model following control (MFC cases in double lane change tests, the simulation results demonstrate that the proposed control method has significant anti-slip effectiveness and stabilizing control performance.

  3. Finite element analysis of rail-wheel interaction

    International Nuclear Information System (INIS)

    Rahman, F.; Kharlamov, Y.A.; Islam, S.; Khan, A.A.

    2006-01-01

    Damage mechanisms such as surface cracks, plastic deformation and wear can significantly reduce the service life of railway track and rolling stock. They also have a negative impact on the rolling noise as well as: on the riding comfort. A proper understanding of these mechanisms requires a detailed knowledge of physical interaction between wheel and rail. Furthermore, demands for higher train speeds and increased axle loads implies that the consequences of larger contact. forces between wheel and rail must be thoroughly investigated. Two methods have traditionally been used to investigate the rail-wheel contact, that is the Hertz analytical method and simplified numerical method based on the boundary element (BE) method. These methods rely on a half-space assumption and a linear material model. This paper presents that to overcome these limitations, a tool for FE-based quasistatic wheel-rail contact simulations has been developed. The tool is a library of ANSYS macro routines for configuring, meshing and loading of a parametric wheel-rail model. The meshing is based on measured wheel and rail profiles. The wheel and rail materials in the contact region are treated as elastic-plastic with kinematic hardening. By controlling the values of the configuration parameters, representations of various driving cases can be generated. The quasi-static loads are obtained from train motion. Interaction phenomena such as rolling, spinning and sidling can be included. The modeling tool and a methodology are described in the presented paper. Significant differences in the calculated state between the FE solution and the traditional approaches can be observed. These differences are most significant in situations with flange contact. (author)

  4. Electric wheel hub motor; Elektrischer Radnabenmotor

    Energy Technology Data Exchange (ETDEWEB)

    Groeninger, Michael; Kock, Alexander [IFAM Bremen (Germany); Horch, Felix [IFAM Bremen (Germany). Komponentenentwicklung; Pleteit, Hermann [IFAM Bremen (Germany). Abt. Giessereitechnologie und Komponentenentwicklung

    2012-02-15

    The bundled competences of the participating Fraunhofer Institutes have made it possible to develop a wheel hub motor that has essentially overcome currently existing technical hurdles, enabling its use in a vehicle. In addition to direct technical challenges such as sealing against external influences, high bearing stiffness requirements, necessary high torque densities and simple integration in the chassis, the safety aspects required by modern vehicles were also taken into account. A drive system that guarantees safe driving states, even in the case of malfunction, was developed through the combination of recuperative braking with a classic mechanical braking system and redundant motor design. (orig.)

  5. Proposal to use vibration analysis steering components and car body to monitor, for example, the state of unbalance wheel

    Science.gov (United States)

    Janczur, R.

    2016-09-01

    The results of road tests of car VW Passat equipped with tires of size 195/65 R15, on the influence of the unbalancing front wheel on vibration of the parts of steering system, steering wheel and the body of the vehicle have been presented in this paper. Unbalances wheels made using weights of different masses, placed close to the outer edge of the steel rim and checked on the machine Hunter GSP 9700 for balancing wheels. The recorded waveforms vibration steering components and car body, at different constant driving speeds, subjected to spectral analysis to determine the possibility of isolating vibration caused by unbalanced wheel in various states and coming from good quality asphalt road surface. The results were discussed in terms of the possibility of identifying the state of unbalancing wheels and possible changes in radial stiffness of the tire vibration transmitted through the system driving wheel on the steering wheel. Vibration analysis steering components and car body, also in the longitudinal direction, including information from the CAN bus of the state of motion of the car, can be used to monitor the development of the state of unbalance wheel, tire damage or errors shape of brake discs or brake drums, causing pulsations braking forces.

  6. Effects of Non-Driving Related Task Modalities on Takeover Performance in Highly Automated Driving.

    Science.gov (United States)

    Wandtner, Bernhard; Schömig, Nadja; Schmidt, Gerald

    2018-04-01

    Aim of the study was to evaluate the impact of different non-driving related tasks (NDR tasks) on takeover performance in highly automated driving. During highly automated driving, it is allowed to engage in NDR tasks temporarily. However, drivers must be able to take over control when reaching a system limit. There is evidence that the type of NDR task has an impact on takeover performance, but little is known about the specific task characteristics that account for performance decrements. Thirty participants drove in a simulator using a highly automated driving system. Each participant faced five critical takeover situations. Based on assumptions of Wickens's multiple resource theory, stimulus and response modalities of a prototypical NDR task were systematically manipulated. Additionally, in one experimental group, the task was locked out simultaneously with the takeover request. Task modalities had significant effects on several measures of takeover performance. A visual-manual texting task degraded performance the most, particularly when performed handheld. In contrast, takeover performance with an auditory-vocal task was comparable to a baseline without any task. Task lockout was associated with faster hands-on-wheel times but not altered brake response times. Results showed that NDR task modalities are relevant factors for takeover performance. An NDR task lockout was highly accepted by the drivers and showed moderate benefits for the first takeover reaction. Knowledge about the impact of NDR task characteristics is an enabler for adaptive takeover concepts. In addition, it might help regulators to make decisions on allowed NDR tasks during automated driving.

  7. Co-Design Based Lateral Motion Control of All-Wheel-Independent-Drive Electric Vehicles with Network Congestion

    Directory of Open Access Journals (Sweden)

    Wanke Cao

    2017-10-01

    Full Text Available All-wheel-independent-drive electric vehicles (AWID-EVs have considerable advantages in terms of energy optimization, drivability and driving safety due to the remarkable actuation flexibility of electric motors. However, in their current implementations, various real-time data in the vehicle control system are exchanged via a controller area network (CAN, which causes network congestion and network-induced delays. These problems could lead to systemic instability and make the system integration difficult. The goal of this paper is to provide a design methodology that can cope with all these challenges for the lateral motion control of AWID-EVs. Firstly, a continuous-time model of an AWID-EV is derived. Then an expression for determining upper and lower bounds on the delays caused by CAN is presented and with which a discrete-time model of the closed-loop CAN system is derived. An expression on the bandwidth utilization is introduced as well. Thirdly, a co-design based scheme combining a period-dependent linear quadratic regulator (LQR and a dynamic period scheduler is designed for the resulting model and the stability criterion is also derived. The results of simulations and hard-in-loop (HIL experiments show that the proposed methodology can effectively guarantee the stability of the vehicle lateral motion control while obviously declining the network congestion.

  8. Hand on the wheel, mind on the mobile: an analysis of social factors contributing to texting while driving.

    Science.gov (United States)

    Seiler, Steven J

    2015-02-01

    In an era defined by social technology, mobile phones provide constant connection to others. However, they also present a very dangerous situation when people choose to use their mobile phones while driving. In particular, exchanging text messages while driving has resulted in numerous accidents and fatalities. The purpose of this study is to examine social factors that lead people to text while driving. Specifically, using a multivariate logistic regression analysis of data from a 2010 survey by the Pew Research Center, variables for general mobile talk, driving while talking on a mobile, using the Internet on a mobile, sexting, and various motivations for texting were examined to determine factors that increase the likelihood of texting while driving. The findings suggest that people engage in mobile multiplexing (i.e., communication using two or more media on the mobile) while driving. Additionally, exchanging text messages in public, and consequently texting while driving, has become normalized. Furthermore, people are socialized into such behaviors through observing others texting while driving and using a mobile recklessly while driving. Finally, a number of motivations for texting were found to increase the likelihood of texting while driving significantly. Ultimately, the author contends that texting while driving has become a cultural artifact in the United States, which conflicts with driver safety as well as laws prohibiting texting while driving. The findings of this study could inform future awareness campaigns and technology developers to help establish a safer driving environment within the multitasking culture.

  9. Opportunity's View After Drive on Sol 1806

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 60.86 meters (200 feet) on the 1,806th Martian day, or sol, of Opportunity's surface mission (Feb. 21, 2009). North is at the center; south at both ends. Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Engineers designed the Sol 1806 drive to be driven backwards as a strategy to redistribute lubricant in the rovers wheels. The right-front wheel had been showing signs of increased friction. The rover's position after the Sol 1806 drive was about 2 kilometer (1.2 miles) south southwest of Victoria Crater. Cumulative odometry was 14.74 kilometers (9.16 miles) since landing in January 2004, including 2.96 kilometers (1.84 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a cylindrical projection with geometric seam correction.

  10. Wheels Optimization and Vision Control of Omni-directional Mobile Microrobot

    Directory of Open Access Journals (Sweden)

    Jianghao Li

    2008-06-01

    Full Text Available This paper presents a millimeters scale omni-directional mobile microrobot with special dual-wheel structure. The microrobot was actuated by three electromagnetic micromotors of 2mm diameter. Dynamic analysis of translational and steering movements presented the relationship between the sizes of the dual-wheel structure and the output torque of the micromotor. Genetic algorithm (GA was employed to optimize the dual-wheel's sizes for reducing the unnecessary torque consumption and improving the driving ability of the microrobot. A computer vision system contained two sets of feedback control is devised for the microrobot. Torque self-balance and current-limiting control approach are presented to ensure the accuracy of step movement. Experiment results demonstrate the feasibility of these concepts.

  11. Direct Yaw-Moment Control of All-Wheel-Independent-Drive Electric Vehicles with Network-Induced Delays through Parameter-Dependent Fuzzy SMC Approach

    Directory of Open Access Journals (Sweden)

    Wanke Cao

    2017-01-01

    Full Text Available This paper investigates the robust direct yaw-moment control (DYC through parameter-dependent fuzzy sliding mode control (SMC approach for all-wheel-independent-drive electric vehicles (AWID-EVs subject to network-induced delays. AWID-EVs have obvious advantages in terms of DYC over the traditional centralized-drive vehicles. However it is one of the most principal issues for AWID-EVs to ensure the robustness of DYC. Furthermore, the network-induced delays would also reduce control performance of DYC and even deteriorate the EV system. To ensure robustness of DYC and deal with network-induced delays, a parameter-dependent fuzzy sliding mode control (FSMC method based on the real-time information of vehicle states and delays is proposed in this paper. The results of cosimulations with Simulink® and CarSim® demonstrate the effectiveness of the proposed controller. Moreover, the results of comparison with a conventional FSMC controller illustrate the strength of explicitly dealing with network-induced delays.

  12. Drowsy Driving: Asleep at the Wheel

    Science.gov (United States)

    ... For more warning signs visit American Academy of Sleep Medicine. How often do Americans fall asleep while driving? ... is Enough? Accessed October 19, 2015. Institute of Medicine. Sleep Disorders and Sleep Deprivation: An Unmet Public Health ...

  13. Wheel liner design for improved sound and structural performances

    Science.gov (United States)

    Oltean, Alexandru; Diaconescu, Claudiu; Tabacu, Ştefan

    2017-10-01

    Vehicle noise is composed mainly of wheel-road noise and noise from the power unit. At low speeds power unit noise dominates while at high speeds wheel-road noise dominates as wheel-road noise level increases approximately logarithmically with speed. The wheel liner is designed as a component of the vehicle that has a multiple role. It has to prevent the dirt or water from the road surface that are engaged by the wheel to access the engine/front bay. Same time it has the important role to reduce perceived noised in the passenger’s compartment that comes from the wheel-road interaction. Progress in plastic injection moulding technology allowed for new structures to be developed - nonwoven materials in combination with a PP based carrier structure which benefits from a cell structure caused by MuCell injection moulding. The results are light parts with increased sound absorption performances. An adapted combination of materials and production processes can provide the solution for stiff yet soundproofing structures valued for modern vehicles. Sound absorption characteristics of materials used for wheel liners applications were reported in this study. Different polypropylene and polyester fibre-based thermally bonded nonwovens varying in weight and thickness were investigated. Having as a background the performances of the nonwoven material the microcellular structure was part of the analysis. Acoustical absorptive behaviour was explained by analysing the results obtained using the impedance tube and correlating with the knowledge of materials structure.

  14. Analysis of self-oscillations of the wheeled vehicle model when driving on a straight-line segment of the overpass

    Directory of Open Access Journals (Sweden)

    Sakhno V.P.

    2016-08-01

    Full Text Available There is the problem of traffic congestion of large cities of Ukraine. The introduction of the monorail will solve this problem. To ensure the comfort and safety of the transport of passengers it is proposed to investigate the lateral stability of this type of transportation, namely, to consider the question of self-oscillations. An approximate analysis of the amplitudes of oscillation of the model "one-wheeled" vehicle when driving on a straight-line segment of the overpass was performed. The diagram of the amplitudes of the oscillation system, which is received when changing the longitudinal speed of the crew allows us to estimate the influence of structural parameters of the system on the boundary of oscillatory instability and the amplitude of oscillation occurring. Rational selection of parameters of the transverse stiffness of the guide wheel module according to this method is consistent with the previously obtained research results. On the basis of the offered analytically-numerical method it is proved that rational choice of design parameters of systems that enable sustainable movement in the range operating speed (the maximum constructional speed of V = 140 km/h, moreover, security buckling when exceeding this speed. The amplitude of oscillation in excess of a critical value of the velocity parameter increases monotonically and does not exceed 3°, with V = 280 km/h.

  15. Novel Straight and Circular Road Driving Control of Electric Power Assisted Wheelchair Based on Fuzzy Algorithm

    Science.gov (United States)

    Seki, Hirokazu; Tadakuma, Susumu

    This paper describes a novel straight and circular road driving control scheme for electric power assisted wheelchairs. “Electric power assisted wheelchair” which assists the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the performance of the straight and circular road driving must be further improved because the two wheels drive independently. This paper proposes a novel driving control scheme based on fuzzy algorithm to realize the stable and reliable driving on straight and circular roads. The suitable assisted torque of the right and left wheels is determined by fuzzy algorithm based on the posture angular velocity of the wheelchair and the human input torque proportion of the right and left wheels. Some experiments on the practical roads show the effectiveness of the proposed control system.

  16. Analysis of wheel speed vibrations for road friction classification

    NARCIS (Netherlands)

    Schmeitz, A.J.C.; Alirezaei, M.

    2016-01-01

    With higher level of vehicle automation, it becomes increasingly important to know the maximum possible tyre forces during normal driving. An interesting method in this respect is estimating the tyre-road friction from the resonance in the wheel speed signal, excited by road roughness. A simulation

  17. On Optimizing Steering Performance of Multi-axle Vehicle Based on Driving Force Control

    Directory of Open Access Journals (Sweden)

    Wu Zhicheng

    2017-01-01

    Full Text Available The steering performance of multi-axle vehicle with independent driving system is affected by the distribution of the wheel driving force. A nonlinear vehicle dynamics model including magic formula tire model for describing 11 DoF four-axle vehicle with dual-front-axle-steering (DFAS system was presented. The influence of different driving force distribution scheme on the steering performance of the vehicle was analyzed. A control strategy for improving the steady response and transient response of the vehicle steering is proposed. The results show: For the steady response, setting different drive force for internal and external wheels according to the actual steering characteristics of the vehicle can effectively improve its steering characteristics; For the transient response, adopting the zero sideslip angle control strategy and using the PID control algorithm to control the driving force of the outside wheel of tear-two-axle, under angle step input, the vehicle sideslip angle can quickly stabilize to 0 and yaw rate also significantly decreases.

  18. Teen Drinking and Driving – What You Need to Know

    Centers for Disease Control (CDC) Podcasts

    This podcast is based on the October 2012 CDC Vital Signs report. It’s illegal and dangerous for teens to drink any alcohol and then drive. Still, one in ten high school teens drank and got behind the wheel in 2011. A parent-teen driving agreement is a good way for parents to help keep young drivers safe behind the wheel.

  19. Bright Soil Churned by Spirit's Sol 1861 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit drove 22.7 meters (74 feet) toward the southwest on the 1,861st Martian day, or sol, of Spirit's mission on Mars (March 28, 2009). After the drive, the rover took this image with its front hazard-avoidance camera, looking back at the tracks from the drive. As usual since losing the use of its right-front wheel in 2006, Spirit drove backwards. The immobile right-front wheel churned up a long stripe of bright soil during this drive. Where Spirit has found such bright soil in the past, subsequent analysis of the composition found concentrations of sulfur or silica that testified to past action of water at the site. When members of the rover team saw the large quantity of bright soil exposed by the Sol 1861 drive, they quickly laid plans to investigate the composition with Spirit's alpha particle X-ray spectrometer. The Sol 1861 drive took the rover past the northwest corner of the low plateau called 'Home Plate,' making progress on a route around the western side of Home Plate. The edge of Home Plate forms the horizon on the right side of this image. Husband Hill is on the horizon on the left side. For scale, the parallel rover wheel tracks are about 1 meter (40 inches) apart. The rover's hazard-avoidance cameras take 'fisheye' wide-angle images.

  20. Modelling of a mecanum wheel taking into account the geometry of road rollers

    Science.gov (United States)

    Hryniewicz, P.; Gwiazda, A.; Banaś, W.; Sękala, A.; Foit, K.

    2017-08-01

    During the process planning in a company one of the basic factors associated with the production costs is the operation time for particular technological jobs. The operation time consists of time units associated with the machining tasks of a workpiece as well as the time associated with loading and unloading and the transport operations of this workpiece between machining stands. Full automation of manufacturing in industry companies tends to a maximal reduction in machine downtimes, thereby the fixed costs simultaneously decreasing. The new construction of wheeled vehicles, using Mecanum wheels, reduces the transport time of materials and workpieces between machining stands. These vehicles have the ability to simultaneously move in two axes and thus more rapid positioning of the vehicle relative to the machining stand. The Mecanum wheel construction implies placing, around the wheel free rollers that are mounted at an angle 450, which allow the movement of the vehicle not only in its axis but also perpendicular thereto. The improper selection of the rollers can cause unwanted vertical movement of the vehicle, which may cause difficulty in positioning of the vehicle in relation to the machining stand and the need for stabilisation. Hence the proper design of the free rollers is essential in designing the whole Mecanum wheel construction. It allows avoiding the disadvantageous and unwanted vertical vibrations of a whole vehicle with these wheels. In the article the process of modelling the free rollers, in order to obtain the desired shape of unchanging, horizontal trajectory of the vehicle is presented. This shape depends on the desired diameter of the whole Mecanum wheel, together with the road rollers, and the width of the drive wheel. Another factor related with the curvature of the trajectory shape is the length of the road roller and its diameter decreases depending on the position with respect to its centre. The additional factor, limiting construction of

  1. Vehicle wheel drag coefficient in relation to travelling velocity - CFD analysis

    Science.gov (United States)

    Leśniewicz, P.; Kulak, M.; Karczewski, M.

    2016-10-01

    In order to understand the aerodynamic losses associated with a rotating automobile wheel, a detailed characteristics of the drag coefficient in relation to the applied velocity are necessary. Single drag coefficient value is most often reported for the commercially available vehicles, much less is revealed about the influence of particular car components on the energy consumption in various driving cycles. However, detailed flow potential losses determination is desired for performance estimation. To address these needs, the numerical investigation of an isolated wheel is proposed herein.

  2. Opportunity's View After Drive on Sol 1806 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 60.86 meters (200 feet) on the 1,806th Martian day, or sol, of Opportunity's surface mission (Feb. 21, 2009). North is at the center; south at both ends. Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Engineers designed the Sol 1806 drive to be driven backwards as a strategy to redistribute lubricant in the rovers wheels. The right-front wheel had been showing signs of increased friction. The rover's position after the Sol 1806 drive was about 2 kilometer (1.2 miles) south southwest of Victoria Crater. Cumulative odometry was 14.74 kilometers (9.16 miles) since landing in January 2004, including 2.96 kilometers (1.84 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a polar projection with geometric seam correction.

  3. Opportunity's View After Drive on Sol 1806 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 60.86 meters (200 feet) on the 1,806th Martian day, or sol, of Opportunity's surface mission (Feb. 21, 2009). North is at the center; south at both ends. Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Engineers designed the Sol 1806 drive to be driven backwards as a strategy to redistribute lubricant in the rovers wheels. The right-front wheel had been showing signs of increased friction. The rover's position after the Sol 1806 drive was about 2 kilometer (1.2 miles) south southwest of Victoria Crater. Cumulative odometry was 14.74 kilometers (9.16 miles) since landing in January 2004, including 2.96 kilometers (1.84 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a vertical projection with geometric seam correction.

  4. Driving performance at lateral system limits during partially automated driving.

    Science.gov (United States)

    Naujoks, Frederik; Purucker, Christian; Wiedemann, Katharina; Neukum, Alexandra; Wolter, Stefan; Steiger, Reid

    2017-11-01

    This study investigated driver performance during system limits of partially automated driving. Using a motion-based driving simulator, drivers encountered different situations in which a partially automated vehicle could no longer safely keep the lateral guidance. Drivers were distracted by a non-driving related task on a touch display or driving without an additional secondary task. While driving in partially automated mode drivers could either take their hands off the steering wheel for only a short period of time (10s, so-called 'Hands-on' variant) or for an extended period of time (120s, so-called 'Hands-off' variant). When the system limit was reached (e.g., when entering a work zone with temporary lines), the lateral vehicle control by the automation was suddenly discontinued and a take-over request was issued to the drivers. Regardless of the hands-off interval and the availability of a secondary task, all drivers managed the transition to manual driving safely. No lane exceedances were observed and the situations were rated as 'harmless' by the drivers. The lack of difference between the hands-off intervals can be partly attributed to the fact that most of the drivers kept contact to the steering wheel, even in the hands-off condition. Although all drivers were able to control the system limits, most of them could not explain why exactly the take-over request was issued. The average helpfulness of the take-over request was rated on an intermediate level. Consequently, providing drivers with information about the reason for a system limit can be recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Soft Legged Wheel-Based Robot with Terrestrial Locomotion Abilities

    Directory of Open Access Journals (Sweden)

    Ali Sadeghi

    2016-12-01

    Full Text Available In recent years robotics has been influenced by a new approach, soft-robotics, bringing the idea that safe interaction with user and more adaptation to the environment can be achieved by exploiting easily deformable materials and flexible components in the structure of robots. In 2016, the soft-robotics community has promoted a new robotics challenge, named RoboSoft Grand Challenge, with the aim of bringing together different opinions on the usefulness and applicability of softness and compliancy in robotics. In this paper we describe the design and implementation of a terrestrial robot based on two soft legged wheels. The tasks predefined by the challenge were set as targets in the robot design, which finally succeeded to accomplish all the tasks. The wheels of the robot can passively climb over stairs and adapt to slippery grounds using two soft legs embedded in their structure. The soft legs, fabricated by integration of soft and rigid materials and mounted on the circumference of a conventional wheel, succeed to enhance its functionality and easily adapt to unknown grounds. The robot has a semi stiff tail that helps in the stabilization and climbing of stairs. An active wheel is embedded at the extremity of the tail in order to increase the robot maneuverability in narrow environments. Moreover two parallelogram linkages let the robot to reconfigure and shrink its size allowing entering inside gates smaller than its initial dimensions.

  6. A novel instrumented multipeg running wheel system, Step-Wheel, for monitoring and controlling complex sequential stepping in mice.

    Science.gov (United States)

    Kitsukawa, Takashi; Nagata, Masatoshi; Yanagihara, Dai; Tomioka, Ryohei; Utsumi, Hideko; Kubota, Yasuo; Yagi, Takeshi; Graybiel, Ann M; Yamamori, Tetsuo

    2011-07-01

    Motor control is critical in daily life as well as in artistic and athletic performance and thus is the subject of intense interest in neuroscience. Mouse models of movement disorders have proven valuable for many aspects of investigation, but adequate methods for analyzing complex motor control in mouse models have not been fully established. Here, we report the development of a novel running-wheel system that can be used to evoke simple and complex stepping patterns in mice. The stepping patterns are controlled by spatially organized pegs, which serve as footholds that can be arranged in adjustable, ladder-like configurations. The mice run as they drink water from a spout, providing reward, while the wheel turns at a constant speed. The stepping patterns of the mice can thus be controlled not only spatially, but also temporally. A voltage sensor to detect paw touches is attached to each peg, allowing precise registration of footfalls. We show that this device can be used to analyze patterns of complex motor coordination in mice. We further demonstrate that it is possible to measure patterns of neural activity with chronically implanted tetrodes as the mice engage in vigorous running bouts. We suggest that this instrumented multipeg running wheel (which we name the Step-Wheel System) can serve as an important tool in analyzing motor control and motor learning in mice.

  7. Gamma counter shutter assembly

    International Nuclear Information System (INIS)

    Aday, R.W. Jr.; Barber, D.G.

    1976-01-01

    A shutter assembly for a radioactivity measuring apparatus is described having a sample counting chamber, the assembly having a bulky solid lead cylinder with a sample access port extending therethrough for alignment with the sample chamber. The cylinder is rotated by a Geneva wheel arrangement having a drive wheel with a plurality of equi-angularly disposed pins perpendicular to the surface thereof engaging radially extending open-ended slots in a driven wheel secured to the lead cylinder for concurrent rotation therewith. The drive wheel is rotated at a constant speed with the driven wheel accelerating as a pin traverses the slot from the open end toward the driven wheel center and then decelerating as the pin traverses the reverse direction to provide precise positioning with adjacent pins engaging the open ends of adjacent slots in the stop position of the cylinder. 8 Claims, 3 Drawing Figures

  8. The use of a running wheel to measure activity in rodents: relationship to energy balance, general activity, and reward.

    Science.gov (United States)

    Novak, Colleen M; Burghardt, Paul R; Levine, James A

    2012-03-01

    Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems-including those related to the stress response, mood, and reward, and those responsive to growth factors-that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. The use of a running wheel to measure activity in rodents: Relationship to energy balance, general activity, and reward

    Science.gov (United States)

    Levine, James A.

    2015-01-01

    Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems—including those related to the stress response, mood, and reward, and those responsive to growth factors—that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. PMID:22230703

  10. Distributed and self-adaptive vehicle speed estimation in the composite braking case for four-wheel drive hybrid electric car

    Science.gov (United States)

    Zhao, Z.-G.; Zhou, L.-J.; Zhang, J.-T.; Zhu, Q.; Hedrick, J.-K.

    2017-05-01

    Considering the controllability and observability of the braking torques of the hub motor, Integrated Starter Generator (ISG), and hydraulic brake for four-wheel drive (4WD) hybrid electric cars, a distributed and self-adaptive vehicle speed estimation algorithm for different braking situations has been proposed by fully utilising the Electronic Stability Program (ESP) sensor signals and multiple powersource signals. Firstly, the simulation platform of a 4WD hybrid electric car was established, which integrates an electronic-hydraulic composited braking system model and its control strategy, a nonlinear seven degrees-of-freedom vehicle dynamics model, and the Burckhardt tyre model. Secondly, combining the braking torque signals with the ESP signals, self-adaptive unscented Kalman sub-filter and main-filter adaptable to the observation noise were, respectively, designed. Thirdly, the fusion rules for the sub-filters and master filter were proposed herein, and the estimation results were compared with the simulated value of a real vehicle speed. Finally, based on the hardware in-the-loop platform and by picking up the regenerative motor torque signals and wheel cylinder pressure signals, the proposed speed estimation algorithm was tested under the case of moderate braking on the highly adhesive road, and the case of Antilock Braking System (ABS) action on the slippery road, as well as the case of ABS action on the icy road. Test results show that the presented vehicle speed estimation algorithm has not only a high precision but also a strong adaptability in the composite braking case.

  11. The mathematical model for the investigation of different influence factors on the economic and ecological indicators of a wheel tractor

    Directory of Open Access Journals (Sweden)

    Zakharchuk V.I.

    2016-08-01

    Full Text Available To solve the problem of oil deficit and reduce emissions of harmful substances from exhaust gases of vehicles alternative motor fuels, including biodiesel may by used. Most of wheel tractors are used as technological transport in agriculture, industry and municipal services. The article aims to clarify the mathematical model to determine the effect of the type of fuel used wheeled tractors on its performance. The mathematical model of the system "operator-wheel tractor-road" for the design research impact type of fuel on harmful emissions and fuel consumption wheeled tractor, is used as technological transport during its movement for driving cycle. Driving cycle showed main modes of motion there are acceleration, motion with constant speed and deceleration. The mathematical model allows to accurately consider peculiarities of the wheel tractor as the vehicle and engine describing its characteristics by polinomial dependencies. In mathematical models specified polynomial dependences that describe the fuel supply cycle indicated torque, fuel consumption and concentrations of main harmful substances in the exhaust gases of diesel during operation on diesel and biodiesel.

  12. Preliminary Design of Reluctance Motors for Light Electric Vehicles Driving

    Directory of Open Access Journals (Sweden)

    TRIFA, V.

    2009-02-01

    Full Text Available The paper presents the aspects regarding FEM analysis of a reluctant motor for direct driving of the light electric vehicles. The reluctant motor take into study is of special construction suitable for direct drive of a light electric vehicle. It is an inverse radial reluctant motor, with a fixed stator mounted on front wheel shaft and an external toothed rotor fixed on the front wheel itself. A short presentation of preliminary design is continued with the FEM analysis in order to provide the optimal geometry of the motor and adequate windings.

  13. Grinding performance evaluation of porous composite-bonded CBN wheels for Inconel 718

    Directory of Open Access Journals (Sweden)

    Chen Zhenzhen

    2014-08-01

    Full Text Available For high-efficiency grinding of difficult-to-cut materials such as titanium and nickel alloys, a high porosity is expected and also a sufficient mechanical strength to satisfy the function. However, the porosity increase is a disadvantage to the mechanical strength. As a promising pore forming agent, alumina bubbles are firstly induced into the abrasive layer to fabricate porous cubic boron nitride (CBN wheels. When the wheel porosity reaches 45%, the bending strength is still high up to 50 MPa with modified orderly pore distribution. A porous CBN wheel was fabricated with a total porosity around 30%. The grinding performance of the porous composite-bonded CBN wheel was evaluated in terms of specific force, specific grinding energy, and grinding temperature, which were better than those of the vitrified one under the same grinding conditions. Compared to the vitrified CBN wheel, clear straight cutting grooves and less chip adhesion are observed on the ground surface and there is also no extensive loading on the wheel surface after grinding.

  14. A novel multi-drive electric vehicle system control based on multi-input multi-output PID controller

    Directory of Open Access Journals (Sweden)

    Gasbaoui Brahim

    2012-01-01

    Full Text Available In-wheel-motor drive electric vehicle (EV is an innovative configuration of the modern EV, in which each wheel is driven individually by an electric motor. The classical traction motor control called the Independent Machine Control Structure (IMCS using a PID speed controller presents major inconveniences in modern EV safety, when the proposed control can not ensure stability of the EV with differing road topology and variations of speed. A new approach is proposed for a control of a two-in-wheel-motor drive EV, called the Maximum Control Structure MCS. This is based on a multivariable PID (MIMO-PID strategy, which is employed to estimate the linear speed error of each of the two back driving wheels, when the error of each wheel is taken into account in the other speed control computations. Simulation results show that the new control system presents increased safety for the EVs compared with the IMCS strategy and can maintain the error slip rate within the optimal range, ensuring the stability of the vehicle either in a straight or a curved line.

  15. Stability Simulation of a Vehicle with Wheel Active Steering

    Directory of Open Access Journals (Sweden)

    Brabec Pavel

    2016-01-01

    Full Text Available This paper deals with the possibility of increasing the vehicle driving stability at a higher speed. One of the ways how to achieve higher stability is using the 4WS system. Mathematical description of vehicle general movement is a very complex task. For simulation, models which are aptly simplified are used. For the first approach, so-called single-truck vehicle model (often linear is usually used. For the simulation, we have chosen to extend the model into a two-truck one, which includes the possibility to input more vehicle parameters. Considering the 4WS system, it is possible to use a number of potential regulations. In our simulation model, the regulation system with compound coupling was used. This type of regulation turns the rear wheels depending on the input parameters of the system (steering angle of the front wheels and depending on the output moving quantities of the vehicle, most frequently the yaw rate. Criterion for compensation of lateral deflection centre of gravity angle is its zero value, or more precisely the zero value of its first-order derivative. Parameters and set-up of the simulation model were done in conjunction with the dSAPACE software. Reference performances of the vehicle simulation model were made through the defined manoeuvres. But the simulation results indicate that the rear-wheels steering can have a positive effect on the vehicle movement stability, especially when changing the driving direction at high speed.

  16. Butt pressure welding of wheels from vehicles consisting of steel and aluminium; Pressstumpfschweissen von Fahrzeugraedern aus Stahl und Aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Grobelin, K. [Hess Engineering AG, Frauenfeld (Switzerland)

    2001-07-01

    Every year in Europe 35 million wheels for vehicles are produced. Most of them are wheels consisting of metal tapes, both of steel and of aluminium alloys. The manufacturing of wheels is explained, in detail the method known as DC upset welding used for butt joints of wheel-rims. The engaged machinery, the specials of welding various materials, the limits of the method, and the quality assurance are discussed. Advantages of the applied method are joints of first-class quality, high productivity, energy saving and environmental cleanness. (orig.)

  17. Engage me in taking care of my heart’: a grounded theory study on patient–cardiologist relationship in the hospital management of heart failure

    Science.gov (United States)

    Barello, Serena; Graffigna, Guendalina; Vegni, Elena; Savarese, Mariarosaria; Lombardi, Federico; Bosio, A Claudio

    2015-01-01

    Objective In approaching the study and practice of heart failure (HF) management, authors recognise that the patient–doctor relationship has a central role in engaging patients in their care. This study aims at identifying the features and the levers of HF patient engagement and suggestions for orienting clinical encounters. Design Using a grounded theory approach, we conducted 22 in-depth interviews (13 patients with HF, 5 physicians and 4 caregivers). Data were collected and analysed using open, axial and selective coding procedures according to the grounded theory principles. Settings All interviews were conducted in an office in a university hospital located in a metropolitan area of Milan, Italy. Participants The data comprised a total of 22 patient, hospital cardiologist and caregiver interviews. Patients aged ≥18 years with New York Heart Association (NYHA) Functional Class of II or III were eligible to take part. Patients were recruited primarily through their referral cardiologist. Results The HF patient engagement process develops in four main phases that are characterised by different patients’ emotional, cognitive and behavioural dynamics that contribute to shape the process of a patient's meaning making towards health and illness regarding their care. The emerging model illustrates that HF patient engagement entails a meaning-making process enacted by the patient after the critical event. This implies patients’ ability to give sense to their care experience and to their disease, symptomatology and treatments, and their changes along their illness course. Doctors are recognised as crucial in fostering patients’ engagement along all the phases of the process as they contribute to providing patients with self-continuity and give new meaning to their illness experience. Conclusions This study identifies the core experiential domains and the main levers involved in driving patients with HF to effectively engage in their disease management. The

  18. A fly-wheel drive with controlled-torque clutch for a reactors cooling circuit pumps; Entrainement des pompes du circuit de refrigeration d'un reacteur par volant a embrayage sous couple controle

    Energy Technology Data Exchange (ETDEWEB)

    Riettini, A [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1964-10-15

    After a theoretical study on the slowing down of a centrifugal pump, the motion equations have been checked by means of experimental tests. In order to have important slowing down times (which is the case of the cooling pumps of a research reactor) it is necessary to add a fly-wheel. To prevent troubles when starting, a block pump-fly-wheel with clutch under controlled torque was developed. It is so possible to start the fly-wheel progressively without increasing too much power of the driving motor. (author) [French] Apres une etude theorique sur le mouvement de ralentissement d'une pompe centrifuge, les equations du mouvement ont ete verifiees par des essais pratiques. Pour obtenir des temps de ralentissement importants (cas des pompes de refrigeration d'un reacteur de recherche) il est necessaire d'y adjoindre un volant d'inertie. Pour eviter les inconvenients au demarrage, on a etudie un ensemble pompe-volant avec embrayage sous couple controle. Cette solution permet de lancer progressivement le volant sans augmentation appreciable de la puissance du moteur d'entrainement. (auteur)

  19. Teen Drinking and Driving – What You Need to Know PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    This 60 second public service announcement is based on the October 2012 CDC Vital Signs report. It’s illegal and dangerous for teens to drink any alcohol and then drive. Still, one in ten high school teens drank and got behind the wheel in 2011. A parent-teen driving agreement is a good way for parents to help keep young drivers safe behind the wheel.

  20. Development of a Hardware-In-Loop (HIL Simulator for Spacecraft Attitude Control Using Momentum Wheels

    Directory of Open Access Journals (Sweden)

    Dohee Kim

    2008-12-01

    Full Text Available In this paper, a Hardware-In-the-Loop simulator to simulate attitude control of spacecraft using momentum wheels is developed. The simulator consists of a spherical air bearing system allowing rotation and tilt in all three axes, three momentum wheels for actuation, and an AHRS (Attitude Heading Reference System. The simulator processes various types of data in PC104 and wirelessly communicates with a host PC using TCP/IP protocol. A simple low-cost momentum wheel assembly set and its drive electronics are also developed. Several experiments are performed to test the performance of the momentum wheels. For the control performance test of the simulator, a PID controller is implemented. The results of experimental demonstrations confirm the feasibility and validity of the Hardware-In-the-Loop simulator developed in the current study.

  1. A Ferris Wheel Accident at a Movable Amusement Park.

    Science.gov (United States)

    Cho, Young-Jin; Ji, Hong-Keun; Moon, Byung-Sun; Park, Ha-Sun; Goh, Jae-Mo; Park, Nam-Kyu; Choi, Don-Mook

    2017-05-01

    This study presented a Ferris wheel accident case. A Ferris wheel is composed of many parts, and the outmost ring of it is assembled using a lock pin. This accident occurred because the lock pin caught the door of a gondola and the gondola overturned. Five of the seven passengers in the gondola fell to the ground, along with the gondola's viewing window. The investigation revealed that the gondola became stuck when its door was caught by a lock pin at the Ferris wheel's three o'clock position. The contact between the door and the lock pin was due to a structural problem: There was not enough space allotted between the door and the lock pin. Therefore, if a passenger pushed on the gondola's door, the potential existed for contact between the door and the lock pin. © 2016 American Academy of Forensic Sciences.

  2. Drowsy Driver Detection via Steering Wheel

    Directory of Open Access Journals (Sweden)

    Herlina ABDUL RAHIM

    2010-09-01

    Full Text Available The main purpose of this project is to produce a safety system especially for fatigue car driver so as to prevent from accidents. The statistic on road fatality shows that human error constitute of 64.84 % road accidents fatality and 17.4 % due to technical factors. These systems encompassed the approach of hand pressure applied on the steering wheel. The steering will be installed with pressure sensors. At the same time these sensors can be used to measure gripping force while driving.

  3. Integrated Traction Control Strategy for Distributed Drive Electric Vehicles with Improvement of Economy and Longitudinal Driving Stability

    Directory of Open Access Journals (Sweden)

    Xudong Zhang

    2017-01-01

    Full Text Available This paper presents an integrated traction control strategy (ITCS for distributed drive electric vehicles. The purpose of the proposed strategy is to improve vehicle economy and longitudinal driving stability. On high adhesion roads, economy optimization algorithm is applied to maximize motors efficiency by means of the optimized torque distribution. On low adhesion roads, a sliding mode control (SMC algorithm is implemented to guarantee the wheel slip ratio around the optimal slip ratio point to make full use of road adhesion capacity. In order to avoid the disturbance on slip ratio calculation due to the low vehicle speed, wheel rotational speed is taken as the control variable. Since the optimal slip ratio varies according to different road conditions, Bayesian hypothesis selection is utilized to estimate the road friction coefficient. Additionally, the ITCS is designed for combining the vehicle economy and stability control through three traction allocation cases: economy-based traction allocation, pedal self-correcting traction allocation and inter-axles traction allocation. Finally, simulations are conducted in CarSim and Matlab/Simulink environment. The results show that the proposed strategy effectively reduces vehicle energy consumption, suppresses wheels-skid and enhances the vehicle longitudinal stability and dynamic performance.

  4. Improved infrared-sensing running wheel systems with an effective exercise activity indicator.

    Science.gov (United States)

    Chen, Chi-Chun; Chang, Ming-Wen; Chang, Ching-Ping; Chang, Wen-Ying; Chang, Shin-Chieh; Lin, Mao-Tsun; Yang, Chin-Lung

    2015-01-01

    This paper describes an infrared-sensing running wheel (ISRW) system for the quantitative measurement of effective exercise activity in rats. The ISRW system provides superior exercise training compared with commercially available traditional animal running platforms. Four infrared (IR) light-emitting diode/detector pairs embedded around the rim of the wheel detect the rat's real-time position; the acrylic wheel has a diameter of 55 cm and a thickness of 15 cm, that is, it is larger and thicker than traditional exercise wheels, and it is equipped with a rubber track. The acrylic wheel hangs virtually frictionless, and a DC motor with an axially mounted rubber wheel, which has a diameter of 10 cm, drives the acrylic wheel from the outer edge. The system can automatically train rats to run persistently. The proposed system can determine effective exercise activity (EEA), with the IR sensors (which are connected to a conventional PC) recording the rat exercise behavior. A prototype of the system was verified by a hospital research group performing ischemic stroke experiments on rats by considering middle cerebral artery occlusion. The experimental data demonstrated that the proposed system provides greater neuroprotection in an animal stroke model compared with a conventional treadmill and a motorized running wheel for a given exercise intensity. The quantitative exercise effectiveness indicator showed a 92% correlation between an increase in the EEA and a decrease in the infarct volume. This indicator can be used as a noninvasive and objective reference in clinical animal exercise experiments.

  5. Improved infrared-sensing running wheel systems with an effective exercise activity indicator.

    Directory of Open Access Journals (Sweden)

    Chi-Chun Chen

    Full Text Available This paper describes an infrared-sensing running wheel (ISRW system for the quantitative measurement of effective exercise activity in rats. The ISRW system provides superior exercise training compared with commercially available traditional animal running platforms. Four infrared (IR light-emitting diode/detector pairs embedded around the rim of the wheel detect the rat's real-time position; the acrylic wheel has a diameter of 55 cm and a thickness of 15 cm, that is, it is larger and thicker than traditional exercise wheels, and it is equipped with a rubber track. The acrylic wheel hangs virtually frictionless, and a DC motor with an axially mounted rubber wheel, which has a diameter of 10 cm, drives the acrylic wheel from the outer edge. The system can automatically train rats to run persistently. The proposed system can determine effective exercise activity (EEA, with the IR sensors (which are connected to a conventional PC recording the rat exercise behavior. A prototype of the system was verified by a hospital research group performing ischemic stroke experiments on rats by considering middle cerebral artery occlusion. The experimental data demonstrated that the proposed system provides greater neuroprotection in an animal stroke model compared with a conventional treadmill and a motorized running wheel for a given exercise intensity. The quantitative exercise effectiveness indicator showed a 92% correlation between an increase in the EEA and a decrease in the infarct volume. This indicator can be used as a noninvasive and objective reference in clinical animal exercise experiments.

  6. Teen Drinking and Driving – What You Need to Know

    Centers for Disease Control (CDC) Podcasts

    2012-10-02

    This podcast is based on the October 2012 CDC Vital Signs report. It’s illegal and dangerous for teens to drink any alcohol and then drive. Still, one in ten high school teens drank and got behind the wheel in 2011. A parent-teen driving agreement is a good way for parents to help keep young drivers safe behind the wheel.  Created: 10/2/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 10/2/2012.

  7. Extended driving impairs nocturnal driving performances.

    Directory of Open Access Journals (Sweden)

    Patricia Sagaspe

    Full Text Available Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3-5 am, 1-5 am and 9 pm-5 am on open highway. Fourteen young healthy men (mean age [+/-SD] = 23.4 [+/-1.7] years participated Inappropriate line crossings (ILC in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3-5 am driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05 for the intermediate (1-5 am driving session and by 4.0 (CI, 1.7 to 9.4; P<.001 for the long (9 pm-5 am driving session. Compared to the reference session (9-10 pm, the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001, 15.4 (CI, 4.6 to 51.5; P<.001 and 24.3 (CI, 7.4 to 79.5; P<.001, respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05 and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01. At night, extended driving impairs driving performances and therefore should be limited.

  8. Wheels, skills and thrills: a social marketing trial to reduce aggressive driving from young men in deprived areas.

    Science.gov (United States)

    Tapp, Alan; Pressley, Ashley; Baugh, Mike; White, Paul

    2013-09-01

    Young men from poorer backgrounds are associated with high road traffic collision levels. However, solving this problem has proven very difficult. Hence this paper summarises the findings of a UK government funded two-year trial of a cross-discipline intervention to reduce aggressive driving amongst this group. The intervention reported on here departed from traditional approaches such as fear appeals, stand-alone educational approaches, or punitive measures. Instead, the discipline of social marketing was used to provide overarching direction and structure for the trial, with a key focus on motivation and engagement. The project rested on a strong education and training platform and included a bespoke coaching programme, incentives, and an in-vehicle measurement and feedback device. The project had three development phases leading to the final trial. First, a literature and case study review identified possible design strategies. Second, these strategies were explored using primary research in the form of a qualitative inquiry. Third, a pre-trial design phase sought to introduce key components of the intervention to the trial cohort, retaining some flexibility before committing to the final design. Young males with a history of challenging behaviour (e.g. criminal records, driving convictions) from an economically deprived area within a UK city were recruited. Of 42 recruits, 23 successfully completed the trial. Behaviour changes were measured pre-, during and post-trial through a combination of driver performance data measured by in-vehicle data recorders (IVDRs), assessments of driving undertaken by trained observers, and self-assessment surveys and interviews with trial participants. Results indicate a significant average improvement in driving skills amongst participants who completed the trial. Given the difficulty in engaging and changing behaviour of this specific group, this is regarded as a significant finding. In summary the study provides an indication

  9. Wheels Optimization and Vision Control of Omni-directional Mobile Microrobot

    Directory of Open Access Journals (Sweden)

    Jianghao Li

    2008-11-01

    Full Text Available This paper presents a millimeters scale omni-directional mobile microrobot with special dual-wheel structure. The microrobot was actuated by three electromagnetic micromotors of 2mm diameter. Dynamic analysis of translational and steering movements presented the relationship between the sizes of the dual-wheel structure and the output torque of the micromotor. Genetic algorithm (GA was employed to optimize the dualwheel's sizes for reducing the unnecessary torque consumption and improving the driving ability of the microrobot. A computer vision system contained two sets of feedback control is devised for the microrobot. Torque self-balance and current-limiting control approach are presented to ensure the accuracy of step movement. Experiment results demonstrate the feasibility of these concepts.

  10. 'Engage me in taking care of my heart': a grounded theory study on patient-cardiologist relationship in the hospital management of heart failure.

