WorldWideScience

Sample records for hydraulic flight control

  1. Robust sampled-data control of hydraulic flight control actuators

    OpenAIRE

    Kliffken, Markus Gustav

    1997-01-01

    In todays flight-by-wire systems the primary flight control surfaces of modern commercial and transport aircraft are driven by electro hydraulic linear actuators. Changing flight conditions as well as nonlinear actuator dynamics may be interpreted as parameter uncertainties of the linear actuator model. This demands a robust design for the controller. Here the parameter space design is used for the direct sampled-data controller synthesis. Therefore, a static output controller is choosen, the...

  2. Fuzzy robust nonlinear control approach for electro-hydraulic flight motion simulator

    Directory of Open Access Journals (Sweden)

    Han Songshan

    2015-02-01

    Full Text Available A fuzzy robust nonlinear controller for hydraulic rotary actuators in flight motion simulators is proposed. Compared with other three-order models of hydraulic rotary actuators, the proposed controller based on first-order nonlinear model is more easily applied in practice, whose control law is relatively simple. It not only does not need high-order derivative of desired command, but also does not require the feedback signals of velocity, acceleration and jerk of hydraulic rotary actuators. Another advantage is that it does not rely on any information of friction, inertia force and external disturbing force/torque, which are always difficult to resolve in flight motion simulators. Due to the special composite vane seals of rectangular cross-section and goalpost shape used in hydraulic rotary actuators, the leakage model is more complicated than that of traditional linear hydraulic cylinders. Adaptive multi-input single-output (MISO fuzzy compensators are introduced to estimate nonlinear uncertain functions about leakage and bulk modulus. Meanwhile, the decomposition of the uncertainties is used to reduce the total number of fuzzy rules. Different from other adaptive fuzzy compensators, a discontinuous projection mapping is employed to guarantee the estimation process to be bounded. Furthermore, with a sufficient number of fuzzy rules, the controller theoretically can guarantee asymptotic tracking performance in the presence of the above uncertainties, which is very important for high-accuracy tracking control of flight motion simulators. Comparative experimental results demonstrate the effectiveness of the proposed algorithm, which can guarantee transient performance and better final accurate tracking in the presence of uncertain nonlinearities and parametric uncertainties.

  3. Emergency Flight Control Using Computer-Controlled Thrust

    Science.gov (United States)

    Burcham, Frank W., Jr.; Fullerton, C. Gordon; Stewart, James F.; Gilyard, Glenn B.; Conley, Joseph A.

    1995-01-01

    Propulsion Controlled Aircraft (PCA) systems are digital electronic control systems undergoing development to provide limited maneuvering ability through variations of individual engine thrusts in multiple-engine airplanes. Provide landing capability when control surfaces inoperable. Incorporated on existing and future airplanes that include digital engine controls, digital flight controls, and digital data buses, adding no weight for additional hardware to airplane. Possible to handle total failure of hydraulic system, depending on how surfaces respond to loss of hydraulic pressure, and broken control cables or linkages. Future airplanes incorporate data from Global Positioning System for guidance to any suitable emergency runway in world.

  4. A system look at electromechanical actuation for primary flight control

    NARCIS (Netherlands)

    Lomonova, E.A.

    1997-01-01

    An overview is presented of the emergence of the ALL Electric flight control system (FCS) or power-by-wire (PBW) concept. The concept of fly-by-power refers to the actuator using electrical rather than hydraulic power. The development of the primary flight control Electromechanical Actuators (EMAs)

  5. Development and Flight Test of an Augmented Thrust-Only Flight Control System on an MD-11 Transport Airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Burken, John J.; Pappas, Drew

    1996-01-01

    An emergency flight control system using only engine thrust, called Propulsion-Controlled Aircraft (PCA), has been developed and flight tested on an MD-11 airplane. In this thrust-only control system, pilot flight path and track commands and aircraft feedback parameters are used to control the throttles. The PCA system was installed on the MD-11 airplane using software modifications to existing computers. Flight test results show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds and altitudes. The PCA approaches, go-arounds, and three landings without the use of any non-nal flight controls have been demonstrated, including instrument landing system-coupled hands-off landings. The PCA operation was used to recover from an upset condition. In addition, PCA was tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control; describes the MD-11 airplane and systems; and discusses PCA system development, operation, flight testing, and pilot comments.

  6. Manual Throttles-Only Control Effectivity for Emergency Flight Control of Transport Aircraft

    Science.gov (United States)

    Stevens, Richard; Burcham, Frank W., Jr.

    2009-01-01

    If normal aircraft flight controls are lost, emergency flight control may be attempted using only the thrust of engines. Collective thrust is used to control flightpath, and differential thrust is used to control bank angle. One issue is whether a total loss of hydraulics (TLOH) leaves an airplane in a recoverable condition. Recoverability is a function of airspeed, altitude, flight phase, and configuration. If the airplane can be recovered, flight test and simulation results on several transport-class airplanes have shown that throttles-only control (TOC) is usually adequate to maintain up-and-away flight, but executing a safe landing is very difficult. There are favorable aircraft configurations, and also techniques that will improve recoverability and control and increase the chances of a survivable landing. The DHS and NASA have recently conducted a flight and simulator study to determine the effectivity of manual throttles-only control as a way to recover and safely land a range of transport airplanes. This paper discusses TLOH recoverability as a function of conditions, and TOC landability results for a range of transport airplanes, and some key techniques for flying with throttles and making a survivable landing. Airplanes evaluated include the B-747, B-767, B-777, B-757, A320, and B-737 airplanes.

  7. Control rod drive hydraulic device

    International Nuclear Information System (INIS)

    Takekawa, Toru.

    1994-01-01

    The device of the present invention can reliably prevent a possible erroneous withdrawal of control rod driving mechanism when the pressure of a coolant line is increased by isolation operation of hydraulic control units upon periodical inspection for a BWR type reactor. That is, a coolant line is connected to the downstream of a hydraulic supply device. The coolant line is connected to a hydraulic control unit. A coolant hydraulic detection device and a pressure setting device are disposed to the coolant line. A closing signal line and a returning signal line are disposed, which connect the hydraulic supply device and a flow rate control valve for the hydraulic setting device. In the device of the present invention, even if pressure of supplied coolants is elevated due to isolation of hydraulic control units, the elevation of the hydraulic pressure can be prevented. Accordingly, reliability upon periodical reactor inspection can be improved. Further, the facility is simplified and the installation to an existent facility is easy. (I.S.)

  8. Shape-Memory-Alloy Actuator For Flight Controls

    Science.gov (United States)

    Barret, Chris

    1995-01-01

    Report proposes use of shape-memory-alloy actuators, instead of hydraulic actuators, for aerodynamic flight-control surfaces. Actuator made of shape-memory alloy converts thermal energy into mechanical work by changing shape as it makes transitions between martensitic and austenitic crystalline phase states of alloy. Because both hot exhaust gases and cryogenic propellant liquids available aboard launch rockets, shape-memory-alloy actuators exceptionally suited for use aboard such rockets.

  9. Development and Flight Test of an Emergency Flight Control System Using Only Engine Thrust on an MD-11 Transport Airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Burken, John J.; Maine, Trindel A.; Fullerton, C. Gordon

    1997-01-01

    An emergency flight control system that uses only engine thrust, called the propulsion-controlled aircraft (PCA) system, was developed and flight tested on an MD-11 airplane. The PCA system is a thrust-only control system, which augments pilot flightpath and track commands with aircraft feedback parameters to control engine thrust. The PCA system was implemented on the MD-11 airplane using only software modifications to existing computers. Results of a 25-hr flight test show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds, altitudes, and configurations. PCA approaches, go-arounds, and three landings without the use of any normal flight controls were demonstrated, including ILS-coupled hands-off landings. PCA operation was used to recover from an upset condition. The PCA system was also tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control, a history of accidents or incidents in which some or all flight controls were lost, the MD-11 airplane and its systems, PCA system development, operation, flight testing, and pilot comments.

  10. A flight simulator control system using electric torque motors

    Science.gov (United States)

    Musick, R. O.; Wagner, C. A.

    1975-01-01

    Control systems are required in flight simulators to provide representative stick and rudder pedal characteristics. A system has been developed that uses electric dc torque motors instead of the more common hydraulic actuators. The torque motor system overcomes certain disadvantages of hydraulic systems, such as high cost, high power consumption, noise, oil leaks, and safety problems. A description of the torque motor system is presented, including both electrical and mechanical design as well as performance characteristics. The system develops forces sufficiently high for most simulations, and is physically small and light enough to be used in most motion-base cockpits.

  11. Researching on YH100 Numerical Control Servo Press Hydraulic Control System and Control Algorithm

    Directory of Open Access Journals (Sweden)

    Kai LI

    2014-09-01

    Full Text Available In order to study the numerical control (NC servo press hydraulic control system and its control algorithm. The numerical control servo press performance and control principle of hydraulic control system are analyzed. According to the flow equation of the hydraulic control valve, hydraulic cylinder flow continuity equation and the force balance equation of the hydraulic cylinder with load press, the mathematical model of hydraulic control system is established. And the servo press hydraulic system transfer function is deduced. Introducing the suitable immune particle swarm control algorithm for servo press hydraulic system, and the control system block diagram is established. Immune algorithm is used to optimize new control parameters of the system and adopt the new optimization results to optimize the system simulation. The simulation result shows that the hydraulic system’s transition time controlled by the immune particle swarm algorithm is shorter than traditional ones, and the control performance is obviously improved. Finally it can be concluded that immune particle swarm PID control have these characteristics such as quickness, stability and accuracy. Applying this principle into application, the obtained YH100 numerical control servo press hydraulic control system meets the requirement.

  12. HYDRAULIC SERVO CONTROL MECHANISM

    Science.gov (United States)

    Hussey, R.B.; Gottsche, M.J. Jr.

    1963-09-17

    A hydraulic servo control mechanism of compact construction and low fluid requirements is described. The mechanism consists of a main hydraulic piston, comprising the drive output, which is connected mechanically for feedback purposes to a servo control piston. A control sleeve having control slots for the system encloses the servo piston, which acts to cover or uncover the slots as a means of controlling the operation of the system. This operation permits only a small amount of fluid to regulate the operation of the mechanism, which, as a result, is compact and relatively light. This mechanism is particuiarly adaptable to the drive and control of control rods in nuclear reactors. (auth)

  13. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    International Nuclear Information System (INIS)

    Kim, Hyo-gon; Han, Changsoo; Lee, Jong-won; Park, Sangdeok

    2015-01-01

    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program

  14. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo-gon; Han, Changsoo [Hanyang University, Seoul (Korea, Republic of); Lee, Jong-won [Korea University of Science and Technology, Seoul (Korea, Republic of); Park, Sangdeok [Korea Institute of Industrial Technology, Seoul (Korea, Republic of)

    2015-02-15

    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program.

  15. Control rod driving hydraulic pressure device

    International Nuclear Information System (INIS)

    Ishida, Kazuo.

    1990-01-01

    Discharged water after actuating control rod drives in a BWR type reactor is once discharged to a discharging header, then returned to a master control unit and, subsequently, discharged to a reactor by way of a cooling water header. The radioactive level in the discharging header and the master control unit is increased by the reactor water to increase the operator's exposure. In view of the above, a riser is disposed for connecting a hydraulic pressure control unit incorporating a directional control valve and the cooling water head. When a certain control rod is inserted, the pressurized driving water is supplied through a hydraulic pressure control unit to the control rod drives. The discharged water from the control rod drives is entered by way of the hydraulic pressure control unit into the cooling water header and then returned to the reactor by way of other hydraulic pressure control unit and the control rod drives. Thus, the reactor water is no more recycled to the master control unit to reduce the radioactive exposure. (N.H.)

  16. Flight Measurements of the Effect of a Controllable Thrust Reverser on the Flight Characteristics of a Single-Engine Jet Airplane

    Science.gov (United States)

    Anderson, Seth B.; Cooper, George E.; Faye, Alan E., Jr.

    1959-01-01

    A flight investigation was undertaken to determine the effect of a fully controllable thrust reverser on the flight characteristics of a single-engine jet airplane. Tests were made using a cylindrical target-type reverser actuated by a hydraulic cylinder through a "beep-type" cockpit control mounted at the base of the throttle. The thrust reverser was evaluated as an in-flight decelerating device, as a flight path control and airspeed control in landing approach, and as a braking device during the ground roll. Full deflection of the reverser for one reverser configuration resulted in a reverse thrust ratio of as much as 85 percent, which at maximum engine power corresponded to a reversed thrust of 5100 pounds. Use of the reverser in landing approach made possible a wide selection of approach angles, a large reduction in approach speed at steep approach angles, improved control of flight path angle, and more accuracy in hitting a given touchdown point. The use of the reverser as a speed brake at lower airspeeds was compromised by a longitudinal trim change. At the lower airspeeds and higher engine powers there was insufficient elevator power to overcome the nose-down trim change at full reverser deflection.

  17. Hydraulic loop: practices using open control systems

    International Nuclear Information System (INIS)

    Carrasco, J.A.; Alonso, L.; Sanchez, F.

    1998-01-01

    The Tecnatom Hydraulic Loop is a dynamic training platform. It has been designed with the purpose of improving the work in teams. With this system, the student can obtain a full scope vision of a system. The hydraulic Loop is a part of the Tecnatom Maintenance Centre. The first objective of the hydraulic Loop is the instruction in components, process and process control using open control system. All the personal of an electric power plant can be trained in the Hydraulic Loop with specific courses. The development of a dynamic tool for tests previous to plant installations has been an additional objective of the Hydraulic Loop. The use of this platform is complementary to the use of full-scope simulators in order to debug and to analyse advanced control strategies. (Author)

  18. Multimodel Robust Control for Hydraulic Turbine

    OpenAIRE

    Osuský, Jakub; Števo, Stanislav

    2014-01-01

    The paper deals with the multimodel and robust control system design and their combination based on M-Δ structure. Controller design will be done in the frequency domain with nominal performance specified by phase margin. Hydraulic turbine model is analyzed as system with unstructured uncertainty, and robust stability condition is included in controller design. Multimodel and robust control approaches are presented in detail on hydraulic turbine model. Control design approaches are compared a...

  19. Highly reliable electro-hydraulic control system

    International Nuclear Information System (INIS)

    Mande, Morima; Hiyama, Hiroshi; Takahashi, Makoto

    1984-01-01

    The unscheduled shutdown of nuclear power stations disturbs power system, and exerts large influence on power generation cost due to the lowering of capacity ratio; therefore, high reliability is required for the control system of nuclear power stations. Toshiba Corp. has exerted effort to improve the reliability of the control system of power stations, and in this report, the electro-hydraulic control system for the turbines of nuclear power stations is described. The main functions of the electro-hydraulic control system are the control of main steam pressure with steam regulation valves and turbine bypass valves, the control of turbine speed and load, the prevention of turbine overspeed, the protection of turbines and so on. The system is composed of pressure sensors and a speed sensor, the control board containing the electronic circuits for control computation and protective sequence, the oil cylinders, servo valves and opening detectors of the valves for control, a high pressure oil hydraulic machine and piping, the operating panel and so on. The main features are the adoption of tripling intermediate value selection method, the multiplying of protection sensors and the adoption of 2 out of 3 trip logic, the multiplying of power sources, the improvement of the reliability of electronic circuit hardware and oil hydraulic system. (Kako, I.)

  20. Control rod driving hydraulic device

    International Nuclear Information System (INIS)

    Sugano, Hiroshi.

    1993-01-01

    In a control rod driving hydraulic device for an improved BWR type reactor, a bypass pipeline is disposed being branched from a scram pipeline, and a control orifice and a throttle valve are interposed to the bypass pipeline for restricting pressure. Upon occurrence of scram, about 1/2 of water quantity flowing from an accumulator of a hydraulic control unit to the lower surface of a piston of control rod drives by way of a scram pipeline is controlled by the restricting orifice and the throttle valve, by which the water is discharged to a pump suction pipeline or other pipelines by way of the bypass pipeline. With such procedures, a function capable of simultaneously conducting scram for two control rod drives can be attained by one hydraulic control unit. Further, an excessive peak pressure generated by a water hammer phenomenon in the scram pipeline or the control rod drives upon occurrence of scram can be reduced. Deformation and failure due to the excessive peak pressure can be prevented, as well as vibrations and degradation of performance of relevant portions can be prevented. (N.H.)

  1. Analysis of buffering process of control rod hydraulic absorber

    International Nuclear Information System (INIS)

    Bao Jishi; Qin Benke; Bo Hanliang

    2011-01-01

    Control Rod Hydraulic Drive Mechanism(CRHDM) is a newly invented build-in control rod drive mechanism. Hydraulic absorber is the key part of this mechanism, and is used to cushion the control rod when the rod scrams. Thus, it prevents the control rod from being deformed and damaged. In this paper dynamics program ANSYS CFX is used to calculate all kinds of flow conditions in hydraulic absorber to obtain its hydraulic characteristics. Based on the flow resistance coefficients obtained from the simulation results, fluid mass and momentum equations were developed to get the trend of pressure change in the hydraulic cylinder and the displacement of the piston rod during the buffering process of the control rod. The results obtained in this paper indicate that the hydraulic absorber meets the design requirement. The work in this paper will be helpful for the design and optimization of the control rod hydraulic absorber. (author)

  2. Nonlinear Control of Hydraulic Manipulator for Decommissioning Nuclear Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myoung-Ho; Lee, Sung-Uk; Kim, Chang-Hoi; Choi, Byung-Seon; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Robot technique is need to decommission nuclear reactor because of high radiation environment. Especially, Manipulator systems are useful for dismantling complex structure in a nuclear facility. In addition, Hydraulic system is applied to handle heavy duty object. Since hydraulic system can demonstrate high power. The manipulator with hydraulic power is already developed. To solve this problem, various nonlinear control method includes acceleration control. But, it is difficult because acceleration value is highly noisy. In this paper, the nonlinear control algorithm without acceleration control is studied. To verify, the hydraulic manipulator model had been developed. Furthermore, the numerical simulation is carried out. The nonlinear control without acceleration parameter method is developed for hydraulic manipulator. To verify control algorithm, the manipulator is modeled by MBD and the hydraulic servo system is also derived. In addition, the numerical simulation is also carried out. Especially, PID gain is determined though TDC algorithm. In the result of numerical simulation, tracking performance is good without acceleration control. Thus, the PID though TDC with SMC is good for hydraulic manipulator control.

  3. Nonlinear Control of Hydraulic Manipulator for Decommissioning Nuclear Reactor

    International Nuclear Information System (INIS)

    Kim, Myoung-Ho; Lee, Sung-Uk; Kim, Chang-Hoi; Choi, Byung-Seon; Moon, Jei-Kwon

    2016-01-01

    Robot technique is need to decommission nuclear reactor because of high radiation environment. Especially, Manipulator systems are useful for dismantling complex structure in a nuclear facility. In addition, Hydraulic system is applied to handle heavy duty object. Since hydraulic system can demonstrate high power. The manipulator with hydraulic power is already developed. To solve this problem, various nonlinear control method includes acceleration control. But, it is difficult because acceleration value is highly noisy. In this paper, the nonlinear control algorithm without acceleration control is studied. To verify, the hydraulic manipulator model had been developed. Furthermore, the numerical simulation is carried out. The nonlinear control without acceleration parameter method is developed for hydraulic manipulator. To verify control algorithm, the manipulator is modeled by MBD and the hydraulic servo system is also derived. In addition, the numerical simulation is also carried out. Especially, PID gain is determined though TDC algorithm. In the result of numerical simulation, tracking performance is good without acceleration control. Thus, the PID though TDC with SMC is good for hydraulic manipulator control

  4. Flight Test of an Intelligent Flight-Control System

    Science.gov (United States)

    Davidson, Ron; Bosworth, John T.; Jacobson, Steven R.; Thomson, Michael Pl; Jorgensen, Charles C.

    2003-01-01

    The F-15 Advanced Controls Technology for Integrated Vehicles (ACTIVE) airplane (see figure) was the test bed for a flight test of an intelligent flight control system (IFCS). This IFCS utilizes a neural network to determine critical stability and control derivatives for a control law, the real-time gains of which are computed by an algorithm that solves the Riccati equation. These derivatives are also used to identify the parameters of a dynamic model of the airplane. The model is used in a model-following portion of the control law, in order to provide specific vehicle handling characteristics. The flight test of the IFCS marks the initiation of the Intelligent Flight Control System Advanced Concept Program (IFCS ACP), which is a collaboration between NASA and Boeing Phantom Works. The goals of the IFCS ACP are to (1) develop the concept of a flight-control system that uses neural-network technology to identify aircraft characteristics to provide optimal aircraft performance, (2) develop a self-training neural network to update estimates of aircraft properties in flight, and (3) demonstrate the aforementioned concepts on the F-15 ACTIVE airplane in flight. The activities of the initial IFCS ACP were divided into three Phases, each devoted to the attainment of a different objective. The objective of Phase I was to develop a pre-trained neural network to store and recall the wind-tunnel-based stability and control derivatives of the vehicle. The objective of Phase II was to develop a neural network that can learn how to adjust the stability and control derivatives to account for failures or modeling deficiencies. The objective of Phase III was to develop a flight control system that uses the neural network outputs as a basis for controlling the aircraft. The flight test of the IFCS was performed in stages. In the first stage, the Phase I version of the pre-trained neural network was flown in a passive mode. The neural network software was running using flight data

  5. Robust Control of a Hydraulically Actuated Manipulator Using Sliding Mode Control

    DEFF Research Database (Denmark)

    Hansen, Michael Rygaard; Andersen, Torben Ole; Pedersen, Henrik Clemmensen

    2005-01-01

    This paper presents an approach to robust control called sliding mode control (SMC) applied to the a hydraulic servo system (HSS), consisting of a servo valve controlled symmetrical cylinder. The motivation for applying sliding mode control to hydraulically actuated systems is its robustness...

  6. Hydraulically powered dissimilar teleoperated system controller design

    International Nuclear Information System (INIS)

    Jansen, J.F.; Kress, R.L.

    1996-01-01

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented

  7. Pressure control of hydraulic servo system using proportional control valve

    International Nuclear Information System (INIS)

    Yang, Kyong Uk; Oh, In Ho; Lee, Ill Yeong

    1999-01-01

    The purpose of this study is to develop a control scheme for the hydraulic servo system which can rapidly control the pressure in a hydraulic cylinder with very short stroke. Compared with the negligible stroke of the cylinder in the system, the flow gain of the proportional pressure control valve constituting the hydraulic servo system is relatively large and the time delay on the response of the valve is quite long. Therefore, the pressure control system, in this study tends to get unstable during operations. Considering the above mentioned characteristics of the system, a two-degree-of-freedom control scheme, composed of the I-PDD 2 ... feedback compensator and the feedforward controller, is proposed. The reference model scheme is used in deciding the parameters of the controllers. The validity of the proposed control scheme is confirmed through the experiments

  8. Flight control actuation system

    Science.gov (United States)

    Wingett, Paul T. (Inventor); Gaines, Louie T. (Inventor); Evans, Paul S. (Inventor); Kern, James I. (Inventor)

    2006-01-01

    A flight control actuation system comprises a controller, electromechanical actuator and a pneumatic actuator. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. When the electromechanical actuator load level exceeds 40 amps positive, the controller activates the pneumatic actuator to offset electromechanical actuator loads to assist the manipulation of flight control surfaces. The assistance from the pneumatic load assist actuator enables the use of an electromechanical actuator that is smaller in size and mass, requires less power, needs less cooling processes, achieves high output forces and adapts to electrical current variations. The flight control actuation system is adapted for aircraft, spacecraft, missiles, and other flight vehicles, especially flight vehicles that are large in size and travel at high velocities.

  9. Hydraulic Actuators with Autonomous Hydraulic Supply for the Mainline Aircrafts

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2014-01-01

    Full Text Available Applied in the aircraft control systems, hydraulic servo actuators with autonomous hydraulic supply, so-called, hydraulic actuators of integrated configuration, i.e. combination of a source of hydraulic power and its load in the single unit, are aimed at increasing control system reliability both owing to elimination of the pipelines connecting the actuator to the hydraulic supply source, and owing to avoidance of influence of other loads failure on the actuator operability. Their purpose is also to raise control system survivability by eliminating the long pipeline communications and their replacing for the electro-conductive power supply system, thus reducing the vulnerability of systems. The main reason for a delayed application of the hydraulic actuators in the cutting-edge aircrafts was that such aircrafts require hydraulic actuators of considerably higher power with considerable heat releases, which caused an unacceptable overheat of the hydraulic actuators. Positive and negative sides of the hydraulic actuators, their alternative options of increased reliability and survivability, local hydraulic systems as an advanced alternative to independent hydraulic actuators are considered.Now to use hydraulic actuators in mainline aircrafts is inexpedient since there are the unfairly large number of the problems reducing, first and last, safety of flights, with no essential weight and operational advantages. Still works to create competitive hydraulic actuators ought to be continued.Application of local hydraulic systems (LHS will allow us to reduce length of pressure head and drain pipelines and mass of pipelines, as well as to raise their general fail-safety and survivability. Application of the LHS principle will allow us to use a majority of steering drive advantages. It is necessary to allocate especially the following:- ease of meeting requirements for the non-local spread of the engine weight;- essentially reducing length and weight of

  10. Precision Force Control for an Electro-Hydraulic Press Machine

    Directory of Open Access Journals (Sweden)

    Hong-Ming Chen

    2014-08-01

    Full Text Available This thesis is primarily intended to design a PC-based control system to control the force of an electro-hydraulic servo press system for implementing precision force control. The main feature is to develop a composite control by using the relief valve and the flow servo valve. Using feedback from a force sensor, a fuzzy controller was designed with LabVIEW software as the system control core for achieving a precision force control for the hydraulic cylinder on its travel and output. The weakness of hydraulic systems is that hydraulic oil is compressible and prone to leaking, and its characteristics can vary with oil temperature, thus making it difficult for a general linear controller to achieve accurate control. Therefore, a fuzzy controller was designed with LabVIEW along with a NI-PCI_6221 interface card and a load cell to control the servo valve flow and the relief valve to control the pressure source. The testing results indicate that accurate force control output of an electro-hydraulic servo press system can be obtained.

  11. Hydraulic system for driving control rods

    International Nuclear Information System (INIS)

    Okuzumi, Naoaki.

    1982-01-01

    Purpose: To enable safety reactor shut down upon occurrence of an abnormal excess pressure in a hydraulic control unit. Constitution: The actuation pressure for a pressure switch that generates a scram signal is set lower than the release pressure set to a pressure release valve. Thus, if the pressure of nitrogen gas in a nitrogen container increases such as upon exposure of the hydraulic control unit to a high temperature, the pressure switch is actuated at first to generate the scram signal and a scram valve is opened to supply water at high pressure to control rod drives under the driving force of the nitrogen gas at high pressure to rapidly insert the control element into the reactor and shut down it. If the pressure of the nitrogen gas still increases after the scram, the pressure release valve is opened to release the nitrogen gas at high temperature to the atmosphere. Since the scram is attained before the actuation of the pressure release valve, safety reactor shut down can be attained and the hydraulic control unit can be protected. (Sekiya, K.)

  12. Observer-Based Robust Control for Hydraulic Velocity Control System

    Directory of Open Access Journals (Sweden)

    Wei Shen

    2013-01-01

    Full Text Available This paper investigates the problems of robust stabilization and robust control for the secondary component speed control system with parameters uncertainty and load disturbance. The aim is to enhance the control performance of hydraulic system based on Common Pressure Rail (CPR. Firstly, a mathematical model is presented to describe the hydraulic control system. Then a novel observer is proposed, and an observed-based control strategy is designed such that the closed-loop system is asymptotically stable and satisfies the disturbance attenuation level. The condition for the existence of the developed controller can by efficiently solved by using the MATLAB software. Finally, simulation results are provided to demonstrate the effectiveness of the proposed method.

  13. Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research Center

    Science.gov (United States)

    Carter, John; Stephenson, Mark

    1999-01-01

    The NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in the control law, handling qualities, and flight systems areas. The PSFCC feature a research flight control processor that is "piggybacked" onto the baseline F/A-18 flight control system. This research processor allows for pilot selection of research control law operation in flight. To validate flight operation, a replication of a standard F/A-18 control law was programmed into the research processor and flight-tested over a limited envelope. This paper provides a brief description of the system, summarizes the initial flight test of the PSFCC, and describes future experiments for the PSFCC.

  14. Modelling and LPV control of an electro-hydraulic servo system

    NARCIS (Netherlands)

    Naus, G.J.L.; Wijnheijmer, F.P.; Post, W.J.A.E.M.; Steinbuch, M.; Teerhuis, A.P.

    2006-01-01

    This paper aims to show the modelling and control of an hydraulic servo system, targeting at frequency domain based controller design and the implementation of a LPV controller. The actual set-up consists of a mass, moved by a hydraulic cylinder and an electro-hydraulic servo valve. A nonlinear

  15. Shock analysis on hydraulic drive control rod during scram

    International Nuclear Information System (INIS)

    Song Wei; Qin Benke; Bo Hanliang

    2013-01-01

    Control rod hydraulic drive mechanism (CRHDM) is a new invention of Institute of Nuclear and New Energy Technology of Tsinghua University. The hydraulic absorber buffers the control rod when it scrams. The control rod fast drop impact experiment was conducted and the key parameters of control rod hydraulic buffering performance were obtained. Based on the test results and according to D'Alembert principle, the maximum inertial impact force on the control rod during the fast drop period was applied as equivalent static load force on the control rod. The deformations and stress distributions on the control rod in this worst case were calculated by using finite element software ABAQUS. Calculation results were compared with the experiment results, and it was verified that nonlinear transient dynamics analysis in this problem can be simplified as static analysis. Damage criterion of the control rod fast drop impact process was also given. And it lays foundation for optimal design of the control rod and hydraulic absorber. (authors)

  16. Controls of Hydraulic Wind Turbine

    Directory of Open Access Journals (Sweden)

    Zhang Yin

    2016-01-01

    Full Text Available In this paper a hydraulic wind turbine generator system was proposed based on analysis the current wind turbines technologies. The construction and principles were introduced. The mathematical model was verified using MATLAB and AMsim. A displacement closed loop of swash plate of motor and a speed closed loop of generator were setup, a PID control is introduced to maintain a constant speed and fixed frequency at wind turbine generator. Simulation and experiment demonstrated that the system can connect grid to generate electric and enhance reliability. The control system demonstrates a high performance speed regulation and effectiveness. The results are great significant to design a new type hydraulic wind turbine system.

  17. Technology and control for hydraulic manipulators

    International Nuclear Information System (INIS)

    Measson, Y.; David, O.; Louveau, F.; Friconneau, J.P.

    2003-01-01

    Hydraulic manipulators are candidate for fusion reactor maintenance. Their main advantages are their large payload with respect to volume and mass, their reliability and their robustness. However, due to their force control limitations, they are disqualified for precise manipulation and are dangerous for the environment and themselves in case of unexpected collision. CEA, in collaboration with CYBERNETIX and IFREMER has developed the advanced hydraulic robot MAESTRO. Force and hybrid control has been developed in order to avoid the previous problems. Using 'pressure' control servo-valve instead of the standard 'flow' control servo-valve (standard configuration of the MAESTRO) makes a real simplification of the control loop. No more pressure sensors are needed for monitoring the hydraulic joint in force control mode and using this kind of valves makes big safety improvements. The French company IN-LHC, designed and manufactured a prototype of servo-valve that fits the performances and space constraints of the Maestro arm. A characterisation of this new product was made on a mock-up and a set of these prototypes integrated in the Maestro slave-arm. A comparison between the two actuating technologies was made and showed that the performances of the pressure servo-valves make it applicable to general application

  18. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States); Basher, A.M.H. [South Carolina State Univ., Orangeburg, SC (United States)

    1996-09-01

    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  19. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Kress, R.L.; Jansen, J.F.; Basher, A.M.H.

    1996-09-01

    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  20. Control issues for a hydraulically powered dissimilar teleoperated system

    International Nuclear Information System (INIS)

    Jansen, J.F.; Kress, R.L.