    Science.gov (United States)

    Barello, Serena; Graffigna, Guendalina; Vegni, Elena; Savarese, Mariarosaria; Lombardi, Federico; Bosio, A Claudio

    2015-03-16

    In approaching the study and practice of heart failure (HF) management, authors recognise that the patient-doctor relationship has a central role in engaging patients in their care. This study aims at identifying the features and the levers of HF patient engagement and suggestions for orienting clinical encounters. Using a grounded theory approach, we conducted 22 in-depth interviews (13 patients with HF, 5 physicians and 4 caregivers). Data were collected and analysed using open, axial and selective coding procedures according to the grounded theory principles. All interviews were conducted in an office in a university hospital located in a metropolitan area of Milan, Italy. The data comprised a total of 22 patient, hospital cardiologist and caregiver interviews. Patients aged ≥18 years with New York Heart Association (NYHA) Functional Class of II or III were eligible to take part. Patients were recruited primarily through their referral cardiologist. The HF patient engagement process develops in four main phases that are characterised by different patients' emotional, cognitive and behavioural dynamics that contribute to shape the process of a patient's meaning making towards health and illness regarding their care. The emerging model illustrates that HF patient engagement entails a meaning-making process enacted by the patient after the critical event. This implies patients' ability to give sense to their care experience and to their disease, symptomatology and treatments, and their changes along their illness course. Doctors are recognised as crucial in fostering patients' engagement along all the phases of the process as they contribute to providing patients with self-continuity and give new meaning to their illness experience. This study identifies the core experiential domains and the main levers involved in driving patients with HF to effectively engage in their disease management. The model emerging from this study may help clinicians think in a fresh

  11. Mobile Business Retailing: Driving Experiential Learning on Campus

    Science.gov (United States)

    Fischbach, Sarah; Guerrero, Veronica

    2018-01-01

    Engaging students in the classroom is a struggle all faculty face especially in the age of modern technology. This article proposes a novel approach to engage and motivate students through the mobile business "on wheels" marketing concept. The growth in mobile business retailing (e.g., food trucks, mobile dog groomers, etc.) is an…

  12. Life-cycle analysis of energy and greenhouse gas emissions of automotive fuels in India: Part 1 – Tank-to-Wheel analysis

    International Nuclear Information System (INIS)

    Gupta, S.; Patil, V.; Himabindu, M.; Ravikrishna, R.V.

    2016-01-01

    As part of a two-part life cycle efficiency and greenhouse gas emission analysis for various automotive fuels in the Indian context, this paper presents the first part, i.e., Tank-to-Wheel analysis of various fuel/powertrain configurations for a subcompact passenger car. The Tank-to-Wheel analysis was applied to 28 fuel/powertrain configurations using fuels such as gasoline, diesel, compressed natural gas, liquefied petroleum gas and hydrogen with various conventional and hybrid electric powertrains. The gasoline-equivalent fuel economy and carbon dioxide emission results for individual fuel/powertrain configuration are evaluated and compared. It is found that the split hybrid configuration is best among hybrids as it leads to fuel economy improvement and carbon dioxide emissions reduction by 20–40% over the Indian drive cycle. Further, the engine efficiency, engine on-off time and regenerative braking energy assessment is done to evaluate the causes for higher energy efficiency of hybrid electric vehicles. The hybridization increases average engine efficiency by 10–60% which includes 19–23% of energy recovered at wheel through regenerative braking over the drive cycle. Overall, the Tank-to-Wheel energy use and efficiency results are evaluated for all fuel/powertrain configurations which show Battery Electric Vehicle, fuel cell vehicles and diesel hybrids are near and long term energy efficient vehicle configurations. - Highlights: • Tank-to-Wheel energy use & CO_2 emissions for subcompact car on Indian driving cycle. • Gasoline, diesel, CNG, LPG, hydrogen and electric vehicles are evaluated in this study. • First comprehensive Tank-to-Wheel analysis for India on small passenger car platform. • Parallel, series and split hybrid electric vehicles with various fuels are analysed.

  13. Effect of sleep deprivation on driving safety in housestaff.

    Science.gov (United States)

    Marcus, C L; Loughlin, G M

    1996-12-01

    Sleep deprivation is known to affect driving safety. Housestaff (HS) are routinely sleep-deprived when on call. We hypothesized that this would affect their driving. We therefore administered questionnaires regarding driving to 70 pediatric HS, who were on call every fourth night, and to 85 faculty members (FAC), who were rarely disturbed at night. HS were questioned about events during their residency, and FAC were questioned about events during the preceding three years. There was an 87% response rate for each group. HS slept 2.7 +/- 0.9 (SD) hours when on call vs 7.2 +/- 0.8 hours when not on call (p < 0.001). 44% of HS had fallen asleep when stopped at a light, vs 12.5% FAC (p < 0.001). 23% of HS had fallen asleep while driving vs. 8% FAC (ns). A total of 49% of HS had fallen asleep at the wheel; 90% of these events occurred post-call. In contrast, only 13% of FAC had fallen asleep at the wheel (p < 0.001). HS had received a total of 25 traffic citations for moving violations vs. 15 for FAC and were involved in 20 motor vehicle accidents vs. 11 for FAC. One traffic citation clearly resulted from HS falling asleep at the wheel vs. none for FAC. We conclude that HS frequently fall asleep when driving post-call. We speculate that current HS work schedules may place some HS at risk for injury to themselves and others. Further study, using prospectively objective measures is indicated.

  14. Integrated traction control strategy for distributed drive electric vehicles with improvement of economy and longitudinal driving stability

    OpenAIRE

    Zhang, Xudong; Göhlich, Dietmar

    2017-01-01

    This paper presents an integrated traction control strategy (ITCS) for distributed drive electric vehicles. The purpose of the proposed strategy is to improve vehicle economy and longitudinal driving stability. On high adhesion roads, economy optimization algorithm is applied to maximize motors efficiency by means of the optimized torque distribution. On low adhesion roads, a sliding mode control (SMC) algorithm is implemented to guarantee the wheel slip ratio around the optimal slip ratio po...

  15. Stay Awake Behind the Wheel (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    Being a safe driver requires complete focus on the road and the cars around you. Unfortunately, many people get behind the wheel when they’ve had a long day at work or haven’t gotten enough sleep. In this podcast, Dr. Anne Wheaton discusses the dangers of drowsy driving.

  16. Teens' distracted driving behavior: Prevalence and predictors.

    Science.gov (United States)

    Gershon, Pnina; Zhu, Chunming; Klauer, Sheila G; Dingus, Tom; Simons-Morton, Bruce

    2017-12-01

    Teen drivers' over-involvement in crashes has been attributed to a variety of factors, including distracted driving. With the rapid development of in-vehicle systems and portable electronic devices, the burden associated with distracted driving is expected to increase. The current study identifies predictors of secondary task engagement among teenage drivers and provides basis for interventions to reduce distracted driving behavior. We described the prevalence of secondary tasks by type and driving conditions and evaluated the associations between the prevalence of secondary task engagement, driving conditions, and selected psychosocial factors. The private vehicles of 83 newly-licensed teenage drivers were equipped with Data Acquisition Systems (DAS), which documented driving performance measures, including secondary task engagement and driving environment characteristics. Surveys administered at licensure provided psychosocial measures. Overall, teens engaged in a potentially distracting secondary task in 58% of sampled road clips. The most prevalent types of secondary tasks were interaction with a passenger, talking/singing (no passenger), external distraction, and texting/dialing the cell phone. Secondary task engagement was more prevalent among those with primary vehicle access and when driving alone. Social norms, friends' risky driving behaviors, and parental limitations were significantly associated with secondary task prevalence. In contrast, environmental attributes, including lighting and road surface conditions, were not associated with teens' engagement in secondary tasks. Our findings indicated that teens engaged in secondary tasks frequently and poorly regulate their driving behavior relative to environmental conditions. Practical applications: Peer and parent influences on secondary task engagement provide valuable objectives for countermeasures to reduce distracted driving among teenage drivers. Copyright © 2017 National Safety Council and

  17. Secondary drive of an internal combustion engine for an air presser. Nebenantrieb einer Brennkraftmaschine fuer einen Luftpresser

    Energy Technology Data Exchange (ETDEWEB)

    Kubis, H.

    1990-04-19

    The invention concerns an air presser propelled by a gearwheel and designed as a piston compressor. The drive gearwheel on the air presser crankshaft meshes with a gearwheel on the camshaft of the internal combustion engine. In the case of these drives, a negative torque of the air presser results when the top dead centre of the air presser piston is reached. This is accompanied by an unpleasant noise. In addition, the driving torque of the camshaft often has negative fractions. If the negative torque of the air presser is superposed by small or negative torques of the camshaft in the re-expansion phase additionally to the air presser wheel there will be a backward acceleration of the camshaft gear which propagates as impact into the rest of the gear drive. The invention prevents the backward acceleration of the camshaft wheel and minimizes stroke momentum and noise in the mesh of the camshaft wheel.

  18. A Four-Wheel-Rhombus-Arranged Mobility System for a New Lunar Robotic Rover

    Directory of Open Access Journals (Sweden)

    Guilin Wen

    2013-10-01

    Full Text Available Different from traditional ground vehicles, planetary robotic rovers with limited weight and power need to travel in unfamiliar and extremely arduous environments. In this paper, a newly developed four-wheel-rhombus-arranged (FWRA mobility system is presented as a lunar robotic rover with high mobility and a low-weight structure. The mobility system integrates independent active suspensions with a passive rotary link structure. The active suspension with swing arms improves the rover's capacity to escape from a trapped environment whereas the passive rotary link structure guarantees continuous contact between the four wheels and the terrain. The four-wheel-three-axis rhombus configuration of the mobility system gives a high degree of lightweight structure because it has a simple mechanism with the minimum number of wheels among wheeled rovers with three-axis off-road mobility. The performance evaluation of the lightweight nature of the structure, manoeuvrability and the mobility required in a planetary exploring environment are illustrated by theoretical analysis and partly shown by experiments on the developed rover prototype.

  19. A new energy-efficient control approach for space telescope drive system

    Science.gov (United States)

    Zhou, Wangping; Wang, Yong

    Drive control makes the telescope accurately track celestial bodies in spite of external and in-ternal disturbances, and is a key technique to the performance of telescopes. In this paper, we propose a nonlinear adaptive observer based on power reversible approach for high preci-sion position tracking, i.e., space telescopes. The nonlinear adaptive observer automatically estimates the disturbances in drive system, and the observed value is applied to compensate for the real disturbances. With greatly reduced disturbances, the control precision can be ev-idently improved. In conventional drive control, the brake device is often used to slow down the reaction wheel and may waste enormous energy. To avoid those disadvantages, an H-bridge is put forward for wheel speed regulation. Such H-bridge has four independent sections, and each section mainly consists of a power electronic switch and an anti-parallel diode. A pair of diagonal sections is switched on for speeding up the reaction wheel and the other pair act in reverse. During the period of the wheel slowing down, the armature current of drive motor goes through the two path-wise diodes to discharge the battery. Thusly, energy waste is avoided. Based on the disturbance compensation, an optimal controller is designed to minimize an eval-uation function which is made up of a weighted sum of position errors and energy consumption. The outputs of the controller are amplified to control the H-bridge. Simulations are performed in MATLAB language. The results show that high precision control can be obtained by the proposed approach. And the energy consumption will be remarkably reduced.

  20. Engagement Means Everyone

    Science.gov (United States)

    Patton, Carol

    2012-01-01

    Employee engagement is not just HR's responsibility. While HR is responsible for the process of measuring and driving engagement, improving it is actually everyone's responsibility. And that means reducing the barriers to productivity to drive business performance. Training departments can play a pivotal role. Their job is to enhance curriculum or…

  1. Characterizing Wheel-Soil Interaction Loads Using Meshfree Finite Element Methods: A Sensitivity Analysis for Design Trade Studies

    Science.gov (United States)

    Contreras, Michael T.; Trease, Brian P.; Bojanowski, Cezary; Kulakx, Ronald F.

    2013-01-01

    A wheel experiencing sinkage and slippage events poses a high risk to planetary rover missions as evidenced by the mobility challenges endured by the Mars Exploration Rover (MER) project. Current wheel design practice utilizes loads derived from a series of events in the life cycle of the rover which do not include (1) failure metrics related to wheel sinkage and slippage and (2) performance trade-offs based on grouser placement/orientation. Wheel designs are rigorously tested experimentally through a variety of drive scenarios and simulated soil environments; however, a robust simulation capability is still in development due to myriad of complex interaction phenomena that contribute to wheel sinkage and slippage conditions such as soil composition, large deformation soil behavior, wheel geometry, nonlinear contact forces, terrain irregularity, etc. For the purposes of modeling wheel sinkage and slippage at an engineering scale, meshfree nite element approaches enable simulations that capture su cient detail of wheel-soil interaction while remaining computationally feasible. This study implements the JPL wheel-soil benchmark problem in the commercial code environment utilizing the large deformation modeling capability of Smooth Particle Hydrodynamics (SPH) meshfree methods. The nominal, benchmark wheel-soil interaction model that produces numerically stable and physically realistic results is presented and simulations are shown for both wheel traverse and wheel sinkage cases. A sensitivity analysis developing the capability and framework for future ight applications is conducted to illustrate the importance of perturbations to critical material properties and parameters. Implementation of the proposed soil-wheel interaction simulation capability and associated sensitivity framework has the potential to reduce experimentation cost and improve the early stage wheel design proce

  2. Exponentially Biased Ground-State Sampling of Quantum Annealing Machines with Transverse-Field Driving Hamiltonians.

    Science.gov (United States)

    Mandrà, Salvatore; Zhu, Zheng; Katzgraber, Helmut G

    2017-02-17

    We study the performance of the D-Wave 2X quantum annealing machine on systems with well-controlled ground-state degeneracy. While obtaining the ground state of a spin-glass benchmark instance represents a difficult task, the gold standard for any optimization algorithm or machine is to sample all solutions that minimize the Hamiltonian with more or less equal probability. Our results show that while naive transverse-field quantum annealing on the D-Wave 2X device can find the ground-state energy of the problems, it is not well suited in identifying all degenerate ground-state configurations associated with a particular instance. Even worse, some states are exponentially suppressed, in agreement with previous studies on toy model problems [New J. Phys. 11, 073021 (2009)NJOPFM1367-263010.1088/1367-2630/11/7/073021]. These results suggest that more complex driving Hamiltonians are needed in future quantum annealing machines to ensure a fair sampling of the ground-state manifold.

  3. Estimating the Backup Reaction Wheel Orientation Using Reaction Wheel Spin Rates Flight Telemetry from a Spacecraft

    Science.gov (United States)

    Rizvi, Farheen

    2013-01-01

    A report describes a model that estimates the orientation of the backup reaction wheel using the reaction wheel spin rates telemetry from a spacecraft. Attitude control via the reaction wheel assembly (RWA) onboard a spacecraft uses three reaction wheels (one wheel per axis) and a backup to accommodate any wheel degradation throughout the course of the mission. The spacecraft dynamics prediction depends upon the correct knowledge of the reaction wheel orientations. Thus, it is vital to determine the actual orientation of the reaction wheels such that the correct spacecraft dynamics can be predicted. The conservation of angular momentum is used to estimate the orientation of the backup reaction wheel from the prime and backup reaction wheel spin rates data. The method is applied in estimating the orientation of the backup wheel onboard the Cassini spacecraft. The flight telemetry from the March 2011 prime and backup RWA swap activity on Cassini is used to obtain the best estimate for the backup reaction wheel orientation.

  4. Study on control schemes of flexible steering system of a multi-axle all-wheel-steering robot

    Directory of Open Access Journals (Sweden)

    Pingxia Zhang

    2016-05-01

    Full Text Available It is well known that a multi-axle wheeled robot possesses larger load capability and also higher drive performance. However, its steering flexibility is degraded due to the large number of wheels. In order to solve this problem, in this article, we proposed three control schemes based on the center of rotation or the steering angles of both the first- and last-axle wheels. To release these control schemes, steering mode selection and also the left wheel’s steering angle in a specific axle are added approaching a practical application. Thereafter, the remaining wheels’ steering angles can be calculated with the Ackerman steering theorem. In order to verify the control effects, a five-axle all-wheel-steering wheeled robot has been developed with the Bluetooth wireless monitor system. Based on the newly designed robot, validation experiments are carried out, such as lateral movement, situ rotation, and multi-mode steering within a narrow space. The results indicate that the proposed design in this article can ensure a more flexible and faster movement within a narrow space. It shows large potential in obstacle avoidance compared with the conventional partial-wheel steering mode.

  5. Innovative grinding wheel design for cost-effective machining of advanced ceramics. Phase I, final report

    Energy Technology Data Exchange (ETDEWEB)

    Licht, R.H.; Ramanath, S.; Simpson, M.; Lilley, E.

    1996-02-01

    Norton Company successfully completed the 16-month Phase I technical effort to define requirements, design, develop, and evaluate a next-generation grinding wheel for cost-effective cylindrical grinding of advanced ceramics. This program was a cooperative effort involving three Norton groups representing a superabrasive grinding wheel manufacturer, a diamond film manufacturing division and a ceramic research center. The program was divided into two technical tasks, Task 1, Analysis of Required Grinding Wheel Characteristics, and Task 2, Design and Prototype Development. In Task 1 we performed a parallel path approach with Superabrasive metal-bond development and the higher technical risk, CVD diamond wheel development. For the Superabrasive approach, Task 1 included bond wear and strength tests to engineer bond-wear characteristics. This task culminated in a small-wheel screening test plunge grinding sialon disks. In Task 2, an improved Superabrasive metal-bond specification for low-cost machining of ceramics in external cylindrical grinding mode was identified. The experimental wheel successfully ground three types of advanced ceramics without the need for wheel dressing. The spindle power consumed by this wheel during test grinding of NC-520 sialon is as much as to 30% lower compared to a standard resin bonded wheel with 100 diamond concentration. The wheel wear with this improved metal bond was an order of magnitude lower than the resin-bonded wheel, which would significantly reduce ceramic grinding costs through fewer wheel changes for retruing and replacements. Evaluation of ceramic specimens from both Tasks 1 and 2 tests for all three ceramic materials did not show evidence of unusual grinding damage. The novel CVD-diamond-wheel approach was incorporated in this program as part of Task 1. The important factors affecting the grinding performance of diamond wheels made by CVD coating preforms were determined.

  6. Driver`s behavior and the motion of motorized wheelchair when driving over rough surfaces; Dansa nado fuseichi sokoji no dendo kurumaisu no undo to join no kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, A; Yokomori, M; Yamaguchi, S [Meijo University, Aichi (Japan)

    1997-10-01

    We analyzed about the motion of motorized wheelchairs and the driver`s behavior when passing over the small obstacles in place of the rough surface road or the gateway of house and road by experiment. The tested two type wheelchairs are the front wheel drive and the rear wheel drive. The lean angle of head and the pulse rate of driver, the feeling for stability and the yaw angle and the roll angle of the wheelchair bodies, and the deflection angle of front wheels of rear drive. 4 refs., 11 figs., 1 tab.

  7. Teen Drinking and Driving – What You Need to Know PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2012-10-02

    This 60 second public service announcement is based on the October 2012 CDC Vital Signs report. It’s illegal and dangerous for teens to drink any alcohol and then drive. Still, one in ten high school teens drank and got behind the wheel in 2011. A parent-teen driving agreement is a good way for parents to help keep young drivers safe behind the wheel.  Created: 10/2/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 10/2/2012.

  8. The response of a high-speed train wheel to a harmonic wheel-rail force

    International Nuclear Information System (INIS)

    Sheng, Xiaozhen; Liu, Yuxia; Zhou, Xin

    2016-01-01

    The maximum speed of China's high-speed trains currently is 300km/h and expected to increase to 350-400km/h. As a wheel travels along the rail at such a high speed, it is subject to a force rotating at the same speed along its periphery. This fast moving force contains not only the axle load component, but also many components of high frequencies generated from wheel-rail interactions. Rotation of the wheel also introduces centrifugal and gyroscopic effects. How the wheel responds is fundamental to many issues, including wheel-rail contact, traction, wear and noise. In this paper, by making use of its axial symmetry, a special finite element scheme is developed for responses of a train wheel subject to a vertical and harmonic wheel-rail force. This FE scheme only requires a 2D mesh over a cross-section containing the wheel axis but includes all the effects induced by wheel rotation. Nodal displacements, as a periodic function of the cross-section angle 6, can be decomposed, using Fourier series, into a number of components at different circumferential orders. The derived FE equation is solved for each circumferential order. The sum of responses at all circumferential orders gives the actual response of the wheel. (paper)

  9. Opportunity's View After Drive on Sol 1806 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11816 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11816 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, full-circle view of the rover's surroundings just after driving 60.86 meters (200 feet) on the 1,806th Martian day, or sol, of Opportunity's surface mission (Feb. 21, 2009). North is at the center; south at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Engineers designed the Sol 1806 drive to be driven backwards as a strategy to redistribute lubricant in the rovers wheels. The right-front wheel had been showing signs of increased friction. The rover's position after the Sol 1806 drive was about 2 kilometer (1.2 miles) south southwest of Victoria Crater. Cumulative odometry was 14.74 kilometers (9.16 miles) since landing in January 2004, including 2.96 kilometers (1.84 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a cylindrical-perspective projection with geometric seam correction.

  10. Simulation of Dynamic Behavior of the Flexible Wheel of the Double Harmonic Gear Transmission

    Directory of Open Access Journals (Sweden)

    Draghiţa Ianici

    2014-06-01

    Full Text Available The paper presents the construction and functioning of a new type the harmonic gear transmission named double harmonic gear transmission, which can be used in the construction drives of industrial robots. In the second part of this paper is presented the dynamic analysis of the double harmonic gear transmission, which is based on the results of the numerical simulations of the flexible wheel in case of its deformation with a mechanical wave generator with disc cam. Investigation of dynamic behavior of the flexible toothed wheel was performed by using the finite element method in SolidWorks Simulation software.

  11. Motion Control of Four-Wheel Independently Actuated Electric Ground Vehicles considering Tire Force Saturations

    Directory of Open Access Journals (Sweden)

    Rongrong Wang

    2013-01-01

    Full Text Available A vehicle stability control approach for four-wheel independently actuated (FWIA electric vehicles is presented. The proposed control method consists of a higher-level controller and a lower-level controller. An adaptive control-based higher-level controller is designed to yield the vehicle virtual control efforts to track the desired vehicle motions due to the possible modeling inaccuracies and parametric uncertainties. The lower-level controller considering tire force saturation is given to allocate the required control efforts to the four in-wheel motors for providing the desired tire forces. An analytic method is given to distribute the high-level control efforts, without using the numerical-optimization-based control allocation algorithms. Simulations based on a high-fidelity, CarSim, and full-vehicle model show the effectiveness of the control approach.

  12. Development of a control model for a four wheel mecanum vehicle

    CSIR Research Space (South Africa)

    De Villiers, M

    2012-01-01

    Full Text Available in this paper accounts for the fact that the contact point in fact changes position down the axle of the wheel as the angle roller moves on the ground. The developed control model is verified with experimental results. Using the refined model, control of Mecanum...

  13. Non-Model-Based Control of a Wheeled Vehicle Pulling Two Trailers to Provide Early Powered Mobility and Driving Experiences.

    Science.gov (United States)

    Sanders Td Vr, David A

    2018-01-01

    Non-model-based control of a wheeled vehicle pulling two trailers is proposed. It is a fun train for disabled children consisting of a locomotive and two carriages. The fun train has afforded opportunities for both disabled and able bodied young people to share an activity and has provided early driving experiences for disabled children; it has introduced them to assistive and powered mobility. The train is a nonlinear system and subject to nonholonomic kinematic constraints, so that position and state depend on the path taken to get there. The train is described, and then, a robust control algorithm using proportional-derivative filtered errors is proposed to control the locomotive. The controller was not dependent on an accurate model of the train, because the mass of the vehicle and two carriages changed depending on the number, size, and shape of children and wheelchair seats on the train. The controller was robust and stable in uncertainty. Results are presented to show the effectiveness of the approach, and the suggested control algorithm is shown to be acceptable without knowing the exact plant dynamics.

  14. A tyre slip-based integrated chassis control of front/rear traction distribution and four-wheel independent brake from moderate driving to limit handling

    Science.gov (United States)

    Joa, Eunhyek; Park, Kwanwoo; Koh, Youngil; Yi, Kyongsu; Kim, Kilsoo

    2018-04-01

    This paper presents a tyre slip-based integrated chassis control of front/rear traction distribution and four-wheel braking for enhanced performance from moderate driving to limit handling. The proposed algorithm adopted hierarchical structure: supervisor - desired motion tracking controller - optimisation-based control allocation. In the supervisor, by considering transient cornering characteristics, desired vehicle motion is calculated. In the desired motion tracking controller, in order to track desired vehicle motion, virtual control input is determined in the manner of sliding mode control. In the control allocation, virtual control input is allocated to minimise cost function. The cost function consists of two major parts. First part is a slip-based tyre friction utilisation quantification, which does not need a tyre force estimation. Second part is an allocation guideline, which guides optimally allocated inputs to predefined solution. The proposed algorithm has been investigated via simulation from moderate driving to limit handling scenario. Compared to Base and direct yaw moment control system, the proposed algorithm can effectively reduce tyre dissipation energy in the moderate driving situation. Moreover, the proposed algorithm enhances limit handling performance compared to Base and direct yaw moment control system. In addition to comparison with Base and direct yaw moment control, comparison the proposed algorithm with the control algorithm based on the known tyre force information has been conducted. The results show that the performance of the proposed algorithm is similar with that of the control algorithm with the known tyre force information.

  15. Apparatus for feeding nuclear fuel pellets to a loading tray

    International Nuclear Information System (INIS)

    Huggins, T.B.

    1979-01-01

    Apparatus for feeding nuclear fuel pellets at a uniform predetermined rate between pellet centering and grinding apparatus and a tray for loading pellets into nuclear fuel rod. Pellets discharged from the grinding apparatus are conveyed by a belt to a drive wheel forcing the pellets in engagement with the belt. The pellets under the drive wheel are capable of pushing a line of about 36 pellets onto a pellet dumping mechanism. As the dumping mechanism is actuated to dump the pellets on to a loading tray, the pellets moving toward the mechanism are stopped and the drive wheel is simultaneously lifted off the pellets until the pellet dumping process is completed. (U.K.)

  16. Design of Wheeled Mobile Robot with Tri-Star Wheel as Rescue Robot

    Directory of Open Access Journals (Sweden)

    Rafiuddin Syam

    2014-10-01

    Full Text Available This study aims to design, and analyze a mobile robot that can handle some of the obstacles, they are uneven surfaces, slopes, can also climb stairs. WMR in this study is Tristar wheel that is containing three wheels for each set. On average surface only two wheels in contact with the surface, if there is an uneven surface or obstacle then the third wheel will rotate with the rotation center of the wheel in contact with the leading obstacle then only one wheel in contact with the surface. This study uses the C language program. Furthermore, the minimum thrust to be generated torque of the motor and transmission is 9.56 kg. The results obtained by calculation and analysis of DC motors used must have a torque greater than 14.67 kg.cm. Minimum thrust to be generated motor torque and the transmission is 9.56 kg. The experimental results give good results for robot to moving forward, backward, turn left, turn right and climbing the stairs.

  17. High frequency vibration characteristics of electric wheel system under in-wheel motor torque ripple

    Science.gov (United States)

    Mao, Yu; Zuo, Shuguang; Wu, Xudong; Duan, Xianglei

    2017-07-01

    With the introduction of in-wheel motor, the electric wheel system encounters new vibration problems brought by motor torque ripple excitation. In order to analyze new vibration characteristics of electric wheel system, torque ripple of in-wheel motor based on motor module and vector control system is primarily analyzed, and frequency/order features of the torque ripple are discussed. Then quarter vehicle-electric wheel system (QV-EWS) dynamics model based on the rigid ring tire assumption is established and the main parameters of the model are identified according to tire free modal test. Modal characteristics of the model are further analyzed. The analysis indicates that torque excitation of in-wheel motor is prone to arouse horizontal vibration, in which in-phase rotational, anti-phase rotational and horizontal translational modes of electric wheel system mainly participate. Based on the model, vibration responses of the QV-EWS under torque ripple are simulated. The results show that unlike vertical low frequency (lower than 20 Hz) vibration excited by road roughness, broadband torque ripple will arouse horizontal high frequency (50-100 Hz) vibration of electric wheel system due to participation of the three aforementioned modes. To verify the theoretical analysis, the bench experiment of electric wheel system is conducted and vibration responses are acquired. The experiment demonstrates the high frequency vibration phenomenon of electric wheel system and the measured order features as well as main resonant frequencies agree with simulation results. Through theoretical modeling, analysis and experiments this paper reveals and explains the high frequency vibration characteristics of electric wheel system, providing references for the dynamic analysis, optimal design of QV-EWS.

  18. Asleep at the automated wheel-Sleepiness and fatigue during highly automated driving.

    Science.gov (United States)

    Vogelpohl, Tobias; Kühn, Matthias; Hummel, Thomas; Vollrath, Mark

    2018-03-20

    Due to the lack of active involvement in the driving situation and due to monotonous driving environments drivers with automation may be prone to become fatigued faster than manual drivers (e.g. Schömig et al., 2015). However, little is known about the progression of fatigue during automated driving and its effects on the ability to take back manual control after a take-over request. In this driving simulator study with Nö=ö60 drivers we used a three factorial 2ö×ö2ö×ö12 mixed design to analyze the progression (12ö×ö5ömin; within subjects) of driver fatigue in drivers with automation compared to manual drivers (between subjects). Driver fatigue was induced as either mainly sleep related or mainly task related fatigue (between subjects). Additionally, we investigated the drivers' reactions to a take-over request in a critical driving scenario to gain insights into the ability of fatigued drivers to regain manual control and situation awareness after automated driving. Drivers in the automated driving condition exhibited facial indicators of fatigue after 15 to 35ömin of driving. Manual drivers only showed similar indicators of fatigue if they suffered from a lack of sleep and then only after a longer period of driving (approx. 40ömin). Several drivers in the automated condition closed their eyes for extended periods of time. In the driving with automation condition mean automation deactivation times after a take-over request were slower for a certain percentage (about 30%) of the drivers with a lack of sleep (Mö=ö3.2; SDö=ö2.1ös) compared to the reaction times after a long drive (Mö=ö2.4; SDö=ö0.9ös). Drivers with automation also took longer than manual drivers to first glance at the speed display after a take-over request and were more likely to stay behind a braking lead vehicle instead of overtaking it. Drivers are unable to stay alert during extended periods of automated driving without non-driving related tasks. Fatigued drivers could

  19. Driving simulator sickness: Impact on driving performance, influence of blood alcohol concentration, and effect of repeated simulator exposures.

    Science.gov (United States)

    Helland, Arne; Lydersen, Stian; Lervåg, Lone-Eirin; Jenssen, Gunnar D; Mørland, Jørg; Slørdal, Lars

    2016-09-01

    Simulator sickness is a major obstacle to the use of driving simulators for research, training and driver assessment purposes. The purpose of the present study was to investigate the possible influence of simulator sickness on driving performance measures such as standard deviation of lateral position (SDLP), and the effect of alcohol or repeated simulator exposure on the degree of simulator sickness. Twenty healthy male volunteers underwent three simulated driving trials of 1h's duration with a curvy rural road scenario, and rated their degree of simulator sickness after each trial. Subjects drove sober and with blood alcohol concentrations (BAC) of approx. 0.5g/L and 0.9g/L in a randomized order. Simulator sickness score (SSS) did not influence the primary outcome measure SDLP. Higher SSS significantly predicted lower average speed and frequency of steering wheel reversals. These effects seemed to be mitigated by alcohol. Higher BAC significantly predicted lower SSS, suggesting that alcohol inebriation alleviates simulator sickness. The negative relation between the number of previous exposures to the simulator and SSS was not statistically significant, but is consistent with habituation to the sickness-inducing effects, as shown in other studies. Overall, the results suggest no influence of simulator sickness on SDLP or several other driving performance measures. However, simulator sickness seems to cause test subjects to drive more carefully, with lower average speed and fewer steering wheel reversals, hampering the interpretation of these outcomes as measures of driving impairment and safety. BAC and repeated simulator exposures may act as confounding variables by influencing the degree of simulator sickness in experimental studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. An Omnidirectional Mobile Millimeters Size Micro-Robot with Novel Duel-Wheels

    Directory of Open Access Journals (Sweden)

    Zhenbo Li

    2006-09-01

    Full Text Available A millimeters size omni-directional mobile micro-robot is presented in this paper. A unique duel-wheel structure is designed for no-slip motion during the steering, by turning the slip friction between the wheel and ground into rolling friction. The robot was driven by four electromagnetic micromotors with 2.1mm×2.1mm×1.3mm size. Three of them are for translation and the other one is for rotation. Kinematics model is analyzed to prove the omni-directional mobility. Virtual-Winding Approach (VWA and PWM-Based Vector-Synthesize Approach(PBVSA current control methods are presented to satisfy a requirement of higher positioning accuracy. Experimental results demonstrate the feasibility of this concept.

  1. An Omnidirectional Mobile Millimeters Size Micro-Robot with Novel Duel-Wheels

    Directory of Open Access Journals (Sweden)

    Chen Zhang

    2008-11-01

    Full Text Available A millimeters size omni-directional mobile micro-robot is presented in this paper. A unique duel-wheel structure is designed for no-slip motion during the steering, by turning the slip friction between the wheel and ground into rolling friction. The robot was driven by four electromagnetic micromotors with 2.1mm?2.1mm?1.3mm size. Three of them are for translation and the other one is for rotation. Kinematics model is analyzed to prove the omni-directional mobility. Virtual-Winding Approach (VWA and PWM-Based VectorSynthesize Approach(PBVSA current control methods are presented to satisfy a requirement of higher positioning accuracy. Experimental results demonstrate the feasibility of this concept.

  2. A dynamic wheel-rail impact analysis of railway track under wheel flat by finite element analysis

    Science.gov (United States)

    Bian, Jian; Gu, Yuantong; Murray, Martin Howard

    2013-06-01

    Wheel-rail interaction is one of the most important research topics in railway engineering. It involves track impact response, track vibration and track safety. Track structure failures caused by wheel-rail impact forces can lead to significant economic loss for track owners through damage to rails and to the sleepers beneath. Wheel-rail impact forces occur because of imperfections in the wheels or rails such as wheel flats, irregular wheel profiles, rail corrugations and differences in the heights of rails connected at a welded joint. A wheel flat can cause a large dynamic impact force as well as a forced vibration with a high frequency, which can cause damage to the track structure. In the present work, a three-dimensional finite element (FE) model for the impact analysis induced by the wheel flat is developed by the use of the FE analysis (FEA) software package ANSYS and validated by another validated simulation. The effect of wheel flats on impact forces is thoroughly investigated. It is found that the presence of a wheel flat will significantly increase the dynamic impact force on both rail and sleeper. The impact force will monotonically increase with the size of wheel flats. The relationships between the impact force and the wheel flat size are explored from this FEA and they are important for track engineers to improve their understanding of the design and maintenance of the track system.

  3. A traction control strategy with an efficiency model in a distributed driving electric vehicle.

    Science.gov (United States)

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention.

  4. A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

    Science.gov (United States)

    Lin, Cheng

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

  5. Soil mechanical stresses in high wheel load agricultural field traffic: a case study

    DEFF Research Database (Denmark)

    Lamandé, Mathieu; Schjønning, Per

    2017-01-01

    highly skewed. Across tyres, the maximum stress in the contact area correlated linearly with, but was much higher than, the mean ground pressure. For each of the three soil depths, the maximum stresses under the tyres were significantly correlated with the wheel load, but not with other loading......Subsoil compaction is a serious long-term threat to soil functions. Only a few studies have quantified the mechanical stresses reaching deep subsoil layers for modern high wheel load machinery. In the present study we measured the vertical stresses in the tyre–soil contact area and at 0.3, 0...

  6. Reinventing the wheel: comparison of two wheel cage styles for assessing mouse voluntary running activity.

    Science.gov (United States)

    Seward, T; Harfmann, B D; Esser, K A; Schroder, E A

    2018-04-01

    Voluntary wheel cage assessment of mouse activity is commonly employed in exercise and behavioral research. Currently, no standardization for wheel cages exists resulting in an inability to compare results among data from different laboratories. The purpose of this study was to determine whether the distance run or average speed data differ depending on the use of two commonly used commercially available wheel cage systems. Two different wheel cages with structurally similar but functionally different wheels (electromechanical switch vs. magnetic switch) were compared side-by-side to measure wheel running data differences. Other variables, including enrichment and cage location, were also tested to assess potential impacts on the running wheel data. We found that cages with the electromechanical switch had greater inherent wheel resistance and consistently led to greater running distance per day and higher average running speed. Mice rapidly, within 1-2 days, adapted their running behavior to the type of experimental switch used, suggesting these running differences are more behavioral than due to intrinsic musculoskeletal, cardiovascular, or metabolic limits. The presence of enrichment or location of the cage had no detectable impact on voluntary wheel running. These results demonstrate that mice run differing amounts depending on the type of cage and switch mechanism used and thus investigators need to report wheel cage type/wheel resistance and use caution when interpreting distance/speed run across studies. NEW & NOTEWORTHY The results of this study highlight that mice will run different distances per day and average speed based on the inherent resistance present in the switch mechanism used to record data. Rapid changes in running behavior for the same mouse in the different cages demonstrate that a strong behavioral factor contributes to classic exercise outcomes in mice. Caution needs to be taken when interpreting mouse voluntary wheel running activity to

  7. METHOD OF THE DRIVE POWER DETERMINATION OF THE MECHANISMS OF THE BRIDGE CRANE MOVEMENT CONSIDERING THE ROLLING FRICTION

    Directory of Open Access Journals (Sweden)

    V. M. Bohomaz

    2015-08-01

    Full Text Available Purpose. The value of drive resistance to its movement is the main parameter at calculating the drive power of bridge crane. The value of the wheel rolling friction on the rails is one of the important parts of the resistance to movement. It is necessary to determine the dependence of static (dynamic quantities of resistance to the bridge crane movement on a straight section of the track from the position of the bogie in the span, and explore the influence of the wheel flanges resistance for wear. Methodology. Using the analytical dependences for determining the rolling friction coefficient, that depends on the size of the half-width of the contact between the wheel and rail, the improved method for calculating the required drive power of the crane was proposed. Findings. With the proposed method of power calculation the characteristic curve of the crane wheel loads, the coefficient of rolling friction of the wheels and the crane resistance to movement from the position of the bogie on span were built. In the result of graphs analysis it was found that the engine power, obtained by the proposed method is higher than the recommended by the existing standards. The more precise formula for determining the total coefficient of sliding friction that takes into account the friction of wheel flanges on the rail is given. The characteristic curves of such coefficient of friction and the total resistance to movement of the position of the crane bogie were built. Originality. The scientists proposed an improved method of determining the required engine power of bridge crane, which takes into account the effect of rolling friction of the wheels on the rails and the bogie in the span. The improved formula for determining the coefficient of friction that takes into account the friction wheel flanges of the rail was given. The characteristic curve of this coefficient of friction and the total resistance movement of crane from the position of the crane bogie

  8. The Influence of Wheel/Rail Contact Conditions on the Microstructure and Hardness of Railway Wheels

    Directory of Open Access Journals (Sweden)

    Paul Molyneux-Berry

    2014-01-01

    Full Text Available The susceptibility of railway wheels to wear and rolling contact fatigue damage is influenced by the properties of the wheel material. These are influenced by the steel composition, wheel manufacturing process, and thermal and mechanical loading during operation. The in-service properties therefore vary with depth below the surface and with position across the wheel tread. This paper discusses the stress history at the wheel/rail contact (derived from dynamic simulations and observed variations in hardness and microstructure. It is shown that the hardness of an “in-service” wheel rim varies significantly, with three distinct effects. The underlying hardness trend with depth can be related to microstructural changes during manufacturing (proeutectoid ferrite fraction and pearlite lamellae spacing. The near-surface layer exhibits plastic flow and microstructural shear, especially in regions which experience high tangential forces when curving, with consequentially higher hardness values. Between 1 mm and 7 mm depth, the wheel/rail contacts cause stresses exceeding the material yield stress, leading to work hardening, without a macroscopic change in microstructure. These changes in material properties through the depth of the wheel rim would tend to increase the likelihood of crack initiation on wheels toward the end of their life. This correlates with observations from several train fleets.

  9. 49 CFR 570.10 - Wheel assemblies.

    Science.gov (United States)

    2010-10-01

    ... bead through one full wheel revolution and note runout in excess of one-eighth of an inch. (c) Mounting... 49 Transportation 6 2010-10-01 2010-10-01 false Wheel assemblies. 570.10 Section 570.10... Pounds or Less § 570.10 Wheel assemblies. (a) Wheel integrity. A tire rim, wheel disc, or spider shall...

  10. Effect of vertical ground motion on earthquake-induced derailment of railway vehicles over simply-supported bridges

    Science.gov (United States)

    Jin, Zhibin; Pei, Shiling; Li, Xiaozhen; Liu, Hongyan; Qiang, Shizhong

    2016-11-01

    The running safety of railway vehicles on bridges can be negatively affected by earthquake events. This phenomenon has traditionally been investigated with only the lateral ground excitation component considered. This paper presented results from a numerical investigation on the contribution of vertical ground motion component to the derailment of vehicles on simply-supported bridges. A full nonlinear wheel-rail contact model was used in the investigation together with the Hertzian contact theory and nonlinear creepage theory, which allows the wheel to jump vertically and separate from the rail. The wheel-rail relative displacement was used as the criterion for derailment events. A total of 18 ground motion records were used in the analysis to account for the uncertainty of ground motions. The results showed that inclusion of vertical ground motion will likely increase the chance of derailment. It is recommended to include vertical ground motion component in earthquake induced derailment analysis to ensure conservative estimations. The derailment event on bridges was found to be more closely related to the deck acceleration rather than the ground acceleration.

  11. Stay Awake Behind the Wheel (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2016-11-10

    Being a safe driver requires complete focus on the road and the cars around you. Unfortunately, many people get behind the wheel when they’ve had a long day at work or haven’t gotten enough sleep. In this podcast, Dr. Anne Wheaton discusses the dangers of drowsy driving.  Created: 11/10/2016 by MMWR.   Date Released: 11/10/2016.

  12. Design of Wheeled Mobile Robot with Tri-Star Wheel as Rescue Robot

    Directory of Open Access Journals (Sweden)

    Rafiuddin Syam

    2016-05-01

    Full Text Available This study aims to design, and analyze a mobilerobot that can handle some of the obstacles, they are unevensurfaces, slopes, can also climb stairs. WMR in this study is Tristarwheel that is containing three wheels for each set. Onaverage surface only two wheels in contact with the surface, ifthere is an uneven surface or obstacle then the third wheel willrotate with the rotation center of the wheel in contact with theleading obstacle then only one wheel in contact with the surface.This study uses the C language program. Furthermore, theminimum thrust to be generated torque of the motor andtransmission is 9.56 kg. The results obtained by calculation andanalysis of DC motors used must have a torque greater than14.67 kg.cm. Minimum thrust to be generated motor torque andthe transmission is 9.56 kg. The experimental results give goodresults for robot to moving forward, backward, turn left, turnright and climbing the stairs

  13. Using unconstrained tongue motion as an alternative control mechanism for wheeled mobility.

    Science.gov (United States)

    Huo, Xueliang; Ghovanloo, Maysam

    2009-06-01

    Tongue drive system (TDS) is a tongue-operated, minimally invasive, unobtrusive, noncontact, and wireless assistive technology that infers users' intentions by detecting and classifying their voluntary tongue motions, and translating them to user-defined commands. We have developed customized interface circuitry between an external TDS (eTDS) prototype and a commercial powered wheelchair (PWC) as well as three control strategies to evaluate the tongue motion as an alternative control input for wheeled mobility. We tested the eTDS performance in driving PWCs on 12 able-bodied human subjects, of which 11 were novice. The results showed that all subjects could complete navigation tasks by operating the PWC using their tongue motions. Despite little prior experience, the average time using the eTDS and the tongue was only approximately three times longer than using a joystick and the fingers. Navigation time was strongly dependant on the number of issued commands, which reduced by gaining experience. Particularly, the unintended issued commands (the Midas touch problem) were rare, demonstrating the effectiveness of the tongue tracking and external magnetic field cancellation algorithms as well as the safety of the TDS for wheeled mobility.

  14. Simulation modeling of wheeled vehicle dynamics on the stand "Roller"

    Directory of Open Access Journals (Sweden)

    G. O. Kotiev

    2014-01-01

    Full Text Available The tests are an integral part of the wheeled vehicle design, manufacturing, and operation. The need for their conducting arises from the research and experimental activities to assess the qualitative and quantitative characteristics of the vehicles in general, as well as the individual components and assemblies. It is obvious that a variety of design features of wheeled vehicles request a development of methods both for experimental studies and for creating the original bench equipment for these purposes.The main positive feature of bench tests of automotive engineering is a broad capability to control the combinations of traction loads, speed rates, and external input conditions. Here, the steady state conditions can be used for a long time, allowing all the necessary measurements to be made, including those with video and photo recording experiment.It is known that the benefits of test "M" type (using a roller dynamometer include a wide range of test modes, which do not depend on the climatic conditions, as well as a capability to use a computer-aided testing programs. At the same time, it is known that the main drawback of bench tests of full-size vehicle is that the tire rolling conditions on the drum mismatch to the real road pavements, which are difficult to simulate on the drum surface. This problem can be solved owing to wheeled vehicle tests at the benches "Roller" to be, in efficiency, the most preferable research method. The article gives a detailed presentation of developed at BMSTU approach to its solving.Problem of simulation mathematical modeling has been solved for the vehicle with the wheel formula 8 × 8, and individual wheel-drive.The simulation results have led to the conclusion that the proposed principle to simulate a vehicle rolling on a smooth non-deformable support base using a bench " Roller " by simulation modeling is efficient.

  15. Steering redundancy for self-driving vehicles using differential braking

    Science.gov (United States)

    Jonasson, M.; Thor, M.

    2018-05-01

    This paper describes how differential braking can be used to turn a vehicle in the context of providing fail-operational control for self-driving vehicles. Two vehicle models are developed with differential input. The models are used to explain the bounds of curvature that differential braking provides and they are then validated with measurements in a test vehicle. Particular focus is paid on wheel suspension effects that significantly influence the obtained curvature. The vehicle behaviour and its limitations due to wheel suspension effects are, owing to the vehicle models, defined and explained. Finally, a model-based controller is developed to control the vehicle curvature during a fault by differential braking. The controller is designed to compensate for wheel angle disturbance that is likely to occur during the control event.

  16. Validation of the finite element simulation to estimate the rolling resistance of a non-driving wheel with experimental tests

    Directory of Open Access Journals (Sweden)

    N Dibagar

    2015-09-01

    Full Text Available Introduction: Encountering soil from the viewpoint of management and product manufacturing has always been considered important, and an attempt is always made hat the tools and contrasting methods of soil be designed in such a way that itself prevents, as much as possible, the destructive consequences or energy waste that include economical or environmental limitations. Enhancing the soil encountering methods, quality reformation, and its related equipment, requires performing reliable tests in actual soil conditions. Considering the complexity and variety of variables in soil and machine contrast, this is a hard task. Hence, the numeral simulations are the key of all optimizations that illustrate efficient models by removing the costly farm tests and reducing research time. Tire is one of the main factors engaged with soil, and it is one of those tools that are discussable in both farms, and software environments. Despite the complexities in soil behavior, and tire geometry, modeling, tire movement on the soil has been the researchers’ objective from the past. Materials and methods: A non-linear finite element (FE model of the interaction of a non-driving tire with soil surface was developed to investigate the influence of the forward speed, tire inflation pressure and vertical load on rolling resistance using ABAQUS/Explicit code. In this research numerical and experimental tests were done under different conditions in order to estimate tire rolling resistance. In numerical tests, the soil part was simulated as a one-layer viscous-elastic material with a Drucker-Prager model by considering realistic soil properties. These properties included elastic and plastic properties which were obtained in the soil laboratory using relevant tests. The soil samples were prepared from the soil which was inside the soil bin. The same soil was utilized in experimental tests. Finite strain hyper elasticity model is developed to model nearly incompressible

  17. Defining Toll Fee of Wheeling Renewable with Reference to a Gas Pipeline in Indonesia

    Science.gov (United States)

    Hakim, Amrullah

    2017-07-01

    Indonesia has a huge number of renewable energy sources (RE) however; the utilization of these is currently very low. The main challenge of power production is its alignment with consumption levels; supply should equal demand at all times. There is a strong initiative from corporations with high energy demand, compared to other sectors, to apply a renewable portfolio standard for their energy input, e.g. 15% of their energy consumption requirement must come from a renewable energy source. To support this initiative, the utilization of power wheeling will help large factories on industrial estates to source firm and steady renewables from remote sites. The wheeling renewable via PLN’s transmission line has been regulated under the Ministry Decree in 2015 however; the tariff or toll fee has not yet been defined. The potential project to apply wheeling renewable will obtain power supply from a geothermal power plant, with power demand from the scattered factories under one company. This is the concept driving the application of power wheeling in the effort to push the growth of renewable energy in Indonesia. Given that the capacity of PLN’s transmission line are normally large and less congested compared to distribution line, the wheeling renewable can accommodate the scattered factories locations which then results in the cheaper toll fee of the wheeling renewable. Defining the best toll fee is the main topic of this paper with comparison of the toll fee of the gas pipeline infrastructure in Indonesia, so that it can be applied massively to achieve COP21’s commitment.

  18. Inertia Wheel on Low-Noise Active Magnetic Suspension

    Science.gov (United States)

    Carabelli, S.; Genta, G.; Silvagni, M.; Tonoli, A.

    2002-01-01

    the inertia wheel, particularly for what the disturbances caused by the rotor on the supporting structure are concerned, in actual microgravity conditions and to validate different control strategies. At present the engineering model is completed for what the mechanical subsystems and the electromechanical parts of the bearings are concerned. The drive motor is at an advanced design stage and the control electronics is almost completed. The construction phase will be completed within four to six months. A number of ground tests aimed to verifying that the device is able to operate satisfactorily are planned to be completed within the end of year 2002.

  19. Tracked Vehicle Road Wheel Puller

    Science.gov (United States)

    2009-02-01

    employed for removing smaller-size components, such as bolts and the like. U.S. Patent No. 5,410,792, issued to Freeman (3), discloses a caster wheel ...separation of the rubberized annular layer from the outer annular surface of the wheel . Figure 5 further illustrates a modification of the wheel puller...2001. 2. Rubino et al. Pulling Tool. U.S. Patent 5,479,688, 1996. 3. Freeman. Caster Wheel Axle Extraction Apparatus. U.S. Patent 5,410,792

  20. Cryogenic actuator testing for the SAFARI ground calibration setup

    Science.gov (United States)

    de Jonge, C.; Eggens, M.; Nieuwenhuizen, A. C. T.; Detrain, A.; Smit, H.; Dieleman, P.

    2012-09-01

    For the on-ground calibration setup of the SAFARI instrument cryogenic mechanisms are being developed at SRON Netherlands Institute for Space Research, including a filter wheel, XYZ-scanner and a flipmirror mechanism. Due to the extremely low background radiation requirement of the SAFARI instrument, all of these mechanisms will have to perform their work at 4.5 Kelvin and low-dissipative cryogenic actuators are required to drive these mechanisms. In this paper, the performance of stepper motors, piezoelectric actuators and brushless DC-motors as cryogenic actuators are compared. We tested stepper motor mechanical performance and electrical dissipation at 4K. The actuator requirements, test setup and test results are presented. Furthermore, design considerations and early performance tests of the flipmirror mechanism are discussed. This flipmirror features a 102 x 72 mm aluminum mirror that can be rotated 45°. A Phytron stepper motor with reduction gearbox has been chosen to drive the flipmirror. Testing showed that this motor has a dissipation of 49mW at 4K with a torque of 60Nmm at 100rpm. Thermal modeling of the flipmirror mechanism predicts that with proper thermal strapping the peak temperature of the flipmirror after a single action will be within the background level requirements of the SAFARI instrument. Early tests confirm this result. For low-duty cycle operations commercial stepper motors appear suitable as actuators for test equipment in the SAFARI on ground calibration setup.

  1. Association between reported sleep need and sleepiness at the wheel: comparative study on French highways between 1996 and 2011.

    Science.gov (United States)

    Quera-Salva, M A; Hartley, S; Sauvagnac-Quera, R; Sagaspe, P; Taillard, J; Contrand, B; Micoulaud, J A; Lagarde, E; Barbot, F; Philip, P

    2016-12-21

    To investigate the evolution over 15 years of sleep schedules, sleepiness at the wheel and driving risk among highway drivers. Comparative survey including questions on usual sleep schedules and before the trip, sleepiness at the wheel, the Epworth sleepiness scale, Basic Nordic Sleep Questionnaire (BNSQ) and a travel questionnaire. 80% of drivers stopped by the highway patrol agreed to participate in both studies with a total of 3545 drivers in 2011 and 2196 drivers in 1996 interviewed. After standardisation based on sex, age and mean annual driving distance, drivers in 2011 reported shorter sleep time on week days (psleep time (p15 indicating severe sleepiness. Even if drivers in 2011 reported good sleep hygiene prior to a highway journey, drivers have reduced their mean weekly sleep duration over 15 years and have a higher risk of sleepiness at the wheel. Sleep hygiene for automobile drivers remains an important concept to address. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Grinding Wheel System

    Science.gov (United States)

    Malkin, Stephen; Gao, Robert; Guo, Changsheng; Varghese, Biju; Pathare, Sumukh

    2003-08-05

    A grinding wheel system includes a grinding wheel with at least one embedded sensor. The system also includes an adapter disk containing electronics that process signals produced by each embedded sensor and that transmits sensor information to a data processing platform for further processing of the transmitted information.

  3. Recovery tread wheel pairs of machining

    Directory of Open Access Journals (Sweden)

    Igor IVANOV

    2013-01-01

    Full Text Available The basic methods of resurfacing wheels are determined and analised. It’sshown that for raising resource of used wheels and decreasing requirements of railwaytransport for new wheels it’s reasonable to use methods of recovering not only geometricparameters of rim, but also its mechanical properties. It’s marked that use of infeedprofile high-speed grinding (VPVSh enables to intensify significantly process ofmechanical treatment of wheel rim profile both when its resurfacing in service and whenmanufacturing new wheel.

  4. Visual Prediction of Rover Slip: Learning Algorithms and Field Experiments

    Science.gov (United States)

    2008-01-01

    of the terrain slope [29]. The results are also specific to the vehicle. For example, a small design modification in the pattern of the wheels can...robot has two front differential drive wheels and two rear caster wheels . 2This difference is not directly relevant to the goals of this work. 22 Figure...rover pose and is a quantity which measures the lack of progress of a wheeled ground robot while traversing some terrain. A trivial example of large

  5. Wheeling in Canada

    International Nuclear Information System (INIS)

    Fytche, E.L.

    1991-01-01

    The quest for economic efficiency, or lowest cost, in the electricity supply industry is furthered by trading between high and low cost utilities, one aspect being transporting or wheeling power through the transmission system of a third party. Some of the pressures and constraints limiting wheeling are discussed. A simple formula is presented for determining whether trading and wheeling are worthwhile. It is demonstrated for assumed capital and operating cost levels, the viability of nine cases where bulk power or economy energy would need to be wheeled across provincial boundaries in order to reach potential buyers. Wheeling in Canada is different from the situation in the USA, due to large distances spanned by Canadian utilities and because most are provincial crown corporations, with different territorial interests and profit motivations than investor-owned utilities. Most trading in electricity has been between contiguous neighbours, for mutual advantage. New technology allows power transmission over distances of up to 1000 miles, and the economics of Canada's electrical supply could be improved, with means including access to low cost coal of Alberta, and remote hydro in British Columbia, Manitoba, Quebec and Labrador. Nuclear plants could be located anywhere but suffer from an unfriendly public attitude. A bridge across the Prairies appears uneconomic due to cost of transmission, and also due to low valuation given to Alberta coal. 7 refs., 2 figs., 3 tabs

  6. The hydraulic wheel

    International Nuclear Information System (INIS)

    Alvarez Cardona, A.

    1985-01-01

    The present article this dedicated to recover a technology that key in disuse for the appearance of other techniques. It is the hydraulic wheel with their multiple possibilities to use their energy mechanical rotational in direct form or to generate electricity directly in the fields in the place and to avoid the high cost of transport and transformation. The basic theory is described that consists in: the power of the currents of water and the hydraulic receivers. The power of the currents is determined knowing the flow and east knowing the section of the flow and its speed; they are given you formulate to know these and direct mensuration methods by means of floodgates, drains and jumps of water. The hydraulic receivers or properly this hydraulic wheels that are the machines in those that the water acts like main force and they are designed to transmit the biggest proportion possible of absolute work of the water, the hydraulic wheels of horizontal axis are the common and they are divided in: you rotate with water for under, you rotate with side water and wheels with water for above. It is analyzed each one of them, their components are described; the conditions that should complete to produce a certain power and formulate them to calculate it. There are 25 descriptive figures of the different hydraulic wheels

  7. Design Study for Controllable Electric Motor for Three Wheel Drive, In Wheel Mounting on Professional, Electric, Lawn Mower

    DEFF Research Database (Denmark)

    Lu, Kaiyuan

    Design of a new generation of electric drive motor for professional lawnmowers forms the basic objective of this thesis. Modern drive concepts produces a growing demand for electrical machines featuring high torque density, and suitable for direct drive applications. Much attention is presently...... focused upon the transverse flux permanent magnet machine, which attracts great interests in electric and hybrid propulsion systems. This thesis deals with modelling, performance analysis, design, test and measurement of permanent magnet transverse flux machines (PMTFM). It is important to understand...... the main aspects that influence the behaviour of a PMTFM, as this may lead to improved designs of PMTFM or may reveal the limitations of the transverse flux technology. Generally, in PMTFM, the flux has a complex 3D pattern. Finite Element Method (FEM) needs to be used to analyse the magnetic field...

  8. Computation of wheel-rail contact force for non-mapping wheel-rail profile of Translohr tram

    Science.gov (United States)

    Ji, Yuanjin; Ren, Lihui; Zhou, Jinsong

    2017-09-01

    Translohr tram has steel wheels, in V-like arrangements, as guide wheels. These operate over the guide rails in inverted-V arrangements. However, the horizontal and vertical coordinates of the guide wheels and guide rails are not always mapped one-to-one. In this study, a simplified elastic method is proposed in order to calculate the contact points between the wheels and the rails. By transforming the coordinates, the non-mapping geometric relationship between wheel and rail is converted into a mapping relationship. Considering the Translohr tram's multi-point contact between the guide wheel and the guide rail, the elastic-contact hypothesis take into account the existence of contact patches between the bodies, and the location of the contact points is calculated using a simplified elastic method. In order to speed up the calculation, a multi-dimensional contact table is generated, enabling the use of simulation for Translohr tram running on curvatures with different radii.

  9. A novel mouse running wheel that senses individual limb forces: biomechanical validation and in vivo testing

    Science.gov (United States)

    Roach, Grahm C.; Edke, Mangesh

    2012-01-01

    Biomechanical data provide fundamental information about changes in musculoskeletal function during development, adaptation, and disease. To facilitate the study of mouse locomotor biomechanics, we modified a standard mouse running wheel to include a force-sensitive rung capable of measuring the normal and tangential forces applied by individual paws. Force data were collected throughout the night using an automated threshold trigger algorithm that synchronized force data with wheel-angle data and a high-speed infrared video file. During the first night of wheel running, mice reached consistent running speeds within the first 40 force events, indicating a rapid habituation to wheel running, given that mice generated >2,000 force-event files/night. Average running speeds and peak normal and tangential forces were consistent throughout the first four nights of running, indicating that one night of running is sufficient to characterize the locomotor biomechanics of healthy mice. Twelve weeks of wheel running significantly increased spontaneous wheel-running speeds (16 vs. 37 m/min), lowered duty factors (ratio of foot-ground contact time to stride time; 0.71 vs. 0.58), and raised hindlimb peak normal forces (93 vs. 115% body wt) compared with inexperienced mice. Peak normal hindlimb-force magnitudes were the primary force component, which were nearly tenfold greater than peak tangential forces. Peak normal hindlimb forces exceed the vertical forces generated during overground running (50-60% body wt), suggesting that wheel running shifts weight support toward the hindlimbs. This force-instrumented running-wheel system provides a comprehensive, noninvasive screening method for monitoring gait biomechanics in mice during spontaneous locomotion. PMID:22723628

  10. Development and validation of a new kind of coupling element for wheel-hub motors

    Science.gov (United States)

    Perekopskiy, Sergey; Kasper, Roland

    2018-05-01

    For the automotive industry, electric powered vehicles are becoming an increasingly relevant factor in the competition against climate change. Application of one special example - a wheel-hub motor, for electric powered vehicle can support this challenge. Patented slotless air gap winding invented at the chair of mechatronics of the Otto von Guericke University Magdeburg has great application potential in constantly growing e-mobility field, especially for wheel-hub motors based on this technology due to its advantages, such as a high gravimetric power density and high efficiency. However, advantages of this technology are decreased by its sensibility to the loads out of driving maneuvers by dimensional variations of air gap consistency. This article describes the development and validation of a coupling element for the designed wheel-hub motor. To find a suitable coupling concept first the assembly structure of the motor was analyzed and developed design of the coupling element was checked. Based on the geometry of the motor and wheel a detailed design of the coupling element was generated. The analytical approach for coupling element describes a potential of the possible loads on the coupling element. The FEM simulation of critical load cases for the coupling element validated results of the analytical approach.

  11. Naturalistic Teenage Driving Study: Findings and Lessons Learned

    Science.gov (United States)

    Simons-Morton, Bruce G.; Klauer, Sheila G.; Ouimet, Marie Claude; Guo, Feng; Albert, Paul S.; Lee, Suzanne E.; Ehsani, Johnathon P.; Pradhan, Anuj K.; Dingus, Thomas A.

    2015-01-01

    Problem This paper summarizes the findings on novice teenage driving outcomes (e.g., crashes and risky driving behaviors) from the Naturalistic Teenage Driving Study. Method Survey and driving data from a data acquisition system (Global Positioning System, accelerometers, cameras) were collected from 42 newly-licensed teenage drivers and their parents during the first 18 months of teenage licensure; stress responsivity was also measured in teenagers. Result Overall teenage crash and near crash (CNC) rates declined over time, but were >4 times higher among teenagers than adults. Contributing factors to teenage CNC rates included secondary task engagement (e.g., distraction), kinematic risky driving, low stress responsivity, and risky social norms. Conclusion The data support the contention that the high novice teenage CNC risk is due both to inexperience and risky driving behavior, particularly kinematic risky driving and secondary task engagement. Practical Applications Graduated driver licensing policy and other prevention efforts should focus on kinematic risky driving, secondary task engagement, and risky social norms. PMID:26403899

  12. Wheel inspection system environment.

    Science.gov (United States)

    2008-11-18

    International Electronic Machines Corporation (IEM) has developed and is now marketing a state-of-the-art Wheel Inspection System Environment (WISE). WISE provides wheel profile and dimensional measurements, i.e. rim thickness, flange height, flange ...

  13. The prospects for retail wheeling

    International Nuclear Information System (INIS)

    O'Donnell, E.H.; Center, J.A.

    1992-01-01

    This paper as published is an outline of a presentation on retail wheeling of electric power. The topics discussed are development of increased wholesale transmission access, government regulatory policies on wholesale transmission, examples of past and present retail transmission access agreements, examples of Federal Energy Regulatory Commission jurisdiction over retail wheeling, and state policies on retail wheeling

  14. Pile Driving

    Science.gov (United States)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  15. Dynamics of a motor vehicle taking into consideration the interaction of wheels and road pavement surface

    Directory of Open Access Journals (Sweden)

    O. Prentkovskis

    2002-12-01

    Full Text Available The authors of this article focus on the simulation of the motor vehicle on a certain road and propose their specific solution of this problem. A mathematical model of the system “motor vehicle – road” is presented. The motor vehicle is simulated by concentrated masses interconnected by elastic and dissipative links. The presented model of the motor vehicle evaluates the movement of the motor vehicle body in space; the movement and turning of front and rear suspensions with respect to the body; the interaction of the wheel with the road pavement surface; the blocking of the wheel; the changing cohesive forces which influence the motor vehicle. The investigated road pavement surface is simulated by triangular finite elements, the certain height of road pavement surface roughness and the cohesion coefficients of road pavement surface and the motor vehicle wheel in the longitudinal and transverse directions of the wheel are selected in each finite element nodal point. The presented results illustrate: the motor vehicle movement trajectories braking at various initial conditions and on a certain pavement surface of the road section under investigation and the motor vehicle driving on the speed reduction bump (“sleeping policeman”.

  16. Estimation of the friction coefficient between wheel and rail surface using traction motor behaviour

    International Nuclear Information System (INIS)

    Zhao, Y; Liang, B; Iwnicki, S

    2012-01-01

    The friction coefficient between a railway wheel and rail surface is a crucial factor in maintaining high acceleration and braking performance of railway vehicles thus monitoring this friction coefficient is important. Restricted by the difficulty in directly measuring the friction coefficient, the creep force or creepage, indirect methods using state observers are used more frequently. This paper presents an approach using a Kalman filter to estimate the creep force and creepage between the wheel and rail and then to identify the friction coefficient using the estimated creep force-creepage relationship. A mathematic model including an AC motor, wheel and roller is built to simulate the driving system. The parameters are based on a test rig at Manchester Metropolitan University. The Kalman filter is designed to estimate the friction coefficient based on the measurements of the simulation model. Series of residuals are calculated through the comparison between the estimated creep force and theoretical values of different friction coefficient. Root mean square values of the residuals are used in the friction coefficient identification.

  17. Fill and spill drives runoff connectivity over frozen ground

    Science.gov (United States)

    Coles, A. E.; McDonnell, J. J.

    2018-03-01

    Snowmelt-runoff processes on frozen ground are poorly understood at the hillslope scale. This is especially true for hillslopes on the northern Great Plains of North America where long periods of snow-covered frozen ground with very shallow slopes mask any spatial patterns and process controls on connectivity and hillslope runoff generation. This study examines a 4.66 ha (46,600 m2) hillslope on the northern Great Plains during the 2014 spring snowmelt season to explore hillslope runoff processes. Specifically, we explore the spatial patterns of runoff production source areas and examine how surface topography and patterns of snow cover, snow water equivalent, soil water content, and thawed layer depth - which we measured on a 10 m grid across our 46,600 m2 hillslope - affect melt water partitioning and runoff connectivity. A key question was whether or not the controls on connectivity are consistent with the fill and spill mechanism found in rain-dominated and unfrozen soil domains. The contrast between the slow infiltration rates into frozen soil and the relatively fast rates of snowmelt delivery to the soil surface resulted in water accumulation in small depressions under the snowpack. Consequently, infiltration was minimal over the 12 day melt period. Instead, nested filling of micro- and meso-depressions was followed by macro-scale, whole-slope spilling. This spilling occurred when large patches of ponded water exceeded the storage capacity behind downslope micro barriers in the surface topography, and flows from them coalesced to drive a rapid increase in runoff at the hillslope outlet. These observations of ponded water and flowpaths followed mapable fill and spill locations based on 2 m resolution digital topographic analysis. Interestingly, while surface topography is relatively unimportant under unfrozen conditions at our site because of low relief and high infiltrability, surface topography shows episodically critical importance for connectivity and

  18. How youth get engaged: grounded-theory research on motivational development in organized youth programs.

    Science.gov (United States)

    Dawes, Nickki Pearce; Larson, Reed

    2011-01-01

    For youth to benefit from many of the developmental opportunities provided by organized programs, they need to not only attend but become psychologically engaged in program activities. This research was aimed at formulating empirically based grounded theory on the processes through which this engagement develops. Longitudinal interviews were conducted with 100 ethnically diverse youth (ages 14–21) in 10 urban and rural arts and leadership programs. Qualitative analysis focused on narrative accounts from the 44 youth who reported experiencing a positive turning point in their motivation or engagement. For 38 of these youth, this change process involved forming a personal connection. Similar to processes suggested by self-determination theory (Ryan & Deci, 2000), forming a personal connection involved youth's progressive integration of personal goals with the goals of program activities. Youth reported developing a connection to 3 personal goals that linked the self with the activity: learning for the future, developing competence, and pursuing a purpose. The role of purpose for many youth suggests that motivational change can be driven by goals that transcend self-needs. These findings suggest that youth need not enter programs intrinsically engaged--motivation can be fostered--and that programs should be creative in helping youth explore ways to form authentic connections to program activities.

  19. Four-Wheel Vehicle Suspension System

    Science.gov (United States)

    Bickler, Donald B.

    1990-01-01

    Four-wheel suspension system uses simple system of levers with no compliant components to provide three-point suspension of chassis of vehicle while maintaining four-point contact with uneven terrain. Provides stability against tipping of four-point rectangular base, without rocking contact to which rigid four-wheel frame susceptible. Similar to six-wheel suspension system described in "Articulated Suspension Without Springs" (NPO-17354).

  20. Alcohol badly affects eye movements linked to steering, providing for automatic in-car detection of drink driving.

    Science.gov (United States)

    Marple-Horvat, Dilwyn E; Cooper, Hannah L; Gilbey, Steven L; Watson, Jessica C; Mehta, Neena; Kaur-Mann, Daljit; Wilson, Mark; Keil, Damian

    2008-03-01

    Driving is a classic example of visually guided behavior in which the eyes move before some other action. When approaching a bend in the road, a driver looks across to the inside of the curve before turning the steering wheel. Eye and steering movements are tightly linked, with the eyes leading, which allows the parts of the brain that move the eyes to assist the parts of the brain that control the hands on the wheel. We show here that this optimal relationship deteriorates with levels of breath alcohol well within the current UK legal limit for driving. The eyes move later, and coordination reduces. These changes lead to bad performance and can be detected by an automated in-car system, which warns the driver is no longer fit to drive.

  1. Wind-powered wheel locomotion, initiated by leaping somersaults, in larvae of the southeastern beach tiger beetle (Cicindela dorsalis media.

    Directory of Open Access Journals (Sweden)

    Alan Harvey

    2011-03-01

    Full Text Available Rapid movement is challenging for elongate, soft-bodied animals with short or no legs. Leaping is known for only a few animals with this "worm-like" morphology. Wheel locomotion, in which the animal's entire body rolls forward along a central axis, has been reported for only a handful of animals worldwide. Here we present the first documented case of wind-powered wheel locomotion, in larvae of the coastal tiger beetle Cicindela dorsalis media. When removed from their shallow burrows, larvae easily can be induced to enter a behavioral sequence that starts with leaping; while airborne, larvae loop their body into a rotating wheel and usually either "hit the ground rolling" or leap again. The direction larvae wheel is closely related to the direction in which winds are blowing; thus, all our larvae wheeled up-slope, as winds at our study site consistently blew from sea to land. Stronger winds increased both the proportion of larvae wheeling, and the distance traveled, exceeding 60 m in some cases. In addition, the proportion of larvae that wheel and the distance traveled by wheeling larvae are significantly greater on smooth sandy beaches than on beach surfaces made rough and irregular by pedestrian, equestrian, and vehicular traffic. Like other coastal species of tiger beetles, C. dorsalis media has suffered major declines in recent years that are clearly correlated with increased human impacts. The present study suggests that the negative effects of beach traffic may be indirect, preventing larvae from escaping from predators using wheel locomotion by disrupting the flat, hard surface necessary for efficient wheeling.

  2. The Reaction Wheel Pendulum

    CERN Document Server

    Block, Daniel J; Spong, Mark W

    2007-01-01

    This monograph describes the Reaction Wheel Pendulum, the newest inverted-pendulum-like device for control education and research. We discuss the history and background of the reaction wheel pendulum and other similar experimental devices. We develop mathematical models of the reaction wheel pendulum in depth, including linear and nonlinear models, and models of the sensors and actuators that are used for feedback control. We treat various aspects of the control problem, from linear control of themotor, to stabilization of the pendulum about an equilibrium configuration using linear control, t

  3. Propulsion Wheel Motor for an Electric Vehicle

    Science.gov (United States)

    Figuered, Joshua M. (Inventor); Herrera, Eduardo (Inventor); Waligora, Thomas M. (Inventor); Bluethmann, William J. (Inventor); Farrell, Logan Christopher (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Winn, Ross Briant (Inventor); Eggleston, IV, Raymond Edward (Inventor); Guo, Raymond (Inventor); hide

    2016-01-01

    A wheel assembly for an electric vehicle includes a wheel rim that is concentrically disposed about a central axis. A propulsion-braking module is disposed within an interior region of the wheel rim. The propulsion-braking module rotatably supports the wheel rim for rotation about the central axis. The propulsion-braking module includes a liquid cooled electric motor having a rotor rotatable about the central axis, and a stator disposed radially inside the rotor relative to the central axis. A motor-wheel interface hub is fixedly attached to the wheel rim, and is directly attached to the rotor for rotation with the rotor. The motor-wheel interface hub directly transmits torque from the electric motor to the wheel rim at a 1:1 ratio. The propulsion-braking module includes a drum brake system having an electric motor that rotates a cam device, which actuates the brake shoes.

  4. Assessing the influence of wheel defects of a rolling stockon railway tracks

    Directory of Open Access Journals (Sweden)

    Loktev Aleksey Alekseevich

    2015-05-01

    - slides (potholes, etc.The motion of the wheels with irregularities on the surface of the rail leads to vertical oscillation of the wheel, resulting in the forces of inertia, which is an additional load on the rail. In case of movement of the wheel with isolated roughness on the tread surface of the slide there is a strike, having a very large additional impact on the rail. Such attacks can cause kinked rails, especially in the winter months when there is increased fragility of rail steel, because of lowered temperatures. This is an abnormal phenomenon and occurs relatively rarely, at a small number of isolated irregularities on a wheel of the rolling stock. As correlations connecting the contact force and local deformation in the interaction of the wheel-rail system, we use the quasi-static Hertz’s model, linear-elastic model and two elastoplastic contact models: Alexandrov-Kadomtsev and Kil’chevsky. According to the results of Loktev’s studies ratios of the contact Hertz’s theory are quite suitable for modeling the dynamic effects of wheel and rail for speeds up to 90 km/h for engineering calculations. Since the contact surface is homogeneous and isotropic, the friction forces in the contact zone are not taken into account, the size of the pad is small compared to the dimensions of the contacting bodies and characteristic radii of curvature of the undeformed surfaces, the contacting surfaces are smooth.When train is driving, the position of the wheelset in relation to the rails varies considerably, giving rise to different combinations of the contact areas of the wheel and rail. Even assuming constant axial load the normal voltage will vary considerably because of the differences in the radii of curvature of the contacting surfaces of these zones. Thus, the proposed method allows evaluating the influence of several types of wheel defects on the condition of the rail and the prospects of its use in the upper structure of a railway track on plots with different

  5. An examination of the concept of driving point receptance

    Science.gov (United States)

    Sheng, X.; He, Y.; Zhong, T.

    2018-04-01

    In the field of vibration, driving point receptance is a well-established and widely applied concept. However, as demonstrated in this paper, when a driving point receptance is calculated using the finite element (FE) method with solid elements, it does not converge as the FE mesh becomes finer, suggesting that there is a singularity. Hence, the concept of driving point receptance deserves a rigorous examination. In this paper, it is firstly shown that, for a point harmonic force applied on the surface of an elastic half-space, the Boussinesq formula can be applied to calculate the displacement amplitude of the surface if the response point is sufficiently close to the load. Secondly, by applying the Betti reciprocal theorem, it is shown that the displacement of an elastic body near a point harmonic force can be decomposed into two parts, with the first one being the displacement of an elastic half-space. This decomposition is useful, since it provides a solid basis for the introduction of a contact spring between a wheel and a rail in interaction. However, according to the Boussinesq formula, this decomposition also leads to the conclusion that a driving point receptance is infinite (singular), and would be undefinable. Nevertheless, driving point receptances have been calculated using different methods. Since the singularity identified in this paper was not appreciated, no account was given to the singularity in these calculations. Thus, the validity of these calculation methods must be examined. This constructs the third part of the paper. As the final development of the paper, the above decomposition is utilised to define and determine driving point receptances required for dealing with wheel/rail interactions.

  6. Engaging People who Drive Execution and Organizational Performance

    OpenAIRE

    Ologbo C. Andrew; Saudah Sofian

    2011-01-01

    Problem statement: The construct of employee engagement had gained much reputation in recent years among reputable management and human resources consulting firms. Though there is an increasing contributions of few academic research on the construct of employee engagement yet there is a shortage of academic studies on the construct. This gap had made the construct an interesting area of research. Approach: The purpose of this study is to test a model of the drivers of employee engagement on t...

  7. Enabling unmanned capabilities in the tactical wheeled vehicle fleet of the future

    Science.gov (United States)

    Zych, Noah

    2012-06-01

    From transporting troops and weapons systems to supplying beans, bullets, and Band-Aids to front-line warfighters, tactical wheeled vehicles serve as the materiel backbone anywhere there are boots on the ground. Drawing from the U.S. Army's Tactical Wheeled Vehicle Strategy and the Marine Corps Vision & Strategy 2025 reports, one may conclude that the services have modest expectations for the introduction of large unmanned ground systems into operational roles in the next 15 years. However, the Department of Defense has already invested considerably in the research and development of full-size UGVs-and commanders deployed in both Iraq and Afghanistan have advocated the urgent fielding of early incarnations of this technology, believing it could make a difference on their battlefields today. For military UGVs to evolve from mere tactical advantages into strategic assets with developed doctrine, they must become as trustworthy as a well-trained warfighter in performing their assigned task. Starting with the Marine Corps' ongoing Cargo Unmanned Ground Vehicle program as a baseline, and informed by feedback from previously deployed subject matter experts, this paper examines the gaps which presently exist in UGVs from a mission-capable perspective. It then considers viable near-term technical solutions to meet today's functional requirements, as well as long-term development strategies to enable truly robust performance. With future conflicts expected to be characterized by increasingly complex operational environments and a broad spectrum of rapidly adapting threats, one of the largest challenges for unmanned ground systems will be the ability to exhibit agility in unpredictable circumstances.

  8. E-drive with electrically controlled differential; E-Antrieb mit elektrisch geregeltem Differenzial

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, Tomas; Biermann, Thorsten [Schaeffler Technologies GmbH und Co. KG, Herzogenaurach (Germany); Rohe, Marco [AFT Atlas Fahrzeugtechnik GmbH, Werdohl (Germany); Heinrich, Wolfgang [IDAM, Suhl (Germany)

    2011-10-15

    Schaeffler is presenting an all-wheel drive electric vehicle named 'Active eDrive'. The name is intended principally to convey innovation and the USP of the drive system: an electric differential with a torque vectoring function. The system combines the final drive with intelligent transverse torque distribution which, when used on axles, enables the distribution of torque over the longitudinal axis of the vehicle. The final drive can be integrated in both electric and hybrid vehicles with or without a range extender capability. The authors first explain the mechanical requirements and then describe the electrical systems that are intended to fulfill these. (orig.)

  9. Asleep at the Wheel-The Road to Addressing Drowsy Driving.

    Science.gov (United States)

    Higgins, J Stephen; Michael, Jeff; Austin, Rory; Åkerstedt, Torbjörn; Van Dongen, Hans P A; Watson, Nathaniel; Czeisler, Charles; Pack, Allan I; Rosekind, Mark R

    2017-02-01

    Drowsy driving is a dangerous behavior that leads to thousands of deaths and injuries each year. It is also a controllable factor for drivers. Drivers are capable of modifying this behavior if given sufficient information and motivation. Our goal is to establish a comprehensive and strategic effort to end drowsy driving crashes and deaths. This article highlights some of the conclusions of a unique recent meeting of sleep experts and highway safety professionals and describes the first steps the community has taken and plans to take in the future to address this issue. Published by Oxford University Press on behalf of Sleep Research Society (SRS) 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  10. Wheel traffic effect on air-filled porosity and air permeability in a soil catena across the wheel rut

    DEFF Research Database (Denmark)

    Berisso, Feto Esimo; Schjønning, Per; Lamandé, Mathieu

    might induce different effects on soil physical properties. The objective of this study was to investigate the impact of vehicle traffic on soil physical properties and air permeability by systematic collection of samples in a transect running from the center to the outside of the wheel rut. A field...... catena running from center of the wheel rut to un wheeled part of the field ( 0, 20, 40, 50,60 and 400 cm horizontal distance). We measured water retention and air permeability (ka) at -30, -100 and -300 hPa matric potentials. At -100 hPa, we obtained consistently lower air filled under the wheel rut......The impact of wheel traffic on soil physical properties is usually quantified by randomly collecting soil cores at specific depths below the wheeled surface. However, modeling studies as well as few measurements indicated a non-uniform stress distribution in a catena across the wheel rut, which...

  11. Self-driving carsickness.

    Science.gov (United States)

    Diels, Cyriel; Bos, Jelte E

    2016-03-01

    This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and productivity. However, we here show that the envisaged scenarios all lead to an increased risk of motion sickness. As such, the benefits this technology is assumed to bring may not be capitalised on, in particular by those already susceptible to motion sickness. This can negatively affect user acceptance and uptake and, in turn, limit the potential socioeconomic benefits that this emerging technology may provide. Following a discussion on the causes of motion sickness in the context of self-driving cars, we present guidelines to steer the design and development of automated vehicle technologies. The aim is to limit or avoid the impact of motion sickness and ultimately promote the uptake of self-driving cars. Attention is also given to less well known consequences of motion sickness, in particular negative aftereffects such as postural instability, and detrimental effects on task performance and how this may impact the use and design of self-driving cars. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Fault diagnosis of direct-drive wind turbine based on support vector machine

    International Nuclear Information System (INIS)

    An, X L; Jiang, D X; Li, S H; Chen, J

    2011-01-01

    A fault diagnosis method of direct-drive wind turbine based on support vector machine (SVM) and feature selection is presented. The time-domain feature parameters of main shaft vibration signal in the horizontal and vertical directions are considered in the method. Firstly, in laboratory scale five experiments of direct-drive wind turbine with normal condition, wind wheel mass imbalance fault, wind wheel aerodynamic imbalance fault, yaw fault and blade airfoil change fault are carried out. The features of five experiments are analyzed. Secondly, the sensitive time-domain feature parameters in the horizontal and vertical directions of vibration signal in the five conditions are selected and used as feature samples. By training, the mapping relation between feature parameters and fault types are established in SVM model. Finally, the performance of the proposed method is verified through experimental data. The results show that the proposed method is effective in identifying the fault of wind turbine. It has good classification ability and robustness to diagnose the fault of direct-drive wind turbine.

  13. Risk of Motor Vehicle Accidents Related to Sleepiness at the Wheel: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Bioulac, Stéphanie; Franchi, Jean-Arthur Micoulaud; Arnaud, Mickael; Sagaspe, Patricia; Moore, Nicholas; Salvo, Francesco; Philip, Pierre

    2017-10-01

    Sleepiness at the wheel is widely believed to be a cause of motor vehicle accidents. Nevertheless, a systematic review of studies investigating this relationship has not yet been published. The objective of this study was to quantify the relationship between sleepiness at the wheel and motor vehicle accidents. A systematic review was performed using Medline, Scopus, and ISI Web of Science. The outcome measure of interest was motor vehicle accident defined as involving four- or two-wheeled vehicles in road traffic, professional and nonprofessional drivers, with or without objective consequences. The exposure was sleepiness at the wheel defined as self-reported sleepiness at the wheel. Studies were included if they provided adjusted risk estimates of motor vehicle accidents related to sleepiness at the wheel. Risk estimates and 95% confidence intervals (95% CIs) were extracted and pooled as odds ratios (ORs) using a random-effect model. Heterogeneity was quantified using Q statistics and the I2 index. The potential causes of heterogeneity were investigated using meta-regressions. Ten cross-sectional studies (51,520 participants), six case-control studies (4904 participants), and one cohort study (13,674 participants) were included. Sleepiness at the wheel was associated with an increased risk of motor vehicle accidents (pooled OR 2.51 [95% CI 1.87; 3.39]). A significant heterogeneity was found between the individual risk estimates (Q = 93.21; I2 = 83%). Sleepiness at the wheel increases the risk of motor vehicle accidents and should be considered when investigating fitness to drive. Further studies are required to explore the nature of this relationship. PROSPERO 2015 CRD42015024805. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  14. Biaxial wheel/hub test facility. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, G.; Grubisic, V. [eds.

    2000-07-01

    The 4{sup th} meeting aims to exchange the experience and knowledge of engineers during several presentations and discussions about new developments required for a reliable, time and cost reducing validation of the wheel/hub assembly. Tremendous development of the wheel performance, described by the ratio of the rated load (kg) versus the wheel weight (kg) had taken place during the last 5000 years. Starting from the ratio of 3 for wooden 2-piece-disc-wheels in Mesopotamia it needed nearly 1000 years to increase the ratio to approx 5 at light-weight spoke wheels for fighting carriages, found in the grave of king Tutenchamon in Egypt. Modern light alloy wheels of commercial vehicles reach values up to 160 kg/kg. Additionally the comlex design of the modern systems for cars and commercial vehicles comprising wheel, brake, hub, bearing, spindle and hub carrier, including different materials and their treatment, fasteners, press-fits, require an appropriate testing procedure. The variable loading conditions, caused by operational wheel forces, brake and torque moments including heating, may result in changing tolerances and press-fits during operation and consequently in different damage mechanisms. This can be simulated in the Biaxial Wheel Test Machine, whereby corresponding load programs are necessary. An overview about all biaxial test machines in usage at the end of 1999 is shown in the introduction. The total number is 17 for cars, 7 for commercial vehicles and 1 for trains. The six presentations of this meeting were consequently concentrated on: (a) recommendations for a standardization of load programs of the German Wheel Committee, (b) the simulation of brake and torque events and (c) the possibility for a numerical stress analyses and fatigue life assessment. (orig./AKF)

  15. A Nontoxic Barlow's Wheel

    Science.gov (United States)

    Daffron, John A.; Greenslade, Thomas B.

    2015-01-01

    Barlow's wheel has been a favorite demonstration since its invention by Peter Barlow (1776-1862) in 1822.1 In the form shown in Fig. 1, it represents the first electric motor. The interaction between the electric current passing from the axle of the wheel to the rim and the magnetic field produced by the U-magnet produces a torque that turns the wheel. The original device used mercury to provide electrical contact to the rim, and the dangers involved with the use of this heavy metal have caused the apparatus to disappear from the lecture hall.

  16. Analysis of Vehicle Steering and Driving Bifurcation Characteristics

    Directory of Open Access Journals (Sweden)

    Xianbin Wang

    2015-01-01

    Full Text Available The typical method of vehicle steering bifurcation analysis is based on the nonlinear autonomous vehicle model deriving from the classic two degrees of freedom (2DOF linear vehicle model. This method usually neglects the driving effect on steering bifurcation characteristics. However, in the steering and driving combined conditions, the tyre under different driving conditions can provide different lateral force. The steering bifurcation mechanism without the driving effect is not able to fully reveal the vehicle steering and driving bifurcation characteristics. Aiming at the aforementioned problem, this paper analyzed the vehicle steering and driving bifurcation characteristics with the consideration of driving effect. Based on the 5DOF vehicle system dynamics model with the consideration of driving effect, the 7DOF autonomous system model was established. The vehicle steering and driving bifurcation dynamic characteristics were analyzed with different driving mode and driving torque. Taking the front-wheel-drive system as an example, the dynamic evolution process of steering and driving bifurcation was analyzed by phase space, system state variables, power spectral density, and Lyapunov index. The numerical recognition results of chaos were also provided. The research results show that the driving mode and driving torque have the obvious effect on steering and driving bifurcation characteristics.

  17. Problems of locomotive wheel wear in fleet replacement

    Directory of Open Access Journals (Sweden)

    L.P. Lingaytis

    2013-08-01

    Full Text Available Purpose. To conduct a research and find out the causes of defects appearing on the wheel thread of freight locomotives 2М62 and SIEMENS ER20CF. Methodology. To find the ways to solve this problem comparing the locomotive designs and their operating conditions. Findings. After examining the nature of the wheel wear the main difference was found: in locomotives of the 2M62 line wears the wheel flange, and in the locomotives SIEMENS ER20CF – the tread surface. After installation on the 2M62 locomotive the lubrication system of flanges their wear rate significantly decreased. On the new freight locomotives SIEMENS ER20CF the flange lubrication systems of the wheel set have been already installed at the factory, however the wheel thread is wearing. As for locomotives 2M62, and on locomotives SIEMENS ER20CF most wear profile skating wheels of the first wheel set. On both locomotive lines the 2М62 and the SIEMENS ER20CF the tread profile of the first wheel set most of all is subject to the wear. After reaching the 170 000 km run, the tread surface of some wheels begins to crumble. There was a suspicion that the reason for crumb formation of the wheel surface may be insufficient or excessive wheel hardness or its chemical composition. In order to confirm or deny this suspicion the following studies were conducted: the examination of the rim surface, the study of the wheel metal hardness and the document analysis of the wheel production and their comparison with the results of wheel hardness measurement. Practical value. The technical condition of locomotives is one of the bases of safety and reliability of the rolling stock. The reduction of the wheel wear significantly reduces the operating costs of railway transport. After study completion it was found that there was no evidence to suggest that the ratio of the wheel-rail hardness could be the cause of the wheel surface crumbling.

  18. Reaction wheels for kinetic energy storage

    Science.gov (United States)

    Studer, P. A.

    1984-11-01

    In contrast to all existing reaction wheel implementations, an order of magnitude increase in speed can be obtained efficiently if power to the actuators can be recovered. This allows a combined attitude control-energy storage system to be developed with structure mounted reaction wheels. The feasibility of combining reaction wheels with energy storage wwheels is demonstrated. The power required for control torques is a function of wheel speed but this energy is not dissipated; it is stored in the wheel. The I(2)R loss resulting from a given torque is shown to be constant, independent of the design speed of the motor. What remains, in order to efficiently use high speed wheels (essential for energy storage) for control purposes, is to reduce rotational losses to acceptable levels. Progress was made in permanent magnet motor design for high speed operation. Variable field motors offer more control flexibility and efficiency over a broader speed range.

  19. Customer loads of two-wheeled vehicles

    Science.gov (United States)

    Gorges, C.; Öztürk, K.; Liebich, R.

    2017-12-01

    Customer usage profiles are the most unknown influences in vehicle design targets and they play an important role in durability analysis. This publication presents a customer load acquisition system for two-wheeled vehicles that utilises the vehicle's onboard signals. A road slope estimator was developed to reveal the unknown slope resistance force with the help of a linear Kalman filter. Furthermore, an automated mass estimator was developed to consider the correct vehicle loading. The mass estimation is performed by an extended Kalman filter. Finally, a model-based wheel force calculation was derived, which is based on the superposition of forces calculated from measured onboard signals. The calculated wheel forces were validated by measurements with wheel-load transducers through the comparison of rainflow matrices. The calculated wheel forces correspond with the measured wheel forces in terms of both quality and quantity. The proposed methods can be used to gather field data for improved vehicle design loads.

  20. Assessment of a Boat Fractured Steering Wheel

    Directory of Open Access Journals (Sweden)

    Vukelic Goran

    2016-09-01

    Full Text Available During regular use of the steering wheel mounted on a boat, two cracks emanating from a fastener hole were noticed which, consequently, caused final fracture of the wheel. To determine the behavior of a boat steering wheel with cracks present, assessment of a fractured wheel was performed. Torque moments of the fasteners were measured prior to removing the steering wheel from the boat. Visual and dye penetrant inspection followed along with the material detection. Besides using experimental procedures, assessment of the fractured wheel was performed using finite element analysis, i.e. stress intensity factor values were numerically determined. Variation of stress intensity factor with crack length is presented. Possible causes of crack occurrence are given and they include excessive values of fastener torque moments coupled with fretting between fastener and fastener hole that was poorly machined. Results obtained by this assessment can be taken for predicting fracture behavior of a cracked steering wheel and as a reference in the design, mounting and exploitation process of steering wheels improving that way their safety in transportation environment.

  1. Solar wheel chair; Solar kurumaisu (iryokei no tachiba kara no kokoromi)

    Energy Technology Data Exchange (ETDEWEB)

    Okabe, K [Gunma Prefectural College of Health Sciences, Gunma (Japan)

    1996-10-27

    Physically handicapped people due to accidents for example have been increasing yearly in number with the increase of the aged, spread of cars, and change in the living environment. Therefore, participation in society by such people as called the weak is indispensable. Under the circumstances, as a means of their participation, a wheel chair as a moving aid was examined from the viewpoint of medical treatment and classified into three categories as follows: (1) for the use of the aged who are healthy but leg muscles are weak, (2) for the use of the invalid incapable of moving a part of the body and (3) for the use in sports by people who are disabled in the lower half of the body but healthy otherwise. In other words, prototypes were made for three kinds of solar wheel chair, for the aged, for the invalid and for sport use by the disabled, with a field test performed for each prototype. The wheel chairs were exhibited in the school, used in welfare facilities and driven by a disabled person who participated in 100km marathon. The users` opinions were favorable stating they were able to drive by themselves the new vehicle utilizing the clean energy and to move around by their own free will. 6 refs., 5 figs.

  2. An Ultrasonic Wheel-Array Probe

    Science.gov (United States)

    Drinkwater, B. W.; Brotherhood, C. J.; Freemantle, R. J.

    2004-02-01

    This paper describes the development and modeling of an ultrasonic array wheel probe scanning system. The system operates at 10 MHz using a 64 element array transducer which is 50 mm in length and located in a fluid filled wheel. The wheel is coupled to the test structure dry, or with a small amount of liquid couplant. When the wheel is rolled over the surface of the test structure a defect map (C-Scan) is generated in real-time. The tyre is made from a soft, durable polymer which has very little acoustic loss. Two application studies are presented; the inspection of sealant layers in an aluminum aircraft wing structure and the detection of embedded defects in a thick section carbon composite sample.

  3. Development of iFab (Instant Foundry Adaptive Through Bits) Manufacturing Process and Machine Library

    Science.gov (United States)

    2012-08-01

    input shaft , pump, gearbox, rack & pinion… Wheel assy wheel, tire, drive hub, lug, spindle , bearing… Braking brake disc/drum, caliper, friction...processes and associated machines is provided. Progress with respect to Task 3 (to design and develop the Manufacturing Capability Modeling Environment...of Military Ground Vehicle Design , Materials, and Processes ............... 4 4.2 Task 2 Manufacturing Knowledge Characterization

  4. Analysis of the individual factors affecting mobile phone use while driving in France: socio-demographic characteristics, car and phone use in professional and private contexts.