    1995-01-01

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schilling's Titan II hydraulic manipulators are the slave manipulators and the master manipulators are from the Oak Ridge National Laboratory-developed Advanced Servo Manipulator.)

  1. Review of fluid and control technology of hydraulic wind turbines

    Institute of Scientific and Technical Information of China (English)

    Maolin CAI; Yixuan WANG; Zongxia JIAO; Yan SHI

    2017-01-01

    This study examines the development of the fluid and control technology of hydraulic wind turbines.The current state of hydraulic wind turbines as a new technology is described,and its basic fluid model and typical control method are expounded by comparing various study results.Finally,the advantages of hydraulic wind turbines are enumerated.Hydraulic wind turbines are expected to become the main development direction of wind turbines.

  2. Review of fluid and control technology of hydraulic wind turbines

    Science.gov (United States)

    Cai, Maolin; Wang, Yixuan; Jiao, Zongxia; Shi, Yan

    2017-09-01

    This study examines the development of the fluid and control technology of hydraulic wind turbines. The current state of hydraulic wind turbines as a new technology is described, and its basic fluid model and typical control method are expounded by comparing various study results. Finally, the advantages of hydraulic wind turbines are enumerated. Hydraulic wind turbines are expected to become the main development direction of wind turbines.

  3. Scientific Research Program for Power, Energy, and Thermal Technologies. Task Order 0002: Power, Thermal and Control Technologies and Processes Experimental Research. Subtask: Laboratory Test Set-up to Evaluate Electromechanical Actuation Systems for Aircraft Flight Control

    Science.gov (United States)

    2015-08-01

    hydraulic pumps generated hydraulic pressure which, in turn, powered the actuator which would move the flight control surface to the desired position...aircraft surface controls. Figure 2 - Electro- hydrostatic Actuator and an Electro-mechanical Actuator [7] In order to have a better...as to have a flat surface for the measurement device to measure position. This method was used in order to eliminate any displacement due to slop

  4. MD-11 PCA - Research flight team photo

    Science.gov (United States)

    1995-01-01

    On Aug. 30, 1995, a the McDonnell Douglas MD-11 transport aircraft landed equipped with a computer-assisted engine control system that has the potential to increase flight safety. In landings at NASA Dryden Flight Research Center, Edwards, California, on August 29 and 30, the aircraft demonstrated software used in the aircraft's flight control computer that essentially landed the MD-11 without a need for the pilot to manipulate the flight controls significantly. In partnership with McDonnell Douglas Aerospace (MDA), with Pratt & Whitney and Honeywell helping to design the software, NASA developed this propulsion-controlled aircraft (PCA) system following a series of incidents in which hydraulic failures resulted in the loss of flight controls. This new system enables a pilot to operate and land the aircraft safely when its normal, hydraulically-activated control surfaces are disabled. This August 29, 1995, photo shows the MD-11 team. Back row, left to right: Tim Dingen, MDA pilot; John Miller, MD-11 Chief pilot (MDA); Wayne Anselmo, MD-11 Flight Test Engineer (MDA); Gordon Fullerton, PCA Project pilot; Bill Burcham, PCA Chief Engineer; Rudey Duran, PCA Controls Engineer (MDA); John Feather, PCA Controls Engineer (MDA); Daryl Townsend, Crew Chief; Henry Hernandez, aircraft mechanic; Bob Baron, PCA Project Manager; Don Hermann, aircraft mechanic; Jerry Cousins, aircraft mechanic; Eric Petersen, PCA Manager (Honeywell); Trindel Maine, PCA Data Engineer; Jeff Kahler, PCA Software Engineer (Honeywell); Steve Goldthorpe, PCA Controls Engineer (MDA). Front row, left to right: Teresa Hass, Senior Project Management Analyst; Hollie Allingham (Aguilera), Senior Project Management Analyst; Taher Zeglum, PCA Data Engineer (MDA); Drew Pappas, PCA Project Manager (MDA); John Burken, PCA Control Engineer.

  5. Design of Transputer Controllers for Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    1996-01-01

    The paper deals with how transputers can be applied for fast controllers for hydraulic actuator systems. A general transputer-based control systems including a data acquisition transputer subsystem is presented. An application case: development of a mechatronic test facility with a fast hydraulic...... test robot controlled by a transputer-basec controller is presented. Some experimental path-tracking results with adaptive control algorithms are presented and discussed. The results confirm that transputers have significant advantages for intelligent control of actuator systems and robots for high...

  6. Flight Test Implementation of a Second Generation Intelligent Flight Control System

    Science.gov (United States)

    Williams-Hayes, Peggy S.

    2005-01-01

    The NASA F-15 Intelligent Flight Control System project team has developed a series of flight control concepts designed to demonstrate the benefits of a neural network-based adaptive controller. The objective of the team was to develop and flight-test control systems that use neural network technology, to optimize the performance of the aircraft under nominal conditions, and to stabilize the aircraft under failure conditions. Failure conditions include locked or failed control surfaces as well as unforeseen damage that might occur to the aircraft in flight. The Intelligent Flight Control System team is currently in the process of implementing a second generation control scheme, collectively known as Generation 2 or Gen 2, for flight testing on the NASA F-15 aircraft. This report describes the Gen 2 system as implemented by the team for flight test evaluation. Simulation results are shown which describe the experiment to be performed in flight and highlight the ways in which the Gen 2 system meets the defined objectives.

  7. Adaptive PID and Model Reference Adaptive Control Switch Controller for Nonlinear Hydraulic Actuator

    Directory of Open Access Journals (Sweden)

    Xin Zuo

    2017-01-01

    Full Text Available Nonlinear systems are modeled as piecewise linear systems at multiple operating points, where the operating points are modeled as switches between constituent linearized systems. In this paper, adaptive piecewise linear switch controller is proposed for improving the response time and tracking performance of the hydraulic actuator control system, which is essentially piecewise linear. The controller composed of PID and Model Reference Adaptive Control (MRAC adaptively chooses the proportion of these two components and makes the designed system have faster response time at the transient phase and better tracking performance, simultaneously. Then, their stability and tracking performance are analyzed and evaluated by the hydraulic actuator control system, the hydraulic actuator is controlled by the electrohydraulic system, and its model is built, which has piecewise linear characteristic. Then the controller results are compared between PID and MRAC and the switch controller designed in this paper is applied to the hydraulic actuator; it is obvious that adaptive switch controller has better effects both on response time and on tracking performance.

  8. X-43A Flight Controls

    Science.gov (United States)

    Baumann, Ethan

    2006-01-01

    A viewgraph presentation detailing X-43A Flight controls at NASA Dryden Flight Research Center is shown. The topics include: 1) NASA Dryden, Overview and current and recent flight test programs; 2) Unmanned Aerial Vehicle Synthetic Aperture Radar (UAVSAR) Program, Program Overview and Platform Precision Autopilot; and 3) Hyper-X Program, Program Overview, X-43A Flight Controls and Flight Results.

  9. Hydraulic oil control system for transformer stations

    International Nuclear Information System (INIS)

    Truong, P.

    2002-01-01

    'Full text:' Electrical oil control systems are commonly used to contain large volumes of spilled oil in transformer stations. Specially calibrated floats, some of which are designed to float only in oil and others only in water, are used in combination with a pump to contain oil at the catch basin below a transformer station.This electrical control system requires frequent maintenance and inspections to ensure the electrical system is not affected by any electrical surges. Also the floats need to be inspected and cleaned frequently to prevent oil or grit build up that may affect the systems' ability to contain oil.Recognizing the limitations of electrical oil control systems, Hydro One is investigating alternative control systems. A hydraulic oil control system is being investigated as an alternative which can backup oil in a containment area while allowing any water entering the containment area to pass through. Figure 1 shows a schematic of a bench-top model tested at Ryerson University. Oil and water separation occurs within the double-piped column. Oil and water are allowed to enter the external pipe column but only water is allowed to exit the internal pipe column. The internal pipe column is designed to generate enough hydrostatic pressure to ensure the oil is contained in the external pipe column.The hydraulic oil control system provides a reliable control mechanism and requires less maintenance compared to that of the electrical control system. Since the hydraulic oil control system has no moving parts, nor would any parts that require electricity, it is not affected by electrical surges such as lightening.The maintenance requirements of the hydraulic oil control system are: the removal of any oil and grit from the catch basin, and the occasional visual inspection for any crack or clogs in the system. (author)

  10. A Survey of Open-Source UAV Flight Controllers and Flight Simulators

    DEFF Research Database (Denmark)

    Ebeid, Emad Samuel Malki; Skriver, Martin; Terkildsen, Kristian Husum

    2018-01-01

    , which are all tightly linked to the UAV flight controller hardware and software. The lack of standardization of flight controller architectures and the use of proprietary closed-source flight controllers on many UAV platforms, however, complicates this work: solutions developed for one flight controller...... may be difficult to port to another without substantial extra development and testing. Using open-source flight controllers mitigates some of these challenges and enables other researchers to validate and build upon existing research. This paper presents a survey of the publicly available open...

  11. A low order adaptive control scheme for hydraulic servo systems

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Pedersen, Henrik Clemmensen; Bech, Michael Møller

    2015-01-01

    This paper deals with high-performance position control of hydraulics servo systems in general. The hydraulic servo system used is a two link robotic manipulator actuated by two hydraulic servo cylinders. A non-linear model of the hydraulic system and a Newton-Euler based model of the mechanical...

  12. Hydraulic pressure control unit for control rod drive

    International Nuclear Information System (INIS)

    Watabe, Yukio.

    1990-01-01

    The pressure invention concerns a hydraulic pressure control unit for control rod drives in BWR type reactors. The space above a floating piston possessed by an accumulator and the housing of control rod drives are connected by means of a pipeline. The pipeline has a scram valve which is opened upon occurrence of reactor scram. A pump is disposed between the accumulator and the scram valve for communicating a discharge port to apply a high pressure water to the accumulator. According to the present invention, a control unit is disposed between the scram valve and the housing of the control rod drives in the hydraulic pressure control unit for maintaining the cross sectional area of the flow channel of the pipeline to a usual size when the pressure in a pressure vessel is under a rated operation pressure, while limiting the cross sectional area of the flow channel when the pressure is lower than that in the rated operation. Thus, whole insertion of the control rod substantially at a constant speed is enabled irrespective of the level of the pressure in the pressure vessel. (I.S.)

  13. Sliding Control with Chattering Elimination for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2012-01-01

    This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load characteri......This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load...... controller is developed for the control derivative based on a reduced order model. Simulation results demonstrate strong robustness when subjected to parameter perturbations and that chattering is eliminated....

  14. Adaptive Non-linear Control of Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Conrad, Finn

    1998-01-01

    Presentation of two new developed adaptive non-liner controllers for hydraulic actuator systems to give stable operation and improved performance.Results from the IMCIA project supported by the Danish Technical Research Council (STVF).......Presentation of two new developed adaptive non-liner controllers for hydraulic actuator systems to give stable operation and improved performance.Results from the IMCIA project supported by the Danish Technical Research Council (STVF)....

  15. Servo-hydraulic actuator in controllable canonical form: Identification and experimental validation

    Science.gov (United States)

    Maghareh, Amin; Silva, Christian E.; Dyke, Shirley J.

    2018-02-01

    Hydraulic actuators have been widely used to experimentally examine structural behavior at multiple scales. Real-time hybrid simulation (RTHS) is one innovative testing method that largely relies on such servo-hydraulic actuators. In RTHS, interface conditions must be enforced in real time, and controllers are often used to achieve tracking of the desired displacements. Thus, neglecting the dynamics of hydraulic transfer system may result either in system instability or sub-optimal performance. Herein, we propose a nonlinear dynamical model for a servo-hydraulic actuator (a.k.a. hydraulic transfer system) coupled with a nonlinear physical specimen. The nonlinear dynamical model is transformed into controllable canonical form for further tracking control design purposes. Through a number of experiments, the controllable canonical model is validated.

  16. Robust Hinfinity position control synthesis of an electro-hydraulic servo system.

    Science.gov (United States)

    Milić, Vladimir; Situm, Zeljko; Essert, Mario

    2010-10-01

    This paper focuses on the use of the techniques based on linear matrix inequalities for robust H(infinity) position control synthesis of an electro-hydraulic servo system. A nonlinear dynamic model of the hydraulic cylindrical actuator with a proportional valve has been developed. For the purpose of the feedback control an uncertain linearized mathematical model of the system has been derived. The structured (parametric) perturbations in the electro-hydraulic coefficients are taken into account. H(infinity) controller extended with an integral action is proposed. To estimate internal states of the electro-hydraulic servo system an observer is designed. Developed control algorithms have been tested experimentally in the laboratory model of an electro-hydraulic servo system. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Dynamic Characteristics of Communication Lines with Distributed Parameters to Control the Throttle-controlled Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    D. N. Popov

    2015-01-01

    Full Text Available The article considers a mathematical model of the hydraulic line for remote control of electro-hydraulic servo drive (EHSD with throttle control. This type of hydraulic lines is designed as a backup to replace the electrical connections, which are used to control EHSD being remote from the site with devices located to form the control signals of any object. A disadvantage of electric connections is that they are sensitive to magnetic fields and thereby do not provide the required reliability of the remote control. Hydraulic lines have no this disadvantage and therefore are used in aircraft and other industrial systems. However, dynamic characteristics of hydraulic systems still have been investigated insufficiently in the case of transmitting control signals at a distance at which the signal may be distorted when emerging the wave processes.The article results of mathematical simulation, which are verified through physical experimentation, largely eliminate the shortcomings of said information.The mathematical model described in the paper is based on the theory of unsteady pressure compressible fluids. In the model there are formulas that provide calculation of frequency characteristics of the hydraulic lines under hydraulic oscillations of the laminar flow parameters of viscous fluid.A real mock-up of the system under consideration and an experimental ad hoc unit are used to verify the results of mathematically simulated hydraulic systems.Calculated logarithmic amplitude and phase frequency characteristics compared with those obtained experimentally prove, under certain conditions, the proposed theoretical method of calculation. These conditions have to ensure compliance with initial parameters of fluid defined under stationary conditions. The applied theory takes into consideration a non-stationary hydraulic resistance of the line when calculating frequency characteristics.The scientific novelty in the article material is presented in

  18. 14 CFR 27.151 - Flight controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight controls. 27.151 Section 27.151... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight Flight Characteristics § 27.151 Flight controls. (a) Longitudinal, lateral, directional, and collective controls may not exhibit excessive breakout force, friction...

  19. 14 CFR 29.151 - Flight controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Flight controls. 29.151 Section 29.151... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight Flight Characteristics § 29.151 Flight controls. (a) Longitudinal, lateral, directional, and collective controls may not exhibit excessive breakout force, friction...

  20. TRACKING CONTROL FOR A HYDRAULIC DRIVE WITH A PRESSURE COMPENSATOR

    Directory of Open Access Journals (Sweden)

    S. V. Aranovskiy

    2015-07-01

    Full Text Available A problem of tracking control is considered for a hydraulic drive with a pressure compensator that is widespread in the equipment of heavy-duty machines. Method. The control problem is solved by means of a switching sliding-mode controller coupled with static nonlinear compensation and desired velocity feedforward. Main Results. Mathematical model of a hydraulic drive is given in view of the pressure compensator presence. Traditional model of a hydraulic drive is formulated for a system with a spool valve; purpose and principles of operation of the pressure compensator in hydraulic systems are described, and the extended model is presented illustrating compensator contribution to overall system dynamics. It is shown that the obtained model has an input static nonlinearity; the nonlinearity cancellation method is proposed giving the possibility for injection of a desired velocity feedforward term. The control law is chosen as a switching one and two chattering attenuation methods are studied: equivalent control estimation via filtering and sign function integration. Experimental studies are performed at a forestry hydraulic crane prototype and illustrate high tracking accuracy achieved for typical crane motions. Practical Significance. The results are suitable for heavy-duty hydraulic machines automation in construction, road building and forestry.

  1. Analysis of an controller design for an electro-hydraulic servo pressure regulator

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.

    2009-01-01

    Mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are starting to become standard on a high number of machines, hereby replacing hydraulic pilot lines and oering new possibilities with regard to both control and feasibility. For controlling some...... of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus of the current paper is therefore on the analysis and controller design an electro-hydraulic servo pressure...... regulator, which generates a hydraulic LS-pressure based on an electrical reference, hereby synergistically integrating knowledge from all parts of the mechatronics area. The servo pressure regulator is used to generate the LS-signal for a variable displacement pump, and the paper rst presents...

  2. Towards Autonomous Control of Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Conrad, Finn

    1998-01-01

    Presentation of new developed control algorithms to increase autonomy and intelligence of hydraulic control systems. A refinement of relaytuning method is used to determine the control parameters of a lag/lead controller and a poleplacement controller. Further, a fail-safe function is developed...

  3. Emergency Flight Control of a Twin-Jet Commercial Aircraft using Manual Throttle Manipulation

    Science.gov (United States)

    Cole, Jennifer H.; Cogan, Bruce R.; Fullerton, C. Gordon; Burken, John J.; Venti, Michael W.; Burcham, Frank W.

    2007-01-01

    The Department of Homeland Security (DHS) created the PCAR (Propulsion-Controlled Aircraft Recovery) project in 2005 to mitigate the ManPADS (man-portable air defense systems) threat to the commercial aircraft fleet with near-term, low-cost proven technology. Such an attack could potentially cause a major FCS (flight control system) malfunction or other critical system failure onboard the aircraft, despite the extreme reliability of current systems. For the situations in which nominal flight controls are lost or degraded, engine thrust may be the only remaining means for emergency flight control [ref 1]. A computer-controlled thrust system, known as propulsion-controlled aircraft (PCA), was developed in the mid 1990s with NASA, McDonnell Douglas and Honeywell. PCA's major accomplishment was a demonstration of an automatic landing capability using only engine thrust [ref 11. Despite these promising results, no production aircraft have been equipped with a PCA system, due primarily to the modifications required for implementation. A minimally invasive option is TOC (throttles-only control), which uses the same control principles as PCA, but requires absolutely no hardware, software or other aircraft modifications. TOC is pure piloting technique, and has historically been utilized several times by flight crews, both military and civilian, in emergency situations stemming from a loss of conventional control. Since the 1990s, engineers at NASA Dryden Flight Research Center (DFRC) have studied TOC, in both simulation and flight, for emergency flight control with test pilots in numerous configurations. In general, it was shown that TOC was effective on certain aircraft for making a survivable landing. DHS sponsored both NASA Dryden Flight Research Center (Edwards, CA) and United Airlines (Denver, Colorado) to conduct a flight and simulation study of the TOC characteristics of a twin-jet commercial transport, and assess the ability of a crew to control an aircraft down to

  4. Dynamic Self-Adaptive Reliability Control for Electric-Hydraulic Systems

    Directory of Open Access Journals (Sweden)

    Yi Wan

    2015-02-01

    Full Text Available The high-speed electric-hydraulic proportional control is a new development of the hydraulic control technique with high reliability, low cost, efficient energy, and easy maintenance; it is widely used in industrial manufacturing and production. However, there are still some unresolved challenges, the most notable being the requirements of high stability and real-time by the classical control algorithm due to its high nonlinear characteristics. We propose a dynamic self-adaptive mixed control method based on the least squares support vector machine (LSSVM and the genetic algorithm for high-speed electric-hydraulic proportional control systems in this paper; LSSVM is used to identify and adjust online a nonlinear electric-hydraulic proportional system, and the genetic algorithm is used to optimize the control law of the controlled system and dynamic self-adaptive internal model control and predictive control are implemented by using the mixed intelligent method. The internal model and the inverse control model are online adjusted together. At the same time, a time-dependent Hankel matrix is constructed based on sample data; thus finite dimensional solution can be optimized on finite dimensional space. The results of simulation experiments show that the dynamic characteristics are greatly improved by the mixed intelligent control strategy, and good tracking and high stability are met in condition of high frequency response.

  5. Control of spool position of on/off solenoid operated hydraulic valve by sliding-mode controller

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Hak; Hong, Hyun Wook; Park, Myeong Kwan [Pusan National University, Busan (Korea, Republic of); Yun, Young Won [KHPS, Busan (Korea, Republic of)

    2015-11-15

    The use of on/off solenoid operated hydraulic valves instead of proportional valves has been attracting the interest of many researchers and engineers. However, there exist difficulties in controlling the on/off valve because of highly nonlinear characteristics including hysteresis and saturation. This paper considers the application of on/off solenoid operated hydraulic valves to control position of a hydraulic cylinder with the aim of evaluating, feasibility and practicability of their implementation and understanding the potential benefits when they are used in existing hydraulic systems. Assuming that only the current is measured, a sliding mode observer is designed to estimate the spool position and velocity. To alleviate the aforementioned difficulties in controlling the spool position, a nonlinear observer-based controller of an on/off solenoid valve is designed, taking into account the estimated values, based on a nonlinear model including hysteresis and saturation. The control objective is to track a desired spool trajectory. Simulation and experimental results illustrate the efficiency of the designed controller. The proposed controller is validated again in a single-rod hydraulic actuator. Experimental results show that the fluid flow through the valve orifice by controlling the spool position was successfully controlled.

  6. Selected Flight Test Results for Online Learning Neural Network-Based Flight Control System

    Science.gov (United States)

    Williams-Hayes, Peggy S.

    2004-01-01

    The NASA F-15 Intelligent Flight Control System project team developed a series of flight control concepts designed to demonstrate neural network-based adaptive controller benefits, with the objective to develop and flight-test control systems using neural network technology to optimize aircraft performance under nominal conditions and stabilize the aircraft under failure conditions. This report presents flight-test results for an adaptive controller using stability and control derivative values from an online learning neural network. A dynamic cell structure neural network is used in conjunction with a real-time parameter identification algorithm to estimate aerodynamic stability and control derivative increments to baseline aerodynamic derivatives in flight. This open-loop flight test set was performed in preparation for a future phase in which the learning neural network and parameter identification algorithm output would provide the flight controller with aerodynamic stability and control derivative updates in near real time. Two flight maneuvers are analyzed - pitch frequency sweep and automated flight-test maneuver designed to optimally excite the parameter identification algorithm in all axes. Frequency responses generated from flight data are compared to those obtained from nonlinear simulation runs. Flight data examination shows that addition of flight-identified aerodynamic derivative increments into the simulation improved aircraft pitch handling qualities.

  7. Transputer Control of Hydraulic Actuators and Robots

    DEFF Research Database (Denmark)

    Conrad, Finn

    1996-01-01

    Results from a Danish mechatronics research program entitled IMCIA - Intelligent Control and Intelligent Actuators. The objective is development of intelligent actuators for intelligent motion control. A mechatronics test facility with a transputer controlled hydraulic robot suiteable for real...

  8. Flight Test Experience With an Electromechanical Actuator on the F-18 Systems Research Aircraft

    Science.gov (United States)

    Jensen, Stephen C.; Jenney, Gavin D.; Raymond, Bruce; Dawson, David

    2000-01-01

    Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

  9. Hydraulic concrete composition and properties control system

    OpenAIRE

    PSHINKO O.M.; KRASNYUK A.V.; HROMOVA O.V.

    2015-01-01

    Purpose. Scientific work aims at the development and testing of information system to meet the challenges of concrete composition design and control (for railway structures and buildings) based on the physico-analytical method algorithm for hydraulic concrete composition calculation. Methodology. The proposed algorithm of hydraulic concrete composition calculation is based on the physicochemical mechanics and in particular on the rheology of elastic–viscous–plastic bodies. The system of canon...

  10. Experimental evaluation of control strategies for hydraulic servo robot

    DEFF Research Database (Denmark)

    Bech, Michael Møller; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    In this paper different linear and non-linear controllers applied to a hydraulically driven servo robot are evaluated and validated. The task is to make the actuators of the manipulator track a position reference with minimum error. Hydraulic systems are intrinsically non-linear and using linear...... in industrial servo drives. The different controllers are compared and evaluated from simulation and experimental results....

  11. Device for controlling the hydraulic lifter of drilling unit

    Energy Technology Data Exchange (ETDEWEB)

    Kraskov, P N

    1981-04-10

    A device is suggested for controlling the hydraulic lifter of a drilling unit. It contains a throttling valve with cylinder for servocontrol, mechanism for assigning the program for lowering velocity connected to the power cylinder, and oil tank. In order to improve the reliable concentration of the drilling unit by guaranteeing possible alternation for halting descent when the string falls on a projection in the well, the device is equipped with a normally open two-position hydraulically controlled distributor with spring return connected to the working surface of the power cylinder and valve connected to it with logical function of ILI for hydraulic control of the normally opened two-position distributor. The latter connects the working cavity of the servocontrol cylinder with the oil tank.

  12. Nonlinear control for a class of hydraulic servo system.

    Science.gov (United States)

    Yu, Hong; Feng, Zheng-jin; Wang, Xu-yong

    2004-11-01

    The dynamics of hydraulic systems are highly nonlinear and the system may be subjected to non-smooth and discontinuous nonlinearities due to directional change of valve opening, friction, etc. Aside from the nonlinear nature of hydraulic dynamics, hydraulic servo systems also have large extent of model uncertainties. To address these challenging issues, a robust state-feedback controller is designed by employing backstepping design technique such that the system output tracks a given signal arbitrarily well, and all signals in the closed-loop system remain bounded. Moreover, a relevant disturbance attenuation inequality is satisfied by the closed-loop signals. Compared with previously proposed robust controllers, this paper's robust controller based on backstepping recursive design method is easier to design, and is more suitable for implementation.

  13. TG 220 MW hydraulic control system diagnostics

    International Nuclear Information System (INIS)

    Svabcik, A.

    1996-01-01

    The TG power output control system comprises a hydraulic and an electronic part. TG speed, power output or the main steam header pressure (HPK) depend on the steam flow at the turbine inlet. The steam admission into the turbine is controlled by four control valves and one by-pass valve in case of the HP part and by four capture flap valves in case of the LP part. The task of the SKODA K-220 MW turbine protection and control systems is to provide both the turbine speed and power output control to the setpoint value. Diagnostic measurements were aimed at getting an overview of both technical and functional states of all power output control elements. Principally, it can be stated that some deficiencies of a design nature originating from the manufacturer's factory were revealed and some other deficiencies related to hydraulic control elements functionality were identified more closely by the new method. 5 figs

  14. TG 220 MW hydraulic control system diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Svabcik, A [Atomova Elektraren Bohunice, Jaslovske Bohunice (Slovakia)

    1997-12-31

    The TG power output control system comprises a hydraulic and an electronic part. TG speed, power output or the main steam header pressure (HPK) depend on the steam flow at the turbine inlet. The steam admission into the turbine is controlled by four control valves and one by-pass valve in case of the HP part and by four capture flap valves in case of the LP part. The task of the SKODA K-220 MW turbine protection and control systems is to provide both the turbine speed and power output control to the setpoint value. Diagnostic measurements were aimed at getting an overview of both technical and functional states of all power output control elements. Principally, it can be stated that some deficiencies of a design nature originating from the manufacturer`s factory were revealed and some other deficiencies related to hydraulic control elements functionality were identified more closely by the new method. 5 figs.

  15. Advanced transport operating system software upgrade: Flight management/flight controls software description

    Science.gov (United States)

    Clinedinst, Winston C.; Debure, Kelly R.; Dickson, Richard W.; Heaphy, William J.; Parks, Mark A.; Slominski, Christopher J.; Wolverton, David A.

    1988-01-01

    The Flight Management/Flight Controls (FM/FC) software for the Norden 2 (PDP-11/70M) computer installed on the NASA 737 aircraft is described. The software computes the navigation position estimates, guidance commands, those commands to be issued to the control surfaces to direct the aircraft in flight based on the modes selected on the Advanced Guidance Control System (AGSC) mode panel, and the flight path selected via the Navigation Control/Display Unit (NCDU).

  16. L(sub 1) Adaptive Flight Control System: Flight Evaluation and Technology Transition

    Science.gov (United States)

    Xargay, Enric; Hovakimyan, Naira; Dobrokhodov, Vladimir; Kaminer, Isaac; Gregory, Irene M.; Cao, Chengyu

    2010-01-01

    Certification of adaptive control technologies for both manned and unmanned aircraft represent a major challenge for current Verification and Validation techniques. A (missing) key step towards flight certification of adaptive flight control systems is the definition and development of analysis tools and methods to support Verification and Validation for nonlinear systems, similar to the procedures currently used for linear systems. In this paper, we describe and demonstrate the advantages of L(sub l) adaptive control architectures for closing some of the gaps in certification of adaptive flight control systems, which may facilitate the transition of adaptive control into military and commercial aerospace applications. As illustrative examples, we present the results of a piloted simulation evaluation on the NASA AirSTAR flight test vehicle, and results of an extensive flight test program conducted by the Naval Postgraduate School to demonstrate the advantages of L(sub l) adaptive control as a verifiable robust adaptive flight control system.

  17. Application of simple adaptive control to water hydraulic servo cylinder system

    Science.gov (United States)

    Ito, Kazuhisa; Yamada, Tsuyoshi; Ikeo, Shigeru; Takahashi, Koji

    2012-09-01

    Although conventional model reference adaptive control (MRAC) achieves good tracking performance for cylinder control, the controller structure is much more complicated and has less robustness to disturbance in real applications. This paper discusses the use of simple adaptive control (SAC) for positioning a water hydraulic servo cylinder system. Compared with MRAC, SAC has a simpler and lower order structure, i.e., higher feasibility. The control performance of SAC is examined and evaluated on a water hydraulic servo cylinder system. With the recent increased concerns over global environmental problems, the water hydraulic technique using pure tap water as a pressure medium has become a new drive source comparable to electric, oil hydraulic, and pneumatic drive systems. This technique is also preferred because of its high power density, high safety against fire hazards in production plants, and easy availability. However, the main problems for precise control in a water hydraulic system are steady state errors and overshoot due to its large friction torque and considerable leakage flow. MRAC has been already applied to compensate for these effects, and better control performances have been obtained. However, there have been no reports on the application of SAC for water hydraulics. To make clear the merits of SAC, the tracking control performance and robustness are discussed based on experimental results. SAC is confirmed to give better tracking performance compared with PI control, and a control precision comparable to MRAC (within 10 μm of the reference position) and higher robustness to parameter change, despite the simple controller. The research results ensure a wider application of simple adaptive control in real mechanical systems.

  18. Flight testing a propulsion-controlled aircraft emergency flight control system on an F-15 airplane

    Science.gov (United States)

    Burcham, F. W., Jr.; Burken, John; Maine, Trindel A.

    1994-01-01

    Flight tests of a propulsion-controlled aircraft (PCA) system on an F-15 airplane have been conducted at the NASA Dryden Flight Research Center. The airplane was flown with all flight control surfaces locked both in the manual throttles-only mode and in an augmented system mode. In the latter mode, pilot thumbwheel commands and aircraft feedback parameters were used to position the throttles. Flight evaluation results showed that the PCA system can be used to land an airplane that has suffered a major flight control system failure safely. The PCA system was used to recover the F-15 airplane from a severe upset condition, descend, and land. Pilots from NASA, U.S. Air Force, U.S. Navy, and McDonnell Douglas Aerospace evaluated the PCA system and were favorably impressed with its capability. Manual throttles-only approaches were unsuccessful. This paper describes the PCA system operation and testing. It also presents flight test results and pilot comments.

  19. Model-based nonlinear control of hydraulic servo systems: Challenges, developments and perspectives

    Science.gov (United States)

    Yao, Jianyong

    2018-06-01

    Hydraulic servo system plays a significant role in industries, and usually acts as a core point in control and power transmission. Although linear theory-based control methods have been well established, advanced controller design methods for hydraulic servo system to achieve high performance is still an unending pursuit along with the development of modern industry. Essential nonlinearity is a unique feature and makes model-based nonlinear control more attractive, due to benefit from prior knowledge of the servo valve controlled hydraulic system. In this paper, a discussion for challenges in model-based nonlinear control, latest developments and brief perspectives of hydraulic servo systems are presented: Modelling uncertainty in hydraulic system is a major challenge, which includes parametric uncertainty and time-varying disturbance; some specific requirements also arise ad hoc difficulties such as nonlinear friction during low velocity tracking, severe disturbance, periodic disturbance, etc.; to handle various challenges, nonlinear solutions including parameter adaptation, nonlinear robust control, state and disturbance observation, backstepping design and so on, are proposed and integrated, theoretical analysis and lots of applications reveal their powerful capability to solve pertinent problems; and at the end, some perspectives and associated research topics (measurement noise, constraints, inner valve dynamics, input nonlinearity, etc.) in nonlinear hydraulic servo control are briefly explored and discussed.