    Science.gov (United States)

    Brusque, Corinne; Alauzet, Aline

    2008-01-01

    In France, as in many other countries, phoning while driving is legally restricted because of its negative impact on driving performance which increases accident risk. Nevertheless, it is still a frequently observed practice and one which has not been analyzed in detail. This study attempts to identify the profiles of those who use mobile phones while at the wheel and determine the forms taken by this use. A representative sample of 1973 French people was interviewed by phone on their driving practices and mobile phone use in everyday life and their mobile phone use while driving. Logistics regressions have been conducted to highlight the explanatory factors of phoning while driving. Strong differences between males and females have been shown. For the male population, age is the main explanatory factor of phoning while driving, followed by phone use for work-related reasons and extensive mobile phone use in everyday life. For females, high mileage and intensive use of mobile phone are the only two explanatory factors. We defined the intensive phone use at the wheel group as drivers who receive or send at least five or more calls per day while driving. There is no socio-demographic variable related to this practice. Car and phone uses in everyday life are the only explanatory factors for this intensive mobile use of the phone at the wheel.

  5. Wheeled hopping robot

    Science.gov (United States)

    Fischer, Gary J [Albuquerque, NM

    2010-08-17

    The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

  6. Anti-slip-control (ASR) - a contribution to active driving safety. Antriebsschlupfreglung (ASR) - ein Beitrag zur aktiven Fahrsicherheit

    Energy Technology Data Exchange (ETDEWEB)

    Dorissen, T.; Hoever, N.

    1993-04-01

    Anti slip control is a method of reducing wheel spin if the torque at the driven wheels of a vehicle exceeds the available friction between road and tyre. As a result driving stability and traction can be optimized. Therefore, anti slip control systems offer improved roadholding and steering control while cornering on slippery surfaces, reduced tyre wear and a higher degree of driver comfort and confidence. In this paper Hella verifies that for front and also rear wheel driven vehicles a high performance anti slip control system, mainly designed for vehicle stability, is possible by throttle control. (orig./HW).

  7. 49 CFR 229.73 - Wheel sets.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Wheel sets. 229.73 Section 229.73 Transportation... TRANSPORTATION RAILROAD LOCOMOTIVE SAFETY STANDARDS Safety Requirements Suspension System § 229.73 Wheel sets. (a...) when applied or turned. (b) The maximum variation in the diameter between any two wheel sets in a three...

  8. Wheel arch aerodynamics of a modern road vehicle

    International Nuclear Information System (INIS)

    Apsley, S.; Aroussi, A.

    2003-01-01

    A geometrically faithful model of the Aston Martin V12 Vanquish was formed in 3D CAD and used to perform an extensive CFD study into the airflow in and around the wheel arch of the vehicle. Parameters such as spin ratio, ground clearance, vertical and horizontal insertion into the wheel arch and the yaw angles experienced during cornering, were all under investigation. The additional aim of the research was to validate or refute the use of CFD as a tool in this complex area of fluid flow. This research serves to highlight a number of problems and potential solutions in the use of CFD. Meshing problems can be eliminated with increased computational power and suggestions have been made to improve the modeling of rotating boundaries that include radial features such as wheel spokes. Much of the CFD data ties well with previously conducted experimental work, if not numerically then in trend. Without additional physical validation however, it is difficult to ascertain the overall accuracy and usefulness of the remaining results, which have not yet been conducted in physical reality. Despite its limitations, the use of CFD permitted an extensive analysis in a comparatively short length of time and served to highlight potential areas for increased scrutiny. As an example, results from the final yaw angle case drew attention to a potential concern for aerodynamic destabilisation of the vehicle during cornering, generating lift on the front arch of the car that is already lifted due to cornering forces and body roll. (author)

  9. Rotating target wheel system for super-heavy element production at ATLAS

    CERN Document Server

    Greene, J P; Falout, J; Janssens, R V F

    2004-01-01

    A new scattering chamber housing a large diameter rotating target wheel has been designed and constructed in front of the Fragment Mass Analyzer (FMA) for the production of very heavy nuclei (Z greater than 100) using beams from the Argonne Tandem Linear Accelerator System (ATLAS). In addition to the target and drive system, the chamber is extensively instrumented in order to monitor target performance and deterioration. Capabilities also exist to install rotating entrance and exit windows for gas cooling of the target within the scattering chamber. The design and initial tests are described.

  10. Desempenho operacional de trator com tração dianteira auxiliar na subsolagem de um inceptisol Performance of a front wheel drive tractor in the subsoiling operation in an inceptisol

    Directory of Open Access Journals (Sweden)

    Neyton de Oliveira Miranda

    2000-04-01

    Full Text Available Na subsolagem de um solo da ordem dos Inceptisol (Cambissolos usando um trator com tração dianteira auxiliar, foram comparados pneus de duas idades, duas rotações do motor e duas marchas, além do uso ou não do bloqueio do diferencial. Mediram-se velocidade de deslocamento, patinagem das rodas traseiras, tempo operacional teórico e consumo de combustível por hora e por área trabalhada. O uso do bloqueio do diferencial não influiu significativamente em nenhum parâmetro estudado e o de pneus novos resultou em desempenho do trator superior em relação aos pneus desgastados, para todos os parâmetros estudados. A rotação do motor de 1.800 rpm reduziu a patinagem e o consumo de combustível por hora e por área trabalhada em relação a 2.000 rpm, enquanto o uso da quarta marcha reduziu o tempo operacional teórico e o consumo de combustível por área trabalhada em relação à terceira marcha.In the subsoiling operation in an Inceptisol with a front wheel drive tractor, worn and new tyres, two engine speeds, two gear ratios and the use or not of the differential lock, were compared. Travel speed, rear wheel slip, theoretical field time, and fuel consumption per hour as well as per worked area were measured. The differential lock did not influence significantly any studied parameter. New tires were superior to worn ones for all parameters. Engine speed of 1800 rpm reduced wheel slip, fuel consumption per hour and per hectare compared with 2000 rpm. Fourth gear reduced the theoretical field time and fuel consumption per hectare compared to third gear.

  11. Minisatellite Attitude Guidance Using Reaction Wheels

    Directory of Open Access Journals (Sweden)

    Ion STROE

    2015-06-01

    Full Text Available In a previous paper [2], the active torques needed for the minisatellite attitude guidance from one fixed attitude posture to another fixed attitude posture were determined using an inverse dynamics method. But when considering reaction/momentum wheels, instead of this active torques computation, the purpose is to compute the angular velocities of the three reaction wheels which ensure the minisatellite to rotate from the initial to the final attitude. This paper presents this computation of reaction wheels angular velocities using a similar inverse dynamics method based on inverting Euler’s equations of motion for a rigid body with one fixed point, written in the framework of the x-y-z sequence of rotations parameterization. For the particular case A=B not equal C of an axisymmetric minisatellite, the two computations are compared: the active torques computation versus the computation of reaction wheels angular velocities ̇x , ̇y and ̇z. An interesting observation comes out from this numerical study: if the three reaction wheels are identical (with Iw the moment of inertia of one reaction wheel with respect to its central axis, then the evolutions in time of the products between Iw and the derivatives of the reaction wheels angular velocities, i.e. ̇ , ̇ and ̇ remain the same and do not depend on the moment of inertia Iw.

  12. Advanced emergency braking under split friction conditions and the influence of a destabilising steering wheel torque

    Science.gov (United States)

    Tagesson, Kristoffer; Cole, David

    2017-07-01

    The steering system in most heavy trucks is such that it causes a destabilising steering wheel torque when braking on split friction, that is, different friction levels on the two sides of the vehicle. Moreover, advanced emergency braking systems are now mandatory in most heavy trucks, making vehicle-induced split friction braking possible. This imposes higher demands on understanding how the destabilising steering wheel torque affects the driver, which is the focus here. Firstly, an experiment has been carried out involving 24 subjects all driving a truck where automatic split friction braking was emulated. Secondly, an existing driver-vehicle model has been adapted and implemented to improve understanding of the observed outcome. A common conclusion drawn, after analysing results, is that the destabilising steering wheel torque only has a small effect on the motion of the vehicle. The underlying reason is a relatively slow ramp up of the disturbance in comparison to the observed cognitive delay amongst subjects; also the magnitude is low and initially suppressed by passive driver properties.

  13. A New Superalloy Enabling Heavy Duty Gas Turbine Wheels for Improved Combined Cycle Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Detor, Andrew [General Electric Company, Niskayuna, NY (United States). GE Global Research; DiDomizio, Richard [General Electric Company, Niskayuna, NY (United States). GE Global Research; McAllister, Don [The Ohio State Univ., Columbus, OH (United States); Sampson, Erica [General Electric Company, Niskayuna, NY (United States). GE Global Research; Shi, Rongpei [The Ohio State Univ., Columbus, OH (United States); Zhou, Ning [General Electric Company, Niskayuna, NY (United States). GE Global Research

    2017-01-03

    The drive to increase combined cycle turbine efficiency from 62% to 65% for the next-generation advanced cycle requires a new heavy duty gas turbine wheel material capable of operating at 1200°F and above. Current wheel materials are limited by the stability of their major strengthening phase (gamma double prime), which coarsens at temperatures approaching 1200°F, resulting in a substantial reduction in strength. More advanced gamma prime superalloys, such as those used in jet engine turbine disks, are also not suitable due to size constraints; the gamma prime phase overages during the slow cooling rates inherent in processing thick-section turbine wheels. The current program addresses this need by screening two new alloy design concepts. The first concept exploits a gamma prime/gamma double prime coprecipitation reaction. Through manipulation of alloy chemistry, coprecipitation is controlled such that gamma double prime is used only to slow the growth of gamma prime during slow cooling, preventing over-aging, and allowing for subsequent heat treatment to maximize strength. In parallel, phase field modeling provides fundamental understanding of the coprecipitation reaction. The second concept uses oxide dispersion strengthening to improve on two existing alloys that exhibit excellent hold time fatigue crack growth resistance, but have insufficient strength to be considered for gas turbine wheels. Mechanical milling forces the dissolution of starting oxide powders into a metal matrix allowing for solid state precipitation of new, nanometer scale oxides that are effective at dispersion strengthening.

  14. Maximum Torque and Momentum Envelopes for Reaction Wheel Arrays

    Science.gov (United States)

    Markley, F. Landis; Reynolds, Reid G.; Liu, Frank X.; Lebsock, Kenneth L.

    2009-01-01

    Spacecraft reaction wheel maneuvers are limited by the maximum torque and/or angular momentum that the wheels can provide. For an n-wheel configuration, the torque or momentum envelope can be obtained by projecting the n-dimensional hypercube, representing the domain boundary of individual wheel torques or momenta, into three dimensional space via the 3xn matrix of wheel axes. In this paper, the properties of the projected hypercube are discussed, and algorithms are proposed for determining this maximal torque or momentum envelope for general wheel configurations. Practical strategies for distributing a prescribed torque or momentum among the n wheels are presented, with special emphasis on configurations of four, five, and six wheels.

  15. Mechanical design of a free-wheel clutch for the thermal engine of a parallel hybrid vehicle with thermal and electrical power-train; Conception mecanique d'un accouplement a roue libre pour le moteur thermique d'un vehicule hybride parallele thermique et electrique

    Energy Technology Data Exchange (ETDEWEB)

    Santin, J.J.

    2001-07-01

    This thesis deals with the design of a free-wheel clutch. This unit is intended to replace the automated dry single-plate clutch of a parallel hybrid car with thermal and electric power-train. Furthermore, the car is a single shaft zero emission vehicle fitted with a controlled gearbox. Chapter one focuses on the type of hybrid vehicle studied. It shows the need to isolate the engine from the rest of the drive train, depending on the driving conditions. Chapter two presents and compares the two alternatives: automated clutch and free-wheel. In order to develop the free-wheel option, the torsional vibrations in the automotive drive line had to be closely studied. It required the design of a specific modular tool, as presented in chapter three, with the help of MATLAB SIMULINK. Lastly, chapter four shows how this tool was used during the design stage and specifies the way to build it. The free-wheel is then to be fitted to a prototype hybrid vehicle, constructed by both the LAMIH and PSA. (author)

  16. Why Animals Run on Legs, Not on Wheels.

    Science.gov (United States)

    Diamond, Jared

    1983-01-01

    Speculates why animals have not developed wheels in place of inefficient legs. One study cited suggests three reasons why animals are better off without wheels: wheels are efficient only on hard surfaces, limitation of wheeled motion due to vertical obstructions, and the problem of turning in spaces cluttered with obstacles. (JN)

  17. Frontend and Backend Electronics for the ATLAS New Small Wheel Upgrade

    CERN Document Server

    Martinez Outschoorn, Verena; The ATLAS collaboration

    2016-01-01

    The Phase-I and Phase-II upgrades of the LHC accelerator will increase the LHC instantaneous luminosity to 2×1034 cm-2s-1 and 7.5×1034 cm-2s-1, respectively. The luminosity increase drastically impacts the ATLAS trigger and readout data rates. The present ATLAS small wheel muon detector will be replaced with a New Small Wheel (NSW) detector in 2019. The NSW will feature two new detector technologies, Resistive Micromegas (MM) and small strip Thin Gap Chambers (sTGC) conforming a system of ~2.4 million readout channels. Both detectors will be used for muon triggering and precision tracking. A common readout path and two separate trigger paths are developed for these two detector technologies. The frontend electronics will be implemented in about 8000 boards including the design of 4 custom ASICs capable of driving trigger and tracking primitives to the backend trigger processor and readout system. The readout data flow is designed through a high-throughput network approach. The large number of readout channe...

  18. Driving Under the Influence (of Language).

    Science.gov (United States)

    Barrett, Daniel Paul; Bronikowski, Scott Alan; Yu, Haonan; Siskind, Jeffrey Mark

    2017-06-09

    We present a unified framework which supports grounding natural-language semantics in robotic driving. This framework supports acquisition (learning grounded meanings of nouns and prepositions from human sentential annotation of robotic driving paths), generation (using such acquired meanings to generate sentential description of new robotic driving paths), and comprehension (using such acquired meanings to support automated driving to accomplish navigational goals specified in natural language). We evaluate the performance of these three tasks by having independent human judges rate the semantic fidelity of the sentences associated with paths. Overall, machine performance is 74.9%, while the performance of human annotators is 83.8%.

  19. Group traction drive as means to increase energy efficiency of lokomotives of open-pit transport

    Science.gov (United States)

    Antipin, D. Ya; Izmerov, O. V.; Bishutin, S. G.; Kobishchanov, V. V.

    2017-10-01

    Questions of possible use of a group drive for locomotives of an open-pit transport are considered. The possibility of a significant reduction of traction costs in the case of a combination of a group traction drive with devices for the non-inertial regulation of the coefficient of friction between the wheel and the rail has been shown, and new patentable solutions have been proposed.

  20. Wheel set run profile renewing method effectiveness estimation

    OpenAIRE

    Somov, Dmitrij; Bazaras, Žilvinas; Žukauskaite, Orinta

    2010-01-01

    At all the repair enterprises, despite decreased rim wear-off resistance, after every grinding only geometry wheel profile parameters are renewed. Exploit wheel rim work edge decrease tendency is noticed what induces acquiring new wheels. This is related to considerable axle load and train speed increase and also because of wheel work edge repair method imperfection.

  1. 49 CFR 230.113 - Wheels and tire defects.

    Science.gov (United States)

    2010-10-01

    ... tires may not have a seam running lengthwise that is within 33/4 inches of the flange. (g) Worn flanges... 49 Transportation 4 2010-10-01 2010-10-01 false Wheels and tire defects. 230.113 Section 230.113... Tenders Wheels and Tires § 230.113 Wheels and tire defects. Steam locomotive and tender wheels or tires...

  2. METHODS OF NOISE LEVEL REDUCTION OF DRIVE IN LATHES

    Directory of Open Access Journals (Sweden)

    Janusz ROGULA

    2014-06-01

    Full Text Available The aim of this work is method presentation to noise level reduction of fixed headstock of the lathe. It is connected with the causes finding of non-uniform work of lathe headstock, description of recent design and its analysis. Problem of the excessive noise level concern to near 35% of the lathes have been produced. In spite of lack of noise reduction possibility there were no system solution of problem. Design optimisation weren’t done after application the electric motor with inverter. New solution of electric motor control let to reduce number of gear wheels in lathe drive system. For this drive solution there weren’t made the analysis of drive particular parts influence on the noise generation.

  3. Differing types of cellular phone conversations and dangerous driving.

    Science.gov (United States)

    Dula, Chris S; Martin, Benjamin A; Fox, Russell T; Leonard, Robin L

    2011-01-01

    This study sought to investigate the relationship between cell phone conversation type and dangerous driving behaviors. It was hypothesized that more emotional phone conversations engaged in while driving would produce greater frequencies of dangerous driving behaviors in a simulated environment than more mundane conversation or no phone conversation at all. Participants were semi-randomly assigned to one of three conditions: (1) no call, (2) mundane call, and, (3) emotional call. While driving in a simulated environment, participants in the experimental groups received a phone call from a research confederate who either engaged them in innocuous conversation (mundane call) or arguing the opposite position of a deeply held belief of the participant (emotional call). Participants in the no call and mundane call groups differed significantly only on percent time spent speeding and center line crossings, though the mundane call group consistently engaged in more of all dangerous driving behaviors than did the no call participants. Participants in the emotional call group engaged in significantly more dangerous driving behaviors than participants in both the no call and mundane call groups, with the exception of traffic light infractions, where there were no significant group differences. Though there is need for replication, the authors concluded that whereas talking on a cell phone while driving is risky to begin with, having emotionally intense conversations is considerably more dangerous. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Changes in self-reported driving intentions and attitudes while learning to drive in Great Britain.

    Science.gov (United States)

    Helman, S; Kinnear, N A D; McKenna, F P; Allsop, R E; Horswill, M S

    2013-10-01

    Novice drivers are overrepresented in traffic collisions, especially in their first year of solo driving. It is widely accepted that some driving behaviours (such as speeding and thrill-seeking) increase risk in this group. Increasingly research is suggesting that attitudes and behavioural intentions held in the pre-driver and learning stage are important in determining later driver behaviour in solo driving. In this study we examine changes in several self-reported attitudes and behavioural intentions across the learning stage in a sample of learner drivers in Great Britain. A sample of 204 learner drivers completed a self-report questionnaire near the beginning of their learning, and then again shortly after they passed their practical driving test. Results showed that self-reported intentions regarding speed choice, perceptions regarding skill level, and intentions regarding thrill-seeking (through driving) became less safe over this time period, while self-reported intentions regarding following distance and overtaking tendency became safer. The results are discussed with reference to models of driver behaviour that focus on task difficulty; it is suggested that the manner in which behind-the-wheel experience relates to the risk measures of interest may be the key determining factor in how these change over the course of learning to drive. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  5. Voluntary Wheel Running in Mice.

    Science.gov (United States)

    Goh, Jorming; Ladiges, Warren

    2015-12-02

    Voluntary wheel running in the mouse is used to assess physical performance and endurance and to model exercise training as a way to enhance health. Wheel running is a voluntary activity in contrast to other experimental exercise models in mice, which rely on aversive stimuli to force active movement. This protocol consists of allowing mice to run freely on the open surface of a slanted, plastic saucer-shaped wheel placed inside a standard mouse cage. Rotations are electronically transmitted to a USB hub so that frequency and rate of running can be captured via a software program for data storage and analysis for variable time periods. Mice are individually housed so that accurate recordings can be made for each animal. Factors such as mouse strain, gender, age, and individual motivation, which affect running activity, must be considered in the design of experiments using voluntary wheel running. Copyright © 2015 John Wiley & Sons, Inc.

  6. Does the Tempo of Music Impact Human Behavior Behind the Wheel?

    Science.gov (United States)

    Navarro, Jordan; Osiurak, François; Reynaud, Emanuelle

    2018-06-01

    Assess the influence of background music tempo on driving performance. Music with a fast tempo is known to increase the level of arousal, whereas the reverse is observed for slow music. The relationship between driving performance and level of arousal was expected to take the form of an inverted U-curve. Three experiments were undertaken to manipulate the musical background during driving. In Experiment 1, the driver's preferred music track played at its original and modified (plus or minus 30%) tempo were used together with the simple ticking of a metronome. In Experiment 2, music tracks of different tempos were played during driving. In Experiment 3, music tracks were categorized as arousing or relaxing based on the associated perceived level of arousal. Listening to music tended to influence drivers' performances in a car-following task by improving coherence and gain adjustments relative to the followed vehicle but simultaneously shortened the intervehicular time. Although the tempo of the music per se did not directly affect driving behavior, arousing music tracks improved drivers' adjustments to the followed vehicle (Experiment 3). The tempo of the music listened to behind the wheel was not found to influence driving behaviors. However, arousing music improved drivers' responsiveness to changes in the speed of the followed vehicle. However, this benefit was canceled out by a reduction in the drivers' intervehicle safety margin. Listening to arousing music while driving cannot be considered to improve road safety, at least in a car-following task without attentional impairments.

  7. Peculiarities of Clutch Forming Rails and Wheel Block Construction

    Science.gov (United States)

    Shiler, V. V.; Galiev, I. I.; Shiler, A. V.

    2018-03-01

    The clutch of the wheel and rail is significantly influenced by the design features of the standard wheel pair, which are manifested in the presence of "parasitic" slipping of the wheels along the rails during its movement. The purpose of the presented work is to evaluate new design solutions for wheel sets. The research was carried out using methods of comparative simulation modelling and physical prototyping. A new design of the wheel pair (block wheel pair) is proposed, which features an independent rotation of all surfaces of the wheels in contact with the rails. The block construction of the wheel pair forms open mechanical contours with the track gauge, which completely eliminates the "parasitic" slippage. As a result, in the process of implementing traction or braking forces, the coupling coefficient of the block construction of the wheel pair is significantly higher than that of existing structures. In addition, in the run-out mode, the resistance to movement of the block wheel pair is half as much. All this will allow one to significantly reduce the energy consumption for traction of trains, wear of track elements and crew, and to increase the speed and safety of train traffic.

  8. Modal Analysis of In-Wheel Motor-Driven Electric Vehicle Based on Bond Graph Theory

    Directory of Open Access Journals (Sweden)

    Di Tan

    2017-01-01

    Full Text Available A half-car vibration model of an electric vehicle driven by rear in-wheel motors was developed using bond graph theory and the modular modeling method. Based on the bond graph model, modal analysis was carried out to study the vibration characteristics of the electric vehicle. To verify the effectiveness of the established model, the results were compared to ones computed on the ground of modal analysis and Newton equations. The comparison shows that the vibration model of the electric vehicle based on bond graph theory not only is able to better compute the natural frequency but also can easily determine the deformation mode, momentum mode, and other isomorphism modes and describe the dynamic characteristics of an electric vehicle driven by in-wheel motors more comprehensively than other modal analysis methods.

  9. 29 CFR 1910.215 - Abrasive wheel machinery.

    Science.gov (United States)

    2010-07-01

    ... be securely fastened to the spindle and the bearing surface shall run true. When more than one wheel... 29 Labor 5 2010-07-01 2010-07-01 false Abrasive wheel machinery. 1910.215 Section 1910.215 Labor... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Machinery and Machine Guarding § 1910.215 Abrasive wheel machinery. (a...

  10. The effect of track load correlation on ground-borne vibration from railways

    Science.gov (United States)

    Ntotsios, Evangelos; Thompson, David; Hussein, Mohammed

    2017-08-01

    In predictions of ground-borne vibration from railways, it is generally assumed that the unevenness profile of the wheel and rail is fully correlated between the two rails and the two wheels of an axle. This leads to identical contact forces at the two rails and can allow further simplifications of the vehicle model, the track model and the track/ground interface conditions. In the present paper, the level of correlation of the track loading at the wheel/rail interface due to rail unevenness and its influence on predictions of ground vibration is investigated. The extent to which the unevenness of the two rails is correlated has been estimated from measurements of track geometry obtained with track recording vehicles for four different tracks. It was found that for wavelengths longer than about 3 m the unevenness of the two rails can be considered to be strongly correlated and in phase. To investigate the effect of this on ground vibration, an existing model expressed in the wavenumber-frequency domain is extended to include separate inputs on the two rails. The track is modelled as an infinite invariant linear structure resting on an elastic stratified half-space. This is excited by the gravitational loading of a passing train and the irregularity of the contact surfaces between the wheels and the rails. The railway model is developed in this work to be versatile so that it can account or discard the effect of load correlations on the two rails beside the effects of variation of the tractions across the width of the track-ground interface and the vehicle sprung mass, as well as the roll motion of the sleepers and the axle. A comparative analysis is carried out on the influence of these factors on the response predictions using numerical simulations. It is shown that, when determining the vibration in the free field, it is important to include in the model the traction variation across the track-ground interface and the non-symmetrical loading at the two rails that

  11. Module-based structure design of wheeled mobile robot

    Directory of Open Access Journals (Sweden)

    Z. Luo

    2018-02-01

    Full Text Available This paper proposes an innovative and systematic approach for synthesizing mechanical structures of wheeled mobile robots. The principle and terminologies used for the proposed synthesis method are presented by adopting the concept of modular design, isomorphic and non-isomorphic, and set theory with its associated combinatorial mathematics. The modular-based innovative synthesis and design of wheeled robots were conducted at two levels. Firstly at the module level, by creative design and analysing the structures of classic wheeled robots, a wheel module set containing four types of wheel mechanisms, a suspension module set consisting of five types of suspension frames and a chassis module set composed of five types of rigid or articulated chassis were designed and generalized. Secondly at the synthesis level, two kinds of structure synthesis modes, namely the isomorphic-combination mode and the non-isomorphic combination mode were proposed to synthesize mechanical structures of wheeled robots; which led to 241 structures for wheeled mobile robots including 236 novel ones. Further, mathematical models and a software platform were developed to provide appropriate and intuitive tools for simulating and evaluating performance of the wheeled robots that were proposed in this paper. Eventually, physical prototypes of sample wheeled robots/rovers were developed and tested so as to prove and validate the principle and methodology presented in this paper.

  12. A new energy-efficient control approach for astronomical telescope drive system

    Science.gov (United States)

    Zhou, W.; Wang, Y.

    2012-12-01

    Drive control makes the astronomical telescope accurately tracking celestial bodies in spite of external and internal disturbances, which is a key technique to the performance of telescopes. In this paper, we propose a nonlinear ad, aptive observer based on power reversible approach for high precision telescope position tracking. The nonlinear adaptive observer automatically estimates the disturbances in drive system, and the observed value is applied to compensate for the real disturbances. With greatly reduced disturbances, the control precision can be evidently improved. In conventional drive control, the brake device is often used to slow down the reaction wheel and may waste enormous energy. To avoid those disadvantages, an H-bridge is put forward for wheel speed regulation. Such H-bridge has four independent sections, and each section mainly consists of a power electronic switch and an anti-parallel diode. During the period of the mount slowing down, the armature current of drive motor goes through the two path-wise diodes to charge the battery. Thus, energy waste is avoided. Based on the disturbance compensation, an optimal controller is designed to minimize an evaluation function which is made up of a weighted sum of position errors and energy consumption.The outputs of the controller are applied to control the H-bridge. Simulations are performed in MATLAB language. The results show that high precision control can be obtained by the proposed approach. And the energy consumption will be remarkably reduced.

  13. The influence of drinking, texting, and eating on simulated driving performance.

    Science.gov (United States)

    Irwin, Christopher; Monement, Sophie; Desbrow, Ben

    2015-01-01

    . No difference in reaction time to visual stimuli was observed between baseline and experimental drives for any of the trial conditions. Participants' subjective ratings indicated that they perceived the texting while driving condition to be the most difficult despite similar magnitudes of impairment observed with the eating while driving condition. Distracting behaviors such as eating and texting while driving appear to negatively impact driving measures of lane position control and reaction time. These findings may have direct implications for motorists that engage in these types of distracting behaviors behind the wheel and for the safety of other road users.

  14. A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

    OpenAIRE

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the tw...

  15. Costs associated with wheeling

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Wheeling costs are incurred by all companies that experience a change in power flows over their transmission lines during a specific transaction, whether or not the lines of that company are part of the contract path. The costs of providing wheeling service differ from one system to another and from one kind of wheeling transaction to another. While most transactions may be completed using existing capacity, others may require an increase in line. Depending on the situation, some cost components may be high, low, negative, or not incurred at all. This article discusses two general categories of costs; transactional and capital. The former are all operation, maintenance and opportunity costs incurred in completing a specific transaction assuming the existence of adequate capacity. Capital costs are the costs of major new equipment purchases and lines necessary to provide any increased level of transmission services

  16. How do nurse academics value and engage with evidence-based practice across Australia: Findings from a grounded theory study.

    Science.gov (United States)

    Malik, Gulzar; McKenna, Lisa; Griffiths, Debra

    2016-06-01

    Integrating evidence-based practice (EBP) into undergraduate education and preparing future nurses to embrace EBP in clinical practice becomes paramount in today's complex and evolving healthcare environment. The role that EBP plays in the practical lives of nursing students will depend on the degree to which it is promoted by academics, how it is incorporated into courses and its application to clinical setting. Hence, nursing academics play a crucial role in influencing its integration into curricula. Drawn from a larger doctoral study, this paper presents findings discussing how nurse academics value and engage with EBP. Grounded theory was employed to explore processes used by nursing academics while incorporating EBP into teaching and learning practices. Twenty-three academics across Australian universities were interviewed. Nine were also observed while teaching undergraduate students. Data were collected from semi-structured interviews and non-participant observation. In keeping with the tenets of grounded theory, data collection and analysis continued until theoretical saturation was reached. In total, four categories emerged. This paper focuses on the category conceptualised as Valuing and Engaging with EBP. How nursing academics valued and engaged with EBP was closely associated with meanings they constructed around understanding it, attitudes and commitment to implementation while teaching and working clinically. Different opinions also existed in regard to what actually constituted EBP. However, they engaged with and valued EBP by keeping themselves up-to-date, being involved in research activities, using evidence in teaching, therefore leading by example. Participants identified a number of barriers influencing their engagement with EBP including heavy workloads, limited time, lack of commitment within their schools, lack of confidence with teaching EBP, and complexity of EBP application. Faculty clinical practice, committed academics, workload

  17. Teen Drinking and Driving: A Dangerous Mix. CDC Vitalsigns[TM

    Science.gov (United States)

    Centers for Disease Control and Prevention, 2012

    2012-01-01

    The percentage of teens in high school who drink and drive has decreased by more than half since 1991, but more can be done. Nearly one million high school teens drank alcohol and got behind the wheel in 2011. Teen drivers are 3 times more likely than more experienced drivers to be in a fatal crash. Drinking any alcohol greatly increases this risk…

  18. High-Performance Reaction Wheel Optimization for Fine-Pointing Space Platforms: Minimizing Induced Vibration Effects on Jitter Performance plus Lessons Learned from Hubble Space Telescope for Current and Future Spacecraft Applications

    Science.gov (United States)

    Hasha, Martin D.

    2016-01-01

    The Hubble Space Telescope (HST) applies large-diameter optics (2.5-m primary mirror) for diffraction-limited resolution spanning an extended wavelength range (approx. 100-2500 nm). Its Pointing Control System (PCS) Reaction Wheel Assemblies (RWAs), in the Support Systems Module (SSM), acquired an unprecedented set of high-sensitivity Induced Vibration (IV) data for 5 flight-certified RWAs: dwelling at set rotation rates. Focused on 4 key ratios, force and moment harmonic values (in 3 local principal directions) are extracted in the RWA operating range (0-3000 RPM). The IV test data, obtained under ambient lab conditions, are investigated in detail, evaluated, compiled, and curve-fitted; variational trends, core causes, and unforeseen anomalies are addressed. In aggregate, these values constitute a statistically-valid basis to quantify ground test-to-test variations and facilitate extrapolations to on-orbit conditions. Accumulated knowledge of bearing-rotor vibrational sources, corresponding harmonic contributions, and salient elements of IV key variability factors are discussed. An evolved methodology is presented for absolute assessments and relative comparisons of macro-level IV signal magnitude due to micro-level construction-assembly geometric details/imperfections stemming from both electrical drive and primary bearing design parameters. Based upon studies of same-size/similar-design momentum wheels' IV changes, upper estimates due to transitions from ground tests to orbital conditions are derived. Recommended HST RWA choices are discussed relative to system optimization/tradeoffs of Line-Of-Sight (LOS) vector-pointing focal-plane error driven by higher IV transmissibilities through low-damped structural dynamics that stimulate optical elements. Unique analytical disturbance results for orbital HST accelerations are described applicable to microgravity efforts. Conclusions, lessons learned, historical context/insights, and perspectives on future applications

  19. Analysis and Design of a Permanent Magnet Bi-Stable Electro-Magnetic Clutch Unit for In-Wheel Electric Vehicle Drives

    Directory of Open Access Journals (Sweden)

    Wanli Cai

    2015-06-01

    Full Text Available Clutches have been used in internal combustion vehicles and concentrated electric vehicles (EVs to smoothen impulsion while starting and shifting. This paper proposes a permanent magnet bi-stable electromagnetic clutch unit (PMBECU which is specially introduced into in-wheel EVs to make the rigid connection between hub and wheel more flexible. Firstly, the operation principle of the PMBECU is illustrated. Then, the basic magnetic circuit model is presented and analyzed, followed by optimal design of the main structural parameters by investigating the PM leakage flux coefficient. Further, according to the basic electromagnetic characteristics of the PMBECU, the current pulse supply is put forward, and the minimum pulse width which enables the operation of the PMBECU and its dynamic characteristics are analyzed by an improved finite element method. Finally, a prototype machine is manufactured and tested to validate all the analysis results.

  20. Definition of simulated driving tests for the evaluation of drivers' reactions and responses.

    Science.gov (United States)

    Bartolozzi, Riccardo; Frendo, Francesco

    2014-01-01

    This article aims at identifying the most significant measures in 2 perception-response (PR) tests performed at a driving simulator: a braking test and a lateral skid test, which were developed in this work. Forty-eight subjects (26 females and 22 males) with a mean age of 24.9 ± 3.0 years were enrolled for this study. They were asked to perform a drive on the driving simulator at the University of Pisa (Italy) following a specific test protocol, including 8-10 braking tests and 8-10 lateral skid tests. Driver input signals and vehicle model signals were recorded during the drives and analyzed to extract measures such as the reaction time, first response time, etc. Following a statistical procedure (based on analysis of variance [ANOVA] and post hoc tests), all test measures (3 for the braking test and 8 for the lateral skid test) were analyzed in terms of statistically significant differences among different drivers. The presented procedure allows evaluation of the capability of a given test to distinguish among different drivers. In the braking test, the reaction time showed a high dispersion among single drivers, leading to just 4.8 percent of statistically significant driver pairs (using the Games-Howell post hoc test), whereas the pedal transition time scored 31.9 percent. In the lateral skid test, 28.5 percent of the 2 × 2 comparisons showed significantly different reaction times, 19.5 percent had different response times, 35.2 percent had a different second peak of the steering wheel signal, and 33 percent showed different values of the integral of the steering wheel signal. For the braking test, which has been widely employed in similar forms in the literature, it was shown how the reaction time, with respect to the pedal transition time, can have a higher dispersion due to the influence of external factors. For the lateral skid test, the following measures were identified as the most significant for application studies: the reaction time for the reaction

  1. Study on design of light-weight super-abrasive wheel

    Science.gov (United States)

    Nohara, K.; Yanagihara, K.; Ogawa, M.

    2018-01-01

    Fixed-abrasive tool, also called a grinding wheel, is produced by furnacing abrasive compound which contains abrasive grains and binding powder such as vitrified materials or resins. Fixed-abrasive tool is installed on spindle of grinding machine. And it is given 1,800-2,000 min-1 of spindle rotation for the usage. The centrifugal fracture of the compound of fixed- abrasive tool is one of the careful respects in designing. In recent years, however, super-abrasive wheel as a fixed-abrasive tool has been developed and applied widely. One of the most characteristic respects is that metal is applied for the body of grinding-wheel. The strength to hold abrasive grain and the rigidity of wheel become stronger than those of general grinding wheel, also the lifespan of fixed-abrasive tool becomes longer. The weight of fixed-abrasive tool, however, becomes heavier. Therefore, when the super-abrasive wheel is used, the power consumption of spindle motor becomes larger. It also becomes difficult for the grinding-wheel to respond to sudden acceleration or deceleration. Thus, in order to reduce power consumption in grinding and to obtain quicker frequency response of super-abrasive wheel, the new wheel design is proposed. The design accomplishes 46% weight reduction. Acceleration that is one second quicker than that of conventional grinding wheel is obtained.

  2. WheelWalker: a foot-wheel driving exoskeleton for the alternate walk of paraplegic patients

    Directory of Open Access Journals (Sweden)

    Ma Qingchuan

    2017-01-01

    Full Text Available Upright walk is the fundamental need of paraplegic patients. In this study, we proposed a novel lower-limb exoskeleton for assisting the patients to walk alternately and further improve their engagement in the rehabilitation training. The exoskeleton was driven by a hub motor which was mounted under the foot, and a pair of custom-made crutch with wireless controller was used to control the walking condition of exoskeleton and maintain balance. This paper mainly introduced the general designing concept and detailed specifications of each modules of the exoskeleton. A pilot using experiment was performed on two healthy subjects to qualitatively analyse the capability of this exoskeleton when adopting different gaits. The results showed that the subjects with different body characteristics could complete continued walk by wearing this exoskeleton either in a three-point gait mode or four-point gait mode.

  3. Wind-Sculpted Vicinity After Opportunity's Sol 1797 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 111 meters (364 feet) on the 1,797th Martian day, or sol, of Opportunity's surface mission (Feb. 12, 2009). North is at the center; south at both ends. Tracks from the drive recede northward across dark-toned sand ripples in the Meridiani Planum region of Mars. Patches of lighter-toned bedrock are visible on the left and right sides of the image. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). This view is presented as a cylindrical projection with geometric seam correction.

  4. Car Gestures - Advisory warning using additional steering wheel angles.

    Science.gov (United States)

    Maag, Christian; Schneider, Norbert; Lübbeke, Thomas; Weisswange, Thomas H; Goerick, Christian

    2015-10-01

    Advisory warning systems (AWS) notify the driver about upcoming hazards. This is in contrast to the majority of currently deployed advanced driver assistance systems (ADAS) that manage emergency situations. The target of this study is to investigate the effectiveness, acceptance, and controllability of a specific kind of AWS that uses the haptic information channel for warning the driver. This could be beneficial, as alternatives for using the visual modality can help to reduce the risk of visual overload. The driving simulator study (N=24) compared an AWS based on additional steering wheel angle control (Car Gestures) with a visual warning presented in a simulated head-up display (HUD). Both types of warning were activated 3.5s before the hazard object was reached. An additional condition of unassisted driving completed the experimental design. The subjects encountered potential hazards in a variety of urban situations (e.g. a pedestrian standing on the curbs). For the investigated situations, subjective ratings show that a majority of drivers prefer visual warnings over haptic information via gestures. An analysis of driving behavior indicates that both warning approaches guide the vehicle away from the potential hazard. Whereas gestures lead to a faster lateral driving reaction (compared to HUD warnings), the visual warnings result in a greater safety benefit (measured by the minimum distance to the hazard object). A controllability study with gestures in the wrong direction (i.e. leading toward the hazard object) shows that drivers are able to cope with wrong haptic warnings and safety is not reduced compared to unassisted driving as well as compared to (correct) haptic gestures and visual warnings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Continuous Steering Stability Control Based on an Energy-Saving Torque Distribution Algorithm for a Four in-Wheel-Motor Independent-Drive Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Li Zhai

    2018-02-01

    Full Text Available In this paper, a continuous steering stability controller based on an energy-saving torque distribution algorithm is proposed for a four in-wheel-motor independent-drive electric vehicle (4MIDEV to improve the energy consumption efficiency while maintaining the stability in steering maneuvers. The controller is designed as a hierarchical structure, including the reference model level, the upper-level controller, and the lower-level controller. The upper-level controller adopts the direct yaw moment control (DYC, which is designed to work continuously during the steering maneuver to better ensure steering stability in extreme situations, rather than working only after the vehicle is judged to be unstable. An adaptive two-hierarchy energy-saving torque distribution algorithm is developed in the lower-level controller with the friction ellipse constraint as a basis for judging whether the algorithm needs to be switched, so as to achieve a more stable and energy-efficient steering operation. The proposed stability controller was validated in a co-simulation of CarSim and Matlab/Simulink. The simulation results under different steering maneuvers indicate that the proposed controller, compared with the conventional servo controller and the ordinary continuous controller, can reduce energy consumption up to 23.68% and improve the vehicle steering stability.

  6. Incorporating a Wheeled Vehicle Model in a New Monocular Visual Odometry Algorithm for Dynamic Outdoor Environments

    Science.gov (United States)

    Jiang, Yanhua; Xiong, Guangming; Chen, Huiyan; Lee, Dah-Jye

    2014-01-01

    This paper presents a monocular visual odometry algorithm that incorporates a wheeled vehicle model for ground vehicles. The main innovation of this algorithm is to use the single-track bicycle model to interpret the relationship between the yaw rate and side slip angle, which are the two most important parameters that describe the motion of a wheeled vehicle. Additionally, the pitch angle is also considered since the planar-motion hypothesis often fails due to the dynamic characteristics of wheel suspensions and tires in real-world environments. Linearization is used to calculate a closed-form solution of the motion parameters that works as a hypothesis generator in a RAndom SAmple Consensus (RANSAC) scheme to reduce the complexity in solving equations involving trigonometric. All inliers found are used to refine the winner solution through minimizing the reprojection error. Finally, the algorithm is applied to real-time on-board visual localization applications. Its performance is evaluated by comparing against the state-of-the-art monocular visual odometry methods using both synthetic data and publicly available datasets over several kilometers in dynamic outdoor environments. PMID:25256109

  7. Incorporating a Wheeled Vehicle Model in a New Monocular Visual Odometry Algorithm for Dynamic Outdoor Environments

    Directory of Open Access Journals (Sweden)

    Yanhua Jiang

    2014-09-01

    Full Text Available This paper presents a monocular visual odometry algorithm that incorporates a wheeled vehicle model for ground vehicles. The main innovation of this algorithm is to use the single-track bicycle model to interpret the relationship between the yaw rate and side slip angle, which are the two most important parameters that describe the motion of a wheeled vehicle. Additionally, the pitch angle is also considered since the planar-motion hypothesis often fails due to the dynamic characteristics of wheel suspensions and tires in real-world environments. Linearization is used to calculate a closed-form solution of the motion parameters that works as a hypothesis generator in a RAndom SAmple Consensus (RANSAC scheme to reduce the complexity in solving equations involving trigonometric. All inliers found are used to refine the winner solution through minimizing the reprojection error. Finally, the algorithm is applied to real-time on-board visual localization applications. Its performance is evaluated by comparing against the state-of-the-art monocular visual odometry methods using both synthetic data and publicly available datasets over several kilometers in dynamic outdoor environments.

  8. Jitter reduction of a reaction wheel by management of angular momentum using magnetic torquers in nano- and micro-satellites

    Science.gov (United States)

    Inamori, Takaya; Wang, Jihe; Saisutjarit, Phongsatorn; Nakasuka, Shinichi

    2013-07-01

    Nowadays, nano- and micro-satellites, which are smaller than conventional large satellites, provide access to space to many satellite developers, and they are attracting interest as an application of space development because development is possible over shorter time period at a lower cost. In most of these nano- and micro-satellite missions, the satellites generally must meet strict attitude requirements for obtaining scientific data under strict constraints of power consumption, space, and weight. In many satellite missions, the jitter of a reaction wheel degrades the performance of the mission detectors and attitude sensors; therefore, jitter should be controlled or isolated to reduce its effect on sensor devices. In conventional standard-sized satellites, tip-tilt mirrors (TTMs) and isolators are used for controlling or isolating the vibrations from reaction wheels; however, it is difficult to use these devices for nano- and micro-satellite missions under the strict power, space, and mass constraints. In this research, the jitter of reaction wheels is reduced by using accurate sensors, small reaction wheels, and slow rotation frequency reaction wheel instead of TTMs and isolators. The objective of a reaction wheel in many satellite missions is the management of the satellite's angular momentum, which increases because of attitude disturbances. If the magnitude of the disturbance is reduced in orbit or on the ground, the magnitude of the angular momentum that the reaction wheels gain from attitude disturbances in orbit becomes smaller; therefore, satellites can stabilize their attitude using only smaller reaction wheels or slow rotation speed, which cause relatively smaller vibration. In nano- and micro-satellite missions, the dominant attitude disturbance is a magnetic torque, which can be cancelled by using magnetic actuators. With the magnetic compensation, the satellite reduces the angular momentum that the reaction wheels gain, and therefore, satellites do

  9. First Wheel of the Hadronic EndCap Calorimeter Completed

    CERN Multimedia

    Oram, C.J.

    2002-01-01

    With the LAr calorimeters well advanced in module production, the attention is turning to Batiment 180 where the calorimeter modules are formed into complete detectors and inserted into their respective cryostats. For the Hadronic End Cap (HEC) Group the task in B180 is to assemble the wheels, rotate them into their final orientation, and put them onto the cradle in front of the End Cap Cryostat. These tasks have been completed for the first HEC wheel in the B180 End Cap Clean Room. Given that this wheel weighs 70 tons the group is very relieved to have established that these gymnastics with the wheel proceed in a routine fashion. To assemble a wheel we take modules that have already been cold tested, do the final electrical testing and locate them onto the HEC wheel assembly table. Four wheels are required in total, each consisting of 32 modules. Wheel assembly is done in the horizontal position, creating a doughnut-like object sitting on the HEC table. The first picture shows the last module being added ...

  10. A dead reckoning localization system for mobile robots using inertial sensors and wheel revolution encoding

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Bong Su; Moon, Woo Sung; Seo, Woo Jin; Baek, Kwang Ryul [Pusan National University, Busan (Korea, Republic of)

    2011-11-15

    Inertial navigation systems (INS) are composed of inertial sensors, such as accelerometers and gyroscopes. An INS updates its orientation and position automatically; it has an acceptable stability over the short term, however this stability deteriorates over time. Odometry, used to estimate the position of a mobile robot, employs encoders attached to the robot's wheels. However, errors occur caused by the integrative nature of the rotating speed and the slippage between the wheel and the ground. In this paper, we discuss mobile robot position estimation without using external signals in indoor environments. In order to achieve optimal solutions, a Kalman filter that estimates the orientation and velocity of mobile robots has been designed. The proposed system combines INS and odometry and delivers more accurate position information than standalone odometry.

  11. Science of driving.

    Science.gov (United States)

    2016-08-01

    The Science of Driving project focused on developing a collaborative relationship to develop curriculum units for middle school and high school students to engage them in exciting real-world scenarios. This effort involved faculty, staff, and student...

  12. Implementation evaluation of steering teens safe: engaging parents to deliver a new parent-based teen driving intervention to their teens.

    Science.gov (United States)

    Ramirez, Marizen; Yang, Jingzhen; Young, Tracy; Roth, Lisa; Garinger, Anne; Snetselaar, Linda; Peek-Asa, Corinne

    2013-08-01

    Parents play a fundamental role in teaching their children safe driving skills to reduce risk of motor vehicle crashes, the leading cause of death for teens. Steering Teens Safe is a new parent-based intervention that equips parents with communication skills to talk about, demonstrate, and practice safe driving behaviors and skills with their teens. This implementation evaluation focuses on a sample of 83 parents who delivered Steering Teens Safe to their teens. One-, 2- and 3-month follow-up assessments were conducted with intervention parents to evaluate the self-reported quantity and quality of talking about, demonstrating, and practicing safe driving goals with teens; perceived success and benefit of the program; and barriers to implementation. Over 3 months of follow-up, parents discussed driving goals with their teens for a median of 101.5 minutes. The most frequently addressed topics were general safety principles, including distracted driving, driving in bad weather, wearing a seat belt, and being a safe passenger. Parents spent a median of 30 minutes practicing safe driving skills such as changing lanes. Sixty-seven percent of parents talked to their children about rural road safety, but just 36% demonstrated and half practiced these skills with their teens. Barriers to implementation include time and opportunity barriers and resistant attitudes of their teens. However, barriers neither affected frequency of engagement nor parents' perceived benefit and comfort in delivering the program. Parents with time/opportunity barriers also had higher practice and demonstration times than parents without these barriers. Findings indicate high acceptability among parent implementers and promise for real-world delivery. Future studies are needed to assess intervention impact.

  13. Project considerations and design of systems for wheeling cogenerated power

    Energy Technology Data Exchange (ETDEWEB)

    Tessmer, R.G. Jr.; Boyle, J.R.; Fish, J.H. III; Martin, W.A.

    1994-08-01

    Wheeling electric power, the transmission of electricity not owned by an electric utility over its transmission lines, is a term not generally recognized outside the electric utility industry. Investigation of the term`s origin is intriguing. For centuries, wheel has been used to describe an entire machine, not just individual wheels within a machine. Thus we have waterwheel, spinning wheel, potter`s wheel and, for an automobile, wheels. Wheel as a verb connotes transmission or modification of forces and motion in machinery. With the advent of an understanding of electricity, use of the word wheel was extended to be transmission of electric power as well as mechanical power. Today, use of the term wheeling electric power is restricted to utility transmission of power that it doesn`t own. Cogeneration refers to simultaneous production of electric and thermal power from an energy source. This is more efficient than separate production of electricity and thermal power and, in many instances, less expensive.

  14. Dynamic Forces between the Rails and the Wheels of Railway Vehicle

    Directory of Open Access Journals (Sweden)

    Zdravko Peran

    2016-02-01

    Full Text Available The process of acquisition of the measured dynamic values of forces between the rails and the wheels on the real measurement train and the train tracks. The conversion of the measured values into the matrices and vectors enables numerous exact qualitative and quantitative studies of the dynamic phenomena behaviour. The paper shows the possibilities of using MATLAB computer tool. All the commands in the software are given and explained. Calculating of the empirical, normal and cumulative distribution on an example of the lateral force is given in detail. The new software is exactly verified mathematically and qualified for any further use. The developed software is the tool for the development of other two phases: software for the exact automatic evaluation of the maximum values of the dynamic values and software for the automatic approval of vehicles and railway due to the driving safety, loading tracks and driving comfort compared to the limited values regarding UI C CODE 518.

  15. Piezoelectric drive circuit

    Science.gov (United States)

    Treu, C.A. Jr.

    1999-08-31

    A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

  16. Anti-ejection system for control rod drives

    International Nuclear Information System (INIS)

    Matthews, J.C.

    1977-01-01

    A linearly movable latch mechanism is provided to move into engagement with a deformable collet whenever an undesired ejection of a leadscrew is initiated from a nuclear reactor mounted control rod drive. Such an undesired ejection would occur in the event of a rupture in a housing of the control rod drive. The collet is deformed by the linear movement of the latch mechanism to wedge itself against the leadscrew and prevent the ejection of the leadscrew from the housing. The latch mechanism is made to be controllably engageable with the leadscrew and when thus engaged to allow the leadscrew to move in a control direction while moving with the leadscrew to engage and deform the collet when the leadscrew moves in an ejection direction. 13 claims, 2 figures

  17. Phenomena of Foamed Concrete under Rolling of Aircraft Wheels

    Science.gov (United States)

    Jiang, Chun-shui; Yao, Hong-yu; Xiao, Xian-bo; Kong, Xiang-jun; Shi, Ya-jie

    2014-04-01

    Engineered Material Arresting System (EMAS) is an effective technique to reduce hazards associated with aircraft overrunning runway. In order to ascertain phenomena of the foamed concrete used for EMAS under rolling of aircraft wheel, a specially designed experimental setup was built which employed Boeing 737 aircraft wheels bearing actual vertical loads to roll through the foamed concrete. A number of experiments were conducted upon this setup. It is discovered that the wheel rolls the concrete in a pure rolling manner and crushes the concrete downwards, instead of crushing it forward, as long as the concrete is not higher than the wheel axle. The concrete is compressed into powder in-situ by the wheel and then is brought to bottom of the wheel. The powder under the wheel is loose and thus is not able to sustain wheel braking. It is also found that after being rolled by the wheel the concrete exhibits either of two states, i.e. either 'crushed through' whole thickness of the concrete or 'crushed halfway', depending on combination of strength of the concrete, thickness of the concrete, vertical load the wheel carries, tire dimension and tire pressure. A new EMAS design concept is developed that if an EMAS design results in the 'crushed through' state for the main gears while the 'crushed halfway' state for the nose gear, the arresting bed would be optimal to accommodate the large difference in strength between the nose gear and the main gear of an aircraft.

  18. Do the front wheels of your car really meet Ackermann's principle when driving in a bend of the road?

    NARCIS (Netherlands)

    Dijksman, E.A.

    1997-01-01

    In the past, a trapezi-formed four-bar has often been used to realize the unequal turning of these wheels. Geometrically, however, this deviates considerably from the required (relative) motion as dictated by Ackermann's Principle. A better mechanism to approximate this principle would be a six-bar

  19. A fully omnidirectional wheeled assembly for robotic vehicles

    International Nuclear Information System (INIS)

    Killough, S.M.; Pin, F.G.

    1990-01-01

    A large number of wheeled or tracked platform mechanisms have been studied and developed to provide their mobility capability to teleoperated and autonomous robot vehicles. This paper presents an original wheeled platform based on an orthogonal wheel assembly that provides a full (three-degrees-of-freedom) omnidirectionality of the platform without wheel slippage and with the capability for simultaneous motions in rotation and translation (including sideways movements). A schematic of the basic wheel assembly is shown. The motion of the assembly is unconstrained (freewheeling) in the direction parallel to the main assembly shaft, while it is constrained in the direction perpendicular to the shaft, being driven in this direction by rotation of the shaft. A prototype platform was constructed to demonstrate the feasibility of this new concept

  20. PD-like controller for delayed bilateral teleoperation of wheeled robots

    Science.gov (United States)

    Slawiñski, E.; Mut, V.; Santiago, D.

    2016-08-01

    This paper proposes a proportional derivative (PD)-like controller applied to the delayed bilateral teleoperation of wheeled robots with force feedback in face of asymmetric and varying-time delays. In contrast to bilateral teleoperation of manipulator robots, in these systems, there is a mismatch between the models of the master and slave (mobile robot), problem that is approached in this work, where the system stability is analysed. From this study, it is possible to infer the control parameters, depending on the time delay, necessary to assure stability. Finally, the performance of the delayed teleoperation system is evaluated through tests where a human operator drives a 3D simulator as well as a mobile robot for pushing objects.

  1. Reaction Wheel Disturbance Model Extraction Software - RWDMES

    Science.gov (United States)

    Blaurock, Carl

    2009-01-01

    The RWDMES is a tool for modeling the disturbances imparted on spacecraft by spinning reaction wheels. Reaction wheels are usually the largest disturbance source on a precision pointing spacecraft, and can be the dominating source of pointing error. Accurate knowledge of the disturbance environment is critical to accurate prediction of the pointing performance. In the past, it has been difficult to extract an accurate wheel disturbance model since the forcing mechanisms are difficult to model physically, and the forcing amplitudes are filtered by the dynamics of the reaction wheel. RWDMES captures the wheel-induced disturbances using a hybrid physical/empirical model that is extracted directly from measured forcing data. The empirical models capture the tonal forces that occur at harmonics of the spin rate, and the broadband forces that arise from random effects. The empirical forcing functions are filtered by a physical model of the wheel structure that includes spin-rate-dependent moments (gyroscopic terms). The resulting hybrid model creates a highly accurate prediction of wheel-induced forces. It accounts for variation in disturbance frequency, as well as the shifts in structural amplification by the whirl modes, as the spin rate changes. This software provides a point-and-click environment for producing accurate models with minimal user effort. Where conventional approaches may take weeks to produce a model of variable quality, RWDMES can create a demonstrably high accuracy model in two hours. The software consists of a graphical user interface (GUI) that enables the user to specify all analysis parameters, to evaluate analysis results and to iteratively refine the model. Underlying algorithms automatically extract disturbance harmonics, initialize and tune harmonic models, and initialize and tune broadband noise models. The component steps are described in the RWDMES user s guide and include: converting time domain data to waterfall PSDs (power spectral

  2. Optimal Electrical Energy Slewing for Reaction Wheel Spacecraft

    Science.gov (United States)

    Marsh, Harleigh Christian

    The results contained in this dissertation contribute to a deeper level of understanding to the energy required to slew a spacecraft using reaction wheels. This work addresses the fundamental manner in which spacecrafts are slewed (eigenaxis maneuvering), and demonstrates that this conventional maneuver can be dramatically improved upon in regards to reduction of energy, dissipative losses, as well as peak power. Energy is a fundamental resource that effects every asset, system, and subsystem upon a spacecraft, from the attitude control system which orients the spacecraft, to the communication subsystem to link with ground stations, to the payloads which collect scientific data. For a reaction wheel spacecraft, the attitude control system is a particularly heavy load on the power and energy resources on a spacecraft. The central focus of this dissertation is reducing the burden which the attitude control system places upon the spacecraft in regards to electrical energy, which is shown in this dissertation to be a challenging problem to computationally solve and analyze. Reducing power and energy demands can have a multitude of benefits, spanning from the initial design phase, to in-flight operations, to potentially extending the mission life of the spacecraft. This goal is approached from a practical standpoint apropos to an industry-flight setting. Metrics to measure electrical energy and power are developed which are in-line with the cost associated to operating reaction wheel based attitude control systems. These metrics are incorporated into multiple families of practical high-dimensional constrained nonlinear optimal control problems to reduce the electrical energy, as well as the instantaneous power burdens imposed by the attitude control system upon the spacecraft. Minimizing electrical energy is shown to be a problem in L1 optimal control which is nonsmooth in regards to state variables as well as the control. To overcome the challenge of nonsmoothness, a

  3. How patients with gout become engaged in disease management: a constructivist grounded theory study.

    Science.gov (United States)

    Howren, Alyssa; Cox, Susan M; Shojania, Kam; Rai, Sharan K; Choi, Hyon K; De Vera, Mary A

    2018-06-01

    Prior qualitative research on gout has focused primarily on barriers to disease management. Our objective was to use patients' perspectives to construct an explanatory framework to understand how patients become engaged in the management of their gout. We recruited a sample of individuals with gout who were participating in a proof-of-concept study of an eHealth-supported collaborative care model for gout involving rheumatology, pharmacy, and dietetics. Semistructured interviews were used. We analyzed transcripts using principles of constructivist grounded theory involving initial coding, focused coding and categorizing, and theoretical coding. Twelve participants with gout (ten males, two females; mean age, 66.5 ± 13.3 years) were interviewed. The analysis resulted in the construction of three themes as well as a framework describing the dynamically linked themes on (1) processing the diagnosis and management of gout, (2) supporting management of gout, and (3) interfering with management of gout. In this framework, patients with gout transition between each theme in the process of becoming engaged in the management of their gout and may represent potential opportunities for healthcare intervention. Findings derived from this study show that becoming engaged in gout management is a dynamic process whereby patients with gout experience factors that interfere with gout management, process their disease and its management, and develop the practical and perceptual skills necessary to manage their gout. By understanding this process, healthcare providers can identify points to adapt care delivery and thereby improve health outcomes.

  4. Control of wheeled mobile robot in restricted environment

    Science.gov (United States)

    Ali, Mohammed A. H.; En, Chang Yong

    2018-03-01

    This paper presents a simulation and practical control system for wheeled mobile robot in restricted environment. A wheeled mobile robot with 3 wheels is fabricated and controlled by proportional derivative active force control (PD-AFC) to move in a pre-planned restricted environment to maintain the tracking errors at zero level. A control system with two loops, outer by PD controller and inner loop by Active Force Control, are designed to control the wheeled mobile robot. Fuzzy logic controller is implemented in the Active force Control to estimate the inertia matrix that will be used to calculate the actual torque applied on the wheeled mobile robot. The mobile robot is tested in two different trajectories, namely are circular and straight path. The actual path and desired path are compared.

  5. Nonlinear analysis of the GFRP material wheel hub

    Directory of Open Access Journals (Sweden)

    Dong Yun-Feng

    2015-01-01

    Full Text Available In this paper, the current bicycle wheel was replaced by the ones which composed by the wheel hub with Glassfiber Reinforced Plastic (alkali free thin-walled cylinder material, hereinafter referred to as GFRP material and the protective components made up of rubber outer pneumatic pad. With the help of the basic theory of elastic-plastic mechanics, the finite element “Nonlinear buckling” analysis of the wheel was carried out. The results show that the maximum elastic deformation of the wheel hub and the critical value of buckling failure load were restricted by the elasticity under the condition of external loads. Considering with the tensile strength and elastic modulus of the GFRP value of the material, it is demonstrated that the material is feasible to be used for wheel hub.

  6. Spirit Begins Drive Around Home Plate

    Science.gov (United States)

    2009-01-01

    The hazard avoidance camera on the front of NASA's Mars Exploration Rover Spirit took this image after a drive by Spirit on the 1,829th Martian day, or sol, of Spirit's mission on the surface of Mars (Feb. 24, 2009). On Sol 1829, Spirit drove 6.29 meters (21 feet) northwestward, away from the northern edge of the low plateau called 'Home Plate.' The track dug by the dragged right-front wheel as the rover drove backward is visible in this image, receding toward the southeast. Rock layers of the northern slope of Home Plate are visible in the upper right portion of the image. In sols prior to 1829, the rover team had been trying to maneuver Spirit to climb onto the northern edge of Home Plate, ready to drive southward across the top of the plateau toward science destinations south of Home Plate. The Sol 1829 drive was the first move of a revised strategy to circle at least partway around Home Plate on the trek toward the sites south of the plateau.

  7. Meals on Wheels Association of America

    Science.gov (United States)

    ... Meals About Meals on Wheels Get Started The Issue The Problem & Our Solution Meals on Wheels Health Facts & Resources Senior Facts Map State Fact Sheets Research More Than a Meal Pilot Research Study Medicare Claims Analyses Policy Myths Hunger in Older Adults Take Action Volunteer Advocate #SAVELUNCH ...

  8. ANALYSIS OF FORMING TREAD WHEEL SETS

    Directory of Open Access Journals (Sweden)

    Igor IVANOV

    2017-09-01

    Full Text Available This paper shows the results of a theoretical study of profile high-speed grinding (PHSG for forming tread wheel sets during repair instead of turning and mold-milling. Significant disadvantages of these methods are low capacity to adapt to the tool and inhomogeneous structure of the wheel material. This leads to understated treatment regimens and difficulties in recovering wheel sets with thermal and mechanical defects. This study carried out modeling and analysis of emerging cutting forces. Proposed algorithms describe the random occurrence of the components of the cutting forces in the restoration profile of wheel sets with an inhomogeneous structure of the material. To identify the statistical features of randomly generated structures fractal dimension and the method of random additions were used. The multifractal spectrum formed is decomposed into monofractals by wavelet transform. The proposed method allows you to create the preconditions for controlling the parameters of the treatment process.

  9. Method of Controlling Steering of a Ground Vehicle

    Science.gov (United States)

    Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor)

    2016-01-01

    A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.

  10. Development of Diamond-like Carbon Fibre Wheel

    Institute of Scientific and Technical Information of China (English)

    魏源迁; 山口勝美; 洞口巌; 竹内雅之

    2004-01-01

    A unique diamond-like carbon (DLC) grinding wheel was developed, in which the DLC fibres were made by rolling Al sheets coated with DLC films and aligned normally to the grinding wheel surface by laminating Al sheets together with DLC fibres. In this paper, the formation process of DLC fibres and the fabrication process of a DLC fibre wheel were investigated. Many grinding experiments were also carried out on a precision NC plane milling machine using a newly developed DLC wheel. Grinding of specimens of silicon wafers, optical glasses, quartz, granites and hardened die steel SKD11 demonstrated the capabilities of nanometer surface finish. A smooth surface with a roughness value of Ra2.5nm (Ry26nm) was achieved.

  11. UT Biomedical Informatics Lab (BMIL) probability wheel

    Science.gov (United States)

    Huang, Sheng-Cheng; Lee, Sara; Wang, Allen; Cantor, Scott B.; Sun, Clement; Fan, Kaili; Reece, Gregory P.; Kim, Min Soon; Markey, Mia K.

    A probability wheel app is intended to facilitate communication between two people, an "investigator" and a "participant", about uncertainties inherent in decision-making. Traditionally, a probability wheel is a mechanical prop with two colored slices. A user adjusts the sizes of the slices to indicate the relative value of the probabilities assigned to them. A probability wheel can improve the adjustment process and attenuate the effect of anchoring bias when it is used to estimate or communicate probabilities of outcomes. The goal of this work was to develop a mobile application of the probability wheel that is portable, easily available, and more versatile. We provide a motivating example from medical decision-making, but the tool is widely applicable for researchers in the decision sciences.

  12. Effects of two hospital bed design features on physical demands and usability during brake engagement and patient transportation: a repeated measures experimental study.

    Science.gov (United States)

    Kim, Sunwook; Barker, Linsey M; Jia, Bochen; Agnew, Michael J; Nussbaum, Maury A

    2009-03-01

    Work-related musculoskeletal disorders (WMSDs) are prevalent among healthcare workers worldwide. While existing research has focused on patient-handling techniques during activities which require direct patient contact (e.g., patient transfer), nursing tasks also involve other patient-handling activities, such as engaging bed brakes and transporting patients in beds, which could render healthcare workers at risk of developing WMSDs. Effectiveness of hospital bed design features (brake pedal location and steering-assistance) was evaluated in terms of physical demands and usability during brake engagement and patient transportation tasks. Two laboratory-based studies were conducted. In simulated brake engagement tasks, three brake pedal locations (head-end vs. foot-end vs. side of a bed) and two hands conditions (hands-free vs. hands-occupied) were manipulated. Additionally, both in-room and corridor patient transportation tasks were simulated, in which activation of steering-assistance features (5th wheel and/or front wheel caster lock) and two patient masses were manipulated. Nine novice participants were recruited from the local student population and community for each study. During brake engagement, trunk flexion angle, task completion time, and questionnaires were used to quantify postural comfort and usability. For patient transportation, dependent measures were hand forces and questionnaire responses. Brake pedal locations and steering-assistance features in hospital beds had significant effects on physical demands and usability during brake engagement and patient transportation tasks. Specifically, a brake pedal at the head-end of a bed increased trunk flexion by 74-224% and completion time by 53-74%, compared to other pedal locations. Participants reported greater overall perceived difficulty and less postural comfort with the brake pedal at the head-end. During in-room transportation, participants generally reported "Neither Low nor High" physical demands

  13. Stabilization of the wheel running phenotype in mice.

    Science.gov (United States)

    Bowen, Robert S; Cates, Brittany E; Combs, Eric B; Dillard, Bryce M; Epting, Jessica T; Foster, Brittany R; Patterson, Shawnee V; Spivey, Thomas P

    2016-03-01

    Increased physical activity is well known to improve health and wellness by modifying the risks for many chronic diseases. Rodent wheel running behavior is a beneficial surrogate model to evaluate the biology of daily physical activity in humans. Upon initial exposure to a running wheel, individual mice differentially respond to the experience, which confounds the normal activity patterns exhibited in this otherwise repeatable phenotype. To promote phenotypic stability, a minimum seven-day (or greater) acclimation period is utilized. Although phenotypic stabilization is achieved during this 7-day period, data to support acclimation periods of this length are not currently available in the literature. The purpose of this project is to evaluate the wheel running response in C57BL/6j mice immediately following exposure to a running wheel. Twenty-eight male and thirty female C57BL/6j mice (Jackson Laboratory, Bar Harbor, ME) were acquired at eight weeks of age and were housed individually with free access to running wheels. Wheel running distance (km), duration (min), and speed (m∙min(-1)) were measured daily for fourteen days following initial housing. One-way ANOVAs were used to evaluate day-to-day differences in each wheel running character. Limits of agreement and mean difference statistics were calculated between days 1-13 (acclimating) and day 14 (acclimated) to assess day-to-day agreement between each parameter. Wheel running distance (males: F=5.653, p=2.14 × 10(-9); females: F=8.217, p=1.20 × 10(-14)), duration (males: F=2.613, p=0.001; females: F=4.529, p=3.28 × 10(-7)), and speed (males: F=7.803, p=1.22 × 10(-13); females: F=13.140, p=2.00 × 10(-16)) exhibited day-to-day differences. Tukey's HSD post-hoc testing indicated differences between early (males: days 1-3; females: days 1-6) and later (males: days >3; females: days >6) wheel running periods in distance and speed. Duration only exhibited an anomalous difference between wheel running on day 13

  14. Mechatronic track guidance on disturbed track: the trade-off between actuator performance and wheel wear

    Science.gov (United States)

    Kurzeck, Bernhard; Heckmann, Andreas; Wesseler, Christoph; Rapp, Matthias

    2014-05-01

    Future high-speed trains are the main focus of the DLR research project Next Generation Train. One central point of the research activities is the development of mechatronic track guidance for the two-axle intermediate wagons with steerable, individually powered, independently rotating wheels. The traction motors hereby fulfil two functions; they concurrently are traction drives and steering actuators. In this paper, the influence of the track properties - line layout and track irregularities - on the performance requirements for the guidance actuator is investigated using multi-body models in SIMPACK®. In order to compromise on the design conflict between low wheel wear and low steering torque, the control parameters of the mechatronic track guidance are optimised using the DLR in-house software MOPS. Besides the track irregularities especially the increasing inclination at transition curves defines high actuator requirements due to gyroscopic effects at high speed. After introducing a limiter for the actuating variables into the control system, a good performance is achieved.

  15. Wheeling rates evaluation using optimal power flows

    International Nuclear Information System (INIS)

    Muchayi, M.; El-Hawary, M. E.

    1998-01-01

    Wheeling is the transmission of electrical power and reactive power from a seller to a buyer through a transmission network owned by a third party. The wheeling rates are then the prices charged by the third party for the use of its network. This paper proposes and evaluates a strategy for pricing wheeling power using a pricing algorithm that in addition to the fuel cost for generation incorporates the optimal allocation of the transmission system operating cost, based on time-of-use pricing. The algorithm is implemented for the IEEE standard 14 and 30 bus system which involves solving a modified optimal power flow problem iteratively. The base of the proposed algorithm is the hourly spot price. The analysis spans a total time period of 24 hours. Unlike other algorithms that use DC models, the proposed model captures wheeling rates of both real and reactive power. Based on the evaluation, it was concluded that the model has the potential for wide application in calculating wheeling rates in a deregulated competitive power transmission environment. 9 refs., 3 tabs

  16. 49 CFR 229.75 - Wheels and tire defects.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Wheels and tire defects. 229.75 Section 229.75....75 Wheels and tire defects. Wheels and tires may not have any of the following conditions: (a) A... two adjoining spots that are each two or more inches in length. (e) A seam running lengthwise that is...

  17. Influence of Road Excitation and Steering Wheel Input on Vehicle System Dynamic Responses

    Directory of Open Access Journals (Sweden)

    Zhen-Feng Wang

    2017-06-01

    Full Text Available Considering the importance of increasing driving safety, the study of safety is a popular and critical topic of research in the vehicle industry. Vehicle roll behavior with sudden steering input is a main source of untripped rollover. However, previous research has seldom considered road excitation and its coupled effect on vehicle lateral response when focusing on lateral and vertical dynamics. To address this issue, a novel method was used to evaluate effects of varying road level and steering wheel input on vehicle roll behavior. Then, a 9 degree of freedom (9-DOF full-car roll nonlinear model including vertical and lateral dynamics was developed to study vehicle roll dynamics with or without of road excitation. Based on a 6-DOF half-car roll model and 9-DOF full-car nonlinear model, relationship between three-dimensional (3-D road excitation and various steering wheel inputs on vehicle roll performance was studied. Finally, an E-Class (SUV level car model in CARSIM® was used, as a benchmark, with and without road input conditions. Both half-car and full-car models were analyzed under steering wheel inputs of 5°, 10° and 15°. Simulation results showed that the half-car model considering road input was found to have a maximum accuracy of 65%. Whereas, the full-car model had a minimum accuracy of 85%, which was significantly higher compared to the half-car model under the same scenario.

  18. Wind-Sculpted Vicinity After Opportunity's Sol 1797 Drive (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 111 meters (364 feet) on the 1,797th Martian day, or sol, of Opportunity's surface mission (Feb. 12, 2009). North is at the center; south at both ends. Tracks from the drive recede northward across dark-toned sand ripples in the Meridiani Planum region of Mars. Patches of lighter-toned bedrock are visible on the left and right sides of the image. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). This view is presented as a polar projection with geometric seam correction.

  19. Wind-Sculpted Vicinity After Opportunity's Sol 1797 Drive (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 111 meters (364 feet) on the 1,797th Martian day, or sol, of Opportunity's surface mission (Feb. 12, 2009). North is at the center; south at both ends. Tracks from the drive recede northward across dark-toned sand ripples in the Meridiani Planum region of Mars. Patches of lighter-toned bedrock are visible on the left and right sides of the image. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). This view is presented as a vertical projection with geometric seam correction.

  20. To the question of modeling of wheels and rails wear processes

    Directory of Open Access Journals (Sweden)

    S.V. Myamlin

    2013-06-01

    Full Text Available Purpose. There is a need of wear process modeling in the wheel-rail system. This is related to the fact that the wear processes in this system are absolutely different in the initial and final stages. The profile change of rail and, especially, of the wheels caused by the wear significantly affects the rolling stock dynamics, traffic safety and the resource of the wheels and rails. Wear modeling and the traffic safety evaluation requires the accounting of the low frequency component forces (including the modeling of transitional areas affecting the wheel on the side of the rail and carriage in motion of rolling stock, so the statistical analysis is not possible. Methodology. The method of mathematical modeling of the wheel set and the rail interaction was used during the research conducting. Findings. As a result of the modeling of the wheel set motion on the rail track, the mathematic model with 19 freedom degrees was obtained. This model takes into account the axle torque and studies wheels constructions as the components of the mechanical systems, consisting of a hub and tire. Originality. The mathematic model allows evaluating the wear degree of the wheels and rails when using on the rolling stock not only all-metal wheel sets, but also compound ones with the use of spring wheels and independent rotation of semi-axes with the wheels. Practical value. The development of the improved mathematical model of freight car wheel set motion with differential rotation of the wheels and compound axles allows studying the wear processes of wheels and rails.

  1. A novel integrated chassis controller for full drive-by-wire vehicles

    Science.gov (United States)

    Song, Pan; Tomizuka, Masayoshi; Zong, Changfu

    2015-02-01

    In this paper, a systematic design with multiple hierarchical layers is adopted in the integrated chassis controller for full drive-by-wire vehicles. A reference model and the optimal preview acceleration driver model are utilised in the driver control layer to describe and realise the driver's anticipation of the vehicle's handling characteristics, respectively. Both the sliding mode control and terminal sliding mode control techniques are employed in the vehicle motion control (MC) layer to determine the MC efforts such that better tracking performance can be attained. In the tyre force allocation layer, a polygonal simplification method is proposed to deal with the constraints of the tyre adhesive limits efficiently and effectively, whereby the load transfer due to both roll and pitch is also taken into account which directly affects the constraints. By calculating the motor torque and steering angle of each wheel in the executive layer, the total workload of four wheels is minimised during normal driving, whereas the MC efforts are maximised in extreme handling conditions. The proposed controller is validated through simulation to improve vehicle stability and handling performance in both open- and closed-loop manoeuvres.

  2. The effect of wheel eccentricity and run-out on grinding forces, waviness, wheel wear and chatter

    OpenAIRE

    O'DONNELL, GARRET; MURPHY, STUART

    2011-01-01

    PUBLISHED The effect of grinding-wheel eccentricity on grinding forces, wheel wear and final waviness height was studied. Eccentricity was evident in force oscillations and acceleration and audio measurements. A model was developed to predict final scallop-profile shape from grinding parameters and eccentricity. Recommendations are given on detecting eccentricity and determining when eccentricity is tolerable.

  3. 29 CFR 1915.134 - Abrasive wheels.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Abrasive wheels. 1915.134 Section 1915.134 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... wheels shall fit freely on the spindle and shall not be forced on. The spindle nut shall be tightened...

  4. The influence of friction coefficient and wheel/rail profiles on energy dissipation in the wheel/rail contact

    NARCIS (Netherlands)

    Idarraga Alarcon, G.A.; Burgelman, N.D.M.; Meza Meza, J.; Toro, A.; Li, Z.

    2015-01-01

    This work investigates the energy dissipation in a wheel/rail system through friction work modeling. In order to identify the effect of the friction coefficient on the energy dissipation in the wheel/rail contact, several simulations were performed using a 3D multibody model of a railway vehicle

  5. Modeling of the motion of automobile elastic wheel in real-time for creation of wheeled vehicles motion control electronic systems

    Science.gov (United States)

    Balakina, E. V.; Zotov, N. M.; Fedin, A. P.

    2018-02-01

    Modeling of the motion of the elastic wheel of the vehicle in real-time is used in the tasks of constructing different models in the creation of wheeled vehicles motion control electronic systems, in the creation of automobile stand-simulators etc. The accuracy and the reliability of simulation of the parameters of the wheel motion in real-time when rolling with a slip within the given road conditions are determined not only by the choice of the model, but also by the inaccuracy and instability of the numerical calculation. It is established that the inaccuracy and instability of the calculation depend on the size of the step of integration and the numerical method being used. The analysis of these inaccuracy and instability when wheel rolling with a slip was made and recommendations for reducing them were developed. It is established that the total allowable range of steps of integration is 0.001.0.005 s; the strongest instability is manifested in the calculation of the angular and linear accelerations of the wheel; the weakest instability is manifested in the calculation of the translational velocity of the wheel and moving of the center of the wheel; the instability is less at large values of slip angle and on more slippery surfaces. A new method of the average acceleration is suggested, which allows to significantly reduce (up to 100%) the manifesting of instability of the solution in the calculation of all parameters of motion of the elastic wheel for different braking conditions and for the entire range of steps of integration. The results of research can be applied to the selection of control algorithms in vehicles motion control electronic systems and in the testing stand-simulators

  6. Control rod drive shaft latch

    International Nuclear Information System (INIS)

    Thorp, A.G. II.

    1976-01-01

    A latch mechanism is operated by differential pressure on a piston to engage the drive shaft for a control rod in a nuclear reactor, thereby preventing the control rod from being ejected from the reactor in case of failure of the control rod drive mechanism housing which is subjected to the internal pressure in the reactor vessel. 6 claims, 4 drawing figures

  7. Grinding Wheel Profile

    Science.gov (United States)

    2004-01-01

    This graphic dubbed by engineers as the 'Grinding Wheel Profile' is the detective's tool used by the Opportunity team to help them understand one of the processes that formed the interior of a rock called 'McKittrick.' Scientists are looking for clues as to how layers, grains and minerals helped create this rock, and the engineers who built the rock abrasion tool (RAT) wanted to ensure that their instrument's handiwork did not get confused with natural processes.In the original microscopic image underlaying the graphics, engineers and scientists noticed 'layers' or 'scratches' on the spherical object nicknamed 'blueberry' in the lower right part of the image. The designers of the rock abrasion tool noticed that the arc length and width of the scratches were similar to the shape and size of the rock abrasion tool's grinding wheel, which is made out of a pad of diamond teeth.The scrapes on the bottom right blueberry appear to be caused by the fact that the berry got dislodged slightly and its surface was scraped with the grinding pad. In this image, the largest yellow circle is the overall diameter of the hole ground by the rock abrasion tool and the largest yellow rectangular shape is the area of the grinding wheel bit. The smaller yellow semi-circle is the path that the center of the grinding tool follows. The orange arrow arcing around the solid yellow circle (center of grinding tool) indicates the direction that the grinding tool spins around its own center at 3,000 revolutions per minute. The tool simultaneously spins in an orbit around the center of the hole, indicated by the larger orange arrow to the left.The grinding tool is 22 millimeters (0.9 inches) in length and the actual grinding surface, which consists of the diamond pad, is 1.5 millimeters (0.06 inches) in length, indicated by the two smaller rectangles. You can see that the smaller bottom rectangle fits exactly the width of the scrape marks.The grooves on the blueberry are also the same as the

  8. The colour wheels of art, perception, science and physiology

    Science.gov (United States)

    Harkness, Nick

    2006-06-01

    Colour is not the domain of any one discipline be it art, philosophy, psychology or science. Each discipline has its own colour wheel and this presentation examines the origins and philosophies behind the colour circles of Art, Perception, Science and Physiology (after image) with reference to Aristotle, Robert Boyle, Leonardo da Vinci, Goethe, Ewald Hering and Albert Munsell. The paper analyses and discusses the differences between the four colour wheels using the Natural Colour System® notation as the reference for hue (the position of colours within each of the colour wheels). Examination of the colour wheels shows the dominance of blue in the wheels of art, science and physiology particularly at the expense of green. This paper does not consider the three-dimensionality of colour space its goal was to review the hue of a colour with regard to its position on the respective colour wheels.

  9. Evolutionary algorithm for vehicle driving cycle generation.

    Science.gov (United States)

    Perhinschi, Mario G; Marlowe, Christopher; Tamayo, Sergio; Tu, Jun; Wayne, W Scott

    2011-09-01

    Modeling transit bus emissions and fuel economy requires a large amount of experimental data over wide ranges of operational conditions. Chassis dynamometer tests are typically performed using representative driving cycles defined based on vehicle instantaneous speed as sequences of "microtrips", which are intervals between consecutive vehicle stops. Overall significant parameters of the driving cycle, such as average speed, stops per mile, kinetic intensity, and others, are used as independent variables in the modeling process. Performing tests at all the necessary combinations of parameters is expensive and time consuming. In this paper, a methodology is proposed for building driving cycles at prescribed independent variable values using experimental data through the concatenation of "microtrips" isolated from a limited number of standard chassis dynamometer test cycles. The selection of the adequate "microtrips" is achieved through a customized evolutionary algorithm. The genetic representation uses microtrip definitions as genes. Specific mutation, crossover, and karyotype alteration operators have been defined. The Roulette-Wheel selection technique with elitist strategy drives the optimization process, which consists of minimizing the errors to desired overall cycle parameters. This utility is part of the Integrated Bus Information System developed at West Virginia University.

  10. Wheeled mobility device transportation safety in fixed route and demand-responsive public transit vehicles within the United States.

    Science.gov (United States)

    Frost, Karen L; van Roosmalen, Linda; Bertocci, Gina; Cross, Douglas J

    2012-01-01

    An overview of the current status of wheelchair transportation safety in fixed route and demand-responsive, non-rail, public transportation vehicles within the US is presented. A description of each mode of transportation is provided, followed by a discussion of the primary issues affecting safety, accessibility, and usability. Technologies such as lifts, ramps, securement systems, and occupant restraint systems, along with regulations and voluntary industry standards have been implemented with the intent of improving safety and accessibility for individuals who travel while seated in their wheeled mobility device (e.g., wheelchair or scooter). However, across both fixed route and demand-responsive transit systems a myriad of factors such as nonuse and misuse of safety systems, oversized wheeled mobility devices, vehicle space constraints, and inadequate vehicle operator training may place wheeled mobility device (WhMD) users at risk of injury even under non-impact driving conditions. Since WhMD-related incidents also often occur during the boarding and alighting process, the frequency of these events, along with factors associated with these events are described for each transit mode. Recommendations for improving WhMD transportation are discussed given the current state of

  11. Wheel running, voluntary ethanol consumption, and hedonic substitution.

    Science.gov (United States)

    Ozburn, Angela Renee; Harris, R Adron; Blednov, Yuri A

    2008-08-01

    Few studies have examined the relationship between naturally rewarding behaviors and ethanol drinking behaviors in mice. Although natural and drug reinforcers activate similar brain circuitry, there is behavioral evidence suggesting food and drug rewards differ in perceived value. The primary goal of the present study was to investigate the relationships between naturally reinforcing stimuli and consumption of ethanol in ethanol preferring C57BL/6J mice. Mouse behaviors were observed after the following environmental manipulations: standard or enhanced environment, accessible or inaccessible wheel, and presence or absence of ethanol. Using a high-resolution volumetric drinking monitor and wheel running monitor, we evaluated whether alternating access to wheel running modified ethanol-related behaviors and whether alternating access to ethanol modified wheel running or subsequent ethanol-related behaviors. We found that ethanol consumption remains stable with alternating periods of wheel running. Wheel running increases in the absence of ethanol and decreases upon reintroduction of ethanol. Upon reintroduction of ethanol, an alcohol deprivation effect was seen. Collectively, the results support theories of hedonic substitution and suggest that female C57BL/6J mice express ethanol seeking and craving under these specific conditions.

  12. Study on the Attitude Control of Spacecraft Using Reaction Wheels

    Directory of Open Access Journals (Sweden)

    Ju-Young Du

    1998-06-01

    Full Text Available Attitude determination and control of satellite is important component which determines the accomplish satellite missions. In this study, attitude control using reaction wheels and momentum dumping of wheels are considered. Attitude control law is designed by Sliding control and LQR. Attitude maneuver control law is obtained by Shooting method. Wheels momentum dumping control law is designed by Bang-Bang control. Four reaction wheels are configurated for minimized the electric power consumption. Wheels control torque and magnetic moment of magnetic torquer are limited.

  13. Estimating Driving Performance Based on EEG Spectrum Analysis

    Directory of Open Access Journals (Sweden)

    Jung Tzyy-Ping

    2005-01-01

    Full Text Available The growing number of traffic accidents in recent years has become a serious concern to society. Accidents caused by driver's drowsiness behind the steering wheel have a high fatality rate because of the marked decline in the driver's abilities of perception, recognition, and vehicle control abilities while sleepy. Preventing such accidents caused by drowsiness is highly desirable but requires techniques for continuously detecting, estimating, and predicting the level of alertness of drivers and delivering effective feedbacks to maintain their maximum performance. This paper proposes an EEG-based drowsiness estimation system that combines electroencephalogram (EEG log subband power spectrum, correlation analysis, principal component analysis, and linear regression models to indirectly estimate driver's drowsiness level in a virtual-reality-based driving simulator. Our results demonstrated that it is feasible to accurately estimate quantitatively driving performance, expressed as deviation between the center of the vehicle and the center of the cruising lane, in a realistic driving simulator.

  14. Benefits of magnesium wheels for consumer cars

    Science.gov (United States)

    Frishfelds, Vilnis; Timuhins, Andrejs; Bethers, Uldis

    2018-05-01

    Advantages and disadvantages of magnesium wheels are considered based on a mechanical model of a car. Magnesium wheels are usually applied to racing cars as they provide slightly better strength/weight ratio than aluminum alloys. Do they provide notable benefits also for the everyday user when the car speeds do not exceed allowed speed limit? Distinct properties of magnesium rims are discussed. Apart from lighter weight of magnesium alloys, they are also good in dissipating the energy of vibrations. The role of energy dissipation in the rim of a wheel is estimated by a quarter car model. Improvements to safety by using the magnesium wheels are considered. Braking distance and responsiveness of the car is studied both with and without using an Anti Blocking System (ABS). Influence of rim weight on various handling parameters of the car is quantitatively tested.

  15. The Fatigue Life Prediction of Train Wheel Rims Containing Spherical Inclusions

    Science.gov (United States)

    Li, Yajie; Chen, Huanguo; Cai, Li; Chen, Pei; Qian, Jiacheng; Wu, Jianwei

    2018-03-01

    It is a common phenomenon that fatigue crack initiation occurs frequently in the inclusions of wheel rims. Research on the fatigue life of wheel rims with spherical inclusions is of great significance on the reliability of wheels. To find the danger point and working condition of a wheel, the stress state of the wheel rim with spherical inclusions was analyzed using the finite element method. Results revealed that curve conditions are dangerous. The critical plane method, based on the cumulative fatigue damage theory, was used to predict the fatigue life of the wheel rim and whether it contained spherical inclusions or not under curve conditions. It was found that the fatigue life of the wheel rim is significantly shorter when the wheel rim contains spherical inclusions. Analysis of the results can provide a theoretical basis and technical support for train operations and maintenance.

  16. Further study on the wheel-rail impact response induced by a single wheel flat: the coupling effect of strain rate and thermal stress

    Science.gov (United States)

    Jing, Lin; Han, Liangliang

    2017-12-01

    A comprehensive dynamic finite-element simulation method was proposed to study the wheel-rail impact response induced by a single wheel flat based on a 3-D rolling contact model, where the influences of the structural inertia, strain rate effect of wheel-rail materials and thermal stress due to the wheel-rail sliding friction were considered. Four different initial conditions (i.e. pure mechanical loading plus rate-independent, pure mechanical loading plus rate-dependent, thermo-mechanical loading plus rate-independent, and thermo-mechanical loading plus rate-dependent) were involved into explore the corresponding impact responses in term of the vertical impact force, von-Mises equivalent stress, equivalent plastic strain and shear stress. Influences of train speed, flat length and axle load on the flat-induced wheel-rail impact response were discussed, respectively. The results indicate that the maximum thermal stresses are occurred on the tread of the wheel and on the top surface of the middle rail; the strain rate hardening effect contributes to elevate the von-Mises equivalent stress and restrain the plastic deformation; and the initial thermal stress due to the sliding friction will aggravate the plastic deformation of wheel and rail. Besides, the wheel-rail impact responses (i.e. impact force, von-Mises equivalent stress, equivalent plastic strain, and XY shear stress) induced by a flat are sensitive to the train speed, flat length and axle load.

  17. Low-cost real-time automatic wheel classification system

    Science.gov (United States)

    Shabestari, Behrouz N.; Miller, John W. V.; Wedding, Victoria

    1992-11-01

    This paper describes the design and implementation of a low-cost machine vision system for identifying various types of automotive wheels which are manufactured in several styles and sizes. In this application, a variety of wheels travel on a conveyor in random order through a number of processing steps. One of these processes requires the identification of the wheel type which was performed manually by an operator. A vision system was designed to provide the required identification. The system consisted of an annular illumination source, a CCD TV camera, frame grabber, and 386-compatible computer. Statistical pattern recognition techniques were used to provide robust classification as well as a simple means for adding new wheel designs to the system. Maintenance of the system can be performed by plant personnel with minimal training. The basic steps for identification include image acquisition, segmentation of the regions of interest, extraction of selected features, and classification. The vision system has been installed in a plant and has proven to be extremely effective. The system properly identifies the wheels correctly up to 30 wheels per minute regardless of rotational orientation in the camera's field of view. Correct classification can even be achieved if a portion of the wheel is blocked off from the camera. Significant cost savings have been achieved by a reduction in scrap associated with incorrect manual classification as well as a reduction of labor in a tedious task.

  18. OPTIMIZATION OF HEATING OF GEAR WHEEL USING NUMERICAL MODELING

    Directory of Open Access Journals (Sweden)

    Soňa Benešová

    2013-09-01

    Full Text Available Successful heat treating and carburizing of gear wheels for wind turbine gear boxes requires that plastic deformation in the wheel is minimized. Numerical modeling using the DEFORM software was aimed at exploring the effects of the base, on which the gear wheel rests during heating, on the heating process. Homogeneous heating was assumed. It was found that the base heats up more quickly than the workpiece. It is the consequence of the base's shape and volume. As a result, the base expands and slides against the wheel, predominantly at the first heating stage. Later on, it prevents the gear wheel from expanding, causing plastic deformation in the wheel. The findings were used for designing new heating schedules to minimize these undesirable interactions and to reduce the plastic deformation to a negligible magnitude. In addition, this paper presents an example of a practical use of numerical modeling in the DEFORM software.

  19. OPTIMIZATION OF HEATING OF GEAR WHEEL USING NUMERICAL MODELING

    Directory of Open Access Journals (Sweden)

    Sona Benesova

    2013-05-01

    Full Text Available Successful heat treating and carburizing of gear wheels for wind turbine gear boxes requires that plastic deformation in the wheel is minimized. Numerical modeling using the DEFORM software was aimed at exploring the effects of the base, on which the gear wheel rests during heating, on the heating process. Homogeneous heating was assumed. It was found that the base heats up more quickly than the workpiece. It is the consequence of the base's shape and volume. As a result, the base expands and slides against the wheel, predominantly at the first heating stage. Later on, it prevents the gear wheel from expanding, causing plastic deformation in the wheel. The findings were used for designing new heating schedules to minimize these undesirable interactions and to reduce the plastic deformation to a negligible magnitude. In addition, this paper presents an example of a practical use of numerical modeling in the DEFORM software.

  20. Arrangement for adapting a wind wheel to an electric power generator

    Energy Technology Data Exchange (ETDEWEB)

    Beusse, H

    1977-08-11

    The invention is concerned with a device for adapting a wind wheel to an electric power generator in such a way that the wind wheel will always be operated with a maximum performance coefficient, that another source of energy, e.g. a prime mover, can supply the power deficit if the wind power is not sufficient, and that the generator at the output of the facility is kept mains-synchronous of constant speed and constant voltage. According to the invention, the shaft power of the wind power engine is transmitted to a first generator driving an electromotor. The motor is coupled to a second generator feeding into a consumer grid. By means of an anemometer the excitation output of the motor is controled in such manner that the speed of the generator is practically constant-provided a sufficient supply of wind is available. On the shaft of the output generator a prinse mover, e.g. a Diesel engine, is mounted being controllable for contant speed by means of a controll device in such a way that the prime mover takes over the missing amount of power if the wind supply falls short of the power taken off at the generator output.

  1. Mice from lines selectively bred for high voluntary wheel running exhibit lower blood pressure during withdrawal from wheel access.

    Science.gov (United States)

    Kolb, Erik M; Kelly, Scott A; Garland, Theodore

    2013-03-15

    Exercise is known to be rewarding and have positive effects on mental and physical health. Excessive exercise, however, can be the result of an underlying behavioral/physiological addiction. Both humans who exercise regularly and rodent models of exercise addiction sometimes display behavioral withdrawal symptoms, including depression and anxiety, when exercise is denied. However, few studies have examined the physiological state that occurs during this withdrawal period. Alterations in blood pressure (BP) are common physiological indicators of withdrawal in a variety of addictions. In this study, we examined exercise withdrawal in four replicate lines of mice selectively bred for high voluntary wheel running (HR lines). Mice from the HR lines run almost 3-fold greater distances on wheels than those from non-selected control lines, and have altered brain activity as well as increased behavioral despair when wheel access is removed. We tested the hypothesis that male HR mice have an altered cardiovascular response (heart rate, systolic, diastolic, and mean arterial pressure [MAP]) during exercise withdrawal. Measurements using an occlusion tail-cuff system were taken during 8 days of baseline, 6 days of wheel access, and 2 days of withdrawal (wheel access blocked). During withdrawal, HR mice had significantly lower systolic BP, diastolic BP, and MAP than controls, potentially indicating a differential dependence on voluntary wheel running in HR mice. This is the first characterization of a cardiovascular withdrawal response in an animal model of high voluntary exercise. Copyright © 2013. Published by Elsevier Inc.