  20. Remote radio control of insect flight

    Directory of Open Access Journals (Sweden)

    Hirotaka Sato

    2009-10-01

    Full Text Available We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely-controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

  1. Remote radio control of insect flight.

    Science.gov (United States)

    Sato, Hirotaka; Berry, Christopher W; Peeri, Yoav; Baghoomian, Emen; Casey, Brendan E; Lavella, Gabriel; Vandenbrooks, John M; Harrison, Jon F; Maharbiz, Michel M

    2009-01-01

    We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

  2. Full-automatic Special Drill Hydraulic System and PLC Control

    Directory of Open Access Journals (Sweden)

    Tian Xue Jun

    2016-01-01

    Full Text Available A hydraulic-driven and PLC full-automatic special drill is introduced, working principle of the hydraulic system and PLC control system are analyzed and designed, this equipment has the advantages of high efficiency, superior quality and low cost etc.

  3. Hydraulic pitch control system for wind turbines: Advanced modeling and verification of an hydraulic accumulator

    DEFF Research Database (Denmark)

    Irizar, Victor; Andreasen, Casper Schousboe

    2017-01-01

    Hydraulic pitch systems provide robust and reliable control of power and speed of modern wind turbines. During emergency stops, where the pitch of the blades has to be taken to a full stop position to avoid over speed situations, hydraulic accumulators play a crucial role. Their efficiency...... and capability of providing enough energy to rotate the blades is affected by thermal processes due to the compression and decompression of the gas chamber. This paper presents an in depth study of the thermodynamical processes involved in an hydraulic accumulator during operation, and how they affect the energy...

  4. 14 CFR Appendix E to Part 135 - Helicopter Flight Recorder Specifications

    Science.gov (United States)

    2010-01-01

    ... Keying On-Off (Discrete) 1 0.25 sec Power in Each Engine: Free Power Turbine Speed and Engine Torque 0-130% (power Turbine Speed) Full range (Torque) ±2% 1 speed 1 torque (per engine) 0.2% 1 to 0.4% 1 Main... Hydraulic Pressure Low Discrete, each circuit 1 Flight Control Hydraulic Pressure Selector Switch Position...

  5. Virtual Design of a Controller for a Hydraulic Cam Phasing System

    Science.gov (United States)

    Schneider, Markus; Ulbrich, Heinz

    2010-09-01

    Hydraulic vane cam phasing systems are nowadays widely used for improving the performance of combustion engines. At stationary operation, these systems should achieve a constant phasing angle, which however is badly disturbed by the alternating torque generated by the valve actuation. As the hydraulic system shows a non-linear characteristic over the full operation range and the inductivity of the hydraulic pipes generates a significant time delay, a full model based control emerges very complex. Therefore a simple feed-forward controller is designed, bridging the time delay of the hydraulic system and improving the system behaviour significantly.

  6. Control of a hydraulically actuated continuously variable transmission

    NARCIS (Netherlands)

    Pesgens, M.F.M.; Vroemen, B.G.; Stouten, B.; Veldpaus, F.E.; Steinbuch, M.

    2006-01-01

    Vehicular drivelines with hierarchical powertrain control require good component controller tracking, enabling the main controller to reach the desired goals. This paper focuses on the development of a transmission ratio controller for a hydraulically actuated metal push-belt continuously variable

  7. Plug & Play Control of Hydraulic Networks

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard

    2012-01-01

    Process Control research program, which the work presented here is a part of. An industrial case study involving a large-scale hydraulic network with non-linear dynamics is studied. The hydraulic network underlies a district heating system, which provides heating water to a number of end-users in a city...... district. The case study considers a novel approach to the design of district heating systems in which the diameter of the pipes used in the system is reduced in order to reduce the heat losses in the system, thereby making it profitable to provide district heating to areas with low energy demands. The new...

  8. Advanced Transport Operating System (ATOPS) Flight Management/Flight Controls (FM/FC) software description

    Science.gov (United States)

    Wolverton, David A.; Dickson, Richard W.; Clinedinst, Winston C.; Slominski, Christopher J.

    1993-01-01

    The flight software developed for the Flight Management/Flight Controls (FM/FC) MicroVAX computer used on the Transport Systems Research Vehicle for Advanced Transport Operating Systems (ATOPS) research is described. The FM/FC software computes navigation position estimates, guidance commands, and those commands issued to the control surfaces to direct the aircraft in flight. Various modes of flight are provided for, ranging from computer assisted manual modes to fully automatic modes including automatic landing. A high-level system overview as well as a description of each software module comprising the system is provided. Digital systems diagrams are included for each major flight control component and selected flight management functions.

  9. 14 CFR 29.673 - Primary flight controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Primary flight controls. 29.673 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Control Systems § 29.673 Primary flight controls. Primary flight controls are those used by the pilot for immediate control of pitch, roll...

  10. 14 CFR 27.673 - Primary flight control.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Primary flight control. 27.673 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Control Systems § 27.673 Primary flight control. Primary flight controls are those used by the pilot for immediate control of pitch, roll...

  11. Regenerative Braking Control Strategy of Electric-Hydraulic Hybrid (EHH Vehicle

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2017-07-01

    Full Text Available A novel electric-hydraulic hybrid drivetrain incorporating a set of hydraulic systems is proposed for application in a pure electric vehicle. Models of the electric and hydraulic components are constructed. Two control strategies, which are based on two separate rules, are developed; the maximum energy recovery rate strategy adheres to the rule of the maximization of the braking energy recovery rate, while the minimum current impact strategy adheres to the rule of the minimization of the charge current to the battery. The simulation models were established to verify the effects of these two control strategies. An ABS (Anti-lock Braking System fuzzy control strategy is also developed and simulated. The simulation results demonstrate that the developed control strategy can effectively absorb the braking energy, suppress the current impact, and assure braking safety.

  12. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    Directory of Open Access Journals (Sweden)

    Ye HUANG

    2014-09-01

    Full Text Available Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under light loads and wearing of the variable-displacement pump. To overcome these shortcomings, this article designs a closed hydraulic control system in which an AC servo motor drives a quantitative pump that controls a spiral swinging hydraulic cylinder, and analyzes and calculates the structure and parameters of a spiral swinging hydraulic cylinder. The hydraulic system adjusts the servo motor’s speed according to the requirements of the control system, and the motor power matches the power provided to components, thus eliminating the throttling loss of hydraulic circuits. The system is compact, produces a large output force, provides stable transmission, has a quick response, and is suitable as a hydraulic control system of a large butterfly valve.

  13. Aircraft Hydraulic System Leakage Detection and Servicing Recommendations Method

    Science.gov (United States)

    2014-10-02

    ITA), Brazil. He is with Empresa Brasileira de Aeronáutica S.A (EMBRAER), São José dos Campos, SP, Brazil, since 2007. He works as a Development...degree in Control Engineering from Universidade Estadual de Campinas (Unicamp, 2004), Brazil, and a Master Degree in Aeronautical Engineering from...accumulators, filters, and consumers, that include all the actuators connected to the hydraulic power such as flight controls , brake and landing

  14. 14 CFR 23.673 - Primary flight controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Primary flight controls. 23.673 Section 23... Control Systems § 23.673 Primary flight controls. Primary flight controls are those used by the pilot for the immediate control of pitch, roll, and yaw. [Doc. No. 4080, 29 FR 17955, Dec. 18, 1964, as amended...

  15. Highly-Integrated Hydraulic Smart Actuators and Smart Manifolds for High-Bandwidth Force Control

    Directory of Open Access Journals (Sweden)

    Victor Barasuol

    2018-06-01

    Full Text Available Hydraulic actuation is the most widely used alternative to electric motors for legged robots and manipulators. It is often selected for its high power density, robustness and high-bandwidth control performance that allows the implementation of force/impedance control. Force control is crucial for robots that are in contact with the environment, since it enables the implementation of active impedance and whole body control that can lead to a better performance in known and unknown environments. This paper presents the hydraulic Integrated Smart Actuator (ISA developed by Moog in collaboration with IIT, as well as smart manifolds for rotary hydraulic actuators. The ISA consists of an additive-manufactured body containing a hydraulic cylinder, servo valve, pressure/position/load/temperature sensing, overload protection and electronics for control and communication. The ISA v2 and ISA v5 have been specifically designed to fit into the legs of IIT’s hydraulic quadruped robots HyQ and HyQ-REAL, respectively. The key features of these components tackle 3 of today’s main challenges of hydraulic actuation for legged robots through: (1 built-in controllers running inside integrated electronics for high-performance control, (2 low-leakage servo valves for reduced energy losses, and (3 compactness thanks to metal additive manufacturing. The main contributions of this paper are the derivation of the representative dynamic models of these highly integrated hydraulic servo actuators, a control architecture that allows for high-bandwidth force control and their experimental validation with application-specific trajectories and tests. We believe that this is the first work that presents additive-manufactured, highly integrated hydraulic smart actuators for robotics.

  16. Hydraulic engine valve actuation system including independent feedback control

    Science.gov (United States)

    Marriott, Craig D

    2013-06-04

    A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

  17. The Propulsive-Only Flight Control Problem

    Science.gov (United States)

    Blezad, Daniel J.

    1996-01-01

    Attitude control of aircraft using only the throttles is investigated. The long time constants of both the engines and of the aircraft dynamics, together with the coupling between longitudinal and lateral aircraft modes make piloted flight with failed control surfaces hazardous, especially when attempting to land. This research documents the results of in-flight operation using simulated failed flight controls and ground simulations of piloted propulsive-only control to touchdown. Augmentation control laws to assist the pilot are described using both optimal control and classical feedback methods. Piloted simulation using augmentation shows that simple and effective augmented control can be achieved in a wide variety of failed configurations.

  18. Adaptive fuzzy PID control of hydraulic servo control system for large axial flow compressor

    Science.gov (United States)

    Wang, Yannian; Wu, Peizhi; Liu, Chengtao

    2017-09-01

    To improve the stability of the large axial compressor, an efficient and special intelligent hydraulic servo control system is designed and implemented. The adaptive fuzzy PID control algorithm is used to control the position of the hydraulic servo cylinder steadily, which overcomes the drawback that the PID parameters should be adjusted based on the different applications. The simulation and the test results show that the system has a better dynamic property and a stable state performance.

  19. A Flight Control System Architecture for the NASA AirSTAR Flight Test Infrastructure

    Science.gov (United States)

    Murch, Austin M.

    2008-01-01

    A flight control system architecture for the NASA AirSTAR infrastructure has been designed to address the challenges associated with safe and efficient flight testing of research control laws in adverse flight conditions. The AirSTAR flight control system provides a flexible framework that enables NASA Aviation Safety Program research objectives, and includes the ability to rapidly integrate and test research control laws, emulate component or sensor failures, inject automated control surface perturbations, and provide a baseline control law for comparison to research control laws and to increase operational efficiency. The current baseline control law uses an angle of attack command augmentation system for the pitch axis and simple stability augmentation for the roll and yaw axes.

  20. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2011-01-01

    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable...

  1. 14 CFR 25.865 - Fire protection of flight controls, engine mounts, and other flight structure.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fire protection of flight controls, engine... Design and Construction Fire Protection § 25.865 Fire protection of flight controls, engine mounts, and other flight structure. Essential flight controls, engine mounts, and other flight structures located in...

  2. Robust hydraulic position controller by a fuzzy state controller

    International Nuclear Information System (INIS)

    Zhao, T.; Van der Wal, A.J.

    1994-01-01

    In nuclear industry, one of the most important design considerations of controllers is their robustness. Robustness in this context is defined as the ability of a system to be controlled in a stable way over a wide range of system parameters. Generally the systems to be controlled are linearized, and stability is subsequently proven for this idealized system. By combining classical control theory and fuzzy set theory, a new kind of state controller is proposed and successfully applied to a hydraulic position servo with excellent robustness against variation of system parameters

  3. Output Feedback Control of Electro-Hydraulic Cylinder Drives using the Twisting Algorithm

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2014-01-01

    contributions in literature. This paper considers the twisting algorithm when applied directly for output feedback control, and with the design based on a reduced order model representation of an arbitrary valve driven hydraulic cylinder drive. The consequence of implementing such a controller with the well......This paper discusses the utilization of the so-called twisting algorithm when applied in output feedback position control schemes for electro-hydraulic cylinder drives. The twisting controller was the first second order sliding controller ever introduced, and can structure-wise be considered...... feedback controller may be successfully applied to hydraulic valve driven cylinder drives, with performance being on the level with a conventional surface based first order sliding mode controller....

  4. Robust Decentralized Formation Flight Control

    Directory of Open Access Journals (Sweden)

    Zhao Weihua

    2011-01-01

    Full Text Available Motivated by the idea of multiplexed model predictive control (MMPC, this paper introduces a new framework for unmanned aerial vehicles (UAVs formation flight and coordination. Formulated using MMPC approach, the whole centralized formation flight system is considered as a linear periodic system with control inputs of each UAV subsystem as its periodic inputs. Divided into decentralized subsystems, the whole formation flight system is guaranteed stable if proper terminal cost and terminal constraints are added to each decentralized MPC formulation of the UAV subsystem. The decentralized robust MPC formulation for each UAV subsystem with bounded input disturbances and model uncertainties is also presented. Furthermore, an obstacle avoidance control scheme for any shape and size of obstacles, including the nonapriorily known ones, is integrated under the unified MPC framework. The results from simulations demonstrate that the proposed framework can successfully achieve robust collision-free formation flights.

  5. Controlling a negative loaded hydraulic cylinder using pressure feedback

    DEFF Research Database (Denmark)

    Hansen, M.R.; Andersen, T.O.

    2010-01-01

    This paper is concerned with the inherent oscillatory nature of pressure compensated velocity control of a hydraulic cylinder subjected to a negative load and suspended by means of an over-center valve. Initially, a linearized stability analysis of such a hydraulic circuit is carried out clearly ...... in a nonlinear time domain simulation model validating the linear stability analysis....

  6. Integrated Neural Flight and Propulsion Control System

    Science.gov (United States)

    Kaneshige, John; Gundy-Burlet, Karen; Norvig, Peter (Technical Monitor)

    2001-01-01

    This paper describes an integrated neural flight and propulsion control system. which uses a neural network based approach for applying alternate sources of control power in the presence of damage or failures. Under normal operating conditions, the system utilizes conventional flight control surfaces. Neural networks are used to provide consistent handling qualities across flight conditions and for different aircraft configurations. Under damage or failure conditions, the system may utilize unconventional flight control surface allocations, along with integrated propulsion control, when additional control power is necessary for achieving desired flight control performance. In this case, neural networks are used to adapt to changes in aircraft dynamics and control allocation schemes. Of significant importance here is the fact that this system can operate without emergency or backup flight control mode operations. An additional advantage is that this system can utilize, but does not require, fault detection and isolation information or explicit parameter identification. Piloted simulation studies were performed on a commercial transport aircraft simulator. Subjects included both NASA test pilots and commercial airline crews. Results demonstrate the potential for improving handing qualities and significantly increasing survivability rates under various simulated failure conditions.

  7. A Generic Model Based Tracking Controller for Hydraulic Valve-Cylinder Drives

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Schmidt, Lasse; Pedersen, Henrik Clemmensen

    2016-01-01

    in the entire range of operation, rather than reducing stationary errors, and may be parameterized from the desired gain margin, as well as linear model parameters. The proposed control design approaches are evaluated in an experimentally validated, nonlinear simulation model of a hydraulic valve-cylinder drive......The control of hydraulic valve-cylinder drives is still an active subject of research, and various linear and particularly nonlinear approaches has been proposed, especially in the last two-three decades. In many cases the proposed controllers appear to produce excellent tracking ability due...... generally has failed to break through in industry. This paper discusses the dominant properties necessary to take into account when considering position tracking control of hydraulic valve-cylinder drives, and presents two generally applicable, generic control design approaches that combines non...

  8. A Design to Digitalize Hydraulic Cylinder Control of a Machine Tool ...

    African Journals Online (AJOL)

    Conventionally hydraulic piston - cylinder servos are actuated using analogue controls for machine tool axis drives. In this paper a design of the axis control system of an NC milling machine which employs a small stepping motor to digitally actuated hydraulic piston - cylinder servo drives existing on the machines Y-axis is ...

  9. Knowledge-based Adaptive Tracking Control of Electro-hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Hansen, Poul Erik

    1997-01-01

    The paper deal with intelligent motion control and electro-hydraulic actuator systems for multiaxis machynes and robots.The research results are from the IMCIA research Programme supported by the Danish Technical Research Council, STVF.......The paper deal with intelligent motion control and electro-hydraulic actuator systems for multiaxis machynes and robots.The research results are from the IMCIA research Programme supported by the Danish Technical Research Council, STVF....

  10. Modeling and control of a hybrid wind-tidal turbine with hydraulic accumulator

    International Nuclear Information System (INIS)

    Fan, YaJun; Mu, AnLe; Ma, Tao

    2016-01-01

    This paper presents the modeling and control of a hybrid wind-tidal turbine with hydraulic accumulator. The hybrid turbine captures the offshore wind energy and tidal current energy simultaneously and stores the excess energy in hydraulic accumulator prior to electricity generation. Two hydraulic pumps installed respectively in wind and tidal turbine nacelles are used to transform the captured mechanical energy into hydraulic energy. To extract the maximal power from wind and tidal current, standard torque controls are achieved by regulating the displacements of the hydraulic pumps. To meet the output power demand, a Proportion Integration Differentiation (PID) controller is designed to distribute the hydraulic energy between the accumulator and the Pelton turbine. A simulation case study based on combining a 5 MW offshore wind turbine and a 1 MW tidal current turbine is undertaken. Case study demonstrates that the hybrid generation system not only captures all the available wind and tidal energy and also delivers the desired generator power precisely through the accumulator damping out all the power fluctuations from the wind and tidal speed disturbances. Energy and exergy analyses show that the energy efficiency can exceed 100% as the small input speeds are considered, and the exergy efficiency has the consistent change trends with demand power. Further more parametric sensitivity study on hydraulic accumulator shows that there is an inversely proportional relationship between accumulator and hydraulic equipments including the pump and nozzle in terms of dimensions. - Highlights: • A hybrid wind-tidal turbine is presented. • Hydraulic accumulator stores/releases the surplus energy. • Standard torque controls extract the maximal power from wind and tidal. • Generator outputs meet the electricity demand precisely. • Parametric sensitivity study on accumulator is implemented.

  11. Nonlinear adaptive robust back stepping force control of hydraulic load simulator: Theory and experiments

    International Nuclear Information System (INIS)

    Yao, Jianyong; Jiao, Zongxia; Yao, Bin

    2014-01-01

    High performance robust force control of hydraulic load simulator with constant but unknown hydraulic parameters is considered. In contrast to the linear control based on hydraulic linearization equations, hydraulic inherent nonlinear properties and uncertainties make the conventional feedback proportional-integral-derivative (PID) control not yield to high performance requirements. Furthermore, the hydraulic system may be subjected to non-smooth and discontinuous nonlinearities due to the directional change of valve opening. In this paper, based on a nonlinear system model of hydraulic load simulator, a discontinuous projection-based nonlinear adaptive robust back stepping controller is developed with servo valve dynamics. The proposed controller constructs a novel stable adaptive controller and adaptation laws with additional pressure dynamic related unknown parameters, which can compensate for the system nonlinearities and uncertain parameters, meanwhile a well-designed robust controller is also synthesized to dominate the model uncertainties coming from both parametric uncertainties and uncertain nonlinearities including unmodeled and ignored system dynamics. The controller theoretically guarantee a prescribed transient performance and final tracking accuracy in presence of both parametric uncertainties and uncertain nonlinearities; while achieving asymptotic output tracking in the absence of unstructured uncertainties. The implementation issues are also discussed for controller simplification. Some comparative results are obtained to verify the high-performance nature of the proposed controller.

  12. Nonlinear adaptive robust back stepping force control of hydraulic load simulator: Theory and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jianyong [Nanjing University of Science and Technology, Nanjing (China); Jiao, Zongxia [Beihang University, Beijing (China); Yao, Bin [Purdue University, West Lafayette (United States)

    2014-04-15

    High performance robust force control of hydraulic load simulator with constant but unknown hydraulic parameters is considered. In contrast to the linear control based on hydraulic linearization equations, hydraulic inherent nonlinear properties and uncertainties make the conventional feedback proportional-integral-derivative (PID) control not yield to high performance requirements. Furthermore, the hydraulic system may be subjected to non-smooth and discontinuous nonlinearities due to the directional change of valve opening. In this paper, based on a nonlinear system model of hydraulic load simulator, a discontinuous projection-based nonlinear adaptive robust back stepping controller is developed with servo valve dynamics. The proposed controller constructs a novel stable adaptive controller and adaptation laws with additional pressure dynamic related unknown parameters, which can compensate for the system nonlinearities and uncertain parameters, meanwhile a well-designed robust controller is also synthesized to dominate the model uncertainties coming from both parametric uncertainties and uncertain nonlinearities including unmodeled and ignored system dynamics. The controller theoretically guarantee a prescribed transient performance and final tracking accuracy in presence of both parametric uncertainties and uncertain nonlinearities; while achieving asymptotic output tracking in the absence of unstructured uncertainties. The implementation issues are also discussed for controller simplification. Some comparative results are obtained to verify the high-performance nature of the proposed controller.

  13. 14 CFR 23.865 - Fire protection of flight controls, engine mounts, and other flight structure.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fire protection of flight controls, engine... controls, engine mounts, and other flight structure. Flight controls, engine mounts, and other flight... they are capable of withstanding the effects of a fire. Engine vibration isolators must incorporate...

  14. Flight Test Approach to Adaptive Control Research

    Science.gov (United States)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  15. An electro-hydraulic servo control system research for CFETR blanket RH

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Changqi [Hefei University of Technology, Hefei 230009, Anhui (China); Tang, Hongjun, E-mail: taurustang@126.com [Hefei University of Technology, Hefei 230009, Anhui (China); Qi, Songsong [Hefei University of Technology, Hefei 230009, Anhui (China); Cheng, Yong; Feng, Hansheng; Peng, Xuebing; Song, Yuntao [Institute of Plasma Physics Chinese Academy of Sciences, Hefei 230031, Anhui (China)

    2014-11-15

    Highlights: • We discussed the conceptual design of CFETR blanket RH maintenance system. • The mathematical model of electro-hydraulic servo system was calculated. • A fuzzy adaptive PD controller was designed based on control theory and experience. • The co-simulation models of the system were established with AMESim/Simulink. • The fuzzy adaptive PD algorithm was designed as the core strategy of the system. - Abstract: Based on the technical design requirements of China Fusion Engineering Test Reactor (CFETR) blanket remote handling (RH) maintenance, this paper focus on the control method of achieving high synchronization accuracy of electro-hydraulic servo system. Based on fuzzy control theory and practical experience, a fuzzy adaptive proportional-derivative (PD) controller was designed. Then a more precise co-simulation model was established with AMESim/Simulink. Through the analysis of simulation results, a fuzzy adaptive PD control algorithm was designed as the core strategy of electro-hydraulic servo control system.

  16. An electro-hydraulic servo control system research for CFETR blanket RH

    International Nuclear Information System (INIS)

    Chen, Changqi; Tang, Hongjun; Qi, Songsong; Cheng, Yong; Feng, Hansheng; Peng, Xuebing; Song, Yuntao

    2014-01-01

    Highlights: • We discussed the conceptual design of CFETR blanket RH maintenance system. • The mathematical model of electro-hydraulic servo system was calculated. • A fuzzy adaptive PD controller was designed based on control theory and experience. • The co-simulation models of the system were established with AMESim/Simulink. • The fuzzy adaptive PD algorithm was designed as the core strategy of the system. - Abstract: Based on the technical design requirements of China Fusion Engineering Test Reactor (CFETR) blanket remote handling (RH) maintenance, this paper focus on the control method of achieving high synchronization accuracy of electro-hydraulic servo system. Based on fuzzy control theory and practical experience, a fuzzy adaptive proportional-derivative (PD) controller was designed. Then a more precise co-simulation model was established with AMESim/Simulink. Through the analysis of simulation results, a fuzzy adaptive PD control algorithm was designed as the core strategy of electro-hydraulic servo control system

  17. Research on intelligent algorithm of electro - hydraulic servo control system

    Science.gov (United States)

    Wang, Yannian; Zhao, Yuhui; Liu, Chengtao

    2017-09-01

    In order to adapt the nonlinear characteristics of the electro-hydraulic servo control system and the influence of complex interference in the industrial field, using a fuzzy PID switching learning algorithm is proposed and a fuzzy PID switching learning controller is designed and applied in the electro-hydraulic servo controller. The designed controller not only combines the advantages of the fuzzy control and PID control, but also introduces the learning algorithm into the switching function, which makes the learning of the three parameters in the switching function can avoid the instability of the system during the switching between the fuzzy control and PID control algorithms. It also makes the switch between these two control algorithm more smoother than that of the conventional fuzzy PID.

  18. Evidence for internal hydraulic control in the northern Øresund

    DEFF Research Database (Denmark)

    Nielsen, Morten Holtegaard

    2001-01-01

    are a contraction in the northern Oslashresund and the shallow Drogden sill at the entrance to the Baltic. The observations show that the two-layer flows through the contraction are often hydraulically controlled. The observations also reveal details of the transition from subcritical to supercritical flow...... to the strong influence of the Earth's rotation and the curvature of the streamlines. In the present study it is not attempted to explain these conditions, but the probable effects of rotation and curvature on the controlled flow rate are discussed briefly. Also, the possible effects of hydraulic control...

  19. Ares I Flight Control System Design

    Science.gov (United States)

    Jang, Jiann-Woei; Alaniz, Abran; Hall, Robert; Bedrossian, Nazareth; Hall, Charles; Ryan, Stephen; Jackson, Mark

    2010-01-01

    The Ares I launch vehicle represents a challenging flex-body structural environment for flight control system design. This paper presents a design methodology for employing numerical optimization to develop the Ares I flight control system. The design objectives include attitude tracking accuracy and robust stability with respect to rigid body dynamics, propellant slosh, and flex. Under the assumption that the Ares I time-varying dynamics and control system can be frozen over a short period of time, the flight controllers are designed to stabilize all selected frozen-time launch control systems in the presence of parametric uncertainty. Flex filters in the flight control system are designed to minimize the flex components in the error signals before they are sent to the attitude controller. To ensure adequate response to guidance command, step response specifications are introduced as constraints in the optimization problem. Imposing these constraints minimizes performance degradation caused by the addition of the flex filters. The first stage bending filter design achieves stability by adding lag to the first structural frequency to phase stabilize the first flex mode while gain stabilizing the higher modes. The upper stage bending filter design gain stabilizes all the flex bending modes. The flight control system designs provided here have been demonstrated to provide stable first and second stage control systems in both Draper Ares Stability Analysis Tool (ASAT) and the MSFC 6DOF nonlinear time domain simulation.

  20. Remotely Piloted Vehicles for Experimental Flight Control Testing

    Science.gov (United States)

    Motter, Mark A.; High, James W.

    2009-01-01

    A successful flight test and training campaign of the NASA Flying Controls Testbed was conducted at Naval Outlying Field, Webster Field, MD during 2008. Both the prop and jet-powered versions of the subscale, remotely piloted testbeds were used to test representative experimental flight controllers. These testbeds were developed by the Subsonic Fixed Wing Project s emphasis on new flight test techniques. The Subsonic Fixed Wing Project is under the Fundamental Aeronautics Program of NASA's Aeronautics Research Mission Directorate (ARMD). The purpose of these testbeds is to quickly and inexpensively evaluate advanced concepts and experimental flight controls, with applications to adaptive control, system identification, novel control effectors, correlation of subscale flight tests with wind tunnel results, and autonomous operations. Flight tests and operator training were conducted during four separate series of tests during April, May, June and August 2008. Experimental controllers were engaged and disengaged during fully autonomous flight in the designated test area. Flaps and landing gear were deployed by commands from the ground control station as unanticipated disturbances. The flight tests were performed NASA personnel with support from the Maritime Unmanned Development and Operations (MUDO) team of the Naval Air Warfare Center, Aircraft Division

  1. Development of hydraulic brake actuator for active brake control; Active brake seigyoyo yuatsu booster no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, Y; Hattori, M. Sugisawa, M.; Nishii, M [Aisin Seiki Co. Ltd., Aichi (Japan)

    1997-10-01

    Recently, application of active brake control systems of the vehicle are increasing. (Vehicle stability control, Panic brake assist ) We have developed a new hydraulic brake actuator for active brake control systems. New hydraulic brake actuator is composed of the three parts. (Hydraulic booster unit, Power supply unit, Control valve unit) This report describes the construction of the new hydraulic booster unit. 2 refs., 10 figs.

  2. Flight Control of Biomimetic Air Vehicles Using Vibrational Control and Averaging

    Science.gov (United States)

    Tahmasian, Sevak; Woolsey, Craig A.

    2017-08-01

    A combination of vibrational inputs and state feedback is applied to control the flight of a biomimetic air vehicle. First, a control strategy is developed for longitudinal flight, using a quasi-steady aerodynamic model and neglecting wing inertial effects. Vertical and forward motion is controlled by modulating the wings' stroke and feather angles, respectively. Stabilizing control parameter values are determined using the time-averaged dynamic model. Simulations of a system resembling a hawkmoth show that the proposed controller can overcome modeling error associated with the wing inertia and small parameter uncertainties when following a prescribed trajectory. After introducing the approach through an application to longitudinal flight, the control strategy is extended to address flight in three-dimensional space.

  3. Cascade Controller Including Back-stepping for Hydraulic-Mechanical Systems

    DEFF Research Database (Denmark)

    Choux, Martin; Hovland, Geir; Blanke, Mogens

    2012-01-01

    Development of a cascade controller structure including adaptive backstepping for a nonlinear hydraulic-mechanical system is considered in this paper where a dynamic friction (LuGre) model is included to obtain the necessary accuracy. The paper compares the performance of two variants of an adapt......Development of a cascade controller structure including adaptive backstepping for a nonlinear hydraulic-mechanical system is considered in this paper where a dynamic friction (LuGre) model is included to obtain the necessary accuracy. The paper compares the performance of two variants...... of an adaptive backstepping tracking controller with earlier results. The new control architecture is analysed and enhanced tracking performance is demonstrated when including the extended friction model. The complexity of the backstepping procedure is significantly reduced due to the cascade structure. Hence...

  4. Motion control of multi-actuator hydraulic systems for mobile machineries: Recent advancements and future trends

    Science.gov (United States)

    Xu, Bing; Cheng, Min

    2018-06-01

    This paper presents a survey of recent advancements and upcoming trends in motion control technologies employed in designing multi-actuator hydraulic systems for mobile machineries. Hydraulic systems have been extensively used in mobile machineries due to their superior power density and robustness. However, motion control technologies of multi-actuator hydraulic systems have faced increasing challenges due to stringent emission regulations. In this study, an overview of the evolution of existing throttling control technologies is presented, including open-center and load sensing controls. Recent advancements in energy-saving hydraulic technologies, such as individual metering, displacement, and hybrid controls, are briefly summarized. The impact of energy-saving hydraulic technologies on dynamic performance and control solutions are also discussed. Then, the advanced operation methods of multi-actuator mobile machineries are reviewed, including coordinated and haptic controls. Finally, challenges and opportunities of advanced motion control technologies are presented by providing an overall consideration of energy efficiency, controllability, cost, reliability, and other aspects.

  5. Adaptive Control System of Hydraulic Pressure Based on The Mathematical Modeling

    Science.gov (United States)

    Pilipenko, A. V.; Pilipenko, A. P.; Kanatnikov, N. V.