  2. Analysis of wheel rim - Material and manufacturing aspects

    Science.gov (United States)

    Misra, Sheelam; Singh, Abhiraaj; James, Eldhose

    2018-05-01

    The tire in an automobile is supported by the rim of the wheel and its shape and dimensions should be adjusted to accommodate a specified tire. In this study, a tire of car wheel rim belonging to the disc wheel category is considered. Design is an important industrial operation used to define and specify the quality of the product. The design and modelling reduces the risk of damage involved in the manufacturing process. The design performed on this wheel rim is done on modelling software. After designing the model, it is imported for analysis purposes. The analysis software is used to calculate the different types of force, stresses, torque, and pressures acting upon the rim of the wheel and it reduces the time spent by a human for mathematical calculations. The analysis carried out considers two different materials namely structural steel and aluminium. Both materials are analyzed and their performance is noted.

  3. Blocking of conditioned taste avoidance induced by wheel running.

    Science.gov (United States)

    Pierce, W David; Heth, C Donald

    2010-01-01

    In Experiment 1, compared to non-reinforced presentation of a food stimulus (A-->no US), the association of a food stimulus with wheel running (A-->US) blocked subsequent avoidance of a distinctive flavor (X), when both the food and flavor were followed by wheel running (AX-->US). Experiment 2 replicated and extended the blocking effect, demonstrating that the amount of avoidance of X after AX-->wheel training depended on the correlation between A-alone trials and wheel running-the predictiveness of the A stimulus. The present study is the first to demonstrate associative blocking of conditioned taste avoidance (CTA) induced by wheel running and strongly implicates associative learning as the basis for this kind of avoidance. 2009 Elsevier B.V. All rights reserved.

  4. The Running Wheel Enhances Food Anticipatory Activity: An Exploratory Study.

    Science.gov (United States)

    Flôres, Danilo E F L; Bettilyon, Crystal N; Jia, Lori; Yamazaki, Shin

    2016-01-01

    Rodents anticipate rewarding stimuli such as daily meals, mates, and stimulant drugs. When a single meal is provided daily at a fixed time of day, an increase in activity, known as food anticipatory activity (FAA), occurs several hours before feeding time. The factors affecting the expression of FAA have not been well-studied. Understanding these factors may provide clues to the undiscovered anatomical substrates of food entrainment. In this study we determined whether wheel-running activity, which is also rewarding to rodents, modulated the robustness of FAA. We found that access to a freely rotating wheel enhanced the robustness of FAA. This enhancement was lost when the wheel was removed. In addition, while prior exposure to a running wheel alone did not enhance FAA, the presence of a locked wheel did enhance FAA as long as mice had previously run in the wheel. Together, these data suggest that FAA, like wheel-running activity, is influenced by reward signaling.

  5. Do as I say, not as I do: Distracted driving behavior of teens and their parents.

    Science.gov (United States)

    Raymond Bingham, C; Zakrajsek, Jennifer S; Almani, Farideh; Shope, Jean T; Sayer, Tina B

    2015-12-01

    Driver distraction is an important contributor to crash risk. Teenage driver distraction can be influenced by the attitudes and behaviors of parents. This study examined teens' and their parents' engagement in distracting behavior while driving. Survey data were collected from a national sample of 403 parent-teen dyads using random-digit dialing telephone interviews. Results demonstrated few parent or teen sex differences in distracting behavior engagement while driving, or in their perceptions of each others' behavior. Parents and teens' frequencies of distracting behavior engagement were positively correlated. Parents' and teens' perceptions of each others' distracting behavior engagement while driving exceeded their own selfreports. Finally, the likelihood that teens reported engaging in distracting behavior while driving was more strongly associated with their perceptions of their parents' distracting behavior than by parents' self reports of their own behavior. These results suggest that parents' examples of driving behavior are an important influence on teen driving behavior, but potentially more important are teens' perceptions of their parents' behaviors. Published by Elsevier Ltd.

  6. Real-Time Human in the Loop MBS Simulation in the Fraunhofer Robot-Based Driving Simulator

    Directory of Open Access Journals (Sweden)

    Kleer Michael

    2014-08-01

    Full Text Available The paper encompasses the overview of hardware architecture and the systems characteristics of the Fraunhofer driving simulator. First, the requirements of the real-time model and the real-time calculation hardware are defined and discussed in detail. Aspects like transport delay and the parallel computation of complex real-time models are presented. In addition, the interfacing of the models with the simulator system is shown. Two simulator driving tests, including a fully interactive rough terrain driving with a wheeled excavator and a test drive with a passenger car, are set to demonstrate system characteristics. Furthermore, the simulator characteristics of practical significance, such as simulator response time delay, simulator acceleration signal bandwidth obtained from artificial excitation and from the simulator driving test, will be presented and discussed.

  7. Development and application of resilient wheels in urban rail transit vehicle

    Directory of Open Access Journals (Sweden)

    Juan WEN

    Full Text Available Urban rail transit vehicles have been more and more attractive to people as a kind of fast, comfortable, energy-saving, environmental protection and safe transportation. But because of the vehicle noise and vibration, urban rail vehicles also face severe challenges. The research of resilient wheels has been continuously developed and improved. Based on the review of development background and structure sorts of resilient wheels, the advantages of resilient wheels are described, and the research status of noise and vibration reducing, infinite element strength analysis, vehicle dynamic analysis and the wheel-rail wear of resilient wheels are discussed. Taking the low-floor LRVs (light rail vehicles in domestic and overseas as example, the development and application of the resilient wheels in city rail transit is described, and the application prospects of the resilient wheels in LRVs in domestic and the future research direction of elastic wheel are discussed.

  8. Wheel-running reinforcement in free-feeding and food-deprived rats.

    Science.gov (United States)

    Belke, Terry W; Pierce, W David

    2016-03-01

    Rats experiencing sessions of 30min free access to wheel running were assigned to ad-lib and food-deprived groups, and given additional sessions of free wheel activity. Subsequently, both ad-lib and deprived rats lever pressed for 60s of wheel running on fixed ratio (FR) 1, variable ratio (VR) 3, VR 5, and VR 10 schedules, and on a response-initiated variable interval (VI) 30s schedule. Finally, the ad-lib rats were switched to food deprivation and the food-deprived rats were switched to free food, as rats continued responding on the response-initiated VI 30-s schedule. Wheel running functioned as reinforcement for both ad-lib and food-deprived rats. Food-deprived rats, however, ran faster and had higher overall lever-pressing rates than free-feeding rats. On the VR schedules, wheel-running rates positively correlated with local and overall lever pressing rates for deprived, but not ad-lib rats. On the response-initiated VI 30s schedule, wheel-running rates and lever-pressing rates changed for ad-lib rats switched to food deprivation, but not for food-deprived rats switched to free-feeding. The overall pattern of results suggested different sources of control for wheel running: intrinsic motivation, contingencies of automatic reinforcement, and food-restricted wheel running. An implication is that generalizations about operant responding for wheel running in food-deprived rats may not extend to wheel running and operant responding of free-feeding animals. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Safe Driving in Illinois. A Manual to Accompany the Illinois Rules of the Road.

    Science.gov (United States)

    Rice, Gail; Nowack, Linda

    Designed to accompany and supplement the Illinois Rules of the Road manual, this book is intended to better prepare future drivers for the written test for the instruction permit or driver's license. It includes many pictures and shows and describes driving situations a driver will probably face when behind the wheel. Parts dealing with important…

  10. Kalman Filter Sensor Fusion for Mecanum Wheeled Automated Guided Vehicle Localization

    Directory of Open Access Journals (Sweden)

    Sang Won Yoon

    2015-01-01

    Full Text Available The Mecanum automated guided vehicle (AGV, which can move in any direction by using a special wheel structure with a LIM-wheel and a diagonally positioned roller, holds considerable promise for the field of industrial electronics. A conventional method for Mecanum AGV localization has certain limitations, such as slip phenomena, because there are variations in the surface of the road and ground friction. Therefore, precise localization is a very important issue for the inevitable slip phenomenon situation. So a sensor fusion technique is developed to cope with this drawback by using the Kalman filter. ENCODER and StarGazer were used for sensor fusion. StarGazer is a position sensor for an image recognition device and always generates some errors due to the limitations of the image recognition device. ENCODER has also errors accumulating over time. On the other hand, there are no moving errors. In this study, we developed a Mecanum AGV prototype system and showed by simulation that we can eliminate the disadvantages of each sensor. We obtained the precise localization of the Mecanum AGV in a slip phenomenon situation via sensor fusion using a Kalman filter.

  11. Dynamic and Acoustic Characterisation of Automotive Wheels

    Directory of Open Access Journals (Sweden)

    Francesca Curà

    2004-01-01

    Full Text Available The subject of this paper is the dynamic and acoustic characterisation of an automotive wheel. In particular, an experimental research activity previously performed by the authors about the dynamic behaviour of automotive wheels has been extended to the acoustic field.

  12. Reinventing the Wheel: The Economic Benefits of Wheeled Transportation in Early British Colonial West Africa

    OpenAIRE

    Isaías N. Chaves; Stanley L. Engerman; James A. Robinson

    2013-01-01

    One of the great puzzles of Sub-Saharan African economic history is that wheeled transportation was barely used prior to the colonial period. Instead, head porterage was the main method of transportation. The consensus among historians is that this was a rational adaption to the underlying conditions and factor endowments. In this paper we undertake the first systematic investigation of the relative costs of the different forms of wheeled transportation in Africa. We focus on calculating the ...

  13. Kinematics and dynamics modelling of a mecanum wheeled mobile platform

    CSIR Research Space (South Africa)

    Tlale, NS

    2008-12-01

    Full Text Available analysis for mecanum wheeled mobile platform same time during the operation of the mobile platform, a maximum of eighty-one combinations of wheels (four wheels: 1,2, 3 and 4) and directions of rotational velocity of wheels (three directions of rotation... = I ’ (15) where ai is a constant depending on the wheel number and ai = -1 for i = 1 and 4, and ai = 1 for i = 2 and 3, T is the torque developed on the vehicle that changes the posture of the vehicle, I is the mass inertia of the vehicle...

  14. Pre-exposure to wheel running disrupts taste aversion conditioning.

    Science.gov (United States)

    Salvy, Sarah-Jeanne; Pierce, W David; Heth, Donald C; Russell, James C

    2002-05-01

    When rats are given access to a running wheel after drinking a flavored solution, they subsequently drink less of that flavor solution. It has been suggested that running produces a conditioned taste aversion (CTA). This study explored whether CTA is eliminated by prior exposure to wheel running [i.e., unconditioned stimulus (UCS) pre-exposure effect]. The rats in the experimental group (UW) were allowed to wheel run for 1 h daily for seven consecutive days of pre-exposure. Rats in the two other groups had either access to locked wheels (LW group) or were maintained in their home cages (HC group) during the pre-exposure days. All rats were then exposed to four paired and four unpaired trials using a "ABBAABBA" design. Conditioning trials were composed of one flavored liquid followed by 60-min access to wheel running. For the unpaired trials, rats received a different flavor not followed by the opportunity to run. All rats were then initially tested for water consumption followed by tests of the two flavors (paired or unpaired) in a counterbalanced design. Rats in the UW group show no CTA to the liquid paired with wheel running, whereas LW and HC groups developed CTA. These results indicate that pre-exposure to wheel running (i.e., the UCS), eliminates subsequent CTA.

  15. Tensegrital Wheel for Enhanced Surface Mobility, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations introduces the "tensegrital wheel" an inventive concept for wheeled locomotion that exploits the geometric and mechanical attributes of a tensegrity...

  16. A Nontoxic Barlow's Wheel

    Science.gov (United States)

    Daffron, John A.; Greenslade, Thomas B., Jr.

    2015-01-01

    Barlow's wheel has been a favorite demonstration since its invention by Peter Barlow (1776-1862) in 1822. In the form shown in Fig. 1, it represents the first electric motor. The interaction between the electric current passing from the axle of the wheel to the rim and the magnetic field produced by the U-magnet produces a torque that turns…

  17. Universal Drive Train Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This vehicle drive train research facility is capable of evaluating helicopter and ground vehicle power transmission technologies in a system level environment. The...

  18. Reaction Wheel Disturbance Model Extraction Software, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Reaction wheel disturbances are some of the largest sources of noise on sensitive telescopes. Such wheel-induced mechanical noises are not well characterized....

  19. A Full Disturbance Model for Reaction Wheels

    NARCIS (Netherlands)

    Le, M.P.; Ellenbroek, Marcellinus Hermannus Maria; Seiler, R; van Put, P.; Cottaar, E.J.E.

    2014-01-01

    Reaction wheels are rotating devices used for the attitude control of spacecraft. However, reaction wheels also generate undesired disturbances in the form of vibrations, which may have an adverse effect on the pointing accuracy and stability of spacecraft (optical) payloads. A disturbance model for

  20. Western diet increases wheel running in mice selectively bred for high voluntary wheel running.

    Science.gov (United States)

    Meek, T H; Eisenmann, J C; Garland, T

    2010-06-01

    Mice from a long-term selective breeding experiment for high voluntary wheel running offer a unique model to examine the contributions of genetic and environmental factors in determining the aspects of behavior and metabolism relevant to body-weight regulation and obesity. Starting with generation 16 and continuing through to generation 52, mice from the four replicate high runner (HR) lines have run 2.5-3-fold more revolutions per day as compared with four non-selected control (C) lines, but the nature of this apparent selection limit is not understood. We hypothesized that it might involve the availability of dietary lipids. Wheel running, food consumption (Teklad Rodent Diet (W) 8604, 14% kJ from fat; or Harlan Teklad TD.88137 Western Diet (WD), 42% kJ from fat) and body mass were measured over 1-2-week intervals in 100 males for 2 months starting 3 days after weaning. WD was obesogenic for both HR and C, significantly increasing both body mass and retroperitoneal fat pad mass, the latter even when controlling statistically for wheel-running distance and caloric intake. The HR mice had significantly less fat than C mice, explainable statistically by their greater running distance. On adjusting for body mass, HR mice showed higher caloric intake than C mice, also explainable by their higher running. Accounting for body mass and running, WD initially caused increased caloric intake in both HR and C, but this effect was reversed during the last four weeks of the study. Western diet had little or no effect on wheel running in C mice, but increased revolutions per day by as much as 75% in HR mice, mainly through increased time spent running. The remarkable stimulation of wheel running by WD in HR mice may involve fuel usage during prolonged endurance exercise and/or direct behavioral effects on motivation. Their unique behavioral responses to WD may render HR mice an important model for understanding the control of voluntary activity levels.

  1. A rotating target wheel system for gammasphere

    International Nuclear Information System (INIS)

    Greene, J. P.

    1999-01-01

    A description is given for a low-mass, rotating target wheel to be used within the Gammasphere target chamber. This system was developed for experiments employing high beam currents in order to extend lifetimes of targets using low-melting point target material. The design is based on a previously successful implementation of rotating target wheels for the Argonne Positron Experiment (APEX) as well as the Fragment Mass Analyser (FMA) at ATLAS (Argonne Tandem Linac Accelerator System). A brief history of these rotating target wheel systems is given as well as a discussion on target preparation and performance

  2. Two new wheels for ATLAS

    CERN Multimedia

    2002-01-01

    Juergen Zimmer (Max Planck Institute), Roy Langstaff (TRIUMF/Victoria) and Sergej Kakurin (JINR), in front of one of the completed wheels of the ATLAS Hadronic End Cap Calorimeter. A decade of careful preparation and construction by groups in three continents is nearing completion with the assembly of two of the four 4 m diameter wheels required for the ATLAS Hadronic End Cap Calorimeter. The first two wheels have successfully passed all their mechanical and electrical tests, and have been rotated on schedule into the vertical position required in the experiment. 'This is an important milestone in the completion of the ATLAS End Cap Calorimetry' explains Chris Oram, who heads the Hadronic End Cap Calorimeter group. Like most experiments at particle colliders, ATLAS consists of several layers of detectors in the form of a 'barrel' and two 'end caps'. The Hadronic Calorimeter layer, which measures the energies of particles such as protons and pions, uses two techniques. The barrel part (Tile Calorimeter) cons...

  3. Wheelchair users' perceptions of and experiences with power assist wheels.

    Science.gov (United States)

    Giacobbi, Peter R; Levy, Charles E; Dietrich, Frederick D; Winkler, Sandra Hubbard; Tillman, Mark D; Chow, John W

    2010-03-01

    To assess wheelchair users' perceptions of and experiences with power assist wheels using qualitative interview methods. Qualitative evaluations were conducted in a laboratory setting with a focus on users' experiences using power assist wheel in their naturalistic environments. Participants consisted of seven women and 13 men (M(age) = 42.75, SD = 14.68) that included one African American, one Hispanic, 17 whites, and one individual from Zambia. Qualitative interviews were conducted before, during, and after use of a power assist wheel. Main outcome measures included the wheelchair users' evaluations and experiences related to the use of power assist wheels. The primary evaluations included wheeling on challenging terrains, performance of novel activities, social/family aspects, fatigue, and pain. These descriptions indicated that most participants perceived positive experiences with the power assist wheels, including access to new and different activities. Secondary evaluations indicated that the unit was cumbersome and prohibitive for some participants because of difficulties with transport in and out of a vehicle and battery life. Most participants felt that power assist wheels provided more independence and social opportunities. The power assist wheel seems to offer physical and social benefits for most wheelers. Clinicians should consider users' home environment and overall life circumstances before prescribing.

  4. Resting Is Rusting: A Critical View on Rodent Wheel-Running Behavior.

    Science.gov (United States)

    Richter, Sophie Helene; Gass, Peter; Fuss, Johannes

    2014-08-01

    Physical exercise is known to exert various beneficial effects on brain function and bodily health throughout life. In biomedical research, these effects are widely studied by introducing running wheels into the cages of laboratory rodents. Yet, although rodents start to run in the wheels immediately, and perform wheel-running excessively on a voluntary basis, the biological significance of wheel-running is still not clear. Here, we review the current literature on wheel-running and discuss potentially negative side-effects that may give cause for concern. We particularly emphasize on analogies of wheel-running with stereotypic and addictive behavior to stimulate further research on this topic. © The Author(s) 2014.

  5. Student motorcyclists' mobile phone use while driving in Vientiane, Laos.

    Science.gov (United States)

    Phommachanh, Sysavanh; Ichikawa, Masao; Nakahara, Shinji; Mayxay, Mayfong; Kimura, Akio

    2017-06-01

    To investigate mobile phone use while driving among student motorcyclists in Laos, we conducted a school-based questionnaire survey in central Vientiane in May 2014. Of the 883 high school students who reported to drive motorcycles at least once a week, 40% have ever used phones while driving motorcycles in both sexes. Those phone users had longer driving exposures than non-users, with about half engaging in phone use while driving at least 2 days a week and 70% engaging for 1 min or longer on an average day. They reported not just talking on the phone while driving but operating the phone such as dialling and text-messaging. In some instances, phone use was reportedly involved in their past crash experiences. To formulate a sound policy on this emerging distracting behaviour among motorcyclists, its contribution to the occurrence of overall crashes among motorcyclists should be investigated.

  6. Latent effectiveness of desiccant wheel: A silica gels- water system

    International Nuclear Information System (INIS)

    Rabah, A. A.; Mohamed, S. A.

    2009-01-01

    A latent heat effectiveness model in term of dimensionless groups? =f (NTU, m * ,Crm * ) for energy wheel has been analytically derived. The energy wheel is divided into humidification and dehumidification sections. For each section macroscopic mass differential equations for gas and the matrix were applied. In this process local latent effectiveness (? c ,? h ) for the humidification and dehumidification section of the wheel were obtained. The Latent effectiveness of the wheel is then derived form local effectiveness [? =f (? c ,? h)]. The model is compared with the existing experimental investigation and manufacturer data for energy wheel. More than 90% of the experimental data within a confidence limit of 95%. (Author)

  7. Predicting the wheel rolling resistance regarding important motion parameters using the artificial neural network

    Directory of Open Access Journals (Sweden)

    F Gheshlaghi

    2016-04-01

    Full Text Available Introduction: Rolling resistance is one of the most substantial energy losses when the wheel moves on soft soil. Rolling resistance value optimization will help to improve energy efficiency. Accurate modeling of the interaction soil-tire is an important key to this optimization and has eliminated the need for costly field tests and has reduced the time required to test. Rolling resistance will change because of the tire and wheel motion parameters and characteristics of the ground surface. Some tire design parameters are more important such as the tire diameter, width, tire aspect ratio, lugs form, inflation pressure and mechanical properties of tire structure. On the other hand, the soil or ground surface characteristics include soil type; moisture content and bulk density have an important role in this phenomenon. In addition, the vertical load and the wheel motion parameters such as velocity and tire slip are the other factors which impact on tire rolling resistance. According to same studies about the rolling resistance of the wheel, the wheel is significantly affected by the dynamic load. Tire inflation pressure impacted on rolling resistance of tires that were moving on hard surfaces. Studies showed that the rolling resistance of tires with low inflation pressure (less than 100 kPa was too high. According to Zoz and Griss researches, increasing the tire pressure increases rolling resistance on soft soil but reduces the rolling resistance of on-road tires and tire-hard surface interaction. Based on these reports, the effect of velocity on tire rolling resistance for tractors and vehicles with low velocity (less than 5 meters per second is usually insignificant. According to Self and Summers studies, rolling resistance of the wheel is dramatically affected by dynamic load on the wheel. Artificial Neural Network is one of the best computational methods capable of complex regression estimation which is an advantage of this method compared with

  8. Analysis of power wheeling services

    Energy Technology Data Exchange (ETDEWEB)

    Tepel, R.C.; Jewell, W.; Johnson, R.; Maddigan, R.

    1986-11-01

    Purpose of this study is to examine existing wheeling arrangements to determine the terms of the agreements, to analyze the terms relative to regulatory goals, and finally, to suggest ways in which the arrangements can be modified to lead to outcomes more closely in line with the goals. The regulatory goals that are considered are: Does the arrangement meet the revenue requirement of the wheeling firm. Is efficient use promoted. Are the costs fairly apportioned. And, is the arrangement practical and feasible to implement.

  9. Wheels With Sense

    Science.gov (United States)

    Cambridge, Dwayne; Clauss, Douglas; Hewson, Fraser; Brown, Robert; Hisrich, Robert; Taylor, Cyrus

    2002-10-01

    We describe a student intrapreneurial project in the Physics Entrepreneurship Program at Case Western Reserve University. At the request of a major fortune 100 company, a study has been made of the technical and marketing issues for a new business of selling sensors on commercial vehicle wheels for monitoring pressure, temperature, rotations, and vibrations, as well as providing identification. The nature of the physics involved in the choice of the appropriate device such as capacitive or piezoresistive sensors is discussed, along with the possibility of MEMS (micro-electro-mechanical systems) technology and RFID (radiofrequency identification) readout on wheels. Five options (status quo, in-house development, external business acquisition, a large business national partnership, and a small-business Cleveland consortium partnership) were studied from both technological and business perspectives to commercialize the technology. The decision making process for making a choice is explained.

  10. Do We Blindly Trust Self-Driving Cars

    DEFF Research Database (Denmark)

    Egedal Andersen, Kamilla; Köslich, Simon; Pedersen, Bjarke Maigaard Kjær

    2017-01-01

    - to-day activities, such as driving a car, we carried out a series of experiments with an autonomous car simulator. Partici- pants (N=73) engaged in a scenario with no, correct or false audible information regarding the state of traffic around the self-driving vehicle, and were told they could assume...

  11. Dynamic Modeling and Vibration Analysis for the Vehicles with Rigid Wheels Based on Wheel-Terrain Interaction Mechanics

    Directory of Open Access Journals (Sweden)

    Jianfeng Wang

    2015-01-01

    Full Text Available The contact mechanics for a rigid wheel and deformable terrain are complicated owing to the rigid flexible coupling characteristics. Bekker’s equations are used as the basis to establish the equations of the sinking rolling wheel, to vertical load pressure relationship. Since vehicle movement on the Moon is a complex and on-going problem, the researcher is poised to simplify this problem of vertical loading of the wheel. In this paper, the quarter kinetic models of a manned lunar rover, which are both based on the rigid road and deformable lunar terrain, are used as the simulation models. With these kinetic models, the vibration simulations were conducted. The simulation results indicate that the quarter kinetic model based on the deformable lunar terrain accurately reflects the deformable terrain’s influence on the vibration characteristics of a manned lunar rover. Additionally, with the quarter kinetic model of the deformable terrain, the vibration simulations of a manned lunar rover were conducted, which include a parametric analysis of the wheel parameters, vehicle speed, and suspension parameters. The results show that a manned lunar rover requires a lower damping value and stiffness to achieve better vibration performance.

  12. A Modular Approach for a Family of Ground Mobile Robots

    Directory of Open Access Journals (Sweden)

    Giuseppe Quaglia

    2013-07-01

    Full Text Available This paper deals with Epi.q, a family of mobile robots whose main characteristic is a wheel-legged hybrid locomotion. These multi-purpose robots can be successfully exploited for security and surveillance tasks. The document presents state of the art security robotics, the Epi.q mechanical architecture, the concept behind the robot driving unit, three prototypes and the design of a new one.

  13. Diagnostics of the wheel thread of railway rolling stock

    Directory of Open Access Journals (Sweden)

    S. Yu. Buryak

    2013-02-01

    Full Text Available Purpose. At present, the devastating impact of faulty wheels on rails on the move is a major problem of railway transport. This factor is one of the most important, which causes the shift from traditional manual methods of verification and external examination to the automated diagnostic system of rolling stock in operation. Methodology. To achieve this goal the main types of wheel damages and the way they appear are analyzed. The methods for defects and abnormalities of the wheel thread determining as well as their advantages and disadvantages were presented. Nowadays these methods are under usage in both the international practice and in the one of the CIS countries. Findings. The faulty wheel sound on the move was researched and analyzed. The necessity of using the automated system, enabling one to reduce significantly the human factor is substantiated. Originality. The method to determine the wheel thread damage on the basis of a sound diagnostic is proposed. Practical value. Automatic tracking system of the wheels condition allows performing their more qualitative diagnostics, detecting a fault at the early stage and forecasting the rate of its extension. Besides detecting the location of the faulty wheel in the rolling stock, it is also possible to trace the dynamics of the fault extension and to give the recommendations on how to eliminate it.

  14. TeenDrivingPlan effectiveness: the effect of quantity and diversity of supervised practice on teens' driving performance.

    Science.gov (United States)

    Mirman, Jessica H; Albert, W Dustin; Curry, Allison E; Winston, Flaura K; Fisher Thiel, Megan C; Durbin, Dennis R

    2014-11-01

    The large contribution of inexperience to the high crash rate of newly licensed teens suggests that they enter licensure with insufficient skills. In a prior analysis, we found moderate support for a direct effect of a web-based intervention, the TeenDrivingPlan (TDP), on teens' driving performance. The purpose of the present study was to identify the mechanisms by which TDP may be effective and to extend our understanding of how teens learn to drive. A randomized controlled trial conducted with teen permit holders and parent supervisors (N = 151 dyads) was used to determine if the effect of TDP on driver performance operated through five hypothesized mediators: (1) parent-perceived social support; (2) teen-perceived social support; (3) parent engagement; (4) practice quantity; and (5) practice diversity. Certified driving evaluators, blinded to teens' treatment allocation, assessed teens' driving performance 24 weeks after enrollment. Mediator variables were assessed on self-report surveys administered periodically over the study period. Exposure to TDP increased teen-perceived social support, parent engagement, and practice diversity. Both greater practice quantity and diversity were associated with better driving performance, but only practice diversity mediated the relationship between TDP and driver performance. Practice diversity is feasible to change and increases teens' likelihood of completing a rigorous on-road driving assessment just before licensure. Future research should continue to identify mechanisms that diversify practice driving, explore complementary ways to help families optimize the time they spend on practice driving, and evaluate the long-term effectiveness of TDP. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  15. Design procedure for a wind-wheel with self-adjusting blade mechanism

    Directory of Open Access Journals (Sweden)

    Gennady A. Oborsky

    2014-12-01

    Full Text Available Developed is a wind-wheel design equipped with the self-adjusting blade. The blade is positioned eccentrically to the balance wheel and can freely rotate around its axis. Elaborated is the method of calculating the energy characteristics for a wind-wheel with the self-adjusting blade, considering not only the wind force but the force of air counter flow resistance to the blade’s rotation. Initially, the blade being located at an angle α = 45 to the wheel rotation plane, the air flow rotates the wheel with the maximum force. Thus, the speed of rotation increases that involves the increase in air counter flow resistance and results in blade turning with respective angle α reduction. This, consequently, reduces the torque. When the torsional force and the resistance enter into equilibrium, the blade takes a certain angle α, and the wheel speed becomes constant. This wind-wheel design including a self-adjusting blade allows increasing the air flow load ratio when compared to the wind-wheel equipped with a jammed blade.

  16. Estimation of longitudinal force, lateral vehicle speed and yaw rate for four-wheel independent driven electric vehicles

    Science.gov (United States)

    Chen, Te; Xu, Xing; Chen, Long; Jiang, Haobing; Cai, Yingfeng; Li, Yong

    2018-02-01

    Accurate estimation of longitudinal force, lateral vehicle speed and yaw rate is of great significance to torque allocation and stability control for four-wheel independent driven electric vehicle (4WID-EVs). A fusion method is proposed to estimate the longitudinal force, lateral vehicle speed and yaw rate for 4WID-EVs. The electric driving wheel model (EDWM) is introduced into the longitudinal force estimation, the longitudinal force observer (LFO) is designed firstly based on the adaptive high-order sliding mode observer (HSMO), and the convergence of LFO is analyzed and proved. Based on the estimated longitudinal force, an estimation strategy is then presented in which the strong tracking filter (STF) is used to estimate lateral vehicle speed and yaw rate simultaneously. Finally, co-simulation via Carsim and Matlab/Simulink is carried out to demonstrate the effectiveness of the proposed method. The performance of LFO in practice is verified by the experiment on chassis dynamometer bench.

  17. 77 FR 70478 - RG Steel Wheeling, LLC, Wheeling Office, A Division Of RG Steel, LLC, Including On-Site Leased...

    Science.gov (United States)

    2012-11-26

    ... Unlimited and Green Energy Initiatives LLC, Including Workers Whose Wages Were Reported Through Severstal..., Wheeling Office, a division of RG Steel, LLC, including on-site leased workers from Pro Unlimited and Green Energy Initiatives, LLC, Wheeling, West Virginia (TA-W-81,880) and Mountain State Carbon, LLC, including...

  18. Wheel-running attenuates intravenous cocaine self-administration in rats: sex differences.

    Science.gov (United States)

    Cosgrove, Kelly P; Hunter, Robb G; Carroll, Marilyn E

    2002-10-01

    This experiment examines the effect of access to a running-wheel on intravenous cocaine self-administration in male and female rats. Rats maintained at 85% of their free-feeding body weight were first exposed to the running-wheel alone during the 6-h sessions until behavior stabilized for 14 days. Intravenous cannulae were then implanted, and the rats were trained to self-administer a low dose of cocaine (0.2 mg/kg) under a fixed-ratio (FR 1) schedule during the 6-h sessions, while the wheel remained inactive and cocaine self-administration stabilized (cocaine-only condition). Next, the wheel access and cocaine self-administration were concurrently available followed by a period of cocaine-only. Behavior was allowed to stabilize for 10 days at each phase. During wheel access, cocaine infusions decreased by 21.9% in males and 70.6% in females compared to the cocaine-only condition; the effect was statistically significant in females. Infusions increased to baseline levels when wheel access was terminated. When cocaine infusions were concurrently available, wheel revolutions were reduced by 63.7% and 61.5% in males and females, respectively, compared to the wheel-only condition. This result did not differ due to sex, but it was statistically significant when data from males and females were combined. These results indicate that wheel-running activity had a greater suppressant effect on cocaine self-administration in females than in males, and in females, wheel-running and cocaine self-administration are substitutable as reinforcers.

  19. High-Risk Driving Behaviors among Adolescent Binge-Drinkers

    Science.gov (United States)

    Marcotte, Thomas D.; Bekman, Nicole M.; Meyer, Rachel A.; Brown, Sandra A.

    2013-01-01

    Background Binge drinking is common among adolescents. Alcohol use, and binge-drinking in particular, has been associated with neurocognitive deficits as well as risk-taking behaviors, which may contribute to negative driving outcomes among adolescents even while sober. Objectives To examine differences in self-reported driving behaviors between adolescent binge-drinkers and a matched sample of controls, including (a) compliance with graduated licensing laws, (b) high risk driving behaviors, and (c) driving outcomes (crashes, traffic tickets). Methods The present study examined driving behaviors and outcomes in adolescent recent binge drinkers (n=21) and demographically and driving history matched controls (n=17), ages 16-18. Results Binge drinkers more frequently violated graduated licensing laws (e.g., driving late at night), and engaged in more “high risk” driving behaviors, such as speeding and using a cell-phone while driving. Binge drinkers had more traffic tickets, crashes and “near crashes” than the control group. In a multivariate analysis, binge drinker status and speeding were the most robust predictors of a crash. Conclusion Binge drinking teens consistently engage in more dangerous driving behaviors and experience more frequent crashes and traffic tickets. They are also less compliant with preventative restrictions placed on youth while they are learning critical safe driving skills. Scientific Significance These findings highlight a need to examine the contribution of underlying traits (such as sensation seeking) and binge-related cognitive changes to these high-risk driving behaviors, which may assist researchers in establishing alternative prevention and policy efforts targeting this population. PMID:22324748

  20. Design of the hydraulic shock absorbers characteristics using relative springs deflections at general excitation of the bus wheels

    Directory of Open Access Journals (Sweden)

    Polach P.

    2010-12-01

    Full Text Available The air-pressure-controlled hydraulic shock absorbers of axles’ air suspension are capable of changing their damping forces in dependence on air pressure in air springs. Due to the possibility of improving dynamic properties of all vehicles that use the axles’ air suspension, BRANO a.s., the Czech producer of shock absorbers, developed semi-active air-pressure-controlled hydraulic telescopic shock absorbers. The force-velocity characteristics of the controlled shock absorbers were designed on the basis of relative deflections of the air springs. As a criterion for the design of the optimum characteristics of the controlled shock absorbers the maximum similarity of dynamic responses of multibody models of the SOR C 12 bus for all the considered weights to the dynamic response of the reference multibody model was chosen. Time histories of relative deflections of the axles’ air springs determined during the simulations are compared. Simulations of running over an obstacle with all the wheels were originally chosen (symmetric kinematic excitation of wheels. Verification of the suitability of the designed force-velocity characteristics of the APCSA described in this paper is performed on the basis of the simulations of general kinematic excitation of wheels. Driving on the artificially created test track according to the ŠKODA VÝZKUM methodology was chosen.

  1. Wheel running decreases the positive reinforcing effects of heroin.

    Science.gov (United States)

    Smith, Mark A; Pitts, Elizabeth G

    2012-01-01

    The purpose of this study was to examine the effects of voluntary wheel running on the positive reinforcing effects of heroin in rats with an established history of drug self-administration. Rats were assigned to sedentary (no wheel) and exercise (wheel) conditions and trained to self-administer cocaine under positive reinforcement contingencies. Rats acquiring cocaine self-administration were then tested with various doses of heroin during daily test sessions. Sedentary rats self-administered more heroin than exercising rats, and this effect was greatest at low and moderate doses of heroin. These data suggest that voluntary wheel running decreases the positive reinforcing effects of heroin.

  2. Modeling and Recognizing Driver Behavior Based on Driving Data: A Survey

    OpenAIRE

    Wang, Wenshuo; Xi, Junqiang; Chen, Huiyan

    2014-01-01

    In recent years, modeling and recognizing driver behavior have become crucial to understanding intelligence transport systems, human-vehicle systems, and intelligent vehicle systems. A wide range of both mathematical identification methods and modeling methods of driver behavior are presented from the control point of view in this paper based on the driving data, such as the brake/throttle pedal position and the steering wheel angle, among others. Subsequently, the driver’s characteristics de...

  3. Habituation contributes to the decline in wheel running within wheel-running reinforcement periods.

    Science.gov (United States)

    Belke, Terry W; McLaughlin, Ryan J

    2005-02-28

    Habituation appears to play a role in the decline in wheel running within an interval. Aoyama and McSweeney [Aoyama, K., McSweeney, F.K., 2001. Habituation contributes to within-session changes in free wheel running. J. Exp. Anal. Behav. 76, 289-302] showed that when a novel stimulus was presented during a 30-min interval, wheel-running rates following the stimulus increased to levels approximating those earlier in the interval. The present study sought to assess the role of habituation in the decline in running that occurs over a briefer interval. In two experiments, rats responded on fixed-interval 30-s schedules for the opportunity to run for 45 s. Forty reinforcers were completed in each session. In the first experiment, the brake and chamber lights were repeatedly activated and inactivated after 25 s of a reinforcement interval had elapsed to assess the effect on running within the remaining 20 s. Presentations of the brake/light stimulus occurred during nine randomly determined reinforcement intervals in a session. In the second experiment, a 110 dB tone was emitted after 25 s of the reinforcement interval. In both experiments, presentation of the stimulus produced an immediate decline in running that dissipated over sessions. No increase in running following the stimulus was observed in the first experiment until the stimulus-induced decline dissipated. In the second experiment, increases in running were observed following the tone in the first session as well as when data were averaged over several sessions. In general, the results concur with the assertion that habituation plays a role in the decline in wheel running that occurs within both long and short intervals. (c) 2004 Elsevier B.V. All rights reserved.

  4. Milestone reached for the Big Wheels of the Muon Spectrometer

    CERN Multimedia

    Sandro Palestini

    The assembly and integration of the Big Wheels sectors of the Muon Spectrometer is reaching its conclusion, with only a few sectors of Wheel TGC-A-3 remaining on the assembly stations in building 180. The six trigger chambers (TGCs) wheels and two precision chambers wheels (MDTs) contain in total 104 sectors, which were assembled, equipped with detectors and fully tested over a period of two years. The few remaining Big Wheel sectors still stored in building 180 Most of the sectors left building 180 over the last twelve months, and form the six Wheels currently installed in the ATLAS detector. The remaining two will be installed before the end of the summer. The commitment of the personnel from the many teams who contributed to different parts of the project was essential to its success. In particular, teams coming from countries of different traditions and languages, such as China, Israel, Japan, Pakistan, Russia and USA contributed and collaborated very effectively to the timely completion of the p...

  5. 30 CFR 57.15014 - Eye protection when operating grinding wheels.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Eye protection when operating grinding wheels. 57.15014 Section 57.15014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... grinding wheels. Face shields or goggles in good condition shall be worn when operating a grinding wheel...

  6. Stereotypic wheel running decreases cortical activity in mice

    Science.gov (United States)

    Fisher, Simon P.; Cui, Nanyi; McKillop, Laura E.; Gemignani, Jessica; Bannerman, David M.; Oliver, Peter L.; Peirson, Stuart N.; Vyazovskiy, Vladyslav V.

    2016-01-01

    Prolonged wakefulness is thought to gradually increase ‘sleep need' and influence subsequent sleep duration and intensity, but the role of specific waking behaviours remains unclear. Here we report the effect of voluntary wheel running during wakefulness on neuronal activity in the motor and somatosensory cortex in mice. We find that stereotypic wheel running is associated with a substantial reduction in firing rates among a large subpopulation of cortical neurons, especially at high speeds. Wheel running also has longer-term effects on spiking activity across periods of wakefulness. Specifically, cortical firing rates are significantly higher towards the end of a spontaneous prolonged waking period. However, this increase is abolished when wakefulness is dominated by running wheel activity. These findings indicate that wake-related changes in firing rates are determined not only by wake duration, but also by specific waking behaviours. PMID:27748455

  7. 30 CFR 56.15014 - Eye protection when operating grinding wheels.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Eye protection when operating grinding wheels... MINES Personal Protection § 56.15014 Eye protection when operating grinding wheels. Face shields or goggles in good condition shall be worn when operating a grinding wheel. [53 FR 32526, Aug. 25, 1988] ...

  8. Study on Power Switching Process of a Hybrid Electric Vehicle with In-Wheel Motors

    Directory of Open Access Journals (Sweden)

    Shaohua Wang

    2016-01-01

    Full Text Available Hybrid electric vehicles with in-wheel motors (IWM achieve a variety of driving modes by two power sources—the engine and the IWM. One of the critical problems that exists in such vehicle is the different transient characteristics between the engine and the IWM. Therefore, switching processes between the power sources have noteworthy impacts on vehicle dynamics and driving performance. For the particular switching process of the pure electric mode to the engine driving mode, a specific control strategy coordinating clutch torque, motor torque, and engine torque was proposed to solve drivability issues caused by inconsistent responses of different power sources during the mode transition. The specific switching process could be described as follows: the engine was started by IWM with the clutch serving as a key enabling actuator, dynamic torque compensation through IWM was implemented after engine started, and, meanwhile, engine speed was controlled to track the target speed through the closed loop PID control strategy. The bench tests results showed that the vehicle jerk caused during mode switching was reduced and fast and smooth mode switching was realized, which leads to the improvement of vehicle’s riding comfort.

  9. Magnetic power conversion with machines containing full or porous wheel heat exchangers

    Science.gov (United States)

    Egolf, Peter W.; Kitanovski, Andrej; Diebold, Marc; Gonin, Cyrill; Vuarnoz, Didier

    2009-04-01

    A first part of the article contains a thermodynamic theory describing the temperature distribution in a Curie wheel. The occurring nonlinear ordinary differential equation has an analytical solution. If a Curie wheel is stabilized by levitation, it is named Palmy wheel. These wheels show a full structure, and because of this reason, their uptake of heat from a flame (Curie wheel) or by (solar) light absorption (Palmy wheel) only on the periphery of a cylinder is very limited. To improve the method, a modification of the principle by introducing a convective heat transport into a porous wheel is discussed. By this the power conversion rate from a heat flux to mechanical and electric power is very much increased. The second part of the article presents results of a theoretical/numerical study on the efficiencies of magnetic power conversion plants operating with porous wheels. Furthermore, these efficiencies—which are promising—are compared with those of existing power conversion plants, as e.g. geothermal binary cycle power plants.

  10. Magnetic power conversion with machines containing full or porous wheel heat exchangers

    International Nuclear Information System (INIS)

    Egolf, Peter W.; Kitanovski, Andrej; Diebold, Marc; Gonin, Cyrill; Vuarnoz, Didier

    2009-01-01

    A first part of the article contains a thermodynamic theory describing the temperature distribution in a Curie wheel. The occurring nonlinear ordinary differential equation has an analytical solution. If a Curie wheel is stabilized by levitation, it is named Palmy wheel. These wheels show a full structure, and because of this reason, their uptake of heat from a flame (Curie wheel) or by (solar) light absorption (Palmy wheel) only on the periphery of a cylinder is very limited. To improve the method, a modification of the principle by introducing a convective heat transport into a porous wheel is discussed. By this the power conversion rate from a heat flux to mechanical and electric power is very much increased. The second part of the article presents results of a theoretical/numerical study on the efficiencies of magnetic power conversion plants operating with porous wheels. Furthermore, these efficiencies-which are promising-are compared with those of existing power conversion plants, as e.g. geothermal binary cycle power plants

  11. Texting and accessing the web while driving: traffic citations and crashes among young adult drivers.

    Science.gov (United States)

    Cook, Jerry L; Jones, Randall M

    2011-12-01

    We examined relations between young adult texting and accessing the web while driving with driving outcomes (viz. crashes and traffic citations). Our premise is that engaging in texting and accessing the web while driving is not only distracting but that these activities represent a pattern of behavior that leads to an increase in unwanted outcomes, such as crashes and citations. College students (N = 274) on 3 campuses (one in California and 2 in Utah) completed an electronic questionnaire regarding their driving experience and cell phone use. Our data indicate that 3 out of 4 (74.3%) young adults engage in texting while driving, over half on a weekly basis (51.8%), and some engage in accessing the web while driving (16.8%). Data analysis revealed a relationship between these cell phone behaviors and traffic citations and crashes. The findings support Jessor and Jessor's (1977) "problem behavior syndrome" by showing that traffic citations are related to texting and accessing the web while driving and that crashes are related to accessing the web while driving. Limitations and recommendations are discussed.

  12. Numerical and experimental analysis of a solid desiccant wheel

    Directory of Open Access Journals (Sweden)

    Koronaki Irene P.

    2016-01-01

    Full Text Available The rotary desiccant dehumidifier is an important component which can be used in air conditioning systems in order to reduce the electrical energy consumption and introduce renewable energy sources. In this study a one dimensional gas side resistance model is presented for predicting the performance of the desiccant wheel. Measurements from two real sorption wheels are used in order to validate the model. One wheel uses silica gel as desiccant material and the other lithium chloride. The simulation results are in good agreement with the experimental data. The model is used to compare the counter flow with the co-current wheel arrangements and to explain why the counter flow one is more efficient for air dehumidification.

  13. Technics study on high accuracy crush dressing and sharpening of diamond grinding wheel

    Science.gov (United States)

    Jia, Yunhai; Lu, Xuejun; Li, Jiangang; Zhu, Lixin; Song, Yingjie

    2011-05-01

    Mechanical grinding of artificial diamond grinding wheel was traditional wheel dressing process. The rotate speed and infeed depth of tool wheel were main technics parameters. The suitable technics parameters of metals-bonded diamond grinding wheel and resin-bonded diamond grinding wheel high accuracy crush dressing were obtained by a mount of experiment in super-hard material wheel dressing grind machine and by analysis of grinding force. In the same time, the effect of machine sharpening and sprinkle granule sharpening was contrasted. These analyses and lots of experiments had extent instruction significance to artificial diamond grinding wheel accuracy crush dressing.

  14. Riding the Ferris Wheel: A Sinusoidal Model

    Science.gov (United States)

    Mittag, Kathleen Cage; Taylor, Sharon E.

    2011-01-01

    When thinking of models for sinusoidal waves, examples such as tides of the ocean, daily temperatures for one year in your town, light and sound waves, and certain types of motion are used. Many textbooks [1, p. 222] also present a "Ferris wheel description problem" for students to work. This activity takes the Ferris wheel problem out of the…

  15. 49 CFR 230.112 - Wheels and tires.

    Science.gov (United States)

    2010-10-01

    ... wheels mounted on the same axle shall not vary more than 1/4 inch. (d) Tire thickness. Wheels may not have tires with a minimum thickness less than that indicated in the table in this paragraph (d). When... the minimum thickness of tires may be as much below the limits specified earlier in this paragraph (d...

  16. Effect of short-term prefeeding and body weight on wheel running and responding reinforced by the opportunity to run in a wheel.

    Science.gov (United States)

    Belke, Terry W; Pierce, W David; Jensen, K

    2004-07-30

    A biobehavioural analysis of activity anorexia suggests that the motivation for physical activity is regulated by food supply and body weight. In the present experiment, food allocation was varied within subjects by prefeeding food-deprived rats 0, 5, 10 and 15 g of food before sessions of lever pressing for wheel-running reinforcement. The experiment assessed the effects of prefeeding on rates of wheel running, lever pressing, and postreinforcement pausing. Results showed that prefeeding animals 5 g of food had no effect. Prefeeding 10 g of food reduced lever pressing for wheel running and rates of wheel running without a significant change in body weight; the effect was, however, transitory. Prefeeding 15 g of food increased the animals' body weights, resulting in a sustained decrease of wheel running and lever pressing, and an increase in postreinforcement pausing. Overall the results indicate that the motivation for physical activity is regulated by changes in local food supply, but is sustained only when there is a concomitant change in body weight.

  17. Installation of the first of the big wheels of the ATLAS muon spectrometer, a thin gap chamber (TGC) wheel

    CERN Multimedia

    Claudia Marcelloni

    2006-01-01

    The muon spectrometer will include four big moving wheels at each end, each measuring 25 metres in diameter. Of the eight wheels in total, six will be composed of thin gap chambers for the muon trigger system and the other two will consist of monitored drift tubes (MDTs) to measure the position of the muons

  18. System Analysis of Flat Grinding Process with Wheel Face

    Directory of Open Access Journals (Sweden)

    T. N. Ivanova

    2014-01-01

    Full Text Available The paper presents a conducted system analysis of the flat grinding wheel face, considers the state parameters, input and output variables of subsystems, namely: machine tool, workpiece, grinding wheel, cutting fluids, and the contact area. It reveals the factors influencing the temperature and power conditions for the grinding process.Aim: conducting the system analysis of the flat grinding process with wheel face expects to enable a development of the system of grinding process parameters as a technical system, which will make it possible to evaluate each parameter individually and implement optimization of the entire system.One of the most important criteria in defining the optimal process conditions is the grinding temperature, which, to avoid defects appearance of on the surface of component, should not exceed the critical temperature values to be experimentally determined. The temperature criterion can be useful for choosing the conditions for the maximum defect-free performance of the mechanical face grinding. To define the maximum performance of defect-free grinding can also use other criteria such as a critical power density, indirectly reflecting the allowable thermal stress grinding process; the structure of the ground surface, which reflects the presence or absence of a defect layer, which is determined after the large number of experiments; flow range of the diamond layer.Optimal conditions should not exceed those of defect-free grinding. It is found that a maximum performance depends on the characteristics of circles and grade of processed material, as well as on the contact area and grinding conditions. Optimal performance depends on the diamond value (cost and specific consumption of diamonds in a circle.Above criteria require formalization as a function of the variable parameters of the grinding process. There is an option for the compromise of inter-criteria optimality, thereby providing a set of acceptable solutions, from

  19. Development of Trigger and Readout Electronics for the ATLAS New Small Wheel Detector Upgrade

    CERN Document Server

    Zhu, Junjie; The ATLAS collaboration

    2017-01-01

    The planned Phase-I and Phase-II upgrades of the LHC accelerator drastically impacts the ATLAS trigger and trigger rates. A replacement of the ATLAS innermost endcap muon station with a new small wheel (NSW) detector is planned for the second long shutdown period of 2019 - 2020. This upgrade will allow us to maintain a low pT threshold for single muon and excellent tracking capability even after the High-Luminosity LHC upgrade. The NSW detector will feature two new detector technologies, Resistive Micromegas and small-strip Thin Gap Chambers. Both detector technologies will provide trigger and tracking primitives. The total number of trigger and readout channels is about 2.4 millions, and the overall power consumption is expected to be about 75 kW. The electronics design will be implemented in some 8000 front-end boards including the design of four custom front-end ASICs capable to drive trigger and tracking primitives with high speed sterilizers to drive trigger candidates to the backend trigger processor sy...

  20. Out-of-round railway wheels—assessment of wheel tread irregularities in train traffic

    Science.gov (United States)

    Johansson, Anders

    2006-06-01

    Results from an extensive wheel measurement campaign performed in Sweden are given and discussed. Out-of-roundness (OOR), transverse profile and surface hardness of 99 wheels on passenger trains (X2 and intercity), freight trains, commuter trains (Regina) and underground trains (C20) were measured. Both tread and disc braked wheels were investigated. The selected wheels had travelled a distance of more than 100000 km, and the measurements were conducted when the train wagons/coaches had been taken out of traffic for maintenance, most of them due to reasons other than wheel OOR. Mechanical contact measurement methods were used. The highest roughness levels (higher than 20 dB re 1 μm for some wheels) were found on powered high-speed (X2) train wheels. The previously known polygonalization of C20 underground wheels is quantified. It is also verified that an initial irregularity is formed due to the clamping in a three-jaw chuck during profiling of new C20 wheels. Magnitudes and wavelength contents of measured wheel roughness are compared with corresponding measurements of rail roughness.

  1. Load-bearing processes in agricultural wheel-soil systems

    NARCIS (Netherlands)

    Tijink, F.G.J.

    1988-01-01

    In soil dynamics we distinguish between loosening and loadbearing processes. Load-bearing processes which can occur under agricultural rollers, wheels, and tyres are dealt with In this dissertation.

    We classify rollers, wheels, and tyres and treat some general aspects of these

  2. A Star-Wheel Stair-Climbing Wheelchair

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; WU Bo; JIN Ai-min; JIANG Shi-hong; ZHENG Yu-fei; ZHANG Shuai

    2014-01-01

    In order to achieve a wheelchair climb stairs function, this paper designs a star-wheel stair-climbing mechanism. Through the effect of the lock coupling, the star-wheel stair-climbing mechanism is formed to be fixed axis gear train or planetary gear train achieving flat-walking and stair-climbing functions. Crossing obstacle analysis obtains the maximum height and minimum width of obstacle which the wheelchair can cross. Stress-strain analysis in Solidworks simulation is performed to verify material strength.

  3. What Future for Student Engagement in Neo-Liberal Times?

    Science.gov (United States)

    Zepke, Nick

    2015-01-01

    The paper first examines the context that has given student engagement a very strong profile in higher education. It identifies neo-liberalism as the driving force in the present higher education context and argues that student engagement enjoys an elective affinity with it. While neo-liberalism is dominant, student engagement will be strong. But…

  4. Reduction of extinction and reinstatement of cocaine seeking by wheel running in female rats.

    Science.gov (United States)

    Zlebnik, Natalie E; Anker, Justin J; Gliddon, Luke A; Carroll, Marilyn E

    2010-03-01

    Previous work has shown that wheel running reduced the maintenance of cocaine self-administration in rats. In the present study, the effect of wheel running on extinction and reinstatement of cocaine seeking was examined. Female rats were trained to run in a wheel during 6-h sessions, and they were then catheterized and placed in an operant conditioning chamber where they did not have access to the wheel but were allowed to self-administer iv cocaine. Subsequently, rats were divided into four groups and were tested on the extinction and reinstatement of cocaine seeking while they had varying access to a wheel in an adjoining compartment. The four groups were assigned to the following wheel access conditions: (1) wheel running during extinction and reinstatement (WER), (2) wheel running during extinction and a locked wheel during reinstatement (WE), (3) locked wheel during extinction and wheel running during reinstatement (WR), and (4) locked wheel during extinction and reinstatement (WL). WE and WR were retested later to examine the effect of one session of wheel access on cocaine-primed reinstatement. There were no group differences in wheel revolutions, in rate of acquisition of cocaine self-administration, or in responding during maintenance when there was no wheel access. However, during extinction, WE and WER responded less than WR and WL. WR and WER had lower cocaine-primed reinstatement than WE and WL. One session of wheel exposure in WE also suppressed cocaine-primed reinstatement. Wheel running immediately and effectively reduced cocaine-seeking behavior, but concurrent access to running was necessary. Thus, exercise is a useful and self-sustaining intervention to reduce cocaine-seeking behavior.

  5. Elevator wheel

    Energy Technology Data Exchange (ETDEWEB)

    Zhornik, V.I.; Cherkov, Ye.M.; Simonov, A.A.

    1982-01-01

    An elevator wheel is suggested for unloading a sunken product from a bath of a heavy-average separator including discs of a bucket with inner walls, and covering sheets hinged to the buckets. In order to improve the degree of dehydration of the removed product, the inner wall of each bucket is made of sheets installed in steps with gaps of one in relation to the other.

  6. Innovative grinding wheel design for cost-effective machining of advanced ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Licht, R.H.; Kuo, P.; Liu, S.; Murphy, D.; Picone, J.W.; Ramanath, S.

    2000-05-01

    This Final Report covers the Phase II Innovative Grinding Wheel (IGW) program in which Norton Company successfully developed a novel grinding wheel for cost-effective cylindrical grinding of advanced ceramics. In 1995, Norton Company successfully completed the 16-month Phase I technical effort to define requirements, design, develop, and evaluate a next-generation grinding wheel for cost-effective cylindrical grinding of advanced ceramics using small prototype wheels. The Phase II program was initiated to scale-up the new superabrasive wheel specification to larger diameters, 305-mm to 406-mm, required for most production grinding of cylindrical ceramic parts, and to perform in-house and independent validation grinding tests.

  7. IoT On-Board System for Driving Style Assessment.

    Science.gov (United States)

    Jachimczyk, Bartosz; Dziak, Damian; Czapla, Jacek; Damps, Pawel; Kulesza, Wlodek J

    2018-04-17

    The assessment of skills is essential and desirable in areas such as medicine, security, and other professions where mental, physical, and manual skills are crucial. However, often such assessments are performed by people called “experts” who may be subjective and are able to consider a limited number of factors and indicators. This article addresses the problem of the objective assessment of driving style independent of circumstances. The proposed objective assessment of driving style is based on eight indicators, which are associated with the vehicle’s speed, acceleration, jerk, engine rotational speed and driving time. These indicators are used to estimate three driving style criteria: safety , economy , and comfort . The presented solution is based on the embedded system designed according to the Internet of Things concept. The useful data are acquired from the car diagnostic port—OBD-II—and from an additional accelerometer sensor and GPS module. The proposed driving skills assessment method has been implemented and experimentally validated on a group of drivers. The obtained results prove the system’s ability to quantitatively distinguish different driving styles. The system was verified on long-route tests for analysis and could then improve the driver’s behavior behind the wheel. Moreover, the spider diagram approach that was used established a convenient visualization platform for multidimensional comparison of the result and comprehensive assessment in an intelligible manner.

  8. IoT On-Board System for Driving Style Assessment

    Directory of Open Access Journals (Sweden)

    Bartosz Jachimczyk

    2018-04-01

    Full Text Available The assessment of skills is essential and desirable in areas such as medicine, security, and other professions where mental, physical, and manual skills are crucial. However, often such assessments are performed by people called “experts” who may be subjective and are able to consider a limited number of factors and indicators. This article addresses the problem of the objective assessment of driving style independent of circumstances. The proposed objective assessment of driving style is based on eight indicators, which are associated with the vehicle’s speed, acceleration, jerk, engine rotational speed and driving time. These indicators are used to estimate three driving style criteria: safety, economy, and comfort. The presented solution is based on the embedded system designed according to the Internet of Things concept. The useful data are acquired from the car diagnostic port—OBD-II—and from an additional accelerometer sensor and GPS module. The proposed driving skills assessment method has been implemented and experimentally validated on a group of drivers. The obtained results prove the system’s ability to quantitatively distinguish different driving styles. The system was verified on long-route tests for analysis and could then improve the driver’s behavior behind the wheel. Moreover, the spider diagram approach that was used established a convenient visualization platform for multidimensional comparison of the result and comprehensive assessment in an intelligible manner.

  9. Behind the wheel and on the map: Genetic and environmental associations between drunk driving and other externalizing behaviors.

    Science.gov (United States)

    Quinn, Patrick D; Harden, K Paige

    2013-11-01

    Drunk driving, a major contributor to alcohol-related mortality, has been linked to a variety of other alcohol-related (e.g., Alcohol Dependence, early age at first drink) and non-alcohol-related externalizing behaviors. In a sample of 517 same-sex twin pairs from the National Longitudinal Study of Adolescent Health, we examined 3 conceptualizations of the etiology of drunk driving in relation to other externalizing behaviors. A series of behavioral-genetic models found consistent evidence for drunk driving as a manifestation of genetic vulnerabilities toward a spectrum of alcohol-related and non-alcohol-related externalizing behaviors. Most notably, multidimensional scaling analyses produced a genetic "map" with drunk driving located near its center, supporting the strength of drunk driving's genetic relations with a broad range of externalizing behaviors. In contrast, nonshared environmental associations with drunk driving were weaker and more diffuse. Drunk driving may be a manifestation of genetic vulnerabilities toward a broad externalizing spectrum. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  10. Underwater Sound Propagation from Marine Pile Driving.

    Science.gov (United States)

    Reyff, James A

    2016-01-01

    Pile driving occurs in a variety of nearshore environments that typically have very shallow-water depths. The propagation of pile-driving sound in water is complex, where sound is directly radiated from the pile as well as through the ground substrate. Piles driven in the ground near water bodies can produce considerable underwater sound energy. This paper presents examples of sound propagation through shallow-water environments. Some of these examples illustrate the substantial variation in sound amplitude over time that can be critical to understand when computing an acoustic-based safety zone for aquatic species.

  11. A mechanical model for deformable and mesh pattern wheel of lunar roving vehicle

    Science.gov (United States)

    Liang, Zhongchao; Wang, Yongfu; Chen, Gang (Sheng); Gao, Haibo

    2015-12-01

    As an indispensable tool for astronauts on lunar surface, the lunar roving vehicle (LRV) is of great significance for manned lunar exploration. An LRV moves on loose and soft lunar soil, so the mechanical property of its wheels directly affects the mobility performance. The wheels used for LRV have deformable and mesh pattern, therefore, the existing mechanical theory of vehicle wheel cannot be used directly for analyzing the property of LRV wheels. In this paper, a new mechanical model for LRV wheel is proposed. At first, a mechanical model for a rigid normal wheel is presented, which involves in multiple conventional parameters such as vertical load, tangential traction force, lateral force, and slip ratio. Secondly, six equivalent coefficients are introduced to amend the rigid normal wheel model to fit for the wheels with deformable and mesh-pattern in LRV application. Thirdly, the values of the six equivalent coefficients are identified by using experimental data obtained in an LRV's single wheel testing. Finally, the identified mechanical model for LRV's wheel with deformable and mesh pattern are further verified and validated by using additional experimental results.

  12. Wheels and Tires: Understanding the Numbers on the Sides of Tires Might Lead to Longer Life Tires and Improved Driving Safety

    Science.gov (United States)

    Ritz, John M.

    2005-01-01

    Automotive wheels and tires require knowledge to understand their specifications and use. While the durability and useful life of tires have increased substantially over the last several decades, in all probability consumers will purchase a number of vehicle tires over their lifetime. Knowing how they are made and what the numbers mean will assist…

  13. Lateral ring metal elastic wheel absorbs shock loading

    Science.gov (United States)

    Galan, L.

    1966-01-01

    Lateral ring metal elastic wheel absorbs practically all shock loading when operated over extremely rough terrain and delivers only a negligible shock residue to associated suspension components. The wheel consists of a rigid aluminum assembly to which lateral titanium ring flexible elements with treads are attached.

  14. Teens and distracted driving : texting, talking and other uses of the cell phone behind the wheel

    Science.gov (United States)

    2009-11-16

    This study investigated cell phone use and texting while driving, by teenage drivers, in the United States. It found that one third of 16-17 year old teenagers who text do so while driving. 50% of 16-17 year old teenagers have spoken on cell phones w...

  15. Risky Driving Behaviours among Medical Students in Erbil, Iraq

    Directory of Open Access Journals (Sweden)

    Nazar P. Shabila

    2015-08-01

    Full Text Available Objectives: This study aimed to assess risky driving behaviours among medical students in Erbil, Iraq, and to explore the relationship between risky driving behaviours and perceptions of risky driving. Methods: This self-administered questionnaire-based survey was conducted from January to May 2014 among a random sample of 400 medical students at Hawler Medical University in Erbil. The questionnaire was designed to assess the frequency of engagement in 21 risky driving behaviours, the perceived risk of each behaviour and the preference for each behaviour as ranked on a 5-point scale. Results: A total of 386 students responded to the survey (response rate: 96.5%. Of these, 211 reported that they currently drove a vehicle (54.7%. Drivers most frequently engaged in the following behaviours: playing loud music (35.9%, speeding (30.4%, allowing front seat passengers to not wear seat belts (27.9% and using mobile phones (27.7%. Least frequent driving behaviours included not stopping at a red light (3.9%, driving while sleepy (4.4%, driving after a mild to moderate intake of alcohol (4.5% and drunk driving (6.4%. Mean risky driving behaviour scores were significantly higher among males (P 20-year-olds (P = 0.028. There was a significant positive relationship between the preference for risky behaviours and risky driving behaviours (beta = 0.44; P <0.001. Conclusion: Medical students in Erbil reported high frequencies of several serious risky driving behaviours. The preference for risky behaviours was found to be an important predictor of risky driving behaviours among medical students in Erbil.

  16. Wheel slip dump valve for railway braking system

    Science.gov (United States)

    Zhang, Xuan; Zhang, LiHao; Li, QingXuan; Shi, YanTao

    2017-09-01

    As we all know, pneumatic braking system plays an important role in the safety of the whole vehicle. In the anti slip braking system, the pressure of braking cylinder can be adjusted by the quick power response of wheel slip dump valve, so that the lock situation won’t occur during vehicle service. During the braking of railway vehicles, the braking force provided by braking disc reduces vehicle’s speed. But the locking slip will happen due to the oversize of braking force or the reduction of sticking coefficient between wheel and rail. It will cause not only the decline of braking performance but also the increase of braking distance. In the meanwhile, it will scratch the wheel and influence the stable running of vehicles. Now, the speed of passenger vehicle has been increased. In order to shorten the braking distance as far as possible, sticking stickiness must be fully applied. So the occurrence probability of wheel slip is increased.

  17. Applied design methodology for lunar rover elastic wheel

    Science.gov (United States)

    Cardile, Diego; Viola, Nicole; Chiesa, Sergio; Rougier, Alessandro

    2012-12-01

    In recent years an increasing interest in the Moon surface operations has been experienced. In the future robotic and manned missions of Moon surface exploration will be fundamental in order to lay the groundwork for more ambitious space exploration programs. Surface mobility systems will be the key elements to ensure an efficient and safe Moon exploration. Future lunar rovers are likely to be heavier and able to travel longer distances than the previously developed Moon rover systems. The Lunar Roving Vehicle (LRV) is the only manned rover, which has so far been launched and used on the Moon surface. Its mobility system included flexible wheels that cannot be scaled to the heavier and longer range vehicles. Thus the previously developed wheels are likely not to be suitable for the new larger vehicles. Taking all these considerations into account, on the basis of the system requirements and assumptions, several wheel concepts have been discussed and evaluated through a trade-off analysis. Semi-empirical equations have been utilized to predict the wheel geometrical characteristics, as well as to estimate the motion resistances and the ability of the system to generate thrust. A numerical model has also been implemented, in order to define more into the details the whole wheel design, in terms of wheel geometry and physical properties. As a result of the trade-off analysis, the ellipse wheel concept has shown the best behavior in terms of stiffness, mass budget and dynamic performance. The results presented in the paper have been obtained in cooperation with Thales Alenia Space-Italy and Sicme motori, in the framework of a regional program called STEPS . STEPS-Sistemi e Tecnologie per l'EsPlorazione Spaziale is a research project co-financed by Piedmont Region and firms and universities of the Piedmont Aerospace District in the ambit of the P.O.R-F.E.S.R. 2007-2013 program.

  18. Experimental studies of breaking of elastic tired wheel under variable normal load

    Science.gov (United States)

    Fedotov, A. I.; Zedgenizov, V. G.; Ovchinnikova, N. I.

    2017-10-01

    The paper analyzes the braking of a vehicle wheel subjected to disturbances of normal load variations. Experimental tests and methods for developing test modes as sinusoidal force disturbances of the normal wheel load were used. Measuring methods for digital and analogue signals were used as well. Stabilization of vehicle wheel braking subjected to disturbances of normal load variations is a topical issue. The paper suggests a method for analyzing wheel braking processes under disturbances of normal load variations. A method to control wheel baking processes subjected to disturbances of normal load variations was developed.

  19. Color Wheel Windows

    Science.gov (United States)

    Leonard, Stephanie

    2012-01-01

    In this article, the author describes a painting and drawing lesson which was inspired by the beautiful circular windows found in cathedrals and churches (also known as "rose windows"). This two-week lesson would reinforce both the concept of symmetry and students' understanding of the color wheel. (Contains 1 online resource.)

  20. Bucket wheel excavator performances at Neyveli lignite mine

    Energy Technology Data Exchange (ETDEWEB)

    Kumaraswamy, S; Mozumdar, B K

    1987-03-01

    Bucket-wheel excavators have been in use at the Neyveli Lignite Mine in the State of Tamil Nadu, India, since the early nineteen-sixties. The mining environment has been particularly harsh for BWE application. The adverse influencing factors are the hardness of the over-burden formation, high abrasivity of rock and artesian ground water conditions. In this paper, the performances of the BWEs at Neyveli have been statistically analysed to determine the effects of physico-mechanical properties of overburden, blasting and rainfall on machine productivity, availability, wear-and-tear of bucket teeth, power consumption, production efficiency and cost of mining. An empirical relationship between the production efficiency, defined as the ratio of actual production rate to the theoretical one, and the bench height and width, height of slices, specific cutting resistance of the overburden material and its clay content, consumption of explosives, and conveyor length has been established.

  1. EMBEDDED CONTROL SYSTEM FOR MOBILE ROBOTS WITH DIFFERENTIAL DRIVE

    Directory of Open Access Journals (Sweden)

    Michal KOPČÍK

    2017-09-01

    Full Text Available This article deals with design and implementation of control system for mobile robots with differential drive using embedded system. This designed embedded system consists of single control board featuring ARM based microcontroller which control the peripherals in real time and perform all low-level motion control. Designed embedded system can be easily expanded with additional sensors, actuators or control units to enhance applicability of mobile robot. Designed embedded system also features build-in communication module, which can be used for data for data acquisition and control of the mobile robot. Control board was implemented on two different types of mobile robots with differential drive, one of which was wheeled and other was tracked. These mobile robots serve as testing platform for Fault Detection and Isolation using hardware and analytical redundancy using Multisensor Data Fusion based on Kalman filters.

  2. Study on general theory of kinematics and dynamics of wheeled mobile robots

    Science.gov (United States)

    Tsukishima, Takahiro; Sasaki, Ken; Takano, Masaharu; Inoue, Kenji

    1992-03-01

    This paper proposes a general theory of kinematics and dynamics of wheeled mobile robots (WMRs). Unlike robotic manipulators which are modeled as 3-dimensional serial link mechanism, WMRs will be modeled as planar linkage mechanism with multiple links branching out from the base and/or another link. Since this model resembles a tree with branches, it will be called 'tree-structured-link'. The end of each link corresponds to the wheel which is in contact with the floor. In dynamics of WMR, equation of motion of a WMR is derived from joint input torques incorporating wheel dynamics. The wheel dynamics determines forces and moments acting on wheels as a function of slip velocity. This slippage of wheels is essential in dynamics of WMR. It will also be shown that the dynamics of WMR reduces to kinematics when slippage of wheels is neglected. Furthermore, the equation of dynamics is rewritten in velocity input form, since most of industrial motors are velocity controlled.

  3. THE ANALISYS OF RAILWAY MULTI MOTORS ELECTRICAL DRIVE DYNAMIC

    Directory of Open Access Journals (Sweden)

    V. I. Khilmon

    2015-01-01

    Full Text Available The importance of multi motors electrical traction drive dynamic analysis is denoted by its large application in electrical driving railway vehicles. In this paper an analysis is presented for two inducton motors traction drive with frequency inverter, vector control, and speed sensors of each electrical drive. The goal of this work is the analysis of two induction motors electrical drive, taking into account parametric perturbations and also a limited moment of wheel-rail adhesion, by laboratory study and simulation. Because of difference between motor’s parameters, it is necessary for parallel work to select motors with identical resistances and inductive winding. For this purpose the parametric identification method was used for each electrical drive, and also for two parallel motors. The result of identification was used in control setting.The  slippage  of  the  traction  drives  is  difficult  to  reproduce  in  laboratory;  therefore a mathematical modeling and simulation of mechanical part with a traction force restriction, specific for railway transport, were carried out. The suggested simulation is built with account of elastic deformations in kinetic chain, transforming traction force. The model permits to study a dynamic system in various circumstances.The results of laboratory investigations and simulation of dynamic regimes for two motor electrical drives are presented in this article. The results of analysis show, that a minimal difference between any parameters of two motors, parallel connected to convertor, is important for the slippage stability.

  4. The Effects of Wear upon the Axial Profile of a Grinding Wheel in the Construction of Innovative Grinding Wheels for Internal Cylindrical Grinding

    OpenAIRE

    Nadolny, K.; Słowiński, B.

    2011-01-01

    The article describes the effects of wear upon the axial profile of a grinding wheel in the axial cylindrical grinding processes. This mechanism was used to develop a grinding wheel with zone diversified structure made of microcrystalline sintered corundum abrasive grains and vitrifies bond. Such a grinding wheel is characterized by the conical rough grinding zone that is made by grains of a relatively large size, and a cylindrical finish grinding zone with grains of a smaller size and can be...

  5. Conditioned taste avoidance induced by forced and voluntary wheel running in rats.

    Science.gov (United States)

    Forristall, J R; Hookey, B L; Grant, V L

    2007-03-01

    Voluntary exercise by rats running in a freely rotating wheel (free wheel) produces conditioned taste avoidance (CTA) of a flavored solution consumed before running [e.g., Lett, B.T., Grant, V.L., 1996. Wheel running induces conditioned taste aversion in rats trained while hungry and thirsty. Physiol. Behav. 59, 699-702]. Forced exercise, swimming or running, also produces CTA in rats [e.g., Masaki, T., Nakajima, S., 2006. Taste aversion induced by forced swimming, voluntary running, forced running, and lithium chloride injection treatments. Physiol. Behav. 88, 411-416]. Energy expenditure may be the critical factor in producing such CTA. If so, forced running in a motorized running wheel should produce CTA equivalent to that produced by a similar amount of voluntary running. In two experiments, we compared forced running in a motorized wheel with voluntary running in a free wheel. Mean distance run over 30 min was equated as closely as possible in the two apparatuses. Both types of exercise produced CTA relative to sedentary, locked-wheel controls. However, voluntary running produced greater CTA than forced running. We consider differences between running in the free and motorized wheels that may account for the differences in strength of CTA.

  6. Wheel-running activity modulates circadian organization and the daily rhythm of eating behavior

    Science.gov (United States)

    Pendergast, Julie S.; Branecky, Katrina L.; Huang, Roya; Niswender, Kevin D.; Yamazaki, Shin

    2014-01-01

    Consumption of high-fat diet acutely alters the daily rhythm of eating behavior and circadian organization (the phase relationship between oscillators in central and peripheral tissues) in mice. Voluntary wheel-running activity counteracts the obesogenic effects of high-fat diet and also modulates circadian rhythms in mice. In this study, we sought to determine whether voluntary wheel-running activity could prevent the proximate effects of high-fat diet consumption on circadian organization and behavioral rhythms in mice. Mice were housed with locked or freely rotating running wheels and fed chow or high-fat diet for 1 week and rhythms of locomotor activity, eating behavior, and molecular timekeeping (PERIOD2::LUCIFERASE luminescence rhythms) in ex vivo tissues were measured. Wheel-running activity delayed the phase of the liver rhythm by 4 h in both chow- and high-fat diet-fed mice. The delayed liver phase was specific to wheel-running activity since an enriched environment without the running wheel did not alter the phase of the liver rhythm. In addition, wheel-running activity modulated the effect of high-fat diet consumption on the daily rhythm of eating behavior. While high-fat diet consumption caused eating events to be more evenly dispersed across the 24 h-day in both locked-wheel and wheel-running mice, the effect of high-fat diet was much less pronounced in wheel-running mice. Together these data demonstrate that wheel-running activity is a salient factor that modulates liver phase and eating behavior rhythms in both chow- and high-fat-diet fed mice. Wheel-running activity in mice is both a source of exercise and a self-motivating, rewarding behavior. Understanding the putative reward-related mechanisms whereby wheel-running activity alters circadian rhythms could have implications for human obesity since palatable food and exercise may modulate similar reward circuits. PMID:24624109

  7. 49 CFR 238.119 - Rim-stamped straight-plate wheels.

    Science.gov (United States)

    2010-10-01

    ... input to the wheel during braking. (b) A rim-stamped straight-plate wheel shall not be used as a... that is periodically tread-braked for a short duration by automatic circuitry for the sole purpose of...

  8. Measuring the Dynamic Soil Response During Repeated Wheeling Using Seismic Methods

    DEFF Research Database (Denmark)

    Keller, Thomas; Carizzon, Marco; Berisso, Feto Esimo

    2013-01-01

    was performed with an agricultural tire (60 kN wheel load) on a gleyic Cambisol. We measured Vp using an acoustic (microseismic) device at various depths before, during (i.e., below the tire), and after wheeling. In addition, we measured bulk density and penetrometer resistance before and after wheeling...

  9. Seal plate with concentrate annular segments for a gas turbine engine

    International Nuclear Information System (INIS)

    Harris, D.P.; Light, S.H.

    1991-01-01

    This patent describes a gas turbine engine. It comprises a radial outflow, rotary compressor; a radial inflow turbine wheel; means coupling the compressor and the turbine wheel in slightly spaced back to back relating so that the turbine wheel may drive the compressor; a housing surrounding the compressor and the turbine wheel; and a stationary seal mounted on the housing and extending into the space between the compressor and the turbine wheel, the seal including a main sealing and support section adjacent the compressor and a multiple piece diaphragm mounted to the main section, but generally spaced therefrom, the pieces of the diaphragm being movable with respect to each other and with respect to the main section, and including a radially inner ring and a radially outer ring, one of the rings including a lip which overlaps an edge of the other of the rings, the lip and the edge being in sliding, sealing engagement

  10. Digital Politics: Mobilization, Engagement, and Participation

    OpenAIRE

    Koc-Michalska, K.; Lilleker, Darren

    2017-01-01

    The article provides insights into the driving forces that underpin new forms of political participation. Digital technologies offer opportunities for engaging in a wide range of civicallyoriented activities, each of which can contribute to deeper democratic engagement. Conventional acts of political participation are argued to be driven primarily by intrinsic motivations relating to self-efficacy and empowerment with participants feeling they can have influence over decision makers. Little r...

  11. The Wheels of Stress Go 'Round and 'Round

    Science.gov (United States)

    Brey, Rebecca A.; Clark, Susan E.

    2012-01-01

    "The Wheels of Stress Go Round and Round" teaching idea uses three activity wheels to reinforce stress-related content and concepts. After presenting a definition of stress, the instructor assists students in identifying stressors, and aids in formulating a list of negative, reactive behaviors and a list of positive coping mechanisms. Using…

  12. Word wheels

    CERN Document Server

    Clark, Kathryn

    2013-01-01

    Targeting the specific problems learners have with language structure, these multi-sensory exercises appeal to all age groups including adults. Exercises use sight, sound and touch and are also suitable for English as an Additional Lanaguage and Basic Skills students.Word Wheels includes off-the-shelf resources including lesson plans and photocopiable worksheets, an interactive CD with practice exercises, and support material for the busy teacher or non-specialist staff, as well as homework activities.

  13. Analysis of traversable pits model to make intelligent wheeled vehicles

    Directory of Open Access Journals (Sweden)

    F. Abbasi

    2017-11-01

    Full Text Available In this paper, the issue of passing wheeled vehicles from pits is discussed. The issue is modeled by defining the limits of passing wheeled vehicles. The proposed model has been studied based on changes in the effective parameters. Finally, in order to describe the problem, the proposed model has been solved for wheeled vehicles based on the effective parameters by using one of the numerical methods.

  14. Fluid Mechanics of a High Performance Racing Bicycle Wheel

    Science.gov (United States)

    Mercat, Jean-Pierre; Cretoux, Brieuc; Huat, Francois-Xavier; Nordey, Benoit; Renaud, Maxime; Noca, Flavio

    2013-11-01

    In 2012, MAVIC released the most aerodynamic bicycle wheel on the market, the CXR 80. The french company MAVIC has been a world leader for many decades in the manufacturing of bicycle wheels for competitive events such as the Olympic Games and the Tour de France. Since 2010, MAVIC has been in a research partnership with the University of Applied Sciences in Geneva, Switzerland, for the aerodynamic development of bicycle wheels. While most of the development up to date has been performed in a classical wind tunnel, recent work has been conducted in an unusual setting, a hydrodynamic towing tank, in order to achieve low levels of turbulence and facilitate quantitative flow visualization (PIV). After a short introduction on the aerodynamics of bicycle wheels, preliminary fluid mechanics results based on this novel setup will be presented.

  15. FxLMS Method for Suppressing In-Wheel Switched Reluctance Motor Vertical Force Based on Vehicle Active Suspension System

    Directory of Open Access Journals (Sweden)

    Yan-yang Wang

    2014-01-01

    Full Text Available The vibration of SRM obtains less attention for in-wheel motor applications according to the present research works. In this paper, the vertical component of SRM unbalanced radial force, which is named as SRM vertical force, is taken into account in suspension performance for in-wheel motor driven electric vehicles (IWM-EV. The analysis results suggest that SRM vertical force has a great effect on suspension performance. The direct cause for this phenomenon is that SRM vertical force is directly exerted on the wheel, which will result in great variation in tyre dynamic load and the tyre will easily jump off the ground. Furthermore, the frequency of SRM vertical force is broad which covers the suspension resonance frequencies. So it is easy to arouse suspension resonance and greatly damage suspension performance. Aiming at the new problem, FxLMS (filtered-X least mean square controller is proposed to improve suspension performance. The FxLMS controller is based on active suspension system which can generate the controllable force to suppress the vibration caused by SRM vertical force. The conclusion shows that it is effective to take advantage of active suspensions to reduce the effect of SRM vertical force on suspension performance.

  16. Characterizing the Performance of the Wheel Electrostatic Spectrometer

    Science.gov (United States)

    Johansen, Michael R.; Mackey, P. J.; Holbert, E.; Calle, C. I.; Clements, J. S.

    2013-01-01

    Insulators need to be discharged after each wheel revolution. Sensor responses repeatable within one standard deviation in the noise of the signal. Insulators may not need to be cleaned after each revolution. Parent Technology- Mars Environmental Compatibility Assessment/Electrometer Electrostatic sensors with dissimilar cover insulators Protruding insulators tribocharge against regolith simulant Developed for use on the scoop for the 2001 Mars Odyssey lander Wheel Electrostatic Spectrometer Embedded electrostatic sensors in prototype Martian rover wheel If successful, this technology will enable constant electrostatic testing on Mars Air ionizing fan used to neutralize the surface charge on cover insulators . WES rolled on JSClA lunar simulant Control experiment -Static elimination not conducted between trials -Capacitor discharged after each experiment Charge neutralization experiment -Static elimination conducted between trials -Capacitor discharged after each experiment. Air ionizing fan used on insulators after each wheel revolution Capacitor discharged after each trial Care was taken to roll WES with same speed/pressure Error bars represent one standard deviation in the noise of e ach sensor

  17. The Development of Lightweight Commercial Vehicle Wheels Using Microalloying Steel

    Science.gov (United States)

    Lu, Hongzhou; Zhang, Lilong; Wang, Jiegong; Xuan, Zhaozhi; Liu, Xiandong; Guo, Aimin; Wang, Wenjun; Lu, Guimin

    Lightweight wheels can reduce weight about 100kg for commercial vehicles, and it can save energy and reduce emission, what's more, it can enhance the profits for logistics companies. The development of lightweight commercial vehicle wheels is achieved by the development of new steel for rim, the process optimization of flash butt welding, and structure optimization by finite element methods. Niobium micro-alloying technology can improve hole expansion rate, weldability and fatigue performance of wheel steel, and based on Niobium micro-alloying technology, a special wheel steel has been studied whose microstructure are Ferrite and Bainite, with high formability and high fatigue performance, and stable mechanical properties. The content of Nb in this new steel is 0.025% and the hole expansion rate is ≥ 100%. At the same time, welding parameters including electric upsetting time, upset allowance, upsetting pressure and flash allowance are optimized, and by CAE analysis, an optimized structure has been attained. As a results, the weight of 22.5in×8.25in wheel is up to 31.5kg, which is most lightweight comparing the same size wheels. And its functions including bending fatigue performance and radial fatigue performance meet the application requirements of truck makers and logistics companies.

  18. Four-wheeled walker related injuries in older adults in the Netherlands.

    Science.gov (United States)

    van Riel, K M M; Hartholt, K A; Panneman, M J M; Patka, P; van Beeck, E F; van der Cammen, T J M

    2014-02-01

    With ageing populations worldwide, mobility devices are used more than ever. In the current literature there is no consensus whether the available mobility devices safely improve the mobility of their users. Also, evidence is lacking concerning the risks and types of injuries sustained while using a four-wheeled walker. To assess injury risks and injury patterns in older adults (≥65 years) who presented at Emergency Departments (ED) in the Netherlands with an injury due to using a four-wheeled walker. In this study, the Dutch Injury Surveillance System was used to obtain a national representative sample of annual ED visits in the Netherlands in the adult population (≥65 years) sustaining an injury while using a four-wheeled walker. The numbers of four-wheeled walker users in the Netherlands were obtained from the national insurance board. The numbers of ED visits were divided by the numbers of four-wheeled walker users to calculate age- and sex-specific injury risks. Annually 1869 older adults visited an ED after sustaining an injury while using a four-wheeled walker. Falls were the main cause of injury (96%). The injury risk was 3.1 per 100 users of four-wheeled walkers. Women (3.5 per 100 users) had a higher risk than men (2.0 per 100 users). Injury risk was the highest in women aged 85 years and older (6.2 per 100 users). The majority of injuries were fractures (60%) with hip fracture (25%) being the most common injury. Nearly half of all four-wheeled walker related injuries required hospitalisation, mostly due to hip fractures. Healthcare costs per injury were approximately €12 000. This study presents evidence that older adults experiencing a fall while using a four-wheeled walker are at high risk to suffer severe injuries.

  19. True or False Customer Engagement Behaviour

    DEFF Research Database (Denmark)

    Haurum, Helle; Beckmann, Suzanne C.

    2014-01-01

    Customers’ engagement behaviours are considered an important source of value to the company. So far, the discussion has mainly been conceptual and focused on the company’s perspective. By adopting the customer’s perspective we investigated how customers perceive their service relationship...... encounters with a company, using in-depth interviews. We found the following key factors driving and explaining customers’ engagement behaviours: (1) transactions matter and inconsistent engagement behaviours are a reality, (2) mundane products and services are still highly relevant for customers, and (3......) different degrees of customer experience alignment with services and products exist. Moreover, the distinction between true and false engagement behaviours we suggest indeed is relevant and we could establish their mediating capabilities....

  20. Cell Phone Use While Driving: Prospective Association with Emerging Adult Use.

    Science.gov (United States)

    Trivedi, Neha; Haynie, Denise; Bible, Joe; Liu, Danping; Simons-Morton, Bruce

    2017-09-01

    Secondary task engagement such as cell phone use while driving is a common behavior among adolescents and emerging adults. Texting and other distracting cell phone use in this population contributes to the high rate of fatal car crashes. Peer engagement in similar risky driving behaviors, such as texting, could socially influence driver phone use behavior. The present study investigates the prospective association between peer and emerging adult texting while driving the first year after high school. Surveys were conducted with a national sample of emerging adults and their nominated peers. Binomial logistic regression analyses, adjusting for gender, race/ethnicity, parental education, and family affluence, showed that participants (n=212) with peers (n=675) who reported frequently texting while driving, were significantly more likely to text while driving the following year (odds ratio, 3.01; 95% CI, 1.19-7.59; P=0.05). The findings are consistent with the idea that peer texting behavior influences the prevalence of texting while driving among emerging adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Enhanced voluntary wheel running in GPRC6A receptor knockout mice

    DEFF Research Database (Denmark)

    Clemmensen, Christoffer; Pehmøller, Christian; Klein, Anders B

    2013-01-01

    to voluntary wheel running and forced treadmill exercise. Moreover, we assessed energy expenditure in the basal state, and evaluated the effects of wheel running on food intake, body composition, and a range of exercise-induced central and peripheral biomarkers. We found that adaptation to voluntary wheel...... running is affected by GPRC6A, as ablation of the receptor significantly enhances wheel running in KO relative to WT mice. Both genotypes responded to voluntary exercise by increasing food intake and improving body composition to a similar degree. In conclusion, these data demonstrate that the GPRC6A...

  2. Wheel running decreases palatable diet preference in Sprague-Dawley rats

    OpenAIRE

    Moody, Laura; Liang, Joy; Choi, Pique P.; Moran, Timothy H.; Liang, Nu-Chu

    2015-01-01

    Physical activity has beneficial effects on not only improving some disease conditions but also by preventing the development of multiple disorders. Experiments in this study examined the effects of wheel running on intakes of chow and palatable diet e.g. high fat (HF) or high sucrose (HS) diet in male and female Sprague Dawley rats. Experiment 1 demonstrated that acute wheel running results in robust HF or HS diet avoidance in male rats. Although female rats with running wheel...

  3. Multi-scale Fatigue Damage Life Assessment of Railroad Wheels

    Science.gov (United States)

    2018-01-01

    This study focused on the presence of a crack in the railway wheels subsurface and how it affects the wheels fatigue life. A 3-D FE-model was constructed to simulate the stress/strain fields that take place under the rolling contact of railway ...

  4. DESIGN OF BACKWARD SWEPT TURBINE WHEEL FOR CRYOGENIC TURBOEXPANDER

    Directory of Open Access Journals (Sweden)

    BALAJI K. CHOUDHURY

    2014-08-01

    Full Text Available With support from the Department of Atomic Energy, our institute has initiated a programme on development and study of a low capacity (20 liters/hr. turboexpander based Nitrogen liquefier. Hence a process design was carried out and a turboexpander was designed to meet the requirement of the liquefier. The turboexpander is used for lowering the temperature of the process gas (Nitrogen by the isenthalpic expansion. The efficiency of the turboexpander mainly depends on the specific speed and specific diameter of the turbine wheel. The paper explains a general methodology for the design of any type of turbine wheel (radial, backward swept and forward swept for any pressure ratio with different process gases. The design of turbine wheel includes the determination of dimensions, blade profile and velocity triangles at inlet and outlet of the turbine wheel. Generally radial turbine wheels are used but in this case to achieve the high efficiency at desired speed, backward curved blades are used to maintain the Mach number of the process gas at the nozzle exit, close to unity. If the velocity of fluid exceeds the speed of sound, the flow gets choked leading to the creation of shock waves and flow at the exit of the nozzle will be non-isentropic.

  5. Experimental analysis and regression prediction of desiccant wheel behavior in high temperature heat pump and desiccant wheel air-conditioning system

    DEFF Research Database (Denmark)

    Sheng, Ying; Zhang, Yufeng; Sun, Yuexia

    2014-01-01

    The objectives of this study are to evaluate the performance of desiccant wheel (DW) in the running system and obtain the useful data for practical application. The combined influences of multiple variables on the performance of desiccant wheel are investigated based on evaluating the indexes...... of moisture removal capacity, dehumidification effectiveness, dehumidification coefficient of performance and sensible energy ratio. The results show that higher effect on the dehumidification is due to the regeneration temperature and outdoor air humidity ratio rather than the outdoor air temperature...... and the ratio between regeneration and process air flow rates. A simple method based on multiple linear regression theory for predicting the performance of the wheel has been proposed. The predicted values and the experimental data are compared and good agreements are obtained. Regression models are established...

  6. A comparison of two types of running wheel in terms of mouse preference, health, and welfare.

    Science.gov (United States)

    Walker, Michael; Mason, Georgia

    2018-07-01

    Voluntary wheel running occurs in mice of all strains, sexes, and ages. Mice find voluntary wheel running rewarding, and it leads to numerous health benefits. For this reason wheels are used both to enhance welfare and to create models of exercise. However, many designs of running wheel are used. This makes between-study comparisons difficult, as this variability could potentially affect the amount, pattern, and/or intensity of running behaviour, and thence the wheels' effects on welfare and exercise-related changes in anatomy and physiology. This study therefore evaluated two commercially available models, chosen because safe for group-housed mice: Bio Serv®'s "fast-trac" wheel combo and Ware Manufacturing Inc.'s stainless steel mesh 5″ upright wheel. Working with a total of three hundred and fifty one female C57BL/6, DBA/2 and BALB/c mice, we assessed these wheels' relative utilization by mice when access was free; the strength of motivation for each wheel-type when access required crossing an electrified grid; and the impact each wheel had on mouse well-being (inferred from acoustic startle responses and neophobia) and exercise-related anatomical changes (BMI; heart and hind limb masses). Mice ran more on the "fast-trac" wheel regardless of whether both wheel-types were available at once, or only if one was present. In terms of motivation, subjects required to work to access a single wheel worked equally hard for both wheel-types (even if locked and thus not useable for running), but if provided with one working wheel for free and the other type of wheel (again unlocked) accessible via crossing the electrified grid, the "fast-trac" wheel emerged as more motivating, as the Maximum Price Paid for the Ware metal wheel was lower than that paid for the "fast-trac" plastic wheel, at least for C57BL/6s and DBA/2s. No deleterious consequences were noted with either wheel in terms of health and welfare, but only mice with plastic wheels developed significantly larger

  7. Integration of uniform design and quantum-behaved particle swarm optimization to the robust design for a railway vehicle suspension system under different wheel conicities and wheel rolling radii

    Science.gov (United States)

    Cheng, Yung-Chang; Lee, Cheng-Kang

    2017-10-01

    This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspension system. Based on the new nonlinear creep model derived from combining Hertz contact theory, Kalker's linear theory and a heuristic nonlinear creep model, the modeling and dynamic analysis of a 24 degree-of-freedom railway vehicle system were investigated. The Lyapunov indirect method was used to examine the effects of suspension parameters, wheel conicities and wheel rolling radii on critical hunting speeds. Generally, the critical hunting speeds of a vehicle system resulting from worn wheels with different wheel rolling radii are lower than those of a vehicle system having original wheels without different wheel rolling radii. Because of worn wheels, the critical hunting speed of a running railway vehicle substantially declines over the long term. For safety reasons, it is necessary to design the suspension system parameters to increase the robustness of the system and decrease the sensitive of wheel noises. By applying UD and QPSO, the nominal-the-best signal-to-noise ratio of the system was increased from -48.17 to -34.05 dB. The rate of improvement was 29.31%. This study has demonstrated that the integration of UD and QPSO can successfully reveal the optimal solution of suspension parameters for solving the robust design problem of a railway vehicle suspension system.

  8. Cross-stream ejection in the inter-wheel region of aircraft landing gears

    Science.gov (United States)

    McCarthy, Philip; Ekmekci, Alis

    2014-11-01

    The reduction of aircraft noise is an important challenge currently faced by aircraft manufacturers. During approach and landing, the landing gears contribute a significant proportion of the aircraft generated noise. It is therefore critical that the key noise sources be identified and understood in order for effective mitigation methods to be developed. For a simplified two-wheel nose landing gear, a strong cross stream flow ejection phenomena has been observed to occur in the inter-wheel region in presence of wheel wells. The location and orientation of these flow ejections causes highly unsteady, three dimensional flow between the wheels that may impinge on other landing gear components, thereby potentially acting as a significant noise generator. The effects of changing the inter-wheel geometry (inter-wheel spacing, the wheel well depth and main strut geometry) upon the cross-stream ejection behaviour has been experimentally investigated using both qualitative flow visualisation and quantitative PIV techniques. A summary of the key results will be presented for the three main geometrical parameters under examination and the application of these findings to real life landing gears will be discussed. Thanks to Messier-Bugatti-Dowty and NSERC for their support for this project.