    2016-04-01

    In this paper, the authors highlight the problem of replacing an old heavy industrial equipment, and offer the replacement of obsolete control systems on the modern adaptive control system, which takes into account changes in the hydraulic system of the press and compensates them with a corrective action. The proposed system can reduce a water hammer and thereby increase the durability of the hydraulic system and tools.

  6. 14 CFR 121.543 - Flight crewmembers at controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight crewmembers at controls. 121.543... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.543 Flight crewmembers at controls. (a) Except as provided in paragraph (b) of this section, each required flight crewmember on...

  7. In-flight Fault Detection and Isolation in Aircraft Flight Control Systems

    Science.gov (United States)

    Azam, Mohammad; Pattipati, Krishna; Allanach, Jeffrey; Poll, Scott; Patterson-Hine, Ann

    2005-01-01

    In this paper we consider the problem of test design for real-time fault detection and isolation (FDI) in the flight control system of fixed-wing aircraft. We focus on the faults that are manifested in the control surface elements (e.g., aileron, elevator, rudder and stabilizer) of an aircraft. For demonstration purposes, we restrict our focus on the faults belonging to nine basic fault classes. The diagnostic tests are performed on the features extracted from fifty monitored system parameters. The proposed tests are able to uniquely isolate each of the faults at almost all severity levels. A neural network-based flight control simulator, FLTZ(Registered TradeMark), is used for the simulation of various faults in fixed-wing aircraft flight control systems for the purpose of FDI.

  8. Investigation of controlled flight into terrain : descriptions of flight paths for selected controlled flight into terrain (CFIT) aircraft accidents, 1985-1997

    Science.gov (United States)

    1999-03-01

    This report documents an investigation of the flight paths of 13 selected controlled flight into terrain (CFIT) aircraft accidents that occurred between 1985 and 1997. The Operations Assessment Division (DTS-43) and the Aviation Safety Division (DTS-...

  9. ACSYNT inner loop flight control design study

    Science.gov (United States)

    Bortins, Richard; Sorensen, John A.

    1993-01-01

    The NASA Ames Research Center developed the Aircraft Synthesis (ACSYNT) computer program to synthesize conceptual future aircraft designs and to evaluate critical performance metrics early in the design process before significant resources are committed and cost decisions made. ACSYNT uses steady-state performance metrics, such as aircraft range, payload, and fuel consumption, and static performance metrics, such as the control authority required for the takeoff rotation and for landing with an engine out, to evaluate conceptual aircraft designs. It can also optimize designs with respect to selected criteria and constraints. Many modern aircraft have stability provided by the flight control system rather than by the airframe. This may allow the aircraft designer to increase combat agility, or decrease trim drag, for increased range and payload. This strategy requires concurrent design of the airframe and the flight control system, making trade-offs of performance and dynamics during the earliest stages of design. ACSYNT presently lacks means to implement flight control system designs but research is being done to add methods for predicting rotational degrees of freedom and control effector performance. A software module to compute and analyze the dynamics of the aircraft and to compute feedback gains and analyze closed loop dynamics is required. The data gained from these analyses can then be fed back to the aircraft design process so that the effects of the flight control system and the airframe on aircraft performance can be included as design metrics. This report presents results of a feasibility study and the initial design work to add an inner loop flight control system (ILFCS) design capability to the stability and control module in ACSYNT. The overall objective is to provide a capability for concurrent design of the aircraft and its flight control system, and enable concept designers to improve performance by exploiting the interrelationships between

  10. Adaptive Flight Control Research at NASA

    Science.gov (United States)

    Motter, Mark A.

    2008-01-01

    A broad overview of current adaptive flight control research efforts at NASA is presented, as well as some more detailed discussion of selected specific approaches. The stated objective of the Integrated Resilient Aircraft Control Project, one of NASA s Aviation Safety programs, is to advance the state-of-the-art of adaptive controls as a design option to provide enhanced stability and maneuverability margins for safe landing in the presence of adverse conditions such as actuator or sensor failures. Under this project, a number of adaptive control approaches are being pursued, including neural networks and multiple models. Validation of all the adaptive control approaches will use not only traditional methods such as simulation, wind tunnel testing and manned flight tests, but will be augmented with recently developed capabilities in unmanned flight testing.

  11. Adaptive Sliding Mode Control for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper presents a new adaptive sliding mode controller generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The proposed control scheme requires limited knowledge on system parameters, and employs only piston- and valve spool position feedback...... employing parameter adaption through a recursive algorithm is presented. This is based on a reduced order model approximation of a VCD with unmatched valve flow- and cylinder asymmetries. Bounds on parameters are obtained despite lack of parameter knowledge, and the proposed controller demonstrates improved...

  12. 14 CFR Appendix F to Part 91 - Helicopter Flight Recorder Specifications

    Science.gov (United States)

    2010-01-01

    ..., Each Engine Main Rotor Speed Maximum Range ±5% 1 1%2. Free or Power Turbine Maximum Range ±5% 1 1%2. Engine Torque Maximum Range ±5% 1 1%2. Flight Control Hydraulic Pressure Primary (Discrete) High/Low 1...

  13. Online Learning Flight Control for Intelligent Flight Control Systems (IFCS)

    Science.gov (United States)

    Niewoehner, Kevin R.; Carter, John (Technical Monitor)

    2001-01-01

    The research accomplishments for the cooperative agreement 'Online Learning Flight Control for Intelligent Flight Control Systems (IFCS)' include the following: (1) previous IFC program data collection and analysis; (2) IFC program support site (configured IFC systems support network, configured Tornado/VxWorks OS development system, made Configuration and Documentation Management Systems Internet accessible); (3) Airborne Research Test Systems (ARTS) II Hardware (developed hardware requirements specification, developing environmental testing requirements, hardware design, and hardware design development); (4) ARTS II software development laboratory unit (procurement of lab style hardware, configured lab style hardware, and designed interface module equivalent to ARTS II faceplate); (5) program support documentation (developed software development plan, configuration management plan, and software verification and validation plan); (6) LWR algorithm analysis (performed timing and profiling on algorithm); (7) pre-trained neural network analysis; (8) Dynamic Cell Structures (DCS) Neural Network Analysis (performing timing and profiling on algorithm); and (9) conducted technical interchange and quarterly meetings to define IFC research goals.

  14. Manual Manipulation of Engine Throttles for Emergency Flight Control

    Science.gov (United States)

    Burcham, Frank W., Jr.; Fullerton, C. Gordon; Maine, Trindel A.

    2004-01-01

    If normal aircraft flight controls are lost, emergency flight control may be attempted using only engines thrust. Collective thrust is used to control flightpath, and differential thrust is used to control bank angle. Flight test and simulation results on many airplanes have shown that pilot manipulation of throttles is usually adequate to maintain up-and-away flight, but is most often not capable of providing safe landings. There are techniques that will improve control and increase the chances of a survivable landing. This paper reviews the principles of throttles-only control (TOC), a history of accidents or incidents in which some or all flight controls were lost, manual TOC results for a wide range of airplanes from simulation and flight, and suggested techniques for flying with throttles only and making a survivable landing.

  15. F-16XL ship #1 (#849) during first flight of the Digital Flight Control System (DFCS)

    Science.gov (United States)

    1997-01-01

    After completing its first flight with the Digital Flight Control System on December 16, 1997, the F-16XL #1 aircraft began a series of envelope expansion flights. On January 27 and 29, 1998, it successfully completed structural clearance tests, as well as most of the load testing Only flights at Mach 1.05 at 10,000 feet, Mach 1.1 at 15,000 feet, and Mach 1.2 at 20,000 feet remained. During the next flight, on February 4, an instrumentation problem cut short the planned envelope expansion tests. After the problem was corrected, the F-16XL returned to flight status, and on February 18 and 20, flight control and evaluation flights were made. Two more research flights were planned for the following week, but another problem appeared. During the ground start up, project personnel noticed that the leading edge flap moved without being commanded. The Digital Flight Control Computer was sent to the Lockheed-Martin facility at Fort Worth, where the problem was traced to a defective chip in the computer. After it was replaced, the F-16XL #1 flew a highly successful flight controls and handling qualities evaluation flight on March 26, clearing the way for the final tests. The final limited loads expansion flight occurred on March 31, and was fully successful. As a result, the on-site Lockheed-Martin loads engineer cleared the aircraft to Mach 1.8. The remaining two handling qualities and flight control evaluation flights were both made on April 3, 1998. These three flights concluded the flight test portion of the DFCS upgrade.

  16. Flight Control Laws for NASA's Hyper-X Research Vehicle

    Science.gov (United States)

    Davidson, J.; Lallman, F.; McMinn, J. D.; Martin, J.; Pahle, J.; Stephenson, M.; Selmon, J.; Bose, D.

    1999-01-01

    The goal of the Hyper-X program is to demonstrate and validate technology for design and performance predictions of hypersonic aircraft with an airframe-integrated supersonic-combustion ramjet propulsion system. Accomplishing this goal requires flight demonstration of a hydrogen-fueled scramjet powered hypersonic aircraft. A key enabling technology for this flight demonstration is flight controls. Closed-loop flight control is required to enable a successful stage separation, to achieve and maintain the design condition during the engine test, and to provide a controlled descent. Before the contract award, NASA developed preliminary flight control laws for the Hyper-X to evaluate the feasibility of the proposed scramjet test sequence and descent trajectory. After the contract award, a Boeing/NASA partnership worked to develop the current control laws. This paper presents a description of the Hyper-X Research Vehicle control law architectures with performance and robustness analyses. Assessments of simulated flight trajectories and stability margin analyses demonstrate that these control laws meet the flight test requirements.

  17. UIO-based Fault Diagnosis for Hydraulic Automatic Gauge Control System of Magnesium Sheet Mill

    Directory of Open Access Journals (Sweden)

    Li-Ping FAN

    2014-02-01

    Full Text Available Hydraulic automatic gauge control system of magnesium sheet mill is a complex integrated control system, which including mechanical, hydraulic and electrical comprehensive information. The failure rate of AGC system always is high, and its fault reasons are always complex. Based on analyzing the fault of main components of the automatic gauge control system, unknown input observer is used to realize fault diagnosis and isolation. Simulation results show that the fault diagnosis method based on the unknown input observer for the hydraulic automatic gauge control system of magnesium sheet mill is effective.

  18. Design techniques for mutlivariable flight control systems

    Science.gov (United States)

    1981-01-01

    Techniques which address the multi-input closely coupled nature of advanced flight control applications and digital implementation issues are described and illustrated through flight control examples. The techniques described seek to exploit the advantages of traditional techniques in treating conventional feedback control design specifications and the simplicity of modern approaches for multivariable control system design.

  19. Life-critical digital flight control systems

    Science.gov (United States)

    Mcwha, James

    1990-01-01

    Digital autopilot systems were first used on commercial airplanes in the late 1970s. The A-320 airplane was the first air transport airplane with a fly-by-wire primary flight control system. On the 767-X (777) airplane Boeing will install all fly-by-wire flight controls. Activities related to safety, industry status and program phases are discussed.

  20. Development of Proportional Pressure Control Valve for Hydraulic Braking Actuator of Automobile ABS

    Directory of Open Access Journals (Sweden)

    Che-Pin Chen

    2018-04-01

    Full Text Available This research developed a novel proportional pressure control valve for an automobile hydraulic braking actuator. It also analyzed and simulated solenoid force of the control valves, and the pressure relief capability test of electromagnetic thrust with the proportional valve body. Considering the high controllability and ease of production, the driver of this proportional valve was designed with a small volume and powerful solenoid force to control braking pressure and flow. Since the proportional valve can have closed-loop control, the proportional valve can replace a conventional solenoid valve in current brake actuators. With the proportional valve controlling braking and pressure relief mode, it can narrow the space of hydraulic braking actuator, and precisely control braking force to achieve safety objectives. Finally, the proposed novel proportional pressure control valve of an automobile hydraulic braking actuator was implemented and verified experimentally.

  1. Integrated flight path planning system and flight control system for unmanned helicopters.

    Science.gov (United States)

    Jan, Shau Shiun; Lin, Yu Hsiang

    2011-01-01

    This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM).

  2. Integrated Flight Path Planning System and Flight Control System for Unmanned Helicopters

    Science.gov (United States)

    Jan, Shau Shiun; Lin, Yu Hsiang

    2011-01-01

    This paper focuses on the design of an integrated navigation and guidance system for unmanned helicopters. The integrated navigation system comprises two systems: the Flight Path Planning System (FPPS) and the Flight Control System (FCS). The FPPS finds the shortest flight path by the A-Star (A*) algorithm in an adaptive manner for different flight conditions, and the FPPS can add a forbidden zone to stop the unmanned helicopter from crossing over into dangerous areas. In this paper, the FPPS computation time is reduced by the multi-resolution scheme, and the flight path quality is improved by the path smoothing methods. Meanwhile, the FCS includes the fuzzy inference systems (FISs) based on the fuzzy logic. By using expert knowledge and experience to train the FIS, the controller can operate the unmanned helicopter without dynamic models. The integrated system of the FPPS and the FCS is aimed at providing navigation and guidance to the mission destination and it is implemented by coupling the flight simulation software, X-Plane, and the computing software, MATLAB. Simulations are performed and shown in real time three-dimensional animations. Finally, the integrated system is demonstrated to work successfully in controlling the unmanned helicopter to operate in various terrains of a digital elevation model (DEM). PMID:22164029

  3. A unified flight control methodology for a compound rotorcraft in fundamental and aerobatic maneuvering flight

    Science.gov (United States)

    Thorsen, Adam

    This study investigates a novel approach to flight control for a compound rotorcraft in a variety of maneuvers ranging from fundamental to aerobatic in nature. Fundamental maneuvers are a class of maneuvers with design significance that are useful for testing and tuning flight control systems along with uncovering control law deficiencies. Aerobatic maneuvers are a class of aggressive and complex maneuvers with more operational significance. The process culminating in a unified approach to flight control includes various control allocation studies for redundant controls in trim and maneuvering flight, an efficient methodology to simulate non-piloted maneuvers with varying degrees of complexity, and the setup of an unconventional control inceptor configuration along with the use of a flight simulator to gather pilot feedback in order to improve the unified control architecture. A flight path generation algorithm was developed to calculate control inceptor commands required for a rotorcraft in aerobatic maneuvers. This generalized algorithm was tailored to generate flight paths through optimization methods in order to satisfy target terminal position coordinates or to minimize the total time of a particular maneuver. Six aerobatic maneuvers were developed drawing inspiration from air combat maneuvers of fighter jet aircraft: Pitch-Back Turn (PBT), Combat Ascent Turn (CAT), Combat Descent Turn (CDT), Weaving Pull-up (WPU), Combat Break Turn (CBT), and Zoom and Boom (ZAB). These aerobatic maneuvers were simulated at moderate to high advance ratios while fundamental maneuvers of the compound including level accelerations/decelerations, climbs, descents, and turns were investigated across the entire flight envelope to evaluate controller performance. The unified control system was developed to allow controls to seamlessly transition between manual and automatic allocations while ensuring that the axis of control for a particular inceptor remained constant with flight

  4. Flight test trajectory control analysis

    Science.gov (United States)

    Walker, R.; Gupta, N.

    1983-01-01

    Recent extensions to optimal control theory applied to meaningful linear models with sufficiently flexible software tools provide powerful techniques for designing flight test trajectory controllers (FTTCs). This report describes the principal steps for systematic development of flight trajectory controllers, which can be summarized as planning, modeling, designing, and validating a trajectory controller. The techniques have been kept as general as possible and should apply to a wide range of problems where quantities must be computed and displayed to a pilot to improve pilot effectiveness and to reduce workload and fatigue. To illustrate the approach, a detailed trajectory guidance law is developed and demonstrated for the F-15 aircraft flying the zoom-and-pushover maneuver.

  5. Project calculation of the steering mechanism hydraulic servo control in motor vehicles

    Directory of Open Access Journals (Sweden)

    Zoran Đukan Majkić

    2013-10-01

    Full Text Available Hydraulic servo controls are designed to facilitate rotation in place without providing increased ppower to steering wheels. In the initial design phase, the dimensions required for control systems are usually obtained through the calculation of their load when wheels rotate in place, where the torque is calculated empirically. The starting point in the project calculation is thus to determine the hydraulic power steering torque torsional resistance which is then used to determine the maximum value of force i.e. the torque on the stering wheel. The calculation of the control system servo control consists of determining the basic parameters, the required pump capacity, the main dimensions of the hub and the  pipeline and the conditions for the stability of the system control mechanism. Introduction The aim of the calculation of the steering control system is to determine the basic parameters of its components which ensure the fulfilment of requirements of the control system. Calculations are performed in several stages with a simultaneous  detailed constructive analysis of the control system leading to the best variant. At each stage, design and control calculations of the hydraulic servo of the steering mechanism are performed. The design allows the computation to complete the selection of basic dimensions of the amplifer elements, starting from the approved scheme and the basic building loads of approximate values. Calculations control is carried out to clarify the structural solution and to obtain the output characteristics of the control amplifier which are applied in the  estimation of  potential properties of the structure. Project calculation Baseline data must be sufficiently reliable, ie. must correspond to the construction characteristics of the vehicle design and the control system as well as to service conditions..A proper deterimination of the torque calculation of torsional resistance in wheels is of utmost importance. Moment of

  6. F-15 IFCS: Intelligent Flight Control System

    Science.gov (United States)

    Bosworth, John

    2007-01-01

    This viewgraph presentation describes the F-15 Intelligent Flight Control System (IFCS). The goals of this project include: 1) Demonstrate revolutionary control approaches that can efficiently optimize aircraft performance in both normal and failure conditions; and 2) Demonstrate advance neural network-based flight control technology for new aerospace systems designs.

  7. In-flight cabin smoke control.

    Science.gov (United States)

    Eklund, T I

    1996-12-31

    Fatal accidents originating from in-flight cabin fires comprise only about 1% of all fatal accidents in the civil jet transport fleet. Nevertheless, the impossibility of escape during flight accentuates the hazards resulting from low visibility and toxic gases. Control of combustion products in an aircraft cabin is affected by several characteristics that make the aircraft cabin environment unique. The aircraft fuselage is pressurized in flight and has an air distribution system which provides ventilation jets from the ceiling level air inlets running along the cabin length. A fixed quantity of ventilation air is metered into the cabin and air discharge is handled primarily by pressure controlling outflow valves in the rear lower part of the fuselage. Earlier airplane flight tests on cabin smoke control used generators producing minimally buoyant smoke products that moved with and served as a telltales for overall cabin ventilation flows. Analytical studies were done with localized smoke production to predict the percent of cabin length that would remain smoke-free during continuous generation. Development of a buoyant smoke generator allowed simulation of a fire plume with controllable simulated temperature and heat release rates. Tests on a Boeing 757, modified to allow smoke venting out through the top of the cabin, showed that the buoyant smoke front moved at 0.46m/s (1.5ft/sec) with and 0.27m/sec (0.9ft/sec) against, the axial ventilation airflow. Flight tests in a modified Boeing 727 showed that a ceiling level counterflow of about 0.55m/sec (1.8ft/sec) was required to arrest the forward movement of buoyant smoke. A design goal of 0.61m/s (2ft/sec) axial cabin flow would require a flow rate of 99m3/min (3500ft3/min) in a furnished Boeing 757. The current maximum fresh air cabin ventilation flow is 78m3/min (2756 ft3/min). Experimental results indicate that buoyancy effects cause smoke movement behaviour that is not predicted by traditional design analyses and

  8. Tracking control of the hydraulically actuated flexible manipulator

    International Nuclear Information System (INIS)

    Kwon, D.S.; Babcock, S.M.; Burks, B.L.; Kress, R.L.

    1995-01-01

    The remediation of single-shell radioactive waste storage tanks is one of the urgent tasks of the Department of Energy that challenge state-of-the-art equipment and methods. The use of long-reach manipulators is being seriously considered for this remediation task. Because high payload capacity and high length-to-cross-section ratio requirements, these long-reach manipulator systems are expected to use hydraulic actuators and to exhibit significant structural flexibility. The controller has been designed to compensate for the hydraulic actuator dynamics by using a load-compensated velocity feedforward loop and to increase the bandwidth by using a pressure feed backloop. Shaping filter techniques have been applied as a feedforward controller to avoid structural vibrations during operation. Among various types of shaping filter methods investigated an approach, referred to as a ''feedforward simulation filter'' that uses embedded simulation, has been presented

  9. Hybrid Adaptive Flight Control with Model Inversion Adaptation

    Science.gov (United States)

    Nguyen, Nhan

    2011-01-01

    This study investigates a hybrid adaptive flight control method as a design possibility for a flight control system that can enable an effective adaptation strategy to deal with off-nominal flight conditions. The hybrid adaptive control blends both direct and indirect adaptive control in a model inversion flight control architecture. The blending of both direct and indirect adaptive control provides a much more flexible and effective adaptive flight control architecture than that with either direct or indirect adaptive control alone. The indirect adaptive control is used to update the model inversion controller by an on-line parameter estimation of uncertain plant dynamics based on two methods. The first parameter estimation method is an indirect adaptive law based on the Lyapunov theory, and the second method is a recursive least-squares indirect adaptive law. The model inversion controller is therefore made to adapt to changes in the plant dynamics due to uncertainty. As a result, the modeling error is reduced that directly leads to a decrease in the tracking error. In conjunction with the indirect adaptive control that updates the model inversion controller, a direct adaptive control is implemented as an augmented command to further reduce any residual tracking error that is not entirely eliminated by the indirect adaptive control.

  10. Aircraft digital flight control technical review

    Science.gov (United States)

    Davenport, Otha B.; Leggett, David B.

    1993-01-01

    The Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems. Consequently, a technical review team was formed to examine the development process and determine why PIO problems continued to occur. The team was also to identify the 'best practices' used in the various programs. The charter of the team was to focus on the PIO problem, assess the current development process, and document the 'best practices.' The team reviewed all major USAF aircraft programs with digital flight controls, specifically, the F-15E, F-16C/D, F-22, F-111, C-17, and B-2. The team interviewed contractor, System Program Office (SPO), and Combined Test Force (CTF) personnel on these programs. The team also went to NAS Patuxent River to interview USN personnel about the F/A-18 program. The team also reviewed experimental USAF and NASA systems with digital flight control systems: X-29, X-31, F-15 STOL and Maneuver Technology Demonstrator (SMTD), and the Variable In-Flight Stability Test Aircraft (VISTA). The team also discussed the problem with other experts in the field including Ralph Smith and personnel from Calspan. The major conclusions and recommendations from the review are presented.

  11. Electro-Pneumatic Control System with Hydraulically Positioning Actuator Motor

    Directory of Open Access Journals (Sweden)

    V. N. Pilgunov

    2016-01-01

    Full Text Available A compressibility of the actuating fluid of a pneumatic drive (compressed air leads to significant landing of the pneumatic cylinder piston at the time of stop and hold of the load, a constant component of which can fluctuate significantly for the holding period.There are a lot of factors, which have a significant impact on the landing value of piston. Those are: an initial position of the piston at its stop, which determines the volume of the an active area of the piston, a value of the constant load component at the time of stop and its variation for the holding period, a transfer coefficient of the position component of the load, an active area of the pneumatic cylinder piston, as well as reduction in atmospheric pressure, which can significantly affect the operation of the control systems of small aircrafts flying at high altitudes.To reduce the landing value of piston due to changing value of the constant load component for its holding period, it is proposed to use a hydraulic positioner, which comprises a hydraulic cylinder the rod of which is rigidly connected to the rod of the pneumatic cylinder through the traverse, a cross-feed valve of the hydro-cylinder cavities with discrete electro-magnetic control, and adjustable chokes.A programmable logic controller provides the hydraulic positioner control. At the moment the piston stops and the load is held the cross-feed valve overlaps the hydro-cylinder cavities thereby locking the pneumatic cylinder piston and preventing its landing. With available pneumatic cylinder-controlled signal the cross-feed valve connects the piston and rod cavities of the positioner hydro-cylinder, the pneumatic cylinder piston is released and becomes capable of moving.A numerical estimate of landing of the pneumatic cylinder piston and its positioning quality is of essential interest. For this purpose, a technique to calculate the landing of piston has been developed taking into consideration that different

  12. An overview of integrated flight-propulsion controls flight research on the NASA F-15 research airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Gatlin, Donald H.; Stewart, James F.

    1995-01-01

    The NASA Dryden Flight Research Center has been conducting integrated flight-propulsion control flight research using the NASA F-15 airplane for the past 12 years. The research began with the digital electronic engine control (DEEC) project, followed by the F100 Engine Model Derivative (EMD). HIDEC (Highly Integrated Digital Electronic Control) became the umbrella name for a series of experiments including: the Advanced Digital Engine Controls System (ADECS), a twin jet acoustics flight experiment, self-repairing flight control system (SRFCS), performance-seeking control (PSC), and propulsion controlled aircraft (PCA). The upcoming F-15 project is ACTIVE (Advanced Control Technology for Integrated Vehicles). This paper provides a brief summary of these activities and provides background for the PCA and PSC papers, and includes a bibliography of all papers and reports from the NASA F-15 project.

  13. Positive Exchange of Flight Controls Program

    Science.gov (United States)

    1995-03-10

    This advisory circular provides guidance for all pilots, especially student pilots, flight instructors, and pilot examiners, on the recommended procedure to use for the positive exchange of flight controls between pilots when operating an aircraft.

  14. Hydraulically centered control rod

    International Nuclear Information System (INIS)

    Horlacher, W.R.; Sampson, W.T.; Schukei, G.E.

    1981-01-01

    A control rod suspended to reciprocate in a guide tube of a nuclear fuel assembly has a hydraulic bearing formed at its lower tip. The bearing includes a plurality of discrete pockets on its outer surface into which a flow of liquid is continuously provided. In one embodiment the flow is induced by the pressure head in a downward facing chamber at the end of the bearing. In another embodiment the flow originates outside the guide tube. In both embodiments the flow into the pockets produces pressure differences across the bearing which counteract forces tending to drive the rod against the guide tube wall. Thus contact of the rod against the guide tube is avoided

  15. Underwater hydraulic shock shovel control system

    Science.gov (United States)

    Liu, He-Ping; Luo, A.-Ni; Xiao, Hai-Yan

    2008-06-01

    The control system determines the effectiveness of an underwater hydraulic shock shovel. This paper begins by analyzing the working principles of these shovels and explains the importance of their control systems. A new type of control system’s mathematical model was built and analyzed according to those principles. Since the initial control system’s response time could not fulfill the design requirements, a PID controller was added to the control system. System response time was still slower than required, so a neural network was added to nonlinearly regulate the proportional element, integral element and derivative element coefficients of the PID controller. After these improvements to the control system, system parameters fulfilled the design requirements. The working performance of electrically-controlled parts such as the rapidly moving high speed switch valve is largely determined by the control system. Normal control methods generally can’t satisfy a shovel’s requirements, so advanced and normal control methods were combined to improve the control system, bringing good results.

  16. Tubing Cutter is Activated Hydraulically

    Science.gov (United States)

    Mcsmith, D. G.; Richardson, J. I.

    1983-01-01

    Hydraulically-actuated tubing cutter severs tubing when operator squeezes handle grip. "Gooseneck" extension enables cutter to be used in areas where accessiblity is limited. Cutter has potential as flight-line tool and is useful in automobile and fire rescue work.

  17. Simulation of proportional control of hydraulic actuator using digital hydraulic valves

    Science.gov (United States)

    Raghuraman, D. R. S.; Senthil Kumar, S.; Kalaiarasan, G.

    2017-11-01

    Fluid power systems using oil hydraulics in earth moving and construction equipment have been using proportional and servo control valves for a long time to achieve precise and accurate position control backed by system performance. Such valves are having feedback control in them and exhibit good response, sensitivity and fine control of the actuators. Servo valves and proportional valves are possessing less hysteresis when compared to on-off type valves, but when the servo valve spools get stuck in one position, a high frequency called as jitter is employed to bring the spool back, whereas in on-off type valves it requires lesser technology to retract the spool. Hence on-off type valves are used in a technology known as digital valve technology, which caters to precise control on slow moving loads with fast switching times and with good flow and pressure control mimicking the performance of an equivalent “proportional valve” or “servo valve”.

  18. FRF based position controller design through system identification for A hydraulic cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyoung Kyu; Kim, Dong Hwan [Dept. of Mechanical Design and Robot Engineering, Seoul National University of Science and Technology, Seoul (Korea, Republic of); Park, Jong Won [Reliability Assessment Center, Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2015-11-15

    In this study, we have focused on the design of a controller and an operating program for the operation of the hydraulic actuators used in a shaker. To control the motion of the shaker accurately, the position of each hydraulic cylinder should be controlled precisely even under an uncertain environment. For this purpose, we have suggested a control algorithm using an FRF (frequency response function) based control which senses the behavior of the actuator in advance, calculates a transfer function through the system identification method, and provides the final control input. The experimental results on the performance of this system were compared with that of a simple PID control algorithm.

  19. 14 CFR 125.311 - Flight crewmembers at controls.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight crewmembers at controls. 125.311... CAPACITY OF 6,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Flight Operations § 125.311 Flight crewmembers at controls. (a) Except as provided in paragraph (b) of this section, each...

  20. Cosmonaut Dezhurov Talks With Flight Controllers

    Science.gov (United States)

    2001-01-01

    Aboard the International Space Station (ISS), Cosmonaut and Expedition Three flight engineer Vladimir N. Dezhurov, representing Rosaviakosmos, talks with flight controllers from the Zvezda Service Module. Russian-built Zvezda is linked to the Functional Cargo Block (FGB), or Zarya, the first component of the ISS. Zarya was launched on a Russian Proton rocket prior to the launch of Unity. The third component of the ISS, Zvezda (Russian word for star), the primary Russian contribution to the ISS, was launched by a three-stage Proton rocket on July 12, 2000. Zvezda serves as the cornerstone for early human habitation of the Station, providing living quarters, a life support system, electrical power distribution, a data processing system, flight control system, and propulsion system. It also provides a communications system that includes remote command capabilities from ground flight controllers. The 42,000-pound module measures 43 feet in length and has a wing span of 98 feet. Similar in layout to the core module of Russia's Mir space station, it contains 3 pressurized compartments and 13 windows that allow ultimate viewing of Earth and space.

  1. Evaluation of Linear and Non-Linear Control Schemes Applied to a Hydraulic Servo System

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Hansen, Michael Rygaard; Pedersen, Henrik Clemmensen

    2005-01-01

    Due to the innovation of low-cost electronics such as sensors, microcontrollers etc., the focus on highperformance motion control is increasing. This work focuses on position control of single-input single-output hydraulic servo-systems in general. A hydraulically actuated robotic manipulator...

  2. An Analytic Approach to Cascade Control Design for Hydraulic Valve-Cylinder Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Hansen, Anders Hedegaard; Andersen, Torben O.

    2016-01-01

    , unfortunately not present in valve-operated hydraulic drives. This paper considers a cascade control approach for hydraulic valve-cylinder drives motivated by the fact that this may be applied to successfully suppress nonlinearities. The drive is pre-compensated utilizing a pressure updated inverse valve flow...

  3. 76 FR 9265 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System: Control...

    Science.gov (United States)

    2011-02-17

    ...: Gulfstream Model GVI Airplane; Electronic Flight Control System: Control Surface Position Awareness AGENCY... for transport category airplanes. These design features include an electronic flight control system... Design Features The GVI has an electronic flight control system and no direct coupling from the cockpit...

  4. Preliminary Flight Results of a Fly-by-throttle Emergency Flight Control System on an F-15 Airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. Gordon; Wells, Edward A.

    1993-01-01

    A multi-engine aircraft, with some or all of the flight control system inoperative, may use engine thrust for control. NASA Dryden has conducted a study of the capability and techniques for this emergency flight control method for the F-15 airplane. With an augmented control system, engine thrust, along with appropriate feedback parameters, is used to control flightpath and bank angle. Extensive simulation studies were followed by flight tests. The principles of throttles only control, the F-15 airplane, the augmented system, and the flight results including actual landings with throttles-only control are discussed.

  5. 76 FR 31456 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System: Control...

    Science.gov (United States)

    2011-06-01

    ... electronic flight control system. The applicable airworthiness regulations do not contain adequate or... Design Features The Gulfstream Model GVI airplane has an electronic flight control system and no direct... impending control surface limiting, piloted or auto-flight system control of the airplane might be...

  6. Plant hydraulic controls over ecosystem responses to climate-enhanced disturbances

    Science.gov (United States)

    Mackay, D. S.; Ewers, B. E.; Reed, D. E.; Pendall, E.; McDowell, N. G.

    2012-12-01

    Climate-enhanced disturbances such as drought and insect infestation range in severity, contributing minor to severe stress to forests including forest mortality. While neither form of disturbance has been unambiguously implicated as a mechanism of mortality, both induce changes in water, carbon, and nutrient cycling that are key to understanding forest ecosystem response to, and recovery from, disturbance. Each disturbance type has different biophysical, ecohydrological, and biogeochemical signatures that potentially complicate interpretation and development of theory. Plant hydraulic function is arguably a unifying control over these responses to disturbance because it regulates stomatal conductance, leaf biochemistry, carbon (C) uptake and utilization, and nutrient cycling. We demonstrated this idea by focusing on water and C, including non-structural (NSC), resources, and nitrogen (N) uptake across a spectrum of forest ecosystems (e.g., northern temperate mixed forests, lodgepole pine forests in the Rocky Mountains, and pinon pine - juniper woodlands in New Mexico) using the Terrestrial Regional Ecosystem Exchange Simulator (TREES). TREES is grounded in the biophysics of water movement through soil and plants, respectively via hydraulic conductivity of the soil and cavitation of xylem. It combines this dynamic plant hydraulic conductance with canopy biochemical controls over photosynthesis, and the dynamics of structural and non-structural carbon through a carbon budget that responds to plant hydraulic status. As such, the model can be used to develop testable hypotheses on a multitude of disturbance and recovery responses including xylem dysfunction, stomatal and non-stomatal controls on photosynthesis and carbon allocation, respiration, and allocation to defense compounds. For each of the ecosystems we constrained and evaluated the model with allometry, sap flux and/or eddy covariance data, leaf gas exchange measurements, and vulnerability to cavitation data

  7. Production Support Flight Control Computers: Research Capability for F/A-18 Aircraft at Dryden Flight Research Center

    Science.gov (United States)

    Carter, John F.

    1997-01-01

    NASA Dryden Flight Research Center (DFRC) is working with the United States Navy to complete ground testing and initiate flight testing of a modified set of F/A-18 flight control computers. The Production Support Flight Control Computers (PSFCC) can give any fleet F/A-18 airplane an in-flight, pilot-selectable research control law capability. NASA DFRC can efficiently flight test the PSFCC for the following four reasons: (1) Six F/A-18 chase aircraft are available which could be used with the PSFCC; (2) An F/A-18 processor-in-the-loop simulation exists for validation testing; (3) The expertise has been developed in programming the research processor in the PSFCC; and (4) A well-defined process has been established for clearing flight control research projects for flight. This report presents a functional description of the PSFCC. Descriptions of the NASA DFRC facilities, PSFCC verification and validation process, and planned PSFCC projects are also provided.

  8. Reliability analysis of Airbus A-330 computer flight management system

    OpenAIRE

    Fajmut, Metod

    2010-01-01

    Diploma thesis deals with digitized, computerized flight control system »Fly-by-wire« and security aspects of the computer system of an aircraft Airbus A330. As for space and military aircraft structures is also in commercial airplanes, much of the financial contribution devoted to reliability. Conventional aircraft control systems have, and some are still, to rely on mechanical and hydraulic connections between the controls on aircraft operated by the pilot and control surfaces. But newer a...

  9. Engine including hydraulically actuated valvetrain and method of valve overlap control

    Science.gov (United States)

    Cowgill, Joel [White Lake, MI

    2012-05-08

    An exhaust valve control method may include displacing an exhaust valve in communication with the combustion chamber of an engine to an open position using a hydraulic exhaust valve actuation system and returning the exhaust valve to a closed position using the hydraulic exhaust valve actuation assembly. During closing, the exhaust valve may be displaced for a first duration from the open position to an intermediate closing position at a first velocity by operating the hydraulic exhaust valve actuation assembly in a first mode. The exhaust valve may be displaced for a second duration greater than the first duration from the intermediate closing position to a fully closed position at a second velocity at least eighty percent less than the first velocity by operating the hydraulic exhaust valve actuation assembly in a second mode.

  10. Pigeons (C. livia Follow Their Head during Turning Flight: Head Stabilization Underlies the Visual Control of Flight

    Directory of Open Access Journals (Sweden)

    Ivo G. Ros

    2017-12-01

    Full Text Available Similar flight control principles operate across insect and vertebrate fliers. These principles indicate that robust solutions have evolved to meet complex behavioral challenges. Following from studies of visual and cervical feedback control of flight in insects, we investigate the role of head stabilization in providing feedback cues for controlling turning flight in pigeons. Based on previous observations that the eyes of pigeons remain at relatively fixed orientations within the head during flight, we test potential sensory control inputs derived from head and body movements during 90° aerial turns. We observe that periods of angular head stabilization alternate with rapid head repositioning movements (head saccades, and confirm that control of head motion is decoupled from aerodynamic and inertial forces acting on the bird's continuously rotating body during turning flapping flight. Visual cues inferred from head saccades correlate with changes in flight trajectory; whereas the magnitude of neck bending predicts angular changes in body position. The control of head motion to stabilize a pigeon's gaze may therefore facilitate extraction of important motion cues, in addition to offering mechanisms for controlling body and wing movements. Strong similarities between the sensory flight control of birds and insects may also inspire novel designs of robust controllers for human-engineered autonomous aerial vehicles.

  11. Control of flexible robots with prismatic joints and hydraulic drives

    International Nuclear Information System (INIS)

    Love, L.J.; Kress, R.L.; Jansen, J.F.

    1997-01-01

    The design and control of long-reach, flexible manipulators has been an active research topic for over 20 years. Most of the research to date has focused on single link, fixed length, single plane of vibration test beds. In addition, actuation has been predominantly based upon electromagnetic motors. Ironically, these elements are rarely found in the existing industrial long-reach systems. One example is the Modified Light Duty Utility Arm (MLDUA) designed and built by Spar Aerospace for Oak Ridge National Laboratory (ORNL). This arm operates in larger, underground waste storage tanks located at ORNL. The size and nature of the tanks require that the robot have a reach of approximately 15 ft and a payload capacity of 250 lb. In order to achieve these criteria, each joint is hydraulically actuated. Furthermore, the robot has a prismatic degree-of-freedom to ease deployment. When fully extended, the robot's first natural frequency is 1.76 Hz. Many of the projected tasks, coupled with the robot's flexibility, present an interesting problem. How will many of the existing flexure control algorithms perform on a hydraulic, long-reach manipulator with prismatic links? To minimize cost and risk of testing these algorithms on the MLDUA, the authors have designed a new test bed that contains many of the same elements. This manuscript described a new hydraulically actuated, long-reach manipulator with a flexible prismatic link at ORNL. Focus is directed toward both modeling and control of hydraulic actuators as well as flexible links that have variable natural frequencies

  12. Robust Control of Industrial Hydraulic Cylinder Drives - with Special Reference to Sliding Mode- & Finite-Time Control

    DEFF Research Database (Denmark)

    Schmidt, Lasse

    In industry, performance requirements regarding machinery, applications etc., are constantly increasing, and with the development of reliable proportional flow control components to reasonable prices, the market is increasingly turning its attention toward controllable fluid power solutions....... For series produced systems such as presses etc., dedicated controls are often developed. However, the great majority of the hydraulic systems developed, are produced in limited numbers for specialized applications, and here stand alone economically feasible digital controllers with ease-of-use interfaces...... are widely used. Such controllers typically provide the possibility to employ traditional linear controls such as PID schemes, and variants of this, with parameters tunable via graphical user interfaces. However, due to the intrinsic nonlinearities of hydraulic systems as well as the often limited knowledge...

  13. Experimental study of the pressure discharge process for the hydraulic control rod drive system stepped cylinder

    International Nuclear Information System (INIS)

    Wang, Jinhua; Bo, Hanliang; Zheng, Wenxiang

    2002-01-01

    The pressure discharge process from the stepped cylinder of the Hydraulic Control Rod Drive System (HCRDS) was studied experimentally in the HCRDS experimental loop for the 200 MW Nuclear Heating Reactor (NHR-200). The results showed that the differential pressure between the outside and the inside of the stepped cylinder increased rapidly to the desired value so that the force induced by the differential pressure which pushes the out tube of stepped cylinder was large enough. Therefore, if the hydraulic control rod were jammed, the pressure could push the hydraulic control rod to overcome the frictional resistance to insert the control rod into the reactor core. The experimental results verified that this design would solve the problem of hydraulic control rod jamming during an accident. (author)

  14. F-15 IFCS Intelligent Flight Control System

    Science.gov (United States)

    Bosworth, John T.

    2008-01-01

    This viewgraph presentation gives a detailed description of the F-15 aircraft, flight tests, aircraft performance and overall advanced neural network based flight control technologies for aerospace systems designs.

  15. Linear Perturbation Adaptive Control of Hydraulically Driven Manipulators

    DEFF Research Database (Denmark)

    Andersen, T.O.; Hansen, M.R.; Conrad, Finn

    2004-01-01

    control.Using the Lyapunov approach, under slowly time-varying assumptions, it is shown that the tracking error and the parameter error remain bounded. This bound is a function of the ideal parameters and a bounded disturbance. The control algorithm decouples and linearizes the manipulator so that each......A method for synthesis of a robust adaptive scheme for a hydraulically driven manipulator, that takes full advantage of any known system dynamics to simplify the adaptive control problem for the unknown portion of the dynamics is presented. The control method is based on adaptive perturbation...

  16. Active control of multi-input hydraulic journal bearing system

    Science.gov (United States)

    Chuang, Jen-Chen; Chen, Chi-Yin; Tu, Jia-Ying

    2016-09-01

    Because of the advantages of high accuracy, high capacity, and low friction, the development of hydrostatic bearing for machine tool receives significant attention in the last decades. The mechanics and mechanical design of hydrostatic journal bearing with capillary restrictors has been discussed in literature. However, pragmatically, the undesired loading effects of cutting force tend to result in resonance and instability of the rotor and damage the shaft during operation. Therefore, multi-input, active flow control using state feedback design is proposed in this paper. To this purpose, the proportional pressure valves are added to the hydraulic system as active control devices, and the linearised models of the bearing and valve are discussed and identified. Simulation and experimental work is conducted to verify the proposed active control and parameter identification techniques. The results show that the unbalance responses of the rotor are reduced by the proposed state feedback controller, which is able to regulate the flow pressure effectively, thus enhancing the stability and accuracy of the hydraulic journal bearing.

  17. Transient flow analysis of the single cylinder for the control rod hydraulic driving system

    International Nuclear Information System (INIS)

    Sun, Xinming; Qin, Benke; Bo, Hanliang

    2017-01-01

    Highlights: • The control rod hydraulic driving system(CRHDS) is a new type of built-in control rod drive technology. The hydraulic cylinder is the main component of the CRHDS. • Transient flow phenomenon in the CRHDS is studied by experiments under different working conditions. • The working mechanism of the hydraulic cylinder step motion and the key characteristic parameters are analyzed based on the experimental results. - Abstract: The control rod hydraulic driving system (CRHDS) is a new type of built-in control rod drive technology. In the CRHDS the pulse flow from the pump into the hydraulic cylinder of the control rod hydraulic drive mechanism (CRHDM) is regulated by the integrated valve to perform the step motion of the reactor control rod. Transient flow occurs in the CRHDS during control rod step motion process which is studied by experiments. The time-history curves of flow rate, pressure and inner cylinder displacement were analyzed, and the results show that the water hammer pressure peak during the step-up motion is high, while there are no obvious pressure fluctuations in the corresponding step-down motion. In the step-up process, the pressure fluctuation amplitude increases with the increase of CRHDS driving pressure. The step-up time and the pressure increasing time before step-up decreases with the driving pressure. The step-up pressure increases with the driving pressure. In the step-down process, the step-down time, the step-down pressure and the pressure decreasing time before step-down do not change with the increase of the driving pressure. The experimental results lay the base for the working principle and vibration reduction analysis of the CRHDS and it’s also helpful for improvement of the working performance of the key facilities and instruments of the CRHDS loop.

  18. Design and control of a point absorber wave energy converter with an open loop hydraulic transmission

    International Nuclear Information System (INIS)

    Fan, YaJun; Mu, AnLe; Ma, Tao

    2016-01-01

    Highlights: • Point absorber wave energy converter is presented. • Piston pump module captures and converts wave energy. • Hydraulic accumulator stores/releases the surplus energy. • Fuzzy controller adjusts the displacement of hydraulic motor. • Generator outputs meet the electricity demand precisely. - Abstract: In this paper, a point absorber wave energy converter combined with offshore wind turbine is proposed. In the system, the wave energy is captured and converted into hydraulic energy by a piston pump module, which is combined with a wind turbine floating platform, and then the hydraulic energy is converted into electricity energy by a variable displacement hydraulic motor and induction generator. In order to smooth and stabilize the captured wave energy, a hydraulic accumulator is applied to store and release the excess energy. In order to meet the demand power a fuzzy controller is designed to adjust the displacement of hydraulic motor and controlled the output power. Simulation under irregular wave condition has been carried out to verify the validity of the mathematical model and the effectiveness of the controller strategy. The results show that the wave energy converter system could deliver the required electricity power precisely as the motor output torque is controlled. The accumulator could damp out all the fluctuations in output power, so the wave energy would become a dispatchable power source.

  19. Wind power plants. Hydraulic transmission with control systems for unrestricted number of revolutions

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, R

    1976-09-01

    Basic ideas are presented for the design of a hydraulic transmission with its control system adapted to an electric generator operated by a wind turbine with unrestricted revolutions. The settlement of the principle is shown by means of commercially available parts. The relations of the installed effect, its cost and the length of operational life are discussed. The control system is directly integrated to the hydraulic circuits.

  20. A new generation drilling rig: hydraulically powered and computer controlled

    Energy Technology Data Exchange (ETDEWEB)

    Laurent, M.; Angman, P.; Oveson, D. [Tesco Corp., Calgary, AB, (Canada)

    1999-11-01

    Development, testing and operation of a new generation of hydraulically powered and computer controlled drilling rig that incorporates a number of features that enhance functionality and productivity, is described. The rig features modular construction, a large heated common drilling machinery room, permanently-mounted draw works which, along with the permanently installed top drive, significantly reduces rig-up/rig-down time. Also featured are closed and open hydraulic systems and a unique hydraulic distribution manifold. All functions are controlled through a programmable logic controller (PLC), providing almost unlimited interlocks and calculations to increase rig safety and efficiency. Simplified diagnostic routines, remote monitoring and troubleshooting are also part of the system. To date, two rigs are in operation. Performance of both rigs has been rated as `very good`. Little or no operational problems have been experienced; downtime has averaged 0.61 per cent since August 1998 when the the first of the two rigs went into operation. The most important future application for this rig is for use with the casing drilling process which eliminates the need for drill pipe and tripping. It also reduces the drilling time lost due to unscheduled events such as reaming, fishing and taking kicks while tripping. 1 tab., 6 figs.

  1. Ares I Flight Control System Overview

    Science.gov (United States)

    Hall, Charles; Lee, Chong; Jackson, Mark; Whorton, Mark; West, mark; Brandon, Jay; Hall, Rob A.; Jang, Jimmy; Bedrossian, Naz; Compton, Jimmy; hide

    2008-01-01

    This paper describes the control challenges posed by the Ares I vehicle, the flight control system design and performance analyses used to test and verify the design. The major challenges in developing the control system are structural dynamics, dynamic effects from the powerful first stage booster, aerodynamics, first stage separation and large uncertainties in the dynamic models for all these. Classical control techniques were employed using innovative methods for structural mode filter design and an anti-drift feature to compensate for translational and rotational disturbances. This design was coded into an integrated vehicle flight simulation and tested by Monte Carlo methods. The product of this effort is a linear, robust controller design that is easy to implement, verify and test.

  2. Experimental Study of Hydraulic Control Rod Drive Mechanism for Passive IN-core Cooling System of Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Guk; Kim, Kyung Mo; Jeong, Yeong Shin; Bang, In Cheol [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    CAREM 25 (27 MWe safety systems using hydraulic control rod drives (CRD) studied critical issues that were rod drops with interrupted flow [3]. Hydraulic control rod drive suggested fast shutdown condition using a large gap between piston and cylinder in order to fast drop of neutron absorbing rods. A Passive IN-core Cooling system (PINCs) was suggested for safety enhancement of pressurized water reactors (PWR), small modular reactor (SMR), sodium fast reactor (SFR) in UNIST. PINCs consist of hydraulic control rod drive mechanism (Hydraulic CRDM) and hybrid control rod assembly with heat pipe combined with control rod. The schematic diagram of the hydraulic CRDM for PINCs is shown in Fig. 1. The experimental results show the steady state and transient behavior of the upper cylinder at a low pressure and low temperature. The influence of the working fluid temperature and cylinder mass are investigated. Finally, the heat removal between evaporator section and condenser section is compared with or without the hybrid control rod. Heat removal test of the hybrid heat pipe with hydraulic CRDM system showed the heat transfer coefficient of the bundle hybrid control rod and its effect on evaporator pool. The preliminary test both hydraulic CRDM and heat removal system was conducted, which showed the possibility of the in-core hydraulic drive system for application of PINCs.

  3. Control-oriented reduced order modeling of dipteran flapping flight

    Science.gov (United States)

    Faruque, Imraan

    Flying insects achieve flight stabilization and control in a manner that requires only small, specialized neural structures to perform the essential components of sensing and feedback, achieving unparalleled levels of robust aerobatic flight on limited computational resources. An engineering mechanism to replicate these control strategies could provide a dramatic increase in the mobility of small scale aerial robotics, but a formal investigation has not yet yielded tools that both quantitatively and intuitively explain flapping wing flight as an "input-output" relationship. This work uses experimental and simulated measurements of insect flight to create reduced order flight dynamics models. The framework presented here creates models that are relevant for the study of control properties. The work begins with automated measurement of insect wing motions in free flight, which are then used to calculate flight forces via an empirically-derived aerodynamics model. When paired with rigid body dynamics and experimentally measured state feedback, both the bare airframe and closed loop systems may be analyzed using frequency domain system identification. Flight dynamics models describing maneuvering about hover and cruise conditions are presented for example fruit flies (Drosophila melanogaster) and blowflies (Calliphorids). The results show that biologically measured feedback paths are appropriate for flight stabilization and sexual dimorphism is only a minor factor in flight dynamics. A method of ranking kinematic control inputs to maximize maneuverability is also presented, showing that the volume of reachable configurations in state space can be dramatically increased due to appropriate choice of kinematic inputs.

  4. Contamination Control and Monitoring of Tap Water as Fluid in Industrial Tap Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn; Adelstorp, Anders

    1998-01-01

    Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems.......Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems....

  5. Formation Flight Control System for In-Flight Sweet Spot Estimation

    NARCIS (Netherlands)

    Brodecki, M.; Subbarao, K.; Chu, Q.P.

    2013-01-01

    A formation flight control system has been designed that addresses the unique environment encountered by aircraft flying in formation and in the upwash of the leading aircraft. In order to test the control system a simulation environment has been created that adequately represents the aerodynamic

  6. Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

    The paper presents research results using IT-Tools for CAD and dynamic modelling, simulation, analysis, and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. Matlab/Simulink and CATIA are used as IT-Tools. The contributions include results from on......-going research projects on fluid power and mechatronics based on tap water hydraulic servovalves and linear servo actuators and rotary vane actuators for motion control and power transmission. Development and design a novel water hydraulic rotary vane actuator for robot manipulators. Proposed mathematical...... modelling, control and simulation of a water hydraulic rotary vane actuator applied to power and control a two-links manipulator and evaluate performance. The results include engineering design and test of the proposed simulation models compared with IHA Tampere University’s presentation of research...

  7. Development and Flight Testing of a Neural Network Based Flight Control System on the NF-15B Aircraft

    Science.gov (United States)

    Bomben, Craig R.; Smolka, James W.; Bosworth, John T.; Silliams-Hayes, Peggy S.; Burken, John J.; Larson, Richard R.; Buschbacher, Mark J.; Maliska, Heather A.

    2006-01-01

    The Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft response information to dynamically alter flight control gains. In 2006, the neural network was engaged and allowed to learn in real time to dynamically alter the aircraft handling qualities characteristics in the presence of actual aerodynamic failure conditions injected into the aircraft through the flight control system. The use of neural network and similar adaptive technologies in the design of highly fault and damage tolerant flight control systems shows promise in making future aircraft far more survivable than current technology allows. This paper will present the results of the IFCS flight test program conducted at the NASA Dryden Flight Research Center in 2006, with emphasis on challenges encountered and lessons learned.

  8. Internal Leakage Fault Detection and Tolerant Control of Single-Rod Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    Jianyong Yao

    2014-01-01

    Full Text Available The integration of internal leakage fault detection and tolerant control for single-rod hydraulic actuators is present in this paper. Fault detection is a potential technique to provide efficient condition monitoring and/or preventive maintenance, and fault tolerant control is a critical method to improve the safety and reliability of hydraulic servo systems. Based on quadratic Lyapunov functions, a performance-oriented fault detection method is proposed, which has a simple structure and is prone to implement in practice. The main feature is that, when a prescribed performance index is satisfied (even a slight fault has occurred, there is no fault alarmed; otherwise (i.e., a severe fault has occurred, the fault is detected and then a fault tolerant controller is activated. The proposed tolerant controller, which is based on the parameter adaptive methodology, is also prone to realize, and the learning mechanism is simple since only the internal leakage is considered in parameter adaptation and thus the persistent exciting (PE condition is easily satisfied. After the activation of the fault tolerant controller, the control performance is gradually recovered. Simulation results on a hydraulic servo system with both abrupt and incipient internal leakage fault demonstrate the effectiveness of the proposed fault detection and tolerant control method.

  9. F-14 in banked flight

    Science.gov (United States)

    1979-01-01

    NASA 991, an F-14 Navy Tomcat designated the F-14 (1X), is seen here in banked flight over the desert on a research flight at NASA's Dryden Flight Research Center, Edwards, California. The F-14 was used at Dryden between 1979 and 1985 in extensive high-angle-of-attack and spin-control-and-recovery tests. The NASA/Navy program, which included 212 total flights, acheived considerable improvement in the F-14 high-angle-of-attack flying qualities, improved departure and spin resistance, and contributed to substantial improvements in reducing 'wing rock,' (i.e., tilting from one side to another), at high angles of attack. The Navy had been experiencing inadvertant spin entries caused by the F-14's aileron rudder interconnect. The NASA/Navy/Grumman team developed and tested 4 different configurations of the aileron rudder interconnect to address the spin problem. These problems prompted the Navy to ask the manufacturer, Grumman, and NASA to investigate the issue. NASA 991 had numerous special additions for high-angle-of-attack and spin-recovery research. These included a battery-powered auxiliary power unit, a flight test nose boom, and a special spin recovery system, consisting of forward mounted, hydraulically actuated canards and an emergency spin chute. NASA's F-14 was first flown by NASA research pilots, but was later flown by Grumman, and by Navy test pilots from Patuxent River Naval Air Station (NAS). The Navy test flights with the spin research vehicle constituted the first program that incorporated air combat maneuvering in its test flights at Dryden. The Navy brought F-14s from Point Mugu and Miramar NAS in San Diego to test the new spin control laws in combat situations. Although the new control laws proved valuable, the Navy did not incorporate them into production F-14s until the F-14D, nearly 15 years later.

  10. Fluid Temperature of Aero Hydraulic Systems

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2016-01-01

    Full Text Available In modern supersonic aircrafts due to aerodynamic skin heating a temperature of hydraulics environment significantly exceeds that of permissible for fluids used. The same problem exists for subsonic passenger aircrafts, especially for Airbuses, which have hydraulics of high power where convective heat transfer with the environment is insufficient and there is no required temperature control of fluid. The most significant in terms of heat flow is the flow caused by the loss of power to the pump and when designing the hydraulic system (HS it is necessary to pay very serious attention to it. To use a constant capacity pump is absolutely unacceptable, since HS efficiency in this case is extremely low, and the most appropriate are variable-capacity pumps, cut-off pumps, dual-mode pumps. The HS fluid cooling system should provide high reliability, lightweight, simple design, and a specified heat transfer in all flight modes.A system cooling the fluid by the fuel of feeding lines of the aircraft engines is the most effective, and it is widely used in supersonic aircrafts, where power of cooling system is essential. Subsonic aircrafts widely use convective heat exchangers. In thermal design of the aircraft hydraulics, the focus is generally given to the maximum and minimum temperatures of the HS fluid, the choice of the type of heat exchanger (convective or flow-through, the place of its installation. In calculating the operating temperature of a hydraulic system and its cooling systems it is necessary to determine an increase of the working fluid temperature when throttling it. There are three possible formulas to calculate the fluid temperature in throttling, with the error of a calculated temperature drop from 30% to 4%.The article considers the HS stationary and noon-stationary operating conditions and their calculation, defines temperatures of fluid and methods to control its specified temperature. It also discusses various heat exchanger schemes

  11. Modeling, Optimization & Control of Hydraulic Networks

    DEFF Research Database (Denmark)

    Tahavori, Maryamsadat

    2014-01-01

    . The nonlinear network model is derived based on the circuit theory. A suitable projection is used to reduce the state vector and to express the model in standard state-space form. Then, the controllability of nonlinear nonaffine hydraulic networks is studied. The Lie algebra-based controllability matrix is used......Water supply systems consist of a number of pumping stations, which deliver water to the customers via pipeline networks and elevated reservoirs. A huge amount of drinking water is lost before it reaches to end-users due to the leakage in pipe networks. A cost effective solution to reduce leakage...... in water network is pressure management. By reducing the pressure in the water network, the leakage can be reduced significantly. Also it reduces the amount of energy consumption in water networks. The primary purpose of this work is to develop control algorithms for pressure control in water supply...

  12. Lessons Learned and Flight Results from the F15 Intelligent Flight Control System Project

    Science.gov (United States)

    Bosworth, John

    2006-01-01

    A viewgraph presentation on the lessons learned and flight results from the F15 Intelligent Flight Control System (IFCS) project is shown. The topics include: 1) F-15 IFCS Project Goals; 2) Motivation; 3) IFCS Approach; 4) NASA F-15 #837 Aircraft Description; 5) Flight Envelope; 6) Limited Authority System; 7) NN Floating Limiter; 8) Flight Experiment; 9) Adaptation Goals; 10) Handling Qualities Performance Metric; 11) Project Phases; 12) Indirect Adaptive Control Architecture; 13) Indirect Adaptive Experience and Lessons Learned; 14) Gen II Direct Adaptive Control Architecture; 15) Current Status; 16) Effect of Canard Multiplier; 17) Simulated Canard Failure Stab Open Loop; 18) Canard Multiplier Effect Closed Loop Freq. Resp.; 19) Simulated Canard Failure Stab Open Loop with Adaptation; 20) Canard Multiplier Effect Closed Loop with Adaptation; 21) Gen 2 NN Wts from Simulation; 22) Direct Adaptive Experience and Lessons Learned; and 23) Conclusions

  13. Preliminary flight test results of a fly-by-throttle emergency flight control system on an F-15 airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. G.; Wells, Edward A.

    1993-01-01

    A multi-engine aircraft, with some or all of the flight control system inoperative, may use engine thrust for control. NASA Dryden has conducted a study of the capability and techniques for this emergency flight control method for the F-15 airplane. With an augmented control system, engine thrust, along with appropriate feedback parameters, is used to control flightpath and bank angle. Extensive simulation studies have been followed by flight tests. This paper discusses the principles of throttles-only control, the F-15 airplane, the augmented system, and the flight results including landing approaches with throttles-only control to within 10 ft of the ground.

  14. Use of feedback control to address flight safety issues

    Science.gov (United States)

    Ganguli, Subhabrata

    This thesis addresses three control problems related to flight safety. The first problem relates to the scope of improvement in performance of conventional flight control laws. In particular, aircraft longitudinal axis control based on the Total Energy Control System (TECS) is studied. The research draws attention to a potentially sluggish and undesirable aircraft response when the engine dynamics is slow (typically the case). The proposed design method uses a theoretically well-developed modern design method based on Hinfinity optimization to improve the aircraft dynamic behavior in spite of slow engine characteristics. At the same time, the proposed design method achieves other desirable performance goals such as insensitivity to sensor noise and wind gust rejection: all addressed in one unified framework. The second problem is based on a system level analysis of control structure hierarchy for aircraft flight control. The objective of the analysis problem is to translate outer-loop stability and performance specifications into a comprehensive inner-loop metric. The prime motivation is to make the flight control design process more systematic and the system-integration reliable and independent of design methodology. The analysis problem is posed within the robust control analysis framework. Structured singular value techniques and free controller parameterization ideas are used to impose a hierarchical structure for flight control architecture. The third problem involves development and demonstration of a new reconfiguration strategy in the flight control architecture that has the potential of improving flight safety while keeping cost and complexity low. This research proposes a fault tolerant feature based on active robust reconfiguration. The fault tolerant control problem is formulated in the Linear Parameter Varying (LPV) design framework. A prime advantage of this approach is that the synthesis results in a single nonlinear controller (as opposed to a bank

  15. Nocturnal insects use optic flow for flight control

    OpenAIRE

    Baird, Emily; Kreiss, Eva; Wcislo, William; Warrant, Eric; Dacke, Marie

    2011-01-01

    To avoid collisions when navigating through cluttered environments, flying insects must control their flight so that their sensory systems have time to detect obstacles and avoid them. To do this, day-active insects rely primarily on the pattern of apparent motion generated on the retina during flight (optic flow). However, many flying insects are active at night, when obtaining reliable visual information for flight control presents much more of a challenge. To assess whether nocturnal flyin...

  16. A device for the hydraulic control of nuclear reactor control rods

    International Nuclear Information System (INIS)

    Frisch, Erling; Frisch, D.R.; Andrews, H.N.

    1974-01-01

    A device for driving and locking the control rods of a nuclear reactor. This device comprises a hydraulic driving piston mounted in a cylinder provided with a construction for absorbing shocks. The piston is provided, at is extremity, with a locking device adapted to engage a stationary lock, it being possible to control the latter for freeing said piston locking device; with such an arrangement, the control rod is normally maintained in position, and it can be freed only by a positive signal. Moreover, the control rod movements are slowed down, so as to prevent the gripping device from being damaged. This device can be used in the nuclear industry [fr

  17. Design and Testing of Flight Control Laws on the RASCAL Research Helicopter

    Science.gov (United States)

    Frost, Chad R.; Hindson, William S.; Moralez. Ernesto, III; Tucker, George E.; Dryfoos, James B.

    2001-01-01

    Two unique sets of flight control laws were designed, tested and flown on the Army/NASA Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH-60A Black Hawk helicopter. The first set of control laws used a simple rate feedback scheme, intended to facilitate the first flight and subsequent flight qualification of the RASCAL research flight control system. The second set of control laws comprised a more sophisticated model-following architecture. Both sets of flight control laws were developed and tested extensively using desktop-to-flight modeling, analysis, and simulation tools. Flight test data matched the model predicted responses well, providing both evidence and confidence that future flight control development for RASCAL will be efficient and accurate.

  18. Simulation to Flight Test for a UAV Controls Testbed

    Science.gov (United States)

    Motter, Mark A.; Logan, Michael J.; French, Michael L.; Guerreiro, Nelson M.

    2006-01-01

    The NASA Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron segments, supports the implementation of C-coded experimental controllers, and is capable of fully autonomous flight from takeoff roll to landing, including flight test maneuvers. The test vehicle is basically a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate (AATD) at Fort Eustis, Virginia and NASA Langley Research Center. Several vehicles have been constructed and collectively have flown over 600 successful test flights, including a fully autonomous demonstration at the Association of Unmanned Vehicle Systems International (AUVSI) UAV Demo 2005. Simulations based on wind tunnel data are being used to further develop advanced controllers for implementation and flight test.