  9. Mission Analysis and Orbit Control of Interferometric Wheel Formation Flying

    Science.gov (United States)

    Fourcade, J.

    Flying satellite in formation requires maintaining the specific relative geometry of the spacecraft with high precision. This requirement raises new problem of orbit control. This paper presents the results of the mission analysis of a low Earth observation system, the interferometric wheel, patented by CNES. This wheel is made up of three receiving spacecraft, which follow an emitting Earth observation radar satellite. The first part of this paper presents trades off which were performed to choose orbital elements of the formation flying which fulfils all constraints. The second part presents orbit positioning strategies including reconfiguration of the wheel to change its size. The last part describes the station keeping of the formation. Two kinds of constraints are imposed by the interferometric system : a constraint on the distance between the wheel and the radar satellite, and constraints on the distance between the wheel satellites. The first constraint is fulfilled with a classical chemical station keeping strategy. The second one is fulfilled using pure passive actuators. Due to the high stability of the relative eccentricity of the formation, only the relative semi major axis had to be controlled. Differential drag due to differential attitude motion was used to control relative altitude. An autonomous orbit controller was developed and tested. The final accuracy is a relative station keeping better than few meters for a wheel size of one kilometer.

  10. Exploring a Middle Ground Engagement with Students in a Social Learning Environment.

    Science.gov (United States)

    Smith, Anne M. J.; Campbell, Sonya

    2012-01-01

    The twenty first century student demands more from universities in terms of engagement that is flexible, accessible and immediate. This means universities revisiting their engagement agenda at a time when financial constraints can least afford expensive technologies and resource dependent engagement solutions. Solutions are likely to be varied…

  11. Research on fatigue driving pre-warning system based on multi-information fusion

    Science.gov (United States)

    Zhao, Xuyang; Ye, Wenwu

    2018-05-01

    With the development of science and technology, transportation network has grown faster. But at the same time, the quantity of traffic accidents due to fatigue driving grows faster as well. In the meantime, fatigue driving has been one of the main causes of traffic accidents. Therefore, it is indispensable for us to study the detection of fatigue driving to help to driving safety. There are numerous approaches in discrimination method. Each type of method has its reasonable theoretical basis, but the disadvantages of traditional fatigue driving detection methods have been more and more obvious since we study the traditional physiology and psychological features of fatigue drivers. So we set up a new system based on multi-information fusion and pattern recognition theory. In the paper, the fatigue driving pre-warning system discriminates fatigue by analyzing the characteristic parameters, the parameters derived from the steering wheel angle, the driver's power of gripping and the heart rate. And the data analysis system is established based on fuzzy C-means clustering theory. Finally, KNN classifier is used to establish the relation between feature indexes and fatigue degree. It is verified that the system has the better accuracy, agility and robustness according to our confirmatory experiment.

  12. Space shuttle wheels and brakes

    Science.gov (United States)

    Carsley, R. B.

    1985-01-01

    The Space Shuttle Orbiter wheels were subjected to a combination of tests which are different than any previously conducted in the aerospace industry. The major testing difference is the computer generated dynamic landing profiles used during the certification process which subjected the wheels and tires to simulated landing loading conditions. The orbiter brakes use a unique combination of carbon composite linings and beryllium heat sink to minimize weight. The development of a new lining retention method was necessary in order to withstand the high temperature generated during the braking roll. As with many programs, the volume into which this hardware had to fit was established early in the program, with no provisions made for growth to offset the continuously increasing predicted orbiter landing weight.

  13. Procedure and applications of combined wheel/rail roughness measurement

    NARCIS (Netherlands)

    Dittrich, M.G.

    2009-01-01

    Wheel-rail roughness is known to be the main excitation source of railway rolling noise. Besides the already standardised method for direct roughness measurement, it is also possible to measure combined wheel-rail roughness from vertical railhead vibration during a train pass-by. This is a different

  14. Nesting behavior of house mice (Mus domesticus) selected for increased wheel-running activity.

    Science.gov (United States)

    Carter, P A; Swallow, J G; Davis, S J; Garland, T

    2000-03-01

    Nest building was measured in "active" (housed with access to running wheels) and "sedentary" (without wheel access) mice (Mus domesticus) from four replicate lines selected for 10 generations for high voluntary wheel-running behavior, and from four randombred control lines. Based on previous studies of mice bidirectionally selected for thermoregulatory nest building, it was hypothesized that nest building would show a negative correlated response to selection on wheel-running. Such a response could constrain the evolution of high voluntary activity because nesting has also been shown to be positively genetically correlated with successful production of weaned pups. With wheel access, selected mice of both sexes built significantly smaller nests than did control mice. Without wheel access, selected females also built significantly smaller nests than did control females, but only when body mass was excluded from the statistical model, suggesting that body mass mediated this correlated response to selection. Total distance run and mean running speed on wheels was significantly higher in selected mice than in controls, but no differences in amount of time spent running were measured, indicating a complex cause of the response of nesting to selection for voluntary wheel running.

  15. Design of wheel-type walking-assist device

    International Nuclear Information System (INIS)

    Jung, Seung Ho; Kim, Seung Ho; Kim, Chang Hoi; Seo, Yong Chil; Jung, Kyung Min; Lee, Sung Uk

    2006-03-01

    In this research, a outdoor wheel-type walking-assist device is developed to help an elder having a poor muscular strength at legs for walking, sitting and standing up easily at outdoors, and also for going and downing stairs. In conceptually designing, the environments of an elder's activity, the size of an elder's body and a necessary function of helping an elder are considered. This device has 4 wheels for stability. When an elder walks in incline plane with the proposed device, a rear-wing is rotated to keep the supporting device horizontal, regardless of an angle of inclination. A height-controlling device, which can control the height of the supporting device for adjusting an elder's height, is varied vertically to help an elder to sit and stand-up easily. Moreover, a outdoor wheel-type walking-assist device is conceptually designed and is made. In order to design it, the preview research is investigated firstly. On the basis of the proposed walking-assist device, the outdoor walking-assist device is designed and made. The outdoor wheel-type walking-assist device can go and down stairs automatically. This device go up and down the stair of having maximum 20cm height and an angle of 25 degrees with maximum 4 sec/stairs speed, and move at flatland with 60cm/sec speed

  16. Collaborative engagement experiment (CEE)

    Science.gov (United States)

    Wade, Robert L.; Reames, Joseph M.

    2005-05-01

    Unmanned ground and air systems operating in collaboration have the potential to provide future Joint Forces a significant capability for operations in complex terrain. Ground and air collaborative engagements potentially offer force conservation, perform timely acquisition and dissemination of essential combat information, and can eliminate high value and time critical targets. These engagements can also add considerably to force survivability by reducing soldier and equipment exposure during critical operations. The Office of the Secretary of Defense, Joint Robotics Program (JRP) sponsored Collaborative Engagement Experiment (CEE) is a consolidation of separate Air Force, Army and Navy collaborative efforts to provide a Joint capability. The Air Force Research Laboratory (AFRL), Material and Manufacturing Directorate, Aerospace Expeditionary Force Division, Force Protection Branch (AFRLMLQF), The Army Aviation and Missile Research, Development and Engineering Center (AMRDEC) Joint Technology Center (JTC)/Systems Integration Laboratory (SIL), and the Space and Naval Warfare Systems Center-San Diego (SSC San Diego) are conducting technical research and proof of principle for an envisioned operational concept for extended range, three dimensional, collaborative operations between unmanned systems, with enhanced situational awareness for lethal operations in complex terrain. This program will assess information requirements and conduct experiments to identify and resolve technical risks for collaborative engagements using Unmanned Ground Vehicles (UGVs) and Unmanned Aerial Vehicles (UAVs). It will research, develop and physically integrate multiple unmanned systems and conduct live collaborative experiments. Modeling and Simulation systems will be upgraded to reflect engineering fidelity levels to greater understand technical challenges to operate as a team. This paper will provide an update of a multi-year program and will concentrate primarily on the JTC

  17. Opportunity's View After Long Drive on Sol 1770

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings just after driving 104 meters (341 feet) on the 1,770th Martian day, or sol, of Opportunity's surface mission (January 15, 2009). Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Prior to the Sol 1770 drive, Opportunity had driven less than a meter since Sol 1713 (November 17, 2008), while it used the tools on its robotic arm first to examine a meteorite called 'Santorini' during weeks of restricted communication while the sun was nearly in line between Mars and Earth, then to examine bedrock and soil targets near Santorini. The rover's position after the Sol 1770 drive was about 1.1 kilometer (two-thirds of a mile) south southwest of Victoria Crater. Cumulative odometry was 13.72 kilometers (8.53 miles) since landing in January 2004, including 1.94 kilometers (1.21 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a cylindrical projection with geometric seam correction.

  18. Nonlinear dynamics modeling and simulation of two-wheeled self-balancing vehicle

    Directory of Open Access Journals (Sweden)

    Yunping Liu

    2016-11-01

    Full Text Available Two-wheeled self-balancing vehicle system is a kind of naturally unstable underactuated system with high-rank unstable multivariable strongly coupling complicated dynamic nonlinear property. Nonlinear dynamics modeling and simulation, as a basis of two-wheeled self-balancing vehicle dynamics research, has the guiding effect for system design of the project demonstration and design phase. Dynamics model of the two-wheeled self-balancing vehicle is established by importing a TSi ProPac package to the Mathematica software (version 8.0, which analyzes the stability and calculates the Lyapunov exponents of the system. The relationship between external force and stability of the system is analyzed by the phase trajectory. Proportional–integral–derivative control is added to the system in order to improve the stability of the two-wheeled self-balancing vehicle. From the research, Lyapunov exponent can be used to research the stability of hyperchaos system. The stability of the two-wheeled self-balancing vehicle is better by inputting the proportional–integral–derivative control. The Lyapunov exponent and phase trajectory can help us analyze the stability of a system better and lay the foundation for the analysis and control of the two-wheeled self-balancing vehicle system.

  19. Design Optimization of Heat Wheels for Energy Recovery in HVAC Systems

    Directory of Open Access Journals (Sweden)

    Stefano De Antonellis

    2014-11-01

    Full Text Available Air to air heat exchangers play a crucial role in mechanical ventilation equipment, due to the potential primary energy savings both in case of refurbishment of existing buildings or in case of new ones. In particular, interest in heat wheels is increasing due to their low pressure drop and high effectiveness. In this paper a detailed optimization of design parameters of heat wheels is performed in order to maximize sensible effectiveness and to minimize pressure drop. The analysis is carried out through a one dimensional lumped parameters heat wheel model, which solves heat and mass transfer equations, and through appropriate correlations to estimate pressure drop. Simulation results have been compared with experimental data of a heat wheel tested in specific facilities, and good agreement is attained. The device optimization is performed through the variation of main design parameters, such as heat wheel length, channel base, height and thickness and for different operating conditions, namely the air face velocity and the revolution speed. It is shown that the best configurations are achieved with small channel thickness and, depending on the required sensible effectiveness, with appropriate values of wheel length and channel base and height.

  20. 3D dynamic modeling of spherical wheeled self-balancing mobile robot

    OpenAIRE

    İnal, Ali Nail

    2012-01-01

    Ankara : The Department of Electrical and Electronics Engineering and the Graduate School of Engineering and Science of Bilkent University, 2012. Thesis (Master's) -- Bilkent University, 2012. Includes bibliographical references. In recent years, dynamically stable platforms that move on spherical wheels, also known as BallBots, gained popularity in the robotics literature as an alternative locomotion method to statically stable wheeled mobile robots. In contrast to wheeled ...

  1. Voluntary resistance running wheel activity pattern and skeletal muscle growth in rats.

    Science.gov (United States)

    Legerlotz, Kirsten; Elliott, Bradley; Guillemin, Bernard; Smith, Heather K

    2008-06-01

    The aims of this study were to characterize the pattern of voluntary activity of young rats in response to resistance loading on running wheels and to determine the effects of the activity on the growth of six limb skeletal muscles. Male Sprague-Dawley rats (4 weeks old) were housed individually with a resistance running wheel (R-RUN, n = 7) or a conventional free-spinning running wheel (F-RUN, n = 6) or without a wheel, as non-running control animals (CON, n = 6). The torque required to move the wheel in the R-RUN group was progressively increased, and the activity (velocity, distance and duration of each bout) of the two running wheel groups was recorded continuously for 45 days. The R-RUN group performed many more, shorter and faster bouts of running than the F-RUN group, yet the mean daily distance was not different between the F-RUN (1.3 +/- 0.2 km) and R-RUN group (1.4 +/- 0.6 km). Only the R-RUN resulted in a significantly (P RUN and R-RUN led to a significantly greater wet mass relative to increase in body mass and muscle fibre cross-sectional area in the soleus muscle compared with CON. We conclude that the pattern of voluntary activity on a resistance running wheel differs from that on a free-spinning running wheel and provides a suitable model to induce physiological muscle hypertrophy in rats.

  2. Simulation and Measurement of Wheel on Rail Fatigue and Wear

    OpenAIRE

    Dirks, Babette

    2015-01-01

    The life of railway wheels and rails has been decreasing in recent years. This is mainly caused by more traffic and running at higher vehicle speed. A higher speed usually generates higher forces, unless compensated by improved track and vehicle designs, in the wheel-rail contact, resulting in more wear and rolling contact fatigue (RCF) damage to the wheels and rails. As recently as 15 years ago, RCF was not recognised as a serious problem. Nowadays it is a serious problem in many countries a...

  3. Implementation of safety driving system using e-health and telematics technology.

    Science.gov (United States)

    Lee, Youngbum; Lee, Myoungho

    2008-08-01

    This research aimed to develop a safety driving system using e-health and telematics technology. Biosignal sensors were installed in an automobile to check the driver's health status with an automatic diagnosis system providing health information to the driver. Measured data were sent to the e-health center through a telematics device, and a medical doctor analyzed these data, sending diagnosis and prescription information to the driver. This system recognizes the driver's sleeping, drinking impairment, excitability, and fatigue using biosensors. The system initially provides alerts in the automobile. It also controls the driving environment in the car, searches for a highway service area using Global Positioning System (GPS), and provides additional information for safety driving. If a car accident has occurred, it makes an emergency call to the nearest hospital, emergency center, and insurance company. A conceptual and prototype model for an imbedded system is presented with initial data for driver condition. Such a system could prevent car accidents caused by drivers driving while intoxicated and falling asleep at the wheel using the driver's biosignals measured by biosensors. The system can provide various e-health services using a telematics system to enhance the technical compatibility of the automobile.

  4. Considerations on the use of elastic wheels to the urban transport vehicles

    Science.gov (United States)

    Sebesan, Ioan; Arsene, Sorin; Manea, Ion

    2018-03-01

    To minimize dynamic wheel-rail interaction efforts a condition is that the unassembled mass of the vehicle is as small as possible. The elastic wheel by its construction fulfills these conditions - she has interposed between the crown and the body of the wheel, the elastic rubber elements. In this way, it can be considered that the unsupported mass is represented only by the mass of the wheel crown. Additionally, this elasticity also has a reduction effect on rolling noise. This feature makes it suitable for use on urban transport vehicles.

  5. Naloxone attenuates the conditioned place preference induced by wheel running in rats.

    Science.gov (United States)

    Lett, B T; Grant, V L; Koh, M T

    2001-02-01

    Pairings, during which an episode of wheel running is followed by confinement in a distinctive place, produce conditioned place preference (CPP) in rats. This finding indicates that wheel running has a rewarding effect that outlasts the activity itself. In two similar experiments, we tested the hypothesis that this rewarding effect of wheel running is mediated by endogenous opioids. During a paired trial, the rats in the naloxone group were first allowed to wheel run for 2 h, then injected with naloxone (0.5 or 0.1 mg/kg in Experiments 1 and 2, respectively), and 10 min later placed in a distinctive chamber. During an unpaired trial, these rats were confined in an adjoining chamber without wheel running. Naloxone was injected before placement in both chambers, so that if naloxone-induced conditioned place aversion occurred, it would have counteracting effects on performance during the preference test. The rats in the saline group were similarly treated, except that saline was injected instead of naloxone. CPP occurred in the saline group, but not in the naloxone group. Thus, naloxone attenuated the CPP induced by wheel running. This finding supports the hypothesis that the rewarding effect of wheel running is mediated by endogenous opioids.

  6. Damages and resource of locomotive wheels used under the north operating conditions

    Directory of Open Access Journals (Sweden)

    A. V. Grigorev

    2014-01-01

    Full Text Available In operating railway equipment, in particular the elements, such as a wheel and a rail there is damage accumulation of any kind, causing a premature equipment failure. Thus, an analysis of the mechanisms and modeling of damage accumulation and fracture both on the surface and in the bulk material remain a challenge.Data on the defective wheel sets to be subjected to facing has been collected and analyzed to assess the locomotive wheel sets damage of the locomotive fleet company of AK «Yakutia Railways», city of Aldan, The Republic of Sakha (Yakutia. For this purpose, three main locomotives have been examined.The object of research carried out in this paper, is a locomotive wheels tire, which is subjected to cyclic impact (dynamic loads during operation. In this regard, the need arises to determine both the strength of material in response to such shock loads and the quantitative calculation of damage accumulated therein.The accumulated fatigue damage has been attributed to one radial cross section of the wheel coming into contact with the rail once per revolution of the wheel. Consequently, in one revolution a wheel is under one loading cycle. As stated, the average mileage of locomotives to have the unacceptable damages formed on the tread surface is 12 thousand km.Test results establish that along with the high-cycle loading the shock-contact action on rail joints significantly affects the accumulation of damage in the locomotive wheels tire. The number of cycles to failure due to the formation of unacceptable damage in the locomotive wheels tire is N = 2,4×106 and 6×105 cycles, respectively, for fatigue and shock-contact loading.In general, we can say that the problem of higher intensity to form the surface damage is directly related to the operation of the locomotive wheel tire under abnormally low climatic temperatures. With decreasing ambient temperature, this element material rapidly looses its plastic properties, thereby accelerating

  7. The Quality and Accuracy of Mobile Apps to Prevent Driving After Drinking Alcohol.

    Science.gov (United States)

    Wilson, Hollie; Stoyanov, Stoyan R; Gandabhai, Shailen; Baldwin, Alexander

    2016-08-08

    Driving after the consumption of alcohol represents a significant problem globally. Individual prevention countermeasures such as personalized mobile app aimed at preventing such behavior are widespread, but there is little research on their accuracy and evidence base. There has been no known assessment investigating the quality of such apps. This study aimed to determine the quality and accuracy of apps for drink driving prevention by conducting a review and evaluation of relevant mobile apps. A systematic app search was conducted following PRISMA guidelines. App quality was assessed using the Mobile App Rating Scale (MARS). Apps providing blood alcohol calculators (hereafter "calculators") were reviewed against current alcohol advice for accuracy. A total of 58 apps (30 iOS and 28 Android) met inclusion criteria and were included in the final analysis. Drink driving prevention apps had significantly lower engagement and overall quality scores than alcohol management apps. Most calculators provided conservative blood alcohol content (BAC) time until sober calculations. None of the apps had been evaluated to determine their efficacy in changing either drinking or driving behaviors. This novel study demonstrates that most drink driving prevention apps are not engaging and lack accuracy. They could be improved by increasing engagement features, such as gamification. Further research should examine the context and motivations for using apps to prevent driving after drinking in at-risk populations. Development of drink driving prevention apps should incorporate evidence-based information and guidance, lacking in current apps.

  8. Design and Assessment of a Machine Vision System for Automatic Vehicle Wheel Alignment

    Directory of Open Access Journals (Sweden)

    Rocco Furferi

    2013-05-01

    Full Text Available Abstract Wheel alignment, consisting of properly checking the wheel characteristic angles against vehicle manufacturers' specifications, is a crucial task in the automotive field since it prevents irregular tyre wear and affects vehicle handling and safety. In recent years, systems based on Machine Vision have been widely studied in order to automatically detect wheels' characteristic angles. In order to overcome the limitations of existing methodologies, due to measurement equipment being mounted onto the wheels, the present work deals with design and assessment of a 3D machine vision-based system for the contactless reconstruction of vehicle wheel geometry, with particular reference to characteristic planes. Such planes, properly referred to as a global coordinate system, are used for determining wheel angles. The effectiveness of the proposed method was tested against a set of measurements carried out using a commercial 3D scanner; the absolute average error in measuring toe and camber angles with the machine vision system resulted in full compatibility with the expected accuracy of wheel alignment systems.

  9. Wheels lining up for ATLAS

    CERN Multimedia

    2003-01-01

    On 30 October, the mechanics test assembly of the central barrel of the ATLAS tile hadronic calorimeter was completed in building 185. It is the second wheel for the Tilecal completely assembled this year.

  10. Modeling Driving Performance Using In-Vehicle Speech Data From a Naturalistic Driving Study.

    Science.gov (United States)

    Kuo, Jonny; Charlton, Judith L; Koppel, Sjaan; Rudin-Brown, Christina M; Cross, Suzanne

    2016-09-01

    We aimed to (a) describe the development and application of an automated approach for processing in-vehicle speech data from a naturalistic driving study (NDS), (b) examine the influence of child passenger presence on driving performance, and (c) model this relationship using in-vehicle speech data. Parent drivers frequently engage in child-related secondary behaviors, but the impact on driving performance is unknown. Applying automated speech-processing techniques to NDS audio data would facilitate the analysis of in-vehicle driver-child interactions and their influence on driving performance. Speech activity detection and speaker diarization algorithms were applied to audio data from a Melbourne-based NDS involving 42 families. Multilevel models were developed to evaluate the effect of speech activity and the presence of child passengers on driving performance. Speech activity was significantly associated with velocity and steering angle variability. Child passenger presence alone was not associated with changes in driving performance. However, speech activity in the presence of two child passengers was associated with the most variability in driving performance. The effects of in-vehicle speech on driving performance in the presence of child passengers appear to be heterogeneous, and multiple factors may need to be considered in evaluating their impact. This goal can potentially be achieved within large-scale NDS through the automated processing of observational data, including speech. Speech-processing algorithms enable new perspectives on driving performance to be gained from existing NDS data, and variables that were once labor-intensive to process can be readily utilized in future research. © 2016, Human Factors and Ergonomics Society.

  11. Advanced, Analytic, Automated (AAA) Measurement of Engagement during Learning

    Science.gov (United States)

    D'Mello, Sidney; Dieterle, Ed; Duckworth, Angela

    2017-01-01

    It is generally acknowledged that engagement plays a critical role in learning. Unfortunately, the study of engagement has been stymied by a lack of valid and efficient measures. We introduce the advanced, analytic, and automated (AAA) approach to measure engagement at fine-grained temporal resolutions. The AAA measurement approach is grounded in…

  12. Student Engagement: Developing a Conceptual Framework and Survey Instrument

    Science.gov (United States)

    Burch, Gerald F.; Heller, Nathan A.; Burch, Jana J.; Freed, Rusty; Steed, Steve A.

    2015-01-01

    Student engagement is considered to be among the better predictors of learning, yet there is growing concern that there is no consensus on the conceptual foundation. The authors propose a conceptualization of student engagement grounded in A. W. Astin's (1984) Student Involvement Theory and W. A. Kahn's (1990) employee engagement research where…

  13. Recognition of diamond grains on surface of fine diamond grinding wheel

    Institute of Scientific and Technical Information of China (English)

    Fengwei HUO; Zhuji JIN; Renke KANG; Dongming GUO; Chun YANG

    2008-01-01

    The accurate evaluation of grinding wheel sur-face topography, which is necessary for the investigation of the grinding principle, optimism, modeling, and simu-lation of a grinding process, significantly depends on the accurate recognition of abrasive grains from the measured wheel surface. A detailed analysis of the grain size distri-bution characteristics and grain profile wavelength of the fine diamond grinding wheel used for ultra-precision grinding is presented. The requirements of the spatial sampling interval and sampling area for instruments to measure the surface topography of a diamond grinding wheel are discussed. To recognize diamond grains, digital filtering is used to eliminate the high frequency disturb-ance from the measured 3D digital surface of the grinding wheel, the geometric features of diamond grains are then extracted from the filtered 3D digital surface, and a method based on the grain profile frequency characteris-tics, diamond grain curvature, and distance between two adjacent diamond grains is proposed. A 3D surface pro-filer based on scanning white light interferometry is used to measure the 3D surface topography of a #3000 mesh resin bonded diamond grinding wheel, and the diamond grains are then recognized from the 3D digital surface. The experimental result shows that the proposed method is reasonable and effective.

  14. The Player Engagement Process

    DEFF Research Database (Denmark)

    Schoenau-Fog, Henrik

    2011-01-01

    , categories and triggers involved in this process. By applying grounded theory to the analysis of the responses, a process-oriented player engagement framework was developed and four main components consisting of objectives, activities, accomplishments and affects as well as the corresponding categories...

  15. Evaluation of the 30 Ton CHA Crane Wheel Axle Modification

    International Nuclear Information System (INIS)

    RICH, J.W.

    2002-01-01

    An existing design for eccentric bushings was utilized and updated as necessary to accommodate minor adjustment as required to correct wheel alignment on the North West Idler wheel. The design is revised to install eccentric bushings on only one end

  16. The time has come for retail wheeling

    International Nuclear Information System (INIS)

    Dahlen, D.O.; Achinger, S.K.

    1993-01-01

    Retail wheeling, the transmission and distribution of electric power for end users, fosters competition and promotes the efficient use of resources. Access to electric-utility transmission and distribution systems would establish competitive electric markets by permitting retail customers to obtain the lowest cost for energy which would meet their specific needs. Among electric utilities and their customers, the idea of allowing market forces to attract supply and set prices is a current controversy. To counter the anticompetitive effects of recent mergers in the wholesale market, the Federal Energy Regulatory Commission (FERC) has mandated open transmission access for wholesale customers. However, the FERC denied access to retail customers and qualifying facilities (QF) in both its Northeast Utilities (FERC case No. EC-90-1 90) and PacifiCorp (U.S. Circuit Court of Appeals for D.C., 89-1333) decisions. Retail wheeling will benefit both consumers and producers. The ability of large customers to purchase power from the lowest cost sources and have it transmitted to their facilities, will save American industrial and commercial customers at least $15 billion annually. The Increased efficiency resulting from competition would also reduce residential electric bills. Through retail wheeling, independent power producers can market their capacity to a greater customer base, and traditional utilities will benefit from access to other utilities markets with the more efficient utilities prospering. Retail wheeling will, therefore, reward efficient utilities and encourage inefficient utilities to improve

  17. Self-reported and observed risky driving behaviors among frequent and infrequent cell phone users.

    Science.gov (United States)

    Zhao, Nan; Reimer, Bryan; Mehler, Bruce; D'Ambrosio, Lisa A; Coughlin, Joseph F

    2013-12-01

    The apparently higher crash risk among individuals who use cell phones while driving may be due both to the direct interference of cell phone use with the driving task and tendencies to engage in risky driving behaviors independent of cell phone use. Measurements of actual highway driving performance, self-reported aberrant driving behaviors as measured by the Manchester Driver Behavior Questionnaire (DBQ), and attitudes toward speeding, passing behaviors and relative concern about being involved in a crash were assessed. Individuals who reported frequently using cell phones while driving were found to drive faster, change lanes more frequently, spend more time in the left lane, and engage in more instances of hard braking and high acceleration events. They also scored higher in self-reported driving violations on the DBQ and reported more positive attitudes toward speeding and passing than drivers who did not report using a cell phone regularly while driving. These results indicate that a greater reported frequency of cell phone use while driving is associated with a broader pattern of behaviors that are likely to increase the overall risk of crash involvement. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Wheeling and transmission system service policy in North America

    International Nuclear Information System (INIS)

    Casazza, J.A.; Schultz, A.J.; Limmer, H.D.

    1991-01-01

    This paper provides a review and discussion of the status of wheeling in the USA and Canada; the pros and cons of the new policies that are evolving and under consideration for wheeling and transmission access; specific case examples of some of the difficulties that have arisen; and the potential for new transmission technology. (author)

  19. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent.

    Directory of Open Access Journals (Sweden)

    Patricia Tachinardi

    Full Text Available Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel.

  20. Sensor set-up for wireless measurement of automotive rim and wheel parameters in laboratory conditions

    Science.gov (United States)

    Borecki, M.; Prus, P.; Korwin-Pawlowski, M. L.; Rychlik, A.; Kozubel, W.

    2017-08-01

    Modern rims and wheels are tested at the design and production stages. Tests can be performed in laboratory conditions and on the ride. In the laboratory, complex and costly equipment is used, as for example wheel balancers and impact testers. Modern wheel balancers are equipped with electronic and electro-mechanical units that enable touch-less measurement of dimensions, including precision measurement of radial and lateral wheel run-out, automatic positioning and application of the counterweights, and vehicle wheel set monitoring - tread wear, drift angles and run-out unbalance. Those tests are performed by on-wheel axis measurements with laser distance meters. The impact tester enables dropping of weights from a defined height onto a wheel. Test criteria are the loss of pressure of the tire and generation of cracks in the wheel without direct impact of the falling weights. In the present paper, a set up composed of three accelerometers, a temperature sensor and a pressure sensor is examined as the base of a wheel tester. The sensor set-up configuration, on-line diagnostic and signal transmission are discussed.

  1. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent

    Science.gov (United States)

    Tachinardi, Patricia; Tøien, Øivind; Valentinuzzi, Veronica S.; Buck, C. Loren; Oda, Gisele A.

    2015-01-01

    Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti) are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel. PMID:26460828

  2. A new solution method for wheel/rail rolling contact.

    Science.gov (United States)

    Yang, Jian; Song, Hua; Fu, Lihua; Wang, Meng; Li, Wei

    2016-01-01

    To solve the problem of wheel/rail rolling contact of nonlinear steady-state curving, a three-dimensional transient finite element (FE) model is developed by the explicit software ANSYS/LS-DYNA. To improve the solving speed and efficiency, an explicit-explicit order solution method is put forward based on analysis of the features of implicit and explicit algorithm. The solution method was first applied to calculate the pre-loading of wheel/rail rolling contact with explicit algorithm, and then the results became the initial conditions in solving the dynamic process of wheel/rail rolling contact with explicit algorithm as well. Simultaneously, the common implicit-explicit order solution method is used to solve the FE model. Results show that the explicit-explicit order solution method has faster operation speed and higher efficiency than the implicit-explicit order solution method while the solution accuracy is almost the same. Hence, the explicit-explicit order solution method is more suitable for the wheel/rail rolling contact model with large scale and high nonlinearity.

  3. Theoretical design study of the MSFC wind-wheel turbine

    Science.gov (United States)

    Frost, W.; Kessel, P. A.

    1982-01-01

    A wind wheel turbine (WWT) is studied. Evaluation of the probable performance, possible practical applications, and economic viability as compared to other conventional wind energy systems is discussed. The WWT apparatus is essentially a bladed wheel which is directly exposed to the wind on the upper half and exposed to wind through multiple ducting on the lower half. The multiple ducts consist of a forward duct (front concentrator) and two side ducts (side concentrators). The forced rotation of the wheel is then converted to power through appropriate subsystems. Test results on two simple models, a paper model and a stainless steel model, are reported. Measured values of power coefficients over wind speeds ranging from 4 to 16 m/s are given. An analytical model of a four bladed wheel is also developed. Overall design features of the wind turbine are evaluated and discussed. Turbine sizing is specified for a 5 and 25 kW machine. Suggested improvements to the original design to increase performance and performance predictions for an improved WWT design are given.

  4. Distracted driving: prevalence, problems, and prevention.

    Science.gov (United States)

    Overton, Tiffany L; Rives, Terry E; Hecht, Carrie; Shafi, Shahid; Gandhi, Rajesh R

    2015-01-01

    While the number of motor vehicle crashes has declined over the years, crashes resulting from distracted driving are increasing in the United States resulting in significant morbidity and mortality. The national public seems to be aware of the dangers associated with using technology while driving, but continues to engage in this dangerous behaviour, and may be unaware of or underestimate the impact of cell phone use on their own driving performance. Problems associated with distracted driving are not limited to novice or teenage drivers; multifaceted universal prevention efforts aimed at impacting large segments of the population may have the greatest impact. Legislation limiting drivers' cell phone use has had little impact, possibly due to low regulation and enforcement. Behaviour change programmes, improved vehicle safety, and public awareness campaigns have been developed as potential preventive efforts to reduce accidents caused by distracted drivers.

  5. Risky riding behavior on two wheels: the role of cognitive, social, and personality variables among young adolescents.

    Science.gov (United States)

    Falco, Alessandra; Piccirelli, Alessandra; Girardi, Damiano; Dal Corso, Laura; De Carlo, Nicola A

    2013-09-01

    The main objective of this study was to analyze and estimate the relations between risky riding behaviors and some personality and sociocognitive variables through structural equation modeling. We focused on two-wheel riding behavior among a sample of 1,028 Italian adolescents at their first driving experience. The main findings confirmed the role of personality in influencing riding behavior directly as well as indirectly through risk perception. In particular, risk perception was a significant mediator between personality, social norm, and riding behavior. The significant relations that emerged in the general sample were further confirmed in the two specific sub-samples of males and females. In terms of social marketing and educational communication, it may consequently be advisable to proceed in an integrated and coordinated manner at both the cognitive and social level, taking into account some "dispositions to risk" related to personality. The integrated and coordinated action on different levels--cognitive, social, and personality--may therefore allow more effective and significant results in reducing those risky riding behaviors that often underlie young two-wheel riders' higher involvement in traffic accidents. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.

  6. On minimizing mechanical stresses of the rail way wheels

    International Nuclear Information System (INIS)

    Moosavi, H.; Esfahanian, M.

    2000-01-01

    The purpose of this paper is to study the behavior of elastic-plastic stresses under severe drag braking. A railway wheel performs three tasks, aiding in trian movement, supporting the car load, and acting as a brake drum. Finite element computer programs are developed for elasto-plastic stress analysis. An attempt is made here to find an improved fillet profile of the wheel with the intention of minimizing high tensile mechanical stresses. Three new fillet profiles for the wheel are tested. A penalty function is used as a criterion for comparison of stresses between the new designs and the old design. The design with the least penalty is chosen to be the improved one

  7. Fuzzy model for predicting the number of deformed wheels

    Directory of Open Access Journals (Sweden)

    Ž. Đorđević

    2015-10-01

    Full Text Available Deformation of the wheels damage cars and rails and affect on vehicle stability and safety. Repair and replacement cause high costs and lack of wagons. Planning of maintenance of wagons can not be done without estimates of the number of wheels that will be replaced due to wear and deformation in a given period of time. There are many influencing factors, the most important are: weather conditions, quality of materials, operating conditions, and distance between the two replacements. The fuzzy logic model uses the collected data as input variables to predict the output variable - number of deformed wheels for a certain type of vehicle in the defined period at a particular section of the railway.

  8. Modeling and analysis of linearized wheel-rail contact dynamics

    International Nuclear Information System (INIS)

    Soomro, Z.

    2014-01-01

    The dynamics of the railway vehicles are nonlinear and depend upon several factors including vehicle speed, normal load and adhesion level. The presence of contaminants on the railway track makes them unpredictable too. Therefore in order to develop an effective control strategy it is important to analyze the effect of each factor on dynamic response thoroughly. In this paper a linearized model of a railway wheel-set is developed and is later analyzed by varying the speed and adhesion level by keeping the normal load constant. A wheel-set is the wheel-axle assembly of a railroad car. Patch contact is the study of the deformation of solids that touch each other at one or more points. (author)

  9. Wheel-running in a transgenic mouse model of Alzheimer's disease: protection or symptom?

    Science.gov (United States)

    Richter, Helene; Ambrée, Oliver; Lewejohann, Lars; Herring, Arne; Keyvani, Kathy; Paulus, Werner; Palme, Rupert; Touma, Chadi; Schäbitz, Wolf-Rüdiger; Sachser, Norbert

    2008-06-26

    Several studies on both humans and animals reveal benefits of physical exercise on brain function and health. A previous study on TgCRND8 mice, a transgenic model of Alzheimer's disease, reported beneficial effects of premorbid onset of long-term access to a running wheel on spatial learning and plaque deposition. Our study investigated the effects of access to a running wheel after the onset of Abeta pathology on behavioural, endocrinological, and neuropathological parameters. From day 80 of age, the time when Abeta deposition becomes apparent, TgCRND8 and wildtype mice were kept with or without running wheel. Home cage behaviour was analysed and cognitive abilities regarding object recognition memory and spatial learning in the Barnes maze were assessed. Our results show that, in comparison to Wt mice, Tg mice were characterised by impaired object recognition memory and spatial learning, increased glucocorticoid levels, hyperactivity in the home cage and high levels of stereotypic behaviour. Access to a running wheel had no effects on cognitive or neuropathological parameters, but reduced the amount of stereotypic behaviour in transgenics significantly. Furthermore, wheel-running was inversely correlated with stereotypic behaviour, suggesting that wheel-running may have stereotypic qualities. In addition, wheel-running positively correlated with plaque burden. Thus, in a phase when plaques are already present in the brain, it may be symptomatic of brain pathology, rather than protective. Whether or not access to a running wheel has beneficial effects on Alzheimer-like pathology and symptoms may therefore strongly depend on the exact time when the wheel is provided during development of the disease.

  10. Multi-component lightweight gearwheels with deep-drawn wheel body for automotive applications

    Science.gov (United States)

    Benkert, Tim; Hiller, Maria; Volk, Wolfram

    2017-09-01

    Multi-component gearwheels offer great lightweight opportunities for automotive applications. An assembly of a gear ring and a wheel body joined by press fit replaces the monolithic gearwheel. To save weight, the wheel body uses lightweight design. This lightweight design influences the assembled gearwheel’s mechanical properties like stiffness, weight and torque capacity. Further, the wheel body material influences the mentioned properties as well. In this paper, the effects of the lightweight wheel body manufactured by deep-drawing on the mechanical properties of the assembled gearwheel are investigated. Three different wheel body designs are examined regarding their stiffness and weight compared to a reference gearwheel. Using the best design, the influence of five materials with increasing yield strength on the maximum torque the gearwheel can transmit is studied. All research is done virtually using Abaqus 6.12-3.

  11. Transmission access and retail wheeling. The key questions

    International Nuclear Information System (INIS)

    Casazza, J.A.

    1996-01-01

    The key questions involving transmission access and retail wheeling are discussed, distinguishing between opposing views regarding the effect on system costs and the environment, particularly on optimal planning involving matching capacity and demand, generation use, demand side management, and economic operations. Also discussed are contrasting views regarding the effect of cost control pressures, regulatory advantages and disadvantages, the impact on system reliability, and the stranding of investment. The author's key concern is the effect of retail wheeling upon optimal planning and operation i.e., will competitors be willing to provide one another with the cost and technical information required for coordination? In his worst scenario, retail wheeling may lead to substantial production cost increases, lessened reliability, and unfair cost-shifting between customer classes. More optimistically, production costs and reliability may be unaffected and the cost-shifting could be salubrious. 7 figs., 11 refs

  12. Possibilities of using welding-on technologies in crane wheel ...

    Indian Academy of Sciences (India)

    WINTEC

    Abstract. The paper deals with analysis of welds-on quality of traverse crane wheels made from gr. 90–60 mate- rial, ASTM A148. Three types of welding-on technology with various filling materials were used. On wheel after wearing was welded-on one interlayer by a combination of additional materials, wire A 106 with F 11 ...

  13. A hydraulic device for unloading coke

    Energy Technology Data Exchange (ETDEWEB)

    Kretinin, M.V.; Abizgildin, U.M.; Kirillov, T.S.; Makarov, M.I.; Prokopov, O.I.; Solov' ev, A.M.

    1979-07-15

    A hydraulic device for unloading petroleum coke from slow carbonization chambers is characterized by an arrangement whereby in order to increase the output of large size coke by controlling the increment of the cutting line of the coke, the mechanism used to move the rod in the hydraulic cutter is built in the form of a rod rotation rotor; a gear wheel is mounted on the immobile section of this rotor, and on the mobile section a multi-stage regulator is installed. The drive gear of the regulator is engaged with the gear wheel, while the driven gear is connected to the rack, which is fastened to the rod.

  14. Opportunity's Surroundings After Sol 1820 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). South is at the center; north at both ends. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  15. Wheel running decreases palatable diet preference in Sprague-Dawley rats.

    Science.gov (United States)

    Moody, Laura; Liang, Joy; Choi, Pique P; Moran, Timothy H; Liang, Nu-Chu

    2015-10-15

    Physical activity has beneficial effects on not only improving some disease conditions but also by preventing the development of multiple disorders. Experiments in this study examined the effects of wheel running on intakes of chow and palatable diet e.g. high fat (HF) or high sucrose (HS) diet in male and female Sprague-Dawley rats. Experiment 1 demonstrated that acute wheel running results in robust HF or HS diet avoidance in male rats. Although female rats with running wheel access initially showed complete avoidance of the two palatable diets, the avoidance of the HS diet was transient. Experiment 2 demonstrated that male rats developed decreased HF diet preferences regardless of the order of diet and wheel running access presentation. Running associated changes in HF diet preference in females, on the other hand, depended on the testing schedule. In female rats, simultaneous presentation of the HF diet and running access resulted in transient complete HF diet avoidance whereas running experience prior to HF diet access did not affect the high preference for the HF diet. Ovariectomy in females resulted in HF diet preference patterns that were similar to those in male rats during simultaneous exposure of HF and wheel running access but similar to intact females when running occurred before HF exposure. Overall, the results demonstrated wheel running associated changes in palatable diet preferences that were in part sex dependent. Furthermore, ovarian hormones play a role in some of the sex differences. These data reveal complexity in the mechanisms underlying exercise associated changes in palatable diet preference. Published by Elsevier Inc.

  16. Wheel running decreases palatable diet preference in Sprague-Dawley rats

    Science.gov (United States)

    Moody, Laura; Liang, Joy; Choi, Pique P.; Moran, Timothy H.; Liang, Nu-Chu

    2015-01-01

    Physical activity has beneficial effects on not only improving some disease conditions but also by preventing the development of multiple disorders. Experiments in this study examined the effects of wheel running on intakes of chow and palatable diet e.g. high fat (HF) or high sucrose (HS) diet in male and female Sprague Dawley rats. Experiment 1 demonstrated that acute wheel running results in robust HF or HS diet avoidance in male rats. Although female rats with running wheel access initially showed complete avoidance of the two palatable diets, the avoidance of the HS diet was transient. Experiment 2 demonstrated that male rats developed decreased HF diet preferences regardless of the order of diet and wheel running access presentation. Running associated changes in HF diet preference in females, on the other hand, depended on the testing schedule. In female rats, simultaneous presentation of the HF diet and running access resulted in transient complete HF diet avoidance whereas running experience prior to HF diet access did not affect the high preference for the HF diet. Ovariectomy in females resulted in HF diet preference patterns that were similar to those in male rats during simultaneous exposure of HF and wheel running access but similar to intact females when running occurred before HF exposure. Overall, the results demonstrated wheel running associated changes in palatable diet preferences that were in part sex dependent. Furthermore, ovarian hormones play a role in some of the sex differences. These data reveal complexity in the mechanisms underlying exercise associated changes in palatable diet preference. PMID:25791204

  17. Time-resolved spectroscopy using a chopper wheel as a fast shutter

    International Nuclear Information System (INIS)

    Wang, Shicong; Wendt, Amy E.; Boffard, John B.; Lin, Chun C.

    2015-01-01

    Widely available, small form-factor, fiber-coupled spectrometers typically have a minimum exposure time measured in milliseconds, and thus cannot be used directly for time-resolved measurements at the microsecond level. Spectroscopy at these faster time scales is typically done with an intensified charge coupled device (CCD) system where the image intensifier acts as a “fast” electronic shutter for the slower CCD array. In this paper, we describe simple modifications to a commercially available chopper wheel system to allow it to be used as a “fast” mechanical shutter for gating a fiber-coupled spectrometer to achieve microsecond-scale time-resolved optical measurements of a periodically pulsed light source. With the chopper wheel synchronized to the pulsing of the light source, the time resolution can be set to a small fraction of the pulse period by using a chopper wheel with narrow slots separated by wide spokes. Different methods of synchronizing the chopper wheel and pulsing of the light sources are explored. The capability of the chopper wheel system is illustrated with time-resolved measurements of pulsed plasmas

  18. Automated phased array ultrasonic inspection system for rail wheel sets

    International Nuclear Information System (INIS)

    Grosser, Paul; Weiland, M.G.

    2013-01-01

    This paper covers the design, system automation, calibration and validation of an automated ultrasonic system for the inspection of new and in service wheel set assemblies from diesel-electric locomotives and gondola cars. This system uses Phased Array (PA) transducers for flaw detection and Electro-Magnetic Acoustic Transducers (EMAT) for the measurement of residual stress. The system collects, analyses, evaluates and categorizes the wheel sets automatically. This data is archived for future comparison and trending. It is also available for export to a portal lathe for increased efficiency and accuracy of machining, therefore allowing prolonged wheel life.

  19. Innovative Design and Performance Evaluation of Bionic Imprinting Toothed Wheel.

    Science.gov (United States)

    Zhang, Zhihong; Wang, Xiaoyang; Tong, Jin; Stephen, Carr

    2018-01-01

    A highly efficient soil-burrowing dung beetle possesses an intricate outer contour curve on its foreleg end-tooth. This study was carried out based on evidence that this special outer contour curve has the potential of reducing soil penetration resistance and could enhance soil-burrowing efficiency. A toothed wheel is a typical agricultural implement for soil imprinting, to increase its working efficiency; the approach of the bionic geometrical structure was utilized to optimize the innovative shape of imprinting toothed wheel. Characteristics in the dung beetle's foreleg end-tooth were extracted and studied by the edge detection technique. Then, this special outer contour curve was modeled by a nine-order polynomial function and used for the innovative design of imprinting the tooth's cutting edge. Both the conventional and bionic teeth were manufactured, and traction tests in a soil bin were conducted. Taking required draft force and volume of imprinted microbasin as the evaluating indexes, operating efficiency and quality of different toothed wheels were compared and investigated. Results indicate that compared with the conventional toothed wheel, a bionic toothed wheel possesses a better forward resistance reduction property against soil and, meanwhile, can enhance the quality of soil imprinting by increasing the volume of the created micro-basin.

  20. Principle for the Validation of a Driving Support using a Computer Vision-Based Driver Modelization on a Simulator

    Directory of Open Access Journals (Sweden)

    Baptiste Rouzier

    2015-07-01

    Full Text Available This paper presents a new structure for a driving support designed to compensate for the problems caused by the behaviour of the driver without causing a feeling of unease. This assistance is based on a shared control between the human and an automatic support that computes and applies an assisting torque on the steering wheel. This torque is computed from a representation of the hazards encountered on the road by virtual potentials. However, the equilibrium between the relative influences of the human and the support on the steering wheel are difficult to find and depend upon the situation. This is why this driving support includes a modelization of the driver based on an analysis of several face features using a computer vision algorithm. The goal is to determine whether the driver is drowsy or whether he is paying attention to some specific points in order to adapt the strength of the support. The accuracy of the measurements made on the face features is estimated, and the interest of the proposal as well as the concepts raised by such assistance are studied through simulations.