  19. Integrating Space Flight Resource Management Skills into Technical Lessons for International Space Station Flight Controller Training

    Science.gov (United States)

    Baldwin, Evelyn

    2008-01-01

    The Johnson Space Center s (JSC) International Space Station (ISS) Space Flight Resource Management (SFRM) training program is designed to teach the team skills required to be an effective flight controller. It was adapted from the SFRM training given to Shuttle flight controllers to fit the needs of a "24 hours a day/365 days a year" flight controller. More recently, the length reduction of technical training flows for ISS flight controllers impacted the number of opportunities for fully integrated team scenario based training, where most SFRM training occurred. Thus, the ISS SFRM training program is evolving yet again, using a new approach of teaching and evaluating SFRM alongside of technical materials. Because there are very few models in other industries that have successfully tied team and technical skills together, challenges are arising. Despite this, the Mission Operations Directorate of NASA s JSC is committed to implementing this integrated training approach because of the anticipated benefits.

  20. Flight controller design of unmanned airplane for radiation monitoring system via structured robust controller design using multiple model approach. Radiation monitoring flight in Namie-machi in Fukushima prefecture

    International Nuclear Information System (INIS)

    Sato, Masayuki; Muraoka, Koji; Hozumi, Koki; Sanada, Yukihisa; Yamada, Tsutomu; Torii, Tatsuo

    2015-01-01

    Due to the tragic accident of radioactive contaminant spread from Fukushima Dai-ichi nuclear power plant, the necessity of unmanned systems for radiation monitoring has been increasing. This paper concerns the flight controller design of an unmanned airplane which has been developed for radiation monitoring around the power plant. The flight controller consists of conventional control elements, i.e. Stability/Control Augmentation System (S/CAS) with PI controllers and guidance loops with PID controllers. The gains in these controllers are designed by minimizing appropriately defined cost functions for several possible models and disturbances to produce structured robust flight controllers. (This method is called as 'multiple model approach'.) Control performance of our flight controller was evaluated through flight tests and a primitive flight of radiation monitoring in Namie-machi in Fukushima prefecture was conducted in Jan. 2014. Flight results are included in this paper. (author)

  1. Nocturnal insects use optic flow for flight control.

    Science.gov (United States)

    Baird, Emily; Kreiss, Eva; Wcislo, William; Warrant, Eric; Dacke, Marie

    2011-08-23

    To avoid collisions when navigating through cluttered environments, flying insects must control their flight so that their sensory systems have time to detect obstacles and avoid them. To do this, day-active insects rely primarily on the pattern of apparent motion generated on the retina during flight (optic flow). However, many flying insects are active at night, when obtaining reliable visual information for flight control presents much more of a challenge. To assess whether nocturnal flying insects also rely on optic flow cues to control flight in dim light, we recorded flights of the nocturnal neotropical sweat bee, Megalopta genalis, flying along an experimental tunnel when: (i) the visual texture on each wall generated strong horizontal (front-to-back) optic flow cues, (ii) the texture on only one wall generated these cues, and (iii) horizontal optic flow cues were removed from both walls. We find that Megalopta increase their groundspeed when horizontal motion cues in the tunnel are reduced (conditions (ii) and (iii)). However, differences in the amount of horizontal optic flow on each wall of the tunnel (condition (ii)) do not affect the centred position of the bee within the flight tunnel. To better understand the behavioural response of Megalopta, we repeated the experiments on day-active bumble-bees (Bombus terrestris). Overall, our findings demonstrate that despite the limitations imposed by dim light, Megalopta-like their day-active relatives-rely heavily on vision to control flight, but that they use visual cues in a different manner from diurnal insects. This journal is © 2011 The Royal Society

  2. The kinematics of the rigid feedback linkage, the impedance of the hydraulic servomechanism and the flutter occurrence

    Directory of Open Access Journals (Sweden)

    Ioan URSU

    2012-09-01

    Full Text Available The paper brought to light a previous result of the author, used in the design of hydraulicservos actuating flight controls of the airplanes IAR 93 and IAR 99. The results highlights theimportance of the the kinematics of the rigid feedback linkage of the hydraulic servo in anaeroservoelastic frame.

  3. Flight Test Results for the F-16XL With a Digital Flight Control System

    Science.gov (United States)

    Stachowiak, Susan J.; Bosworth, John T.

    2004-01-01

    In the early 1980s, two F-16 airplanes were modified to extend the fuselage length and incorporate a large area delta wing planform. These two airplanes, designated the F-16XL, were designed by the General Dynamics Corporation (now Lockheed Martin Tactical Aircraft Systems) (Fort Worth, Texas) and were prototypes for a derivative fighter evaluation program conducted by the United States Air Force. Although the concept was never put into production, the F-16XL prototypes provided a unique planform for testing concepts in support of future high-speed supersonic transport aircraft. To extend the capabilities of this testbed vehicle the F-16XL ship 1 aircraft was upgraded with a digital flight control system. The added flexibility of a digital flight control system increases the versatility of this airplane as a testbed for aerodynamic research and investigation of advanced technologies. This report presents the handling qualities flight test results covering the envelope expansion of the F-16XL with the digital flight control system.

  4. Optimal Design and Hybrid Control for the Electro-Hydraulic Dual-Shaking Table System

    Directory of Open Access Journals (Sweden)

    Lianpeng Zhang

    2016-08-01

    Full Text Available This paper is to develop an optimal electro-hydraulic dual-shaking table system with high waveform replication precision. The parameters of hydraulic cylinders, servo valves, hydraulic supply power and gravity balance system are designed and optimized in detail. To improve synchronization and tracking control precision, a hybrid control strategy is proposed. The cross-coupled control using a novel based on sliding mode control based on adaptive reaching law (ASMC, which can adaptively tune the parameters of sliding mode control (SMC, is proposed to reduce the synchronization error. To improve the tracking performance, the observer-based inverse control scheme combining the feed-forward inverse model controller and disturbance observer is proposed. The system model is identified applying the recursive least squares (RLS algorithm and then the feed-forward inverse controller is designed based on zero phase error tracking controller (ZPETC technique. To compensate disturbance and model errors, disturbance observer is used cooperating with the designed inverse controller. The combination of the novel ASMC cross-coupled controller and proposed observer-based inverse controller can improve the control precision noticeably. The dual-shaking table experiment system is built and various experiments are performed. The experimental results indicate that the developed system with the proposed hybrid control strategy is feasible and efficient and can reduce the tracking errors to 25% and synchronization error to 16% compared with traditional control schemes.

  5. Development and Flight Evaluation of an Emergency Digital Flight Control System Using Only Engine Thrust on an F-15 Airplane

    Science.gov (United States)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. Gordon; Webb, Lannie Dean

    1996-01-01

    A propulsion-controlled aircraft (PCA) system for emergency flight control of aircraft with no flight controls was developed and flight tested on an F-15 aircraft at the NASA Dryden Flight Research Center. The airplane has been flown in a throttles-only manual mode and with an augmented system called PCA in which pilot thumbwheel commands and aircraft feedback parameters were used to drive the throttles. Results from a 36-flight evaluation showed that the PCA system can be used to safety land an airplane that has suffered a major flight control system failure. The PCA system was used to recover from a severe upset condition, descend, and land. Guest pilots have also evaluated the PCA system. This paper describes the principles of throttles-only flight control; a history of loss-of-control accidents; a description of the F-15 aircraft; the PCA system operation, simulation, and flight testing; and the pilot comments.

  6. Hydraulically driven control rod concept for integral reactors: fluid dynamic simulation and preliminary test

    International Nuclear Information System (INIS)

    Ricotti, M.E.; Cammi, A.; Lombardi, C.; Passoni, M.; Rizzo, C.; Carelli, M.; Colombo, E.

    2003-01-01

    The paper deals with the preliminary study of the Hydraulically Driven Control Rod concept, tailored for PWR control rods (spider type) with hydraulic drive mechanism completely immersed in the primary water. A specific solution suitable for advanced versions of the IRIS integral reactor is under investigation. The configuration of the Hydraulic Control Rod device, made up by an external movable piston and an internal fixed cylinder, is described. After a brief description of the whole control system, particular attention is devoted to the Control Rod characterization via Computational Fluid Dynamics (CFD) analysis. The investigation of the system behavior, including dynamic equilibrium and stability properties, has been carried out. Finally, preliminary tests were performed in a low pressure, low temperature, reduced length experimental facility. The results are compared with the dynamic control model and CFD simulation model, showing good agreement between simulations and experimental data. During these preliminary tests, the control system performs correctly, allowing stable dynamic equilibrium positions for the Control Rod and stable behavior during withdrawal and insertion steps. (author)

  7. A Study on Control Strategy of Regenerative Braking in the Hydraulic Hybrid Vehicle Based on ECE Regulations

    Directory of Open Access Journals (Sweden)

    Tao Liu

    2013-01-01

    Full Text Available This paper establishes a mathematic model of composite braking in the hydraulic hybrid vehicle and analyzes the constraint condition of parallel regenerative braking control algorithm. Based on regenerative braking system character and ECE (Economic Commission of Europe regulations, it introduces the control strategy of regenerative braking in parallel hydraulic hybrid vehicle (PHHV. Finally, the paper establishes the backward simulation model of the hydraulic hybrid vehicle in Matlab/simulink and makes a simulation analysis of the control strategy of regenerative braking. The results show that this strategy can equip the hydraulic hybrid vehicle with strong brake energy recovery power in typical urban drive state.

  8. Real-time tracking control of electro-hydraulic force servo systems using offline feedback control and adaptive control.

    Science.gov (United States)

    Shen, Gang; Zhu, Zhencai; Zhao, Jinsong; Zhu, Weidong; Tang, Yu; Li, Xiang

    2017-03-01

    This paper focuses on an application of an electro-hydraulic force tracking controller combined with an offline designed feedback controller (ODFC) and an online adaptive compensator in order to improve force tracking performance of an electro-hydraulic force servo system (EHFS). A proportional-integral controller has been employed and a parameter-based force closed-loop transfer function of the EHFS is identified by a continuous system identification algorithm. By taking the identified system model as a nominal plant model, an H ∞ offline design method is employed to establish an optimized feedback controller with consideration of the performance, control efforts, and robustness of the EHFS. In order to overcome the disadvantage of the offline designed controller and cope with the varying dynamics of the EHFS, an online adaptive compensator with a normalized least-mean-square algorithm is cascaded to the force closed-loop system of the EHFS compensated by the ODFC. Some comparative experiments are carried out on a real-time EHFS using an xPC rapid prototype technology, and the proposed controller yields a better force tracking performance improvement. Copyright © 2016. Published by Elsevier Ltd.

  9. A compound control strategy combining velocity compensation with ADRC of electro-hydraulic position servo control system.

    Science.gov (United States)

    Gao, Bingwei; Shao, Junpeng; Yang, Xiaodong

    2014-11-01

    In order to enhance the anti-jamming ability of electro-hydraulic position servo control system at the same time improve the control precision of the system, a compound control strategy that combines velocity compensation with Active Disturbance Rejection Controller (ADRC) is proposed, and the working principle of the compound control strategy is given. ADRC controller is designed, and the extended state observer is used for observing internal parameters uncertainties and external disturbances, so that the disturbances of the system are suppressed effectively. Velocity compensation controller is designed and the compensation model is derived to further improve the positioning accuracy of the system and to achieve the velocity compensation without disturbance. The compound control strategy is verified by the simulation and experiment respectively, and the simulation and experimental results show that the electro-hydraulic position servo control system with ADRC controller can effectively inhibit the external disturbances, the precise positioning control is realized after introducing the velocity compensation controller, and verify that the compound control strategy is effective. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Seismic analysis of hydraulic control rod driving system

    International Nuclear Information System (INIS)

    Zheng, Yanhua; Bo, Hanliang; Dong, Duo

    2002-01-01

    A simplified mathematical model was developed for the Hydraulic Control Rod Driving System (HCRDS) of a 200 MW nuclear heating reactor, which incorporated the design of its chamfer-hole step cylinder, to analyze its seismic response characteristics. The control rod motion was analyzed for different sine-wave vibration loadings on platform vibrator. The vibration frequency domain and the minimum acceleration amplitude of the control rod needed to cause the control rod to step to its next setting were compared with the design acceleration amplitude spectrum. The system design was found to be safety within the calculated limits. The safety margin increased with increasing frequency. (author)

  11. Model predictive control-based dynamic coordinate strategy for hydraulic hub-motor auxiliary system of a heavy commercial vehicle

    Science.gov (United States)

    Zeng, Xiaohua; Li, Guanghan; Yin, Guodong; Song, Dafeng; Li, Sheng; Yang, Nannan

    2018-02-01

    Equipping a hydraulic hub-motor auxiliary system (HHMAS), which mainly consists of a hydraulic variable pump, a hydraulic hub-motor, a hydraulic valve block and hydraulic accumulators, with part-time all-wheel-drive functions improves the power performance and fuel economy of heavy commercial vehicles. The coordinated control problem that occurs when HHMAS operates in the auxiliary drive mode is addressed in this paper; the solution to this problem is the key to the maximization of HHMAS. To achieve a reasonable distribution of the engine power between mechanical and hydraulic paths, a nonlinear control scheme based on model predictive control (MPC) is investigated. First, a nonlinear model of HHMAS with vehicle dynamics and tire slip characteristics is built, and a controller-design-oriented model is simplified. Then, a steady-state feedforward + dynamic MPC feedback controller (FMPC) is designed to calculate the control input sequence of engine torque and hydraulic variable pump displacement. Finally, the controller is tested in the MATLAB/Simulink and AMESim co-simulation platform and the hardware-in-the-loop experiment platform, and its performance is compared with that of the existing proportional-integral-derivative controller and the feedforward controller under the same conditions. Simulation results show that the designed FMPC has the best performance, and control performance can be guaranteed in a real-time environment. Compared with the tracking control error of the feedforward controller, that of the designed FMPC is decreased by 85% and the traction efficiency performance is improved by 23% under a low-friction-surface condition. Moreover, under common road conditions for heavy commercial vehicles, the traction force can increase up to 13.4-15.6%.

  12. Research on the Robustness of the Constant Speed Control of Hydraulic Energy Storage Generation

    Directory of Open Access Journals (Sweden)

    Zengguang Liu

    2018-05-01

    Full Text Available Energy storage plays a major role in solving the fluctuation and intermittence problem of wind and the effective use of wind power. The application of the hydraulic accumulator is the most efficient and convenient way to store wind energy in hydraulic wind turbines. A hydraulic energy storage generation system (HESGS can transform hydraulic energy stored in the hydraulic accumulator into stable and constant electrical energy by controlling the variable motor, regardless of wind changes. The aim of the present study is to design a constant speed control method for the variable motor in the HESGS and investigate the influence of the controller’s main parameters on the resistance of the HESGS to external load power disturbances. Mathematical equations of all components in this system are introduced and an entire system simulation model is built. A double closed-loop control method of the variable motor is presented within this paper, which keeps the motor speed constant for the fixed frequency of electrical power generated by the HESGS. Ultimately, a series of simulations with different proportional gains and integral gains under the environment of changeless load power step are conducted. At the same time, comparison analyses of the experiment and simulation under variable load power step are performed. The results verify the correctness and the usability of the simulation model, and also indicate that the proposed control method is robust to the disturbances of changing load power.

  13. Modeling and stability of electro-hydraulic servo of hydraulic excavator

    Science.gov (United States)

    Jia, Wenhua; Yin, Chenbo; Li, Guo; Sun, Menghui

    2017-11-01

    The condition of the hydraulic excavator is complicated and the working environment is bad. The safety and stability of the control system is influenced by the external factors. This paper selects hydraulic excavator electro-hydraulic servo system as the research object. A mathematical model and simulation model using AMESIM of servo system is established. Then the pressure and flow characteristics are analyzed. The design and optimization of electro-hydraulic servo system and its application in engineering machinery is provided.

  14. Design and Analysis of Morpheus Lander Flight Control System

    Science.gov (United States)

    Jang, Jiann-Woei; Yang, Lee; Fritz, Mathew; Nguyen, Louis H.; Johnson, Wyatt R.; Hart, Jeremy J.

    2014-01-01

    The Morpheus Lander is a vertical takeoff and landing test bed vehicle developed to demonstrate the system performance of the Guidance, Navigation and Control (GN&C) system capability for the integrated autonomous landing and hazard avoidance system hardware and software. The Morpheus flight control system design must be robust to various mission profiles. This paper presents a design methodology for employing numerical optimization to develop the Morpheus flight control system. The design objectives include attitude tracking accuracy and robust stability with respect to rigid body dynamics and propellant slosh. Under the assumption that the Morpheus time-varying dynamics and control system can be frozen over a short period of time, the flight controllers are designed to stabilize all selected frozen-time control systems in the presence of parametric uncertainty. Both control gains in the inner attitude control loop and guidance gains in the outer position control loop are designed to maximize the vehicle performance while ensuring robustness. The flight control system designs provided herein have been demonstrated to provide stable control systems in both Draper Ares Stability Analysis Tool (ASAT) and the NASA/JSC Trick-based Morpheus time domain simulation.

  15. A rotorcraft flight/propulsion control integration study

    Science.gov (United States)

    Ruttledge, D. G. C.

    1986-01-01

    An eclectic approach was taken to a study of the integration of digital flight and propulsion controls for helicopters. The basis of the evaluation was the current Gen Hel simulation of the UH-60A Black Hawk helicopter with a model of the GE T700 engine. A list of flight maneuver segments to be used in evaluating the effectiveness of such an integrated control system was composed, based on past experience and an extensive survey of the U.S. Army Air-to-Air Combat Test data. A number of possible features of an integrated system were examined and screened. Those that survived the screening were combined into a design that replaced the T700 fuel control and part of the control system in the UH-60A Gen Hel simulation. This design included portions of an existing pragmatic adaptive fuel control designed by the Chandler-Evans Company and an linear quadratic regulator (LQR) based N(p) governor designed by the GE company, combined with changes in the basic Sikorsky Aircraft designed control system. The integrated system exhibited improved total performance in many areas of the flight envelope.

  16. Development and Evaluation of Fault-Tolerant Flight Control Systems

    Science.gov (United States)

    Song, Yong D.; Gupta, Kajal (Technical Monitor)

    2004-01-01

    The research is concerned with developing a new approach to enhancing fault tolerance of flight control systems. The original motivation for fault-tolerant control comes from the need for safe operation of control elements (e.g. actuators) in the event of hardware failures in high reliability systems. One such example is modem space vehicle subjected to actuator/sensor impairments. A major task in flight control is to revise the control policy to balance impairment detectability and to achieve sufficient robustness. This involves careful selection of types and parameters of the controllers and the impairment detecting filters used. It also involves a decision, upon the identification of some failures, on whether and how a control reconfiguration should take place in order to maintain a certain system performance level. In this project new flight dynamic model under uncertain flight conditions is considered, in which the effects of both ramp and jump faults are reflected. Stabilization algorithms based on neural network and adaptive method are derived. The control algorithms are shown to be effective in dealing with uncertain dynamics due to external disturbances and unpredictable faults. The overall strategy is easy to set up and the computation involved is much less as compared with other strategies. Computer simulation software is developed. A serious of simulation studies have been conducted with varying flight conditions.

  17. Morphing Flight Control Surface for Advanced Flight Performance, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In this SBIR project, a new Morphing Flight Control Surface (MFCS) will be developed. The distinction of the research effort is that the SenAnTech team will employ...

  18. Flight Control of the High Altitude Wind Power System

    NARCIS (Netherlands)

    Podgaets, A.R.; Ockels, W.J.

    2007-01-01

    Closed loop Laddermill flight control problem is considered in this paper. Laddermill is a high altitude kites system for energy production. The kites have been simulated as rigid bodies and the cable as a thin elastic line. Euler angles and cable speed are controls. Flight control is written as a

  19. Design Challenges Encountered in a Propulsion-Controlled Aircraft Flight Test Program

    Science.gov (United States)

    Maine, Trindel; Burken, John; Burcham, Frank; Schaefer, Peter

    1994-01-01

    The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flightpath and bank angle using only commands to the throttles. Although the program was highly successful, this paper highlights some of the challenges associated with using engine thrust as a control effector. These challenges include slow engine response time, poorly modeled nonlinear engine dynamics, unmodeled inlet-airframe interactions, and difficulties with ground effect and gust rejection. Flight and simulation data illustrate these difficulties.

  20. Design of Intelligent Hydraulic Excavator Control System Based on PID Method

    Science.gov (United States)

    Zhang, Jun; Jiao, Shengjie; Liao, Xiaoming; Yin, Penglong; Wang, Yulin; Si, Kuimao; Zhang, Yi; Gu, Hairong

    Most of the domestic designed hydraulic excavators adopt the constant power design method and set 85%~90% of engine power as the hydraulic system adoption power, it causes high energy loss due to mismatching of power between the engine and the pump. While the variation of the rotational speed of engine could sense the power shift of the load, it provides a new method to adjust the power matching between engine and pump through engine speed. Based on negative flux hydraulic system, an intelligent hydraulic excavator control system was designed based on rotational speed sensing method to improve energy efficiency. The control system was consisted of engine control module, pump power adjusted module, engine idle module and system fault diagnosis module. Special PLC with CAN bus was used to acquired the sensors and adjusts the pump absorption power according to load variation. Four energy saving control strategies with constant power method were employed to improve the fuel utilization. Three power modes (H, S and L mode) were designed to meet different working status; Auto idle function was employed to save energy through two work status detected pressure switches, 1300rpm was setting as the idle speed according to the engine consumption fuel curve. Transient overload function was designed for deep digging within short time without spending extra fuel. An increasing PID method was employed to realize power matching between engine and pump, the rotational speed's variation was taken as the PID algorithm's input; the current of proportional valve of variable displacement pump was the PID's output. The result indicated that the auto idle could decrease fuel consumption by 33.33% compared to work in maximum speed of H mode, the PID control method could take full use of maximum engine power at each power mode and keep the engine speed at stable range. Application of rotational speed sensing method provides a reliable method to improve the excavator's energy efficiency and

  1. Hybrid adaptive ascent flight control for a flexible launch vehicle

    Science.gov (United States)

    Lefevre, Brian D.

    For the purpose of maintaining dynamic stability and improving guidance command tracking performance under off-nominal flight conditions, a hybrid adaptive control scheme is selected and modified for use as a launch vehicle flight controller. This architecture merges a model reference adaptive approach, which utilizes both direct and indirect adaptive elements, with a classical dynamic inversion controller. This structure is chosen for a number of reasons: the properties of the reference model can be easily adjusted to tune the desired handling qualities of the spacecraft, the indirect adaptive element (which consists of an online parameter identification algorithm) continually refines the estimates of the evolving characteristic parameters utilized in the dynamic inversion, and the direct adaptive element (which consists of a neural network) augments the linear feedback signal to compensate for any nonlinearities in the vehicle dynamics. The combination of these elements enables the control system to retain the nonlinear capabilities of an adaptive network while relying heavily on the linear portion of the feedback signal to dictate the dynamic response under most operating conditions. To begin the analysis, the ascent dynamics of a launch vehicle with a single 1st stage rocket motor (typical of the Ares 1 spacecraft) are characterized. The dynamics are then linearized with assumptions that are appropriate for a launch vehicle, so that the resulting equations may be inverted by the flight controller in order to compute the control signals necessary to generate the desired response from the vehicle. Next, the development of the hybrid adaptive launch vehicle ascent flight control architecture is discussed in detail. Alterations of the generic hybrid adaptive control architecture include the incorporation of a command conversion operation which transforms guidance input from quaternion form (as provided by NASA) to the body-fixed angular rate commands needed by the

  2. Nonlinear, Adaptive and Fault-tolerant Control for Electro-hydraulic Servo Systems

    DEFF Research Database (Denmark)

    Choux, Martin

    is designed and implemented on the test bed that successfully diagnoses internal or external leakages, friction variations in the actuator or fault related to pressure sensors. The presented algorithm uses the position and pressure measurements to detect and isolate faults, avoiding missed detection and false...... numerous attractive properties, hydraulic systems are always subject to potential leakages in their components, friction variation in their hydraulic actuators and deciency in their sensors. These violations of normal behaviour reduce the system performances and can lead to system failure...... if they are not detected early and handled. Moreover, the task of controlling electro hydraulic systems for high performance operations is challenging due to the highly nonlinear behaviour of such systems and the large amount of uncertainties present in their models. This thesis focuses on nonlinear adaptive fault...

  3. Performance evaluation and design of flight vehicle control systems

    CERN Document Server

    Falangas, Eric T

    2015-01-01

    This book will help students, control engineers and flight dynamics analysts to model and conduct sophisticated and systemic analyses of early flight vehicle designs controlled with multiple types of effectors and to design and evaluate new vehicle concepts in terms of satisfying mission and performance goals. Performance Evaluation and Design of Flight Vehicle Control Systems begins by creating a dynamic model of a generic flight vehicle that includes a range of elements from airplanes and launch vehicles to re-entry vehicles and spacecraft. The models may include dynamic effects dealing with structural flexibility, as well as dynamic coupling between structures and actuators, propellant sloshing, and aeroelasticity, and they are typically used for control analysis and design. The book shows how to efficiently combine different types of effectors together, such as aero-surfaces, TVC, throttling engines and RCS, to operate as a system by developing a mixing logic atrix. Methods of trimming a vehicle controll...

  4. a design to digitalize hydraulic cylinder control of a machine tool

    African Journals Online (AJOL)

    Dr Obe

    1995-09-01

    Sep 1, 1995 ... Department of Mechanical Engineering. FEDERAL UNIVERSITY OF TECHNOLOGY, OWERRI,. P.M.B. 1526, OWERRI. ABSTRACT. Conventionally hydraulic piston - cylinder servos are actuated using analogue controls for machine tool axis drives. In this paper a design of the axis control system of an NC ...

  5. A Study on Control Strategy of Regenerative Braking in the Hydraulic Hybrid Vehicle Based on ECE Regulations

    OpenAIRE

    Liu, Tao; Zheng, Jincheng; Su, Yongmao; Zhao, Jinghui

    2013-01-01

    This paper establishes a mathematic model of composite braking in the hydraulic hybrid vehicle and analyzes the constraint condition of parallel regenerative braking control algorithm. Based on regenerative braking system character and ECE (Economic Commission of Europe) regulations, it introduces the control strategy of regenerative braking in parallel hydraulic hybrid vehicle (PHHV). Finally, the paper establishes the backward simulation model of the hydraulic hybrid vehicle in Matlab/simul...

  6. Automatic Reverse Engineering of Private Flight Control Protocols of UAVs

    Directory of Open Access Journals (Sweden)

    Ran Ji

    2017-01-01

    Full Text Available The increasing use of civil unmanned aerial vehicles (UAVs has the potential to threaten public safety and privacy. Therefore, airspace administrators urgently need an effective method to regulate UAVs. Understanding the meaning and format of UAV flight control commands by automatic protocol reverse-engineering techniques is highly beneficial to UAV regulation. To improve our understanding of the meaning and format of UAV flight control commands, this paper proposes a method to automatically analyze the private flight control protocols of UAVs. First, we classify flight control commands collected from a binary network trace into clusters; then, we analyze the meaning of flight control commands by the accumulated error of each cluster; next, we extract the binary format of commands and infer field semantics in these commands; and finally, we infer the location of the check field in command and the generator polynomial matrix. The proposed approach is validated via experiments on a widely used consumer UAV.

  7. Flight test of the X-29A at high angle of attack: Flight dynamics and controls

    Science.gov (United States)

    Bauer, Jeffrey E.; Clarke, Robert; Burken, John J.

    1995-01-01

    The NASA Dryden Flight Research Center has flight tested two X-29A aircraft at low and high angles of attack. The high-angle-of-attack tests evaluate the feasibility of integrated X-29A technologies. More specific objectives focus on evaluating the high-angle-of-attack flying qualities, defining multiaxis controllability limits, and determining the maximum pitch-pointing capability. A pilot-selectable gain system allows examination of tradeoffs in airplane stability and maneuverability. Basic fighter maneuvers provide qualitative evaluation. Bank angle captures permit qualitative data analysis. This paper discusses the design goals and approach for high-angle-of-attack control laws and provides results from the envelope expansion and handling qualities testing at intermediate angles of attack. Comparisons of the flight test results to the predictions are made where appropriate. The pitch rate command structure of the longitudinal control system is shown to be a valid design for high-angle-of-attack control laws. Flight test results show that wing rock amplitude was overpredicted and aileron and rudder effectiveness were underpredicted. Flight tests show the X-29A airplane to be a good aircraft up to 40 deg angle of attack.

  8. A new linearized equation for servo valve in hydraulic control systems

    International Nuclear Information System (INIS)

    Kim, Tae Hyung; Lee, Ill Yeong

    2002-01-01

    In the procedure of the hydraulic control system analysis, a linearized approximate equation described by the first order term of Taylor's series has been widely used. Such a linearized equation is effective just near the operating point. And, as of now, there are no general standards on how to determine the operating point of a servo valve in the process of applying the linearized equation. So, in this study, a new linearized equation for valve characteristics is proposed as a modified form of the existing linearized equation. And, a method for selecting an optimal operating point is proposed for the new linearized equation. The effectiveness of the new linearized equation is confirmed through numerical simulations and experiments for a model hydraulic control system

  9. Human factors implications of unmanned aircraft accidents : flight-control problems

    Science.gov (United States)

    2006-04-01

    This research focuses on three types of flight control problems associated with unmanned aircraft systems. The : three flight control problems are: 1) external pilot difficulties with inconsistent mapping of the controls to the : movement of the airc...

  10. Software Considerations for Subscale Flight Testing of Experimental Control Laws

    Science.gov (United States)

    Murch, Austin M.; Cox, David E.; Cunningham, Kevin

    2009-01-01

    The NASA AirSTAR system has been designed to address the challenges associated with safe and efficient subscale flight testing of research control laws in adverse flight conditions. In this paper, software elements of this system are described, with an emphasis on components which allow for rapid prototyping and deployment of aircraft control laws. Through model-based design and automatic coding a common code-base is used for desktop analysis, piloted simulation and real-time flight control. The flight control system provides the ability to rapidly integrate and test multiple research control laws and to emulate component or sensor failures. Integrated integrity monitoring systems provide aircraft structural load protection, isolate the system from control algorithm failures, and monitor the health of telemetry streams. Finally, issues associated with software configuration management and code modularity are briefly discussed.

  11. The integrated manual and automatic control of complex flight systems

    Science.gov (United States)

    Schmidt, David K.

    1991-01-01

    Research dealt with the general area of optimal flight control synthesis for manned flight vehicles. The work was generic; no specific vehicle was the focus of study. However, the class of vehicles generally considered were those for which high authority, multivariable control systems might be considered, for the purpose of stabilization and the achievement of optimal handling characteristics. Within this scope, the topics of study included several optimal control synthesis techniques, control-theoretic modeling of the human operator in flight control tasks, and the development of possible handling qualities metrics and/or measures of merit. Basic contributions were made in all these topics, including human operator (pilot) models for multi-loop tasks, optimal output feedback flight control synthesis techniques; experimental validations of the methods developed, and fundamental modeling studies of the air-to-air tracking and flared landing tasks.

  12. Modeling and control of a hydraulically actuated flexible-prismatic link robot

    International Nuclear Information System (INIS)

    Love, L.; Kress, R.; Jansen, J.

    1996-12-01

    Most of the research related to flexible link manipulators to date has focused on single link, fixed length, single plane of vibration test beds. In addition, actuation has been predominantly based upon electromagnetic motors. Ironically, these elements are rarely found in the existing industrial long reach systems. This manuscript describes a new hydraulically actuated, long reach manipulator with a flexible prismatic link at Oak Ridge National Laboratory (ORNL). Focus is directed towards both modeling and control of hydraulic actuators as well as flexible links that have variable natural frequencies

  13. Real-time neural network-based self-tuning control of a nonlinear electro-hydraulic servomotor

    Energy Technology Data Exchange (ETDEWEB)

    Canelon, J.I.; Ortega, A.G. [Univ. del Zulia, Maracaibo, Zulia (Venezuela, Bolivarian Republic of). School of Electrical Engineering; Shieh, L.S. [Houston Univ., Houston, TX (United States). Dept. of Electrical and Computer Engineering; Bastidas, J.I. [Univ. del Zulia, Maracaibo, Zulia (Venezuela, Bolivarian Republic of). School of Mechanical Engineering; Zhang, Y.; Akujuobi, C.M. [Prairie View A and M Univ., Prairie View, TX (United States). Center of Excellence for Communication Systems Technology Research and Dept. of Engineering Technology

    2010-08-13

    For high power applications, hydraulic actuators offer many advantages over electromagnetic actuators, including higher torque/mass ratios; smaller control gains; excellent torque capability; filtered high frequency noise; better heat transfer characteristics; smaller size; higher speed of response of the servomechanism; cheaper hardware; and higher reliability. Therefore, any application that requires a large force applied smoothly by an actuator is a candidate for hydraulic power. Examples of such applications include vehicle steering and braking systems; roll mills; drilling rigs; heavy duty crane and presses; and industrial robots and actuators for aircraft control surfaces such as ailerons and flaps. It is extremely important to create effective control strategies for hydraulic systems. This paper outlined the real-time implementation of a neural network-based approach, for self-tuning control of the angular position of a nonlinear electro-hydraulic servomotor. Using an online training algorithm, a neural network autoregressive moving-average model with exogenous input (ARMAX) model of the system was identified and continuously updated and an optimal linear ARMAX model was determined. The paper briefly depicted the neural network-based self-tuning control approach and a description of the experimental equipment (hardware and software) was presented including the implementation details. The experimental results were discussed and conclusions were summarized. It was found that the approach proved to be very effective in the control of this fast dynamics system, outperforming a fine tuned PI controller. Therefore, although the self-tuning approach was computationally demanding, it was feasible for real-time implementation. 22 refs., 6 figs.

  14. Manual and automatic flight control during severe turbulence penetration

    Science.gov (United States)

    Johnston, D. E.; Klein, R. H.; Hoh, R. H.

    1976-01-01

    An analytical and experimental investigation of possible contributing factors in jet aircraft turbulence upsets was conducted. Major contributing factors identified included autopilot and display deficiencies, the large aircraft inertia and associated long response time, and excessive pilot workload. An integrated flight and thrust energy management director system was synthesized. The system was incorporated in a moving-base simulation and evaluated using highly experienced airline pilots. The evaluation included comparison of pilot workload and flight performance during severe turbulence penetration utilizing four control/display concepts: manual control with conventional full panel display, conventional autopilot (A/P-A) with conventional full panel display, improved autopilot (A/P-B) with conventional full panel display plus thrust director display, and longitudinal flight director with conventional full panel display plus thrust director display. Simulation results show improved performance, reduced pilot workload, and a pilot preference for the autopilot system controlling to the flight director command and manual control of thrust following the trim thrust director.

  15. Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control

    Directory of Open Access Journals (Sweden)

    L. Batet

    2007-11-01

    Full Text Available Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV. ANAV is the consortium that runs the Ascó power plants (2 units and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC thermal-hydraulic analysis team has jointly worked together with ANAV engineers at different levels in the analysis and improvement of these reactors. This article is an illustration of the usefulness of computational analysis for operational support. The contents presented were operational between 1985 and 2001 and subsequently changed slightly following various organizational adjustments. The paper has two different parts. In the first part, it describes the specific aspects of thermal-hydraulic analysis tasks related to operation and control and, in the second part, it briefly presents the results of three examples of analyses that were performed. All the presented examples are related to actual situations in which the scenarios were studied by analysts using thermal-hydraulic codes and prepared nodalizations. The paper also includes a qualitative evaluation of the benefits obtained by ANAV through thermal-hydraulic analyses aimed at supporting operation and plant control.

  16. Functional integration of vertical flight path and speed control using energy principles

    Science.gov (United States)

    Lambregts, A. A.

    1984-01-01

    A generalized automatic flight control system was developed which integrates all longitudinal flight path and speed control functions previously provided by a pitch autopilot and autothrottle. In this design, a net thrust command is computed based on total energy demand arising from both flight path and speed targets. The elevator command is computed based on the energy distribution error between flight path and speed. The engine control is configured to produce the commanded net thrust. The design incorporates control strategies and hierarchy to deal systematically and effectively with all aircraft operational requirements, control nonlinearities, and performance limits. Consistent decoupled maneuver control is achieved for all modes and flight conditions without outer loop gain schedules, control law submodes, or control function duplication.

  17. Design of the Driving and Clamp Rotation Hydraulic Control System for the Heavy Load Forging Manipulator

    Directory of Open Access Journals (Sweden)

    Li Geqiang

    2015-01-01

    Full Text Available The manipulator was equipped with full hydraulic drive. We designed the hydraulic systems for the driving and clamping rotation. We used a fuzzy PID control strategy to design the electro-hydraulic proportional control system. We built a united simulation model based on the co-simulation of MATLAB/Simulink and AMEsim. A mathematical model of the system was also established. We did separate simulations of the system’s dynamic characteristics for fast forging and normal forging working conditions. The parameters were optimized. The field test shows that the steady-state error of the hydraulic system is small and the system response is fast. The system’s rapid response speed, high precision, and stability under heavy load were realized.

  18. Monitoring Hydraulic Fracturing Using Ground-Based Controlled Source Electromagnetics

    Science.gov (United States)

    Hickey, M. S.; Trevino, S., III; Everett, M. E.

    2017-12-01

    Hydraulic fracturing allows hydrocarbon production in low permeability formations. Imaging the distribution of fluid used to create a hydraulic fracture can aid in the characterization of fracture properties such as extent of plume penetration as well as fracture azimuth and symmetry. This could contribute to improving the efficiency of an operation, for example, in helping to determine ideal well spacing or the need to refracture a zone. A ground-based controlled-source electromagnetics (CSEM) technique is ideal for imaging the fluid due to the change in field caused by the difference in the conductive properties of the fluid when compared to the background. With advances in high signal to noise recording equipment, coupled with a high-power, broadband transmitter we can show hydraulic fracture extent and azimuth with minimal processing. A 3D finite element code is used to model the complete well casing along with the layered subsurface. This forward model is used to optimize the survey design and isolate the band of frequencies with the best response. In the field, the results of the modeling are also used to create a custom pseudorandom numeric (PRN) code to control the frequencies transmitted through a grounded dipole source. The receivers record the surface voltage across two grounded dipoles, one parallel and one perpendicular to the transmitter. The data are presented as the displays of amplitude ratios across several frequencies with the associated spatial information. In this presentation, we show multiple field results in multiple basins in the United States along with the CSEM theory used to create the survey designs.

  19. Reduced-order model based active disturbance rejection control of hydraulic servo system with singular value perturbation theory.

    Science.gov (United States)

    Wang, Chengwen; Quan, Long; Zhang, Shijie; Meng, Hongjun; Lan, Yuan

    2017-03-01

    Hydraulic servomechanism is the typical mechanical/hydraulic double-dynamics coupling system with the high stiffness control and mismatched uncertainties input problems, which hinder direct applications of many advanced control approaches in the hydraulic servo fields. In this paper, by introducing the singular value perturbation theory, the original double-dynamics coupling model of the hydraulic servomechanism was reduced to a integral chain system. So that, the popular ADRC (active disturbance rejection control) technology could be directly applied to the reduced system. In addition, the high stiffness control and mismatched uncertainties input problems are avoided. The validity of the simplified model is analyzed and proven theoretically. The standard linear ADRC algorithm is then developed based on the obtained reduced-order model. Extensive comparative co-simulations and experiments are carried out to illustrate the effectiveness of the proposed method. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  20. Intelligent Flight Control Simulation Research Program

    National Research Council Canada - National Science Library

    Stolarik, Brian

    2007-01-01

    ...). Under the program, entitled "Intelligent Flight Control Simulation Research Laboratory," a variety of technologies were investigated or developed during the course of the research for AFRL/VAC...

  1. In-Flight Validation of a Pilot Rating Scale for Evaluating Failure Transients in Electronic Flight Control Systems

    Science.gov (United States)

    Kalinowski, Kevin F.; Tucker, George E.; Moralez, Ernesto, III

    2006-01-01

    Engineering development and qualification of a Research Flight Control System (RFCS) for the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH-60A has motivated the development of a pilot rating scale for evaluating failure transients in fly-by-wire flight control systems. The RASCAL RFCS includes a highly-reliable, dual-channel Servo Control Unit (SCU) to command and monitor the performance of the fly-by-wire actuators and protect against the effects of erroneous commands from the flexible, but single-thread Flight Control Computer. During the design phase of the RFCS, two piloted simulations were conducted on the Ames Research Center Vertical Motion Simulator (VMS) to help define the required performance characteristics of the safety monitoring algorithms in the SCU. Simulated failures, including hard-over and slow-over commands, were injected into the command path, and the aircraft response and safety monitor performance were evaluated. A subjective Failure/Recovery Rating (F/RR) scale was developed as a means of quantifying the effects of the injected failures on the aircraft state and the degree of pilot effort required to safely recover the aircraft. A brief evaluation of the rating scale was also conducted on the Army/NASA CH-47B variable stability helicopter to confirm that the rating scale was likely to be equally applicable to in-flight evaluations. Following the initial research flight qualification of the RFCS in 2002, a flight test effort was begun to validate the performance of the safety monitors and to validate their design for the safe conduct of research flight testing. Simulated failures were injected into the SCU, and the F/RR scale was applied to assess the results. The results validate the performance of the monitors, and indicate that the Failure/Recovery Rating scale is a very useful tool for evaluating failure transients in fly-by-wire flight control systems.

  2. Hydraulic manipulator research at ORNL

    International Nuclear Information System (INIS)

    Kress, R.L.; Jansen, J.F.; Love, L.J.

    1997-01-01

    Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL's flexible/prismatic test stand

  3. Hydraulic manipulator research at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States); Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

    1997-03-01

    Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL`s flexible/prismatic test stand.

  4. Virtual decoupling flight control via real-time trajectory synthesis and tracking

    Science.gov (United States)

    Zhang, Xuefu

    The production of the General Aviation industry has declined in the past 25 years. Ironically, however, the increasing demand for air travel as a fast, safe, and high-quality mode of transportation has been far from satisfied. Addressing this demand shortfall with personal air transportation necessitates advanced systems for navigation, guidance, control, flight management, and flight traffic control. Among them, an effective decoupling flight control system will not only improve flight quality, safety, and simplicity, and increase air space usage, but also reduce expenses on pilot initial and current training, and thus expand the current market and explore new markets. Because of the formidable difficulties encountered in the actual decoupling of non-linear, time-variant, and highly coupled flight control systems through traditional approaches, a new approach, which essentially converts the decoupling problem into a real-time trajectory synthesis and tracking problem, is employed. Then, the converted problem is solved and a virtual decoupling effect is achieved. In this approach, a trajectory in inertial space can be predefined and dynamically modified based on the flight mission and the pilot's commands. A feedforward-feedback control architecture is constructed to guide the airplane along the trajectory as precisely as possible. Through this approach, the pilot has much simpler, virtually decoupled control of the airplane in terms of speed, flight path angle and horizontal radius of curvature. To verify and evaluate this approach, extensive computer simulation is performed. A great deal of test cases are designed for the flight control under different flight conditions. The simulation results show that our decoupling strategy is satisfactory and promising, and therefore the research can serve as a consolidated foundation for future practical applications.

  5. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    Science.gov (United States)

    VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Orr, Jeb S.; Miller, Christopher J.; Hanson, Curtis E.

    2014-01-01

    The NASA Marshall Space Flight Center (MSFC) Flight Mechanics and Analysis Division developed an Adaptive Augmenting Control (AAC) algorithm for launch vehicles that improves robustness and performance by adapting an otherwise welltuned classical control algorithm to unexpected environments or variations in vehicle dynamics. This AAC algorithm is currently part of the baseline design for the SLS Flight Control System (FCS), but prior to this series of research flights it was the only component of the autopilot design that had not been flight tested. The Space Launch System (SLS) flight software prototype, including the adaptive component, was recently tested on a piloted aircraft at Dryden Flight Research Center (DFRC) which has the capability to achieve a high level of dynamic similarity to a launch vehicle. Scenarios for the flight test campaign were designed specifically to evaluate the AAC algorithm to ensure that it is able to achieve the expected performance improvements with no adverse impacts in nominal or nearnominal scenarios. Having completed the recent series of flight characterization experiments on DFRC's F/A-18, the AAC algorithm's capability, robustness, and reproducibility, have been successfully demonstrated. Thus, the entire SLS control architecture has been successfully flight tested in a relevant environment. This has increased NASA's confidence that the autopilot design is ready to fly on the SLS Block I vehicle and will exceed the performance of previous architectures.

  6. F-8 Digital Fly-by-Wire (DFBW) in flight over snow capped mountains

    Science.gov (United States)

    1973-01-01

    F-8 Digital Fly-by-Wire (DFBW) aircraft in flight over snow capped mountains. Externally identical to a standard Navy F-8C, this aircraft had its control system replaced initially by a primary system using an Apollo digital computer. The backup system used three analog computers. When the pilot moved the airplane's stick and rudder, electronic signals went to the computer, which would generate signals to move the control surfaces. The system was designed so that the digital fly-by-wire aircraft would handle almost identically to a standard F-8C. Later, in Phase 2, the aircraft used three IBM AP-101 computers for its flight control system. The F-8 Digital Fly-By-Wire (DFBW) flight research project validated the principal concepts of all-electric flight control systems now used on nearly all modern high-performance aircraft and on military and civilian transports. The first flight of the 13-year project was on May 25, 1972, with research pilot Gary E. Krier at the controls of a modified F-8C Crusader that served as the testbed for the fly-by-wire technologies. The project was a joint effort between the NASA Flight Research Center, Edwards, California, (now the Dryden Flight Research Center) and Langley Research Center. It included a total of 211 flights. The last flight was December 16, 1985, with Dryden research pilot Ed Schneider at the controls. The F-8 DFBW system was the forerunner of current fly-by-wire systems used in the space shuttles and on today's military and civil aircraft to make them safer, more maneuverable, and more efficient. Electronic fly-by-wire systems replaced older hydraulic control systems, freeing designers to design aircraft with reduced in-flight stability. Fly-by-wire systems are safer because of their redundancies. They are more maneuverable because computers can command more frequent adjustments than a human pilot can. For airliners, computerized control ensures a smoother ride than a human pilot alone can provide. Digital

  7. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    Science.gov (United States)

    Kim, Gi-Woo; Wang, K. W.

    2007-04-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system has many limitations. For example, the oil pump and valve body are relatively heavy and complex. Also, the oil pumps induce inherently large drag torque, which affects fuel economy. This research is to overcome these problems of the current system by exploring the utilization of a hybrid type piezo-hydraulic pump device for AT band brake control. This new actuating system integrates a piezo-hydraulic pump to the input of the band brake. Compared with the current systems, this new actuator features much simpler structure, smaller size, and lower weight. This paper describes the development, design and fabrication of the new stand-alone prototype actuator for AT band brake control. An analytical model is developed and validated using experimental data. Performance tests on the hardware and system simulations utilizing the validated model are performed to characterize the new prototype actuator. It is predicted that with increasing of accumulator pressure and driving frequency, the proposed prototype actuating system will satisfy the band brake requirement for AT shift control.

  8. F-15 837 IFCS Intelligent Flight Control System Project

    Science.gov (United States)

    Bosworth, John T.

    2007-01-01

    This viewgraph presentation reviews the use of Intelligent Flight Control System (IFCS) for the F-15. The goals of the project are: (1) Demonstrate Revolutionary Control Approaches that can Efficiently Optimize Aircraft Performance in both Normal and Failure Conditions (2) Advance Neural Network-Based Flight Control Technology for New Aerospace Systems Designs. The motivation for the development are to reduce the chance and skill required for survival.

  9. On Application of Second Order Sliding Mode Control to Electro-Hydraulic Systems

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2014-01-01

    This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive...

  10. Development of control system of coating of rod hydraulic cylinders

    Science.gov (United States)

    Aizhambaeva, S. Zh; Maximova, A. V.

    2018-01-01

    In this article, requirements to materials of hydraulic cylinders and methods of eliminating the main factors affecting the quality of the applied coatings rod hydraulic cylinders. The chromium plating process - one of ways of increase of anti-friction properties of coatings rods, stability to the wear and corrosion. The article gives description of differences of the stand-speed chromium plating process from other types of chromium plating that determines a conclusion about cutting time of chromium plating process. Conducting the analysis of technological equipment suggested addressing the modernization of high-speed chromium plating processes by automation and mechanization. Control system developed by design of schematic block diagram of a modernized and stand-speed chromium plating process.

  11. Model-based servo hydraulic control of a continuously variable transmission

    NARCIS (Netherlands)

    Cools, S.J.M.; Veenhuizen, P.A.; Pauwelussen, J.P.

    2004-01-01

    In order to reduce the power consumption of a transmission, maximum tracking accuracy should be achieved of both ratio and pressures in the variator. A control strategy is proposed to steer a variator, actuated with a newly developed hydraulic system, of a Continuously Variable Transmission (CVT).

  12. Pilot-in-the-Loop Analysis of Propulsive-Only Flight Control Systems

    Science.gov (United States)

    Chou, Hwei-Lan; Biezad, Daniel J.

    1996-01-01

    Longitudinal control system architectures are presented which directly couple flight stick motions to throttle commands for a multi-engine aircraft. This coupling enables positive attitude control with complete failure of the flight control system. The architectures chosen vary from simple feedback gains to classical lead-lag compensators with and without prefilters. Each architecture is reviewed for its appropriateness for piloted flight. The control systems are then analyzed with pilot-in-the-loop metrics related to bandwidth required for landing. Results indicate that current and proposed bandwidth requirements should be modified for throttles only flight control. Pilot ratings consistently showed better ratings than predicted by analysis. Recommendations are made for more robust design and implementation. The use of Quantitative Feedback Theory for compensator design is discussed. Although simple and effective augmented control can be achieved in a wide variety of failed configurations, a few configuration characteristics are dominant for pilot-in-the-loop control. These characteristics will be tested in a simulator study involving failed flight controls for a multi-engine aircraft.

  13. HYDRAULIC CONCRETE COMPOSITION AND PROPERTIES CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    O. M. Pshinko

    2015-08-01

    Full Text Available Purpose. Scientific work aims at the development and testing of information system to meet the challenges of concrete composition design and control (for railway structures and buildings based on the physico-analytical method algorithm for hydraulic concrete composition calculation. Methodology. The proposed algorithm of hydraulic concrete composition calculation is based on the physicochemical mechanics and in particular on the rheology of elastic–viscous–plastic bodies. The system of canonical equations consists of the equations for concrete strength, absolute volume, concrete mix consistency as well as the equation for optimal concrete saturation with aggregates while minimizing cement content. The joint solution of these four equations related to composition allows determining for the materials the concrete composition of required strength, concrete workability with minimum cement content. The procedure for calculation of hydraulic concrete composition according to the physico-analytical method consists of two parts: 1 physical, which is laboratory testing of concrete mix components in different concrete compositions; 2 analytical, which represents the calculation algorithm for concrete compositions equivalent in concrete strength and workability that comply with the specific conditions of concrete placing. Findings. To solve the problem of designing the concrete composition with the desired properties for railway structures and buildings it was proposed to use the information technology in the form of a developed computer program whose algorithm includes the physico-analytical method for hydraulic concrete composition determination. Originality. The developed concrete composition design method takes into account the basic properties of raw materials, concrete mix and concrete, which are pre-determined. The distinctive feature of physico-analytical method is obtaining of a set of equivalent compositions with a certain concrete mix

  14. Development of An Intelligent Flight Propulsion Control System

    Science.gov (United States)

    Calise, A. J.; Rysdyk, R. T.; Leonhardt, B. K.

    1999-01-01

    The initial design and demonstration of an Intelligent Flight Propulsion and Control System (IFPCS) is documented. The design is based on the implementation of a nonlinear adaptive flight control architecture. This initial design of the IFPCS enhances flight safety by using propulsion sources to provide redundancy in flight control. The IFPCS enhances the conventional gain scheduled approach in significant ways: (1) The IFPCS provides a back up flight control system that results in consistent responses over a wide range of unanticipated failures. (2) The IFPCS is applicable to a variety of aircraft models without redesign and,(3) significantly reduces the laborious research and design necessary in a gain scheduled approach. The control augmentation is detailed within an approximate Input-Output Linearization setting. The availability of propulsion only provides two control inputs, symmetric and differential thrust. Earlier Propulsion Control Augmentation (PCA) work performed by NASA provided for a trajectory controller with pilot command input of glidepath and heading. This work is aimed at demonstrating the flexibility of the IFPCS in providing consistency in flying qualities under a variety of failure scenarios. This report documents the initial design phase where propulsion only is used. Results confirm that the engine dynamics and associated hard nonlineaaities result in poor handling qualities at best. However, as demonstrated in simulation, the IFPCS is capable of results similar to the gain scheduled designs of the NASA PCA work. The IFPCS design uses crude estimates of aircraft behaviour. The adaptive control architecture demonstrates robust stability and provides robust performance. In this work, robust stability means that all states, errors, and adaptive parameters remain bounded under a wide class of uncertainties and input and output disturbances. Robust performance is measured in the quality of the tracking. The results demonstrate the flexibility of

  15. 14 CFR 417.415 - Post-launch and post-flight-attempt hazard controls.

    Science.gov (United States)

    2010-01-01

    ...-flight-attempt hazard controls. (a) A launch operator must establish, maintain and perform procedures for... system operation. The flight termination system receivers must remain captured by the command control... launch operator must establish procedural controls for hazards associated with an unsuccessful flight...

  16. Application of nonlinear transformations to automatic flight control

    Science.gov (United States)

    Meyer, G.; Su, R.; Hunt, L. R.

    1984-01-01

    The theory of transformations of nonlinear systems to linear ones is applied to the design of an automatic flight controller for the UH-1H helicopter. The helicopter mathematical model is described and it is shown to satisfy the necessary and sufficient conditions for transformability. The mapping is constructed, taking the nonlinear model to canonical form. The performance of the automatic control system in a detailed simulation on the flight computer is summarized.

  17. An approach for second order control with finite time convergence for electro-hydraulic drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    algorithm parameters. However a discontinuous term internally in the control structure may excite pressures of transmission lines in hydraulic drives as the control structure strives to maintain the control error and its derivative equal to zero. In this paper a modified version of a controller based......Being a second order sliding algorithm, the super twisting algorithm is highly attractive for application in control of hydraulic drives and mechanical systems in general, as it utilizes only the control error while driving the control error as well as its derivative to zero for properly chosen...... on the super twisting algorithm is proposed, with the focus of eliminating the discontinuous term in order to achieve a more smooth control operation. The convergence properties of the proposed controller are analyzed via a conservative phase plane analysis. Furthermore, homogeneity considerations imply finite...

  18. Effect of video-game experience and position of flight stick controller on simulated-flight performance.

    Science.gov (United States)

    Cho, Bo-Keun; Aghazadeh, Fereydoun; Al-Qaisi, Saif

    2012-01-01

    The purpose of this study was to determine the effects of video-game experience and flight-stick position on flying performance. The study divided participants into 2 groups; center- and side-stick groups, which were further divided into high and low level of video-game experience subgroups. The experiment consisted of 7 sessions of simulated flying, and in the last session, the flight stick controller was switched to the other position. Flight performance was measured in terms of the deviation of heading, altitude, and airspeed from their respective requirements. Participants with high experience in video games performed significantly better (p increase (0.78 %). However, after switching from a center- to a side-stick controller, performance scores decreased (4.8%).

  19. Flight Test of L1 Adaptive Control Law: Offset Landings and Large Flight Envelope Modeling Work

    Science.gov (United States)

    Gregory, Irene M.; Xargay, Enric; Cao, Chengyu; Hovakimyan, Naira

    2011-01-01

    This paper presents new results of a flight test of the L1 adaptive control architecture designed to directly compensate for significant uncertain cross-coupling in nonlinear systems. The flight test was conducted on the subscale turbine powered Generic Transport Model that is an integral part of the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. The results presented include control law evaluation for piloted offset landing tasks as well as results in support of nonlinear aerodynamic modeling and real-time dynamic modeling of the departure-prone edges of the flight envelope.

  20. Hydraulic system for the drive of control rod

    International Nuclear Information System (INIS)

    Niwano, Masao.

    1978-01-01

    Purpose: To remove thermal stress and improve safety by utilizing water discharged a driving device as a part of cooling water for the device upon driving of control rods. Constitution: A water drain valve is wholly closed and a flow stabilization valve is supplied with an amount of water necessary for driving control rods. Upon driving one control rod, an amount of water required for the driving is caused to flow to the relivant hydraulic control unit and the flow rate in the stabilization valve is reduced by an amount required for the driving to keep the flow rate constant in the flow control valve. Since Excess water conventionally returned to the pressure vessel is utilized as cooling water for the driving device of control rods, the pressure vessel nozzle can be saved. Accordingly, the thermal stress in the nozzle portion can be removed to significantly improve the safety. (Seki, T.)

  1. Intelligent Flight Control System and Aeronautics Research at NASA Dryden

    Science.gov (United States)

    Brown, Nelson A.

    2009-01-01

    This video presentation reviews the F-15 Intelligent Flight Control System and contains clips of flight tests and aircraft performance in the areas of target tracking, takeoff and differential stabilators. Video of the APG milestone flight 1g formation is included.

  2. EKF-based fault detection for guided missiles flight control system

    Science.gov (United States)

    Feng, Gang; Yang, Zhiyong; Liu, Yongjin

    2017-03-01

    The guided missiles flight control system is essential for guidance accuracy and kill probability. It is complicated and fragile. Since actuator faults and sensor faults could seriously affect the security and reliability of the system, fault detection for missiles flight control system is of great significance. This paper deals with the problem of fault detection for the closed-loop nonlinear model of the guided missiles flight control system in the presence of disturbance. First, set up the fault model of flight control system, and then design the residual generation based on the extended Kalman filter (EKF) for the Eulerian-discrete fault model. After that, the Chi-square test was selected for the residual evaluation and the fault detention task for guided missiles closed-loop system was accomplished. Finally, simulation results are provided to illustrate the effectiveness of the approach proposed in the case of elevator fault separately.

  3. Using Engine Thrust for Emergency Flight Control: MD-11 and B-747 Results

    Science.gov (United States)

    Burcham, Frank W., Jr.; Maine, Trindel A.; Burken, John J.; Bull, John

    1998-01-01

    With modern digital control systems, using engine thrust for emergency flight control to supplement or replace failed aircraft normal flight controls has become a practical consideration. The NASA Dryden Flight Research Center has developed a propulsion-controlled aircraft (PCA) system in which computer-controlled engine thrust provides emergency flight control. An F-15 and an MD-11 airplane have been landed without using any flight control surfaces. Preliminary studies have also been conducted that show that engines on only one wing can provide some flight control capability if the lateral center of gravity can be shifted toward the side of the airplane that has the operating engine(s). Simulator tests of several airplanes with no flight control surfaces operating and all engines out on the left wing have all shown positive control capability within the available range of lateral center-of-gravity offset. Propulsion-controlled aircraft systems that can operate without modifications to engine control systems, thus allowing PCA technology to be installed on less capable airplanes or at low cost, are also desirable. Further studies have examined simplified 'PCA Lite' and 'PCA Ultralite' concepts in which thrust control is provided by existing systems such as auto-throttles or a combination of existing systems and manual pilot control.

  4. 76 FR 14795 - Special Conditions: Gulfstream Model GVI Airplane; Electronic Flight Control System Mode...

    Science.gov (United States)

    2011-03-18

    ... electronic flight control system. The applicable airworthiness regulations do not contain adequate or...). Novel or Unusual Design Features The GVI will have a fly-by-wire electronic flight control system. This system provides an electronic interface between the pilot's flight controls and the flight control...

  5. A hybrid flight control for a simulated raptor-30 v2 helicopter

    International Nuclear Information System (INIS)

    Khizer, A.N.

    2015-01-01

    This paper presents a hybrid flight control system for a single rotor simulated Raptor-30 V2 helicopter. Hybrid intelligent control system, combination of the conventional and intelligent control methodologies, is applied to small model helicopter. The proposed hybrid control used PID as a traditional control and fuzzy as an intelligent control so as to take the maximum advantage of advanced control theory. The helicopter model used; comes from X-Plane flight simulator and their hybrid flight control system was simulated using MATLAB/SIMULINK in a simulation platform. X-Plane is also used to visualize the performance of this proposed autopilot design. Through a series of numerous experiments, the operation of hybrid control system was investigated. Results verified that the proposed hybrid control has an excellent performance at hovering flight mode. (author)

  6. Adaptive Neural Network Control for Nonlinear Hydraulic Servo-System with Time-Varying State Constraints

    Directory of Open Access Journals (Sweden)

    Shu-Min Lu

    2017-01-01

    Full Text Available An adaptive neural network control problem is addressed for a class of nonlinear hydraulic servo-systems with time-varying state constraints. In view of the low precision problem of the traditional hydraulic servo-system which is caused by the tracking errors surpassing appropriate bound, the previous works have shown that the constraint for the system is a good way to solve the low precision problem. Meanwhile, compared with constant constraints, the time-varying state constraints are more general in the actual systems. Therefore, when the states of the system are forced to obey bounded time-varying constraint conditions, the high precision tracking performance of the system can be easily realized. In order to achieve this goal, the time-varying barrier Lyapunov function (TVBLF is used to prevent the states from violating time-varying constraints. By the backstepping design, the adaptive controller will be obtained. A radial basis function neural network (RBFNN is used to estimate the uncertainties. Based on analyzing the stability of the hydraulic servo-system, we show that the error signals are bounded in the compacts sets; the time-varying state constrains are never violated and all singles of the hydraulic servo-system are bounded. The simulation and experimental results show that the tracking accuracy of system is improved and the controller has fast tracking ability and strong robustness.

  7. Mentoring SFRM: A New Approach to International Space Station Flight Control Training

    Science.gov (United States)

    Huning, Therese; Barshi, Immanuel; Schmidt, Lacey

    2009-01-01

    The Mission Operations Directorate (MOD) of the Johnson Space Center is responsible for providing continuous operations support for the International Space Station (ISS). Operations support requires flight controllers who are skilled in team performance as well as the technical operations of the ISS. Space Flight Resource Management (SFRM), a NASA adapted variant of Crew Resource Management (CRM), is the competency model used in the MOD. ISS flight controller certification has evolved to include a balanced focus on development of SFRM and technical expertise. The latest challenge the MOD faces is how to certify an ISS flight controller (Operator) to a basic level of effectiveness in 1 year. SFRM training uses a twopronged approach to expediting operator certification: 1) imbed SFRM skills training into all Operator technical training and 2) use senior flight controllers as mentors. This paper focuses on how the MOD uses senior flight controllers as mentors to train SFRM skills.

  8. Combining control input with flight path data to evaluate pilot performance in transport aircraft.

    Science.gov (United States)

    Ebbatson, Matt; Harris, Don; Huddlestone, John; Sears, Rodney

    2008-11-01

    When deriving an objective assessment of piloting performance from flight data records, it is common to employ metrics which purely evaluate errors in flight path parameters. The adequacy of pilot performance is evaluated from the flight path of the aircraft. However, in large jet transport aircraft these measures may be insensitive and require supplementing with frequency-based measures of control input parameters. Flight path and control input data were collected from pilots undertaking a jet transport aircraft conversion course during a series of symmetric and asymmetric approaches in a flight simulator. The flight path data were analyzed for deviations around the optimum flight path while flying an instrument landing approach. Manipulation of the flight controls was subject to analysis using a series of power spectral density measures. The flight path metrics showed no significant differences in performance between the symmetric and asymmetric approaches. However, control input frequency domain measures revealed that the pilots employed highly different control strategies in the pitch and yaw axes. The results demonstrate that to evaluate pilot performance fully in large aircraft, it is necessary to employ performance metrics targeted at both the outer control loop (flight path) and the inner control loop (flight control) parameters in parallel, evaluating both the product and process of a pilot's performance.

  9. Implementasi Prototype Alat Uji Flight Control Actuator Pesawat Berbasis Mikrokontroller Arduino Uno

    Directory of Open Access Journals (Sweden)

    NANDANG TARYANA

    2018-02-01

    Full Text Available ABSTRAK Flight control system merupakan suatu sistem di pesawat udara yang digunakan untuk manuver dari satu kondisi terbang ke kondisi terbang lainnya. Alat uji flight control actuator pesawat ini dirancang berupa prototype yang dikendalikan dengan menggunakan mikrokontroller arduino uno, yang terdiri dari input dan output. Input tersebut adalah sensor load cell yang berfungsi untuk mengetahui beban yang diterima dari aktuator pesawat, serta input sensor ping berfungsi untuk mengetahui jarak ataupun sudut dari pergerakan aktuator pesawat. Sedangkan output yang dihasilkan berupa data dari hasil pembacaan sensor load cell dan sensor ping. Alat uji flight control sistem aktuator pesawat yang telah direalisasikan mampu menggerakkan 2 buah double acting cylinder untuk bekerja naik dan turun secara bergantian serta mampu menggerakkan motor servo dengan jarak pergerakkan 3 cm – 4 cm. Kata kunci: Flight control system, Arduino Uno, double acting cylinder, Sensor Ping, Load Cell, Motor Servo ABSTRACT Flight control system is a system in which aircraft are used to maneuver from one condition to fly to other flight conditions. Testing instruments aircraft flight control actuator designed a prototype of which is controlled by using microcontroller arduino uno, which consists of input and output. The input is a load cell sensor that serves to determine the load received from aircraft actuators, as well as ping sensor input is used to determine the distance or angle of the aircraft actuator movement . While the output of the data from the load cell sensor readings and sensor ping . Test equipment aircraft flight control actuator system that has been realized is able to move two pieces of double acting cylinder to work up and down alternately and able to drive the servo motor with the movement distance of 3 cm – 4 cm . Keywords: Flight control system , Arduino Uno , double acting cylinder , Ping Sensor, Load Cell, Servo Motor

  10. Control design and optimization for the DOT500 hydraulic wind turbine

    NARCIS (Netherlands)

    Mulders, S.P.; Jager, Stéphane; Diepeveen, N.F.B.; van Wingerden, J.W.

    2017-01-01

    The drivetrain of most wind turbines currently being deployed commercially consists of a rotor-gearboxgenerator configuration in the nacelle. This abstract introduces the control system design and optimization for a wind turbine with a hydraulic drivetrain, based on the Delft Offshore Turbine (DOT)

  11. Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control

    International Nuclear Information System (INIS)

    You, Seung Han; Hahn, Jin Oh

    2012-01-01

    By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today's passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems

  12. Integrated controls pay-off. [for flight/propulsion aircraft systems

    Science.gov (United States)

    Putnam, Terrill W.; Christiansen, Richard S.

    1989-01-01

    It is shown that the integration of the propulsion and flight control systems for high performance aircraft can help reduce pilot workload while simultaneously increasing overall aircraft performance. Results of the Highly Integrated Digital Electronic Control (HiDEC) flight research program are presented to demonstrate the emerging payoffs of controls integration. Ways in which the performance of fighter aircraft can be improved through the use of propulsion for primary aircraft control are discussed. Research being conducted by NASA with the F-18 High Angle-of Attack Research Vehicle is described.

  13. Space Launch System Ascent Flight Control Design

    Science.gov (United States)

    Orr, Jeb S.; Wall, John H.; VanZwieten, Tannen S.; Hall, Charles E.

    2014-01-01

    A robust and flexible autopilot architecture for NASA's Space Launch System (SLS) family of launch vehicles is presented. The SLS configurations represent a potentially significant increase in complexity and performance capability when compared with other manned launch vehicles. It was recognized early in the program that a new, generalized autopilot design should be formulated to fulfill the needs of this new space launch architecture. The present design concept is intended to leverage existing NASA and industry launch vehicle design experience and maintain the extensibility and modularity necessary to accommodate multiple vehicle configurations while relying on proven and flight-tested control design principles for large boost vehicles. The SLS flight control architecture combines a digital three-axis autopilot with traditional bending filters to support robust active or passive stabilization of the vehicle's bending and sloshing dynamics using optimally blended measurements from multiple rate gyros on the vehicle structure. The algorithm also relies on a pseudo-optimal control allocation scheme to maximize the performance capability of multiple vectored engines while accommodating throttling and engine failure contingencies in real time with negligible impact to stability characteristics. The architecture supports active in-flight disturbance compensation through the use of nonlinear observers driven by acceleration measurements. Envelope expansion and robustness enhancement is obtained through the use of a multiplicative forward gain modulation law based upon a simple model reference adaptive control scheme.

  14. System and method for controlling engine knock using electro-hydraulic valve actuation

    Science.gov (United States)

    Brennan, Daniel G

    2013-12-10

    A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

  15. Fault Tolerant Flight Control Using Sliding Modes and Subspace Identification-Based Predictive Control

    KAUST Repository

    Siddiqui, Bilal A.; El-Ferik, Sami; Abdelkader, Mohamed

    2016-01-01

    In this work, a cascade structure of a time-scale separated integral sliding mode and model predictive control is proposed as a viable alternative for fault-tolerant control. A multi-variable sliding mode control law is designed as the inner loop of the flight control system. Subspace identification is carried out on the aircraft in closed loop. The identified plant is then used for model predictive controllers in the outer loop. The overall control law demonstrates improved robustness to measurement noise, modeling uncertainties, multiple faults and severe wind turbulence and gusts. In addition, the flight control system employs filters and dead-zone nonlinear elements to reduce chattering and improve handling quality. Simulation results demonstrate the efficiency of the proposed controller using conventional fighter aircraft without control redundancy.

  16. Fault Tolerant Flight Control Using Sliding Modes and Subspace Identification-Based Predictive Control

    KAUST Repository

    Siddiqui, Bilal A.

    2016-07-26

    In this work, a cascade structure of a time-scale separated integral sliding mode and model predictive control is proposed as a viable alternative for fault-tolerant control. A multi-variable sliding mode control law is designed as the inner loop of the flight control system. Subspace identification is carried out on the aircraft in closed loop. The identified plant is then used for model predictive controllers in the outer loop. The overall control law demonstrates improved robustness to measurement noise, modeling uncertainties, multiple faults and severe wind turbulence and gusts. In addition, the flight control system employs filters and dead-zone nonlinear elements to reduce chattering and improve handling quality. Simulation results demonstrate the efficiency of the proposed controller using conventional fighter aircraft without control redundancy.

  17. Flight Tests of a Ministick Controller in an F/A-18 Airplane

    Science.gov (United States)

    Stoliker, Patrick C.; Carter, John

    2003-01-01

    In March of 1999, five pilots performed flight tests to evaluate the handling qualities of an F/A-18 research airplane equipped with a small-displacement center stick (ministick) controller that had been developed for the JAS 39 Gripen airplane (a fighter/attack/ reconnaissance airplane used by the Swedish air force). For these tests, the ministick was installed in the aft cockpit (see figure) and production support flight control computers (PSFCCs) were used as interfaces between the controller hardware and the standard F/A-18 flight-control laws. The primary objective of the flight tests was to assess any changes in handling qualities of the F/A-18 airplane attributable to the mechanical characteristics of the ministick. The secondary objective was to demonstrate the capability of the PSFCCs to support flight-test experiments.

  18. Multimodel Predictive Control Approach for UAV Formation Flight

    Directory of Open Access Journals (Sweden)

    Chang-jian Ru

    2014-01-01

    Full Text Available Formation flight problem is the most important and interesting problem of multiple UAVs (unmanned aerial vehicles cooperative control. In this paper, a novel approach for UAV formation flight based on multimodel predictive control is designed. Firstly, the state equation of relative motion is obtained and then discretized. By the geometrical method, the characteristic points of state are determined. Afterwards, based on the linearization technique, the standard linear discrete model is obtained at each characteristic state point. Then, weighted model set is proposed using the idea of T-S (Takagi-Sugeno fuzzy control and the predictive control is carried out based on the multimodel method. Finally, to verify the performance of the proposed method, two different simulation scenarios are performed.

  19. Neutron radiography of aircraft composite flight control surfaces

    International Nuclear Information System (INIS)

    Lewis, W.J.; Bennett, L.G.I.; Chalovich, T.R.; Francescone, O.

    2001-01-01

    A small (20 kWth), safe, pool-type nuclear research reactor called the SLOWPOKE-2 is located at the Royal Military College of Canada (RMC). The reactor was originally installed for teaching, training, research and semi-routine analysis, specifically, neutron activation analysis. It was envisioned that the neutrons from the SLOWPOKE-2 could also be used for neutron radiography, and so a research program was initiated to develop this technology. Over a period of approximately 15 years, and through a series of successive modifications, a neutron radiography system (NRS) was developed. Once completed, several applications of the technology have been demonstrated, including the nondestructive examination of the composite flight control surfaces from the Canadian Air Force's primary jet fighter, the CF18 Hornet aircraft. An initial trial was setup to investigate the flight control surfaces of 3 aircraft, to determine the parameters for a final licensed system, and to compare the results to other nondestructive methods. Over 500 neutron radiographs were made for these first 3 aircraft, and moisture and corrosion were discovered in the honeycomb structure and hydration was found in the composite and adhesive layers. In comparison with other NDT methods, neutron radiography was the only method that could detect the small areas of corrosion and moisture entrapment. However, before examining an additional 7 aircraft, the recommended modifications to the NRS were undertaken. These modifications were necessary to accommodate the larger flight control surfaces safely by incorporating flexible conformable shielding. As well, to expedite inspections so that all flight control surfaces from one aircraft could be completed in less than two weeks, there was a need to decrease the exposure time by both faster film/conversion screen combinations and by incorporating the capability of near realtime, digital radioscopy. Finally, as there are no inspection specific image quality

  20. Numerical calculation for flow field of servo-tube guided hydraulic control rod driving system

    International Nuclear Information System (INIS)

    He Keyu; Han Weishi

    2010-01-01

    A new-style hydraulic control rod driving mechanism was put forward by using servo-tube control elements for the design of control rod driving mechanism. The results of numerical simulation by CFD program Fluent for flow field of hydraulic driving cylinder indicate that the bigger the outer diameter of servo-tube, the smaller the resistance coefficient of variable throttle orifice. The zero position gap of variable throttle orifice could be determined on 0.2 mm in the design. The pressure difference between the upper and nether surfaces of piston was mainly created by the throttle function of fixed throttle orifice. It can be effectively controlled by changing the gap of variable throttle orifice. And the lift force of driving cylinder is able to meet the requirement on the design load. (authors)

  1. Design Criteria for the Future of Flight Controls. Proceedings of the Flight Dynamics Laboratory Flying Qualities and Flight Control Symposium 2-5 March 1982.

    Science.gov (United States)

    1982-07-01

    launch platform . But as a transport, obviously, long duration flights must be accomplished without undue crew fatigue. Underlying all this is an...Modes a weapons platforme throah sore effective flight listed in Figure 1. control design. VII. Sugestd Frthr Research Rfrne There are certain...A KIat KiOW CC~~i at Pilot m1A~ MloU. ftm of a h m ad ftf trn* weD kqr~&~ m Wix a I -n ** Wuma of Am 1 Tbalam, ad axazw Dpi c Fwa PltwsAp ad A

  2. Review on flight simulators (today and tomorrow); Flight simulatior no genjo to kongo

    Energy Technology Data Exchange (ETDEWEB)

    Komura, T. [Mitsubishi Precision Company Limited, Tokyo (Japan)

    2000-04-05

    This paper presents various flight simulators. A flight simulator is classified into that for R and D on aircraft and that for flight training according to its usage. As an example of the former, the general-purpose flight simulation test facility of National Aerospace Laboratory, Science and Technology Agency is in use for development of the STOL experimental aircraft 'Asuka' and simulation experiments for space development. A civil aircraft simulator simulating the interior of a cockpit, operation feeling of piloting devices, flight performance, dynamic characteristics, an engine system and a hydraulic system like a real aircraft is in wide use for training pilots. A fighter simulator for air force is used for training detection of enemy's aircraft by radar, and missile shooting. An antisubmarine patrol aircraft simulator is used for training detection of submarines by sonic detector and magnetic detector, and torpedo air-launching. For both simulators, real simulation of detection sensors or battle environment is required. (NEDO)

  3. In-flight performance optimization for rotorcraft with redundant controls

    Science.gov (United States)

    Ozdemir, Gurbuz Taha

    A conventional helicopter has limits on performance at high speeds because of the limitations of main rotor, such as compressibility issues on advancing side or stall issues on retreating side. Auxiliary lift and thrust components have been suggested to improve performance of the helicopter substantially by reducing the loading on the main rotor. Such a configuration is called the compound rotorcraft. Rotor speed can also be varied to improve helicopter performance. In addition to improved performance, compound rotorcraft and variable RPM can provide a much larger degree of control redundancy. This additional redundancy gives the opportunity to further enhance performance and handling qualities. A flight control system is designed to perform in-flight optimization of redundant control effectors on a compound rotorcraft in order to minimize power required and extend range. This "Fly to Optimal" (FTO) control law is tested in simulation using the GENHEL model. A model of the UH-60, a compound version of the UH-60A with lifting wing and vectored thrust ducted propeller (VTDP), and a generic compound version of the UH-60A with lifting wing and propeller were developed and tested in simulation. A model following dynamic inversion controller is implemented for inner loop control of roll, pitch, yaw, heave, and rotor RPM. An outer loop controller regulates airspeed and flight path during optimization. A Golden Section search method was used to find optimal rotor RPM on a conventional helicopter, where the single redundant control effector is rotor RPM. The FTO builds off of the Adaptive Performance Optimization (APO) method of Gilyard by performing low frequency sweeps on a redundant control for a fixed wing aircraft. A method based on the APO method was used to optimize trim on a compound rotorcraft with several redundant control effectors. The controller can be used to optimize rotor RPM and compound control effectors through flight test or simulations in order to

  4. Propulsion/flight control integration technology (PROFIT) software system definition

    Science.gov (United States)

    Carlin, C. M.; Hastings, W. J.

    1978-01-01

    The Propulsion Flight Control Integration Technology (PROFIT) program is designed to develop a flying testbed dedicated to controls research. The control software for PROFIT is defined. Maximum flexibility, needed for long term use of the flight facility, is achieved through a modular design. The Host program, processes inputs from the telemetry uplink, aircraft central computer, cockpit computer control and plant sensors to form an input data base for use by the control algorithms. The control algorithms, programmed as application modules, process the input data to generate an output data base. The Host program formats the data for output to the telemetry downlink, the cockpit computer control, and the control effectors. Two applications modules are defined - the bill of materials F-100 engine control and the bill of materials F-15 inlet control.

  5. Design and simulation of flight control system for man-portable micro reconnaissance quadcopter

    Science.gov (United States)

    Yin, Xinfan; Zhang, Daibing; Fang, Qiang; Shen, Lincheng

    2017-10-01

    The quadcopter has been widely used in the field of aerial photography and environmental detection, because of its advantages of VTOL, simple structure, and easy-control. In the field of urban anti-terrorism or special operations, micro reconnaissance quadcpter has its unique advantages such as all-weather taking off and landing, small noise and so on, and it is very popular with special forces and riot police. This paper aims at the flight control problem of the micro quadcopter, for the purposes of attitude stabilization control and trajectory tracking control of the micro quadcopter, first, the modeling of the micro quadcopter is presented. And using the MATLAB/SIMULINK toolbox to build the flight controller of the micro quadcopter, and then simulation analysis and real flight test are given. The results of the experiment show that the designed PID controller can correct the flight attitude shift effectively and track the planned tracks well, and can achieve the goal of stable and reliable flight of the quadcopter. It can be a useful reference for the flight control system design of future special operations micro UAV.

  6. The Effectiveness of Yoga on Spiritual Intelligence in Air Traffic Controllers of Tehran Flight Control Center

    Science.gov (United States)

    Safara, Maryam; Ghasemi, Pejman

    2017-01-01

    The aim of this study was to evaluate the efficacy of yoga on spiritual intelligence in air traffic controllers in Tehran flight control center. This was a quasi-experimental research and the study population includes all air traffic controllers in Tehran flight control center. The sample consisted of 40 people of the study population that were…

  7. New experimental approaches to the biology of flight control systems.

    Science.gov (United States)

    Taylor, Graham K; Bacic, Marko; Bomphrey, Richard J; Carruthers, Anna C; Gillies, James; Walker, Simon M; Thomas, Adrian L R

    2008-01-01

    Here we consider how new experimental approaches in biomechanics can be used to attain a systems-level understanding of the dynamics of animal flight control. Our aim in this paper is not to provide detailed results and analysis, but rather to tackle several conceptual and methodological issues that have stood in the way of experimentalists in achieving this goal, and to offer tools for overcoming these. We begin by discussing the interplay between analytical and empirical methods, emphasizing that the structure of the models we use to analyse flight control dictates the empirical measurements we must make in order to parameterize them. We then provide a conceptual overview of tethered-flight paradigms, comparing classical ;open-loop' and ;closed-loop' setups, and describe a flight simulator that we have recently developed for making flight dynamics measurements on tethered insects. Next, we provide a conceptual overview of free-flight paradigms, focusing on the need to use system identification techniques in order to analyse the data they provide, and describe two new techniques that we have developed for making flight dynamics measurements on freely flying birds. First, we describe a technique for obtaining inertial measurements of the orientation, angular velocity and acceleration of a steppe eagle Aquila nipalensis in wide-ranging free flight, together with synchronized measurements of wing and tail kinematics using onboard instrumentation and video cameras. Second, we describe a photogrammetric method to measure the 3D wing kinematics of the eagle during take-off and landing. In each case, we provide demonstration data to illustrate the kinds of information available from each method. We conclude by discussing the prospects for systems-level analyses of flight control using these techniques and others like them.

  8. Ares-I-X Stability and Control Flight Test: Analysis and Plans

    Science.gov (United States)

    Brandon, Jay M.; Derry, Stephen D.; Heim, Eugene H.; Hueschen, Richard M.; Bacon, Barton J.

    2008-01-01

    The flight test of the Ares I-X vehicle provides a unique opportunity to reduce risk of the design of the Ares I vehicle and test out design, math modeling, and analysis methods. One of the key features of the Ares I design is the significant static aerodynamic instability coupled with the relatively flexible vehicle - potentially resulting in a challenging controls problem to provide adequate flight path performance while also providing adequate structural mode damping and preventing adverse control coupling to the flexible structural modes. Another challenge is to obtain enough data from the single flight to be able to conduct analysis showing the effectiveness of the controls solutions and have data to inform design decisions for Ares I. This paper will outline the modeling approaches and control system design to conduct this flight test, and also the system identification techniques developed to extract key information such as control system performance (gain/phase margins, for example), structural dynamics responses, and aerodynamic model estimations.

  9. Hydraulic lifter for an underwater drilling rig

    Energy Technology Data Exchange (ETDEWEB)

    Garan' ko, Yu L

    1981-01-15

    A hydraulic lifter is suggested for an underwater drilling rig. It includes a base, hydraulic cylinders for lifting the drilling pipes connected to the clamp holder and hydraulic distributor. In order to simplify the design of the device, the base is made with a hollow chamber connected to the rod cavities and through the hydraulic distributor to the cavities of the hydraulic cylinders for lifting the drilling pipes. The hydraulic distributor is connected to the hydrosphere through the supply valve with control in time or by remote control. The base is equipped with reverse valves whose outlets are on the support surface of the base.

  10. Dynamic modeling and ascent flight control of Ares-I Crew Launch Vehicle

    Science.gov (United States)

    Du, Wei

    This research focuses on dynamic modeling and ascent flight control of large flexible launch vehicles such as the Ares-I Crew Launch Vehicle (CLV). A complete set of six-degrees-of-freedom dynamic models of the Ares-I, incorporating its propulsion, aerodynamics, guidance and control, and structural flexibility, is developed. NASA's Ares-I reference model and the SAVANT Simulink-based program are utilized to develop a Matlab-based simulation and linearization tool for an independent validation of the performance and stability of the ascent flight control system of large flexible launch vehicles. A linearized state-space model as well as a non-minimum-phase transfer function model (which is typical for flexible vehicles with non-collocated actuators and sensors) are validated for ascent flight control design and analysis. This research also investigates fundamental principles of flight control analysis and design for launch vehicles, in particular the classical "drift-minimum" and "load-minimum" control principles. It is shown that an additional feedback of angle-of-attack can significantly improve overall performance and stability, especially in the presence of unexpected large wind disturbances. For a typical "non-collocated actuator and sensor" control problem for large flexible launch vehicles, non-minimum-phase filtering of "unstably interacting" bending modes is also shown to be effective. The uncertainty model of a flexible launch vehicle is derived. The robust stability of an ascent flight control system design, which directly controls the inertial attitude-error quaternion and also employs the non-minimum-phase filters, is verified by the framework of structured singular value (mu) analysis. Furthermore, nonlinear coupled dynamic simulation results are presented for a reference model of the Ares-I CLV as another validation of the feasibility of the ascent flight control system design. Another important issue for a single main engine launch vehicle is

  11. Simulation and Optimization of Control of Selected Phases of Gyroplane Flight

    Directory of Open Access Journals (Sweden)

    Wienczyslaw Stalewski

    2018-02-01

    Full Text Available Optimization methods are increasingly used to solve problems in aeronautical engineering. Typically, optimization methods are utilized in the design of an aircraft airframe or its structure. The presented study is focused on improvement of aircraft flight control procedures through numerical optimization. The optimization problems concern selected phases of flight of a light gyroplane—a rotorcraft using an unpowered rotor in autorotation to develop lift and an engine-powered propeller to provide thrust. An original methodology of computational simulation of rotorcraft flight was developed and implemented. In this approach the aircraft motion equations are solved step-by-step, simultaneously with the solution of the Unsteady Reynolds-Averaged Navier–Stokes equations, which is conducted to assess aerodynamic forces acting on the aircraft. As a numerical optimization method, the BFGS (Broyden–Fletcher–Goldfarb–Shanno algorithm was adapted. The developed methodology was applied to optimize the flight control procedures in selected stages of gyroplane flight in direct proximity to the ground, where proper control of the aircraft is critical to ensure flight safety and performance. The results of conducted computational optimizations proved the qualitative correctness of the developed methodology. The research results can be helpful in the design of easy-to-control gyroplanes and also in the training of pilots for this type of rotorcraft.

  12. Behavioural system identification of visual flight speed control in Drosophila melanogaster.

    Science.gov (United States)

    Rohrseitz, Nicola; Fry, Steven N

    2011-02-06

    Behavioural control in many animals involves complex mechanisms with intricate sensory-motor feedback loops. Modelling allows functional aspects to be captured without relying on a description of the underlying complex, and often unknown, mechanisms. A wide range of engineering techniques are available for modelling, but their ability to describe time-continuous processes is rarely exploited to describe sensory-motor control mechanisms in biological systems. We performed a system identification of visual flight speed control in the fruitfly Drosophila, based on an extensive dataset of open-loop responses previously measured under free flight conditions. We identified a second-order under-damped control model with just six free parameters that well describes both the transient and steady-state characteristics of the open-loop data. We then used the identified control model to predict flight speed responses after a visual perturbation under closed-loop conditions and validated the model with behavioural measurements performed in free-flying flies under the same closed-loop conditions. Our system identification of the fruitfly's flight speed response uncovers the high-level control strategy of a fundamental flight control reflex without depending on assumptions about the underlying physiological mechanisms. The results are relevant for future investigations of the underlying neuromotor processing mechanisms, as well as for the design of biomimetic robots, such as micro-air vehicles.

  13. Distributed Flight Controls for UAVs, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Two novel flight control actuation concepts for UAV applications are proposed for research and development, both of which incorporate shape memory alloy (SMA) wires...

  14. Hydraulically actuated hexapod robots design, implementation and control

    CERN Document Server

    Nonami, Kenzo; Irawan, Addie; Daud, Mohd Razali

    2014-01-01

    Legged robots are a promising locomotion system, capable of performing tasks that conventional vehicles cannot. Even more exciting is the fact that this is a rapidly developing field of study for researchers from a variety of disciplines. However, only a few books have been published on the subject of multi-legged robots. The main objective of this book is to describe some of the major control issues concerning walking robots that the authors have faced over the past 10 years. A second objective is to focus especially on very large hydraulically driven hexapod robot locomotion weighing more than 2,000 kg, making this the first specialized book on this topic. The 10 chapters of the book touch on diverse relevant topics such as design aspects, implementation issues, modeling for control, navigation and control, force and impedance control-based walking, fully autonomous walking, walking and working tasks of hexapod robots, and the future of walking robots. The construction machines of the future will very likel...

  15. Orion Exploration Flight Test Reaction Control System Jet Interaction Heating Environment from Flight Data

    Science.gov (United States)

    White, Molly E.; Hyatt, Andrew J.

    2016-01-01

    The Orion Multi-Purpose Crew Vehicle (MPCV) Reaction Control System (RCS) is critical to guide the vehicle along the desired trajectory during re-­-entry. However, this system has a significant impact on the convective heating environment to the spacecraft. Heating augmentation from the jet interaction (JI) drives thermal protection system (TPS) material selection and thickness requirements for the spacecraft. This paper describes the heating environment from the RCS on the afterbody of the Orion MPCV during Orion's first flight test, Exploration Flight Test 1 (EFT-1). These jet plumes interact with the wake of the crew capsule and cause an increase in the convective heating environment. Not only is there widespread influence from the jet banks, there may also be very localized effects. The firing history during EFT-1 will be summarized to assess which jet bank interaction was measured during flight. Heating augmentation factors derived from the reconstructed flight data will be presented. Furthermore, flight instrumentation across the afterbody provides the highest spatial resolution of the region of influence of the individual jet banks of any spacecraft yet flown. This distribution of heating augmentation across the afterbody will be derived from the flight data. Additionally, trends with possible correlating parameters will be investigated to assist future designs and ground testing programs. Finally, the challenges of measuring JI, applying this data to future flights and lessons learned will be discussed.

  16. Tap Water Hydraulic Control Systems - Design and Industrial Applications. Chapter 7 in Advances in Hydraulic Control Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    Deals with development and design of modern tap water hydraulic components and systems, in particalar the Danfoss Nessie-family of components and systems working with pure tap water without any kind of additives. Typical industrial applications are presented and the perspectives of new industrial...... applications and the environmental benefits are in focus, in particular in the food processing industry and in fire-fighting systems.......Deals with development and design of modern tap water hydraulic components and systems, in particalar the Danfoss Nessie-family of components and systems working with pure tap water without any kind of additives. Typical industrial applications are presented and the perspectives of new industrial...

  17. Flight Test of an L(sub 1) Adaptive Controller on the NASA AirSTAR Flight Test Vehicle

    Science.gov (United States)

    Gregory, Irene M.; Xargay, Enric; Cao, Chengyu; Hovakimyan, Naira

    2010-01-01

    This paper presents results of a flight test of the L-1 adaptive control architecture designed to directly compensate for significant uncertain cross-coupling in nonlinear systems. The flight test was conducted on the subscale turbine powered Generic Transport Model that is an integral part of the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. The results presented are for piloted tasks performed during the flight test.

  18. Qualitative Functional Decomposition Analysis of Evolved Neuromorphic Flight Controllers

    Directory of Open Access Journals (Sweden)

    Sanjay K. Boddhu

    2012-01-01

    Full Text Available In the previous work, it was demonstrated that one can effectively employ CTRNN-EH (a neuromorphic variant of EH method methodology to evolve neuromorphic flight controllers for a flapping wing robot. This paper describes a novel frequency grouping-based analysis technique, developed to qualitatively decompose the evolved controllers into explainable functional control blocks. A summary of the previous work related to evolving flight controllers for two categories of the controller types, called autonomous and nonautonomous controllers, is provided, and the applicability of the newly developed decomposition analysis for both controller categories is demonstrated. Further, the paper concludes with appropriate discussion of ongoing work and implications for possible future work related to employing the CTRNN-EH methodology and the decomposition analysis techniques presented in this paper.

  19. Digital switched hydraulics

    Science.gov (United States)

    Pan, Min; Plummer, Andrew

    2018-06-01

    This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems (SIHSs). The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.

  20. An Integrated Approach to Aircraft Modelling and Flight Control Law Design

    NARCIS (Netherlands)

    Looye, G.H.N.

    2008-01-01

    The design of flight control laws (FCLs) for automatic and manual (augmented) control of aircraft is a complicated task. FCLs have to fulfil large amounts of performance criteria and must work reliably in all flight conditions, for all aircraft configurations, and in adverse weather conditions.

  1. Total aircraft flight-control system - Balanced open- and closed-loop control with dynamic trim maps

    Science.gov (United States)

    Smith, G. A.; Meyer, G.

    1979-01-01

    The availability of the airborne digital computer has made possible a Total Aircraft Flight Control System (TAFCOS) that uses virtually the complete nonlinear propulsive and aerodynamic data for the aircraft to construct dynamic trim maps that represent an inversion of the aircraft model. The trim maps, in series with the aircraft, provide essentially a linear feed-forward path. Basically, open-loop trajectory control is employed with only a small perturbation feedback signal required to compensate for inaccuracy in the aircraft model and for external disturbances. Simulation results for application to an automatic carrier-landing system are presented. Flight-test results for a STOL aircraft operating automatically over a major portion of its flight regime are presented. The concept promises a more rapid and straightforward design from aerodynamic principles, particularly for highly nonlinear configurations, and requires substantially less digital computer capacity than conventional automatic flight-control system designs.

  2. An Electronic Workshop on the Performance Seeking Control and Propulsion Controlled Aircraft Results of the F-15 Highly Integrated Digital Electronic Control Flight Research Program

    Science.gov (United States)

    Powers, Sheryll Goecke (Compiler)

    1995-01-01

    Flight research for the F-15 HIDEC (Highly Integrated Digital Electronic Control) program was completed at NASA Dryden Flight Research Center in the fall of 1993. The flight research conducted during the last two years of the HIDEC program included two principal experiments: (1) performance seeking control (PSC), an adaptive, real-time, on-board optimization of engine, inlet, and horizontal tail position on the F-15; and (2) propulsion controlled aircraft (PCA), an augmented flight control system developed for landings as well as up-and-away flight that used only engine thrust (flight controls locked) for flight control. In September 1994, the background details and results of the PSC and PCA experiments were presented in an electronic workshop, accessible through the Dryden World Wide Web (http://www.dfrc.nasa.gov/dryden.html) and as a compact disk.

  3. Implementasi Prototype Alat Uji Flight Control Actuator Pesawat Berbasis Mikrokontroller Arduino Uno

    Directory of Open Access Journals (Sweden)

    NANDANG TARYANA

    2017-07-01

    Full Text Available ABSTRAKFlight control system merupakan suatu sistem di pesawat udara yang digunakan untuk manuver dari satu kondisi terbang ke kondisi terbang lainnya. Alat uji flight control actuator pesawat ini dirancang berupa prototype yang dikendalikan dengan menggunakan mikrokontroller arduino uno, yang terdiri dari input dan output. Input tersebut adalah sensor load cell yang berfungsi untuk mengetahui beban yang diterima dari aktuator pesawat, serta input sensor ping berfungsi untuk mengetahui jarak ataupun sudut dari pergerakan aktuator pesawat. Sedangkan output yang dihasilkan berupa data dari hasil pembacaan sensor load cell dan sensor ping. Alat uji flight control sistem aktuator pesawat yang telah direalisasikan mampu menggerakkan 2 buah double acting cylinder untuk bekerja naik dan turun secara bergantian serta mampu menggerakkan motor servo dengan jarak pergerakkan 3 cm – 4 cm.Kata kunci: Flight control system, Arduino Uno, double acting cylinder, Sensor Ping, Load Cell, Motor ServoABSTRACTFlight control system is a system in which aircraft are used to maneuver from one condition to fly to other flight conditions. Testing instruments aircraft flight control actuator designed a prototype of which is controlled by using microcontroller arduino uno, which consists of input and output. The input is a load cell sensor that serves to determine the load received from aircraft actuators, as well as ping sensor input is used to determine the distance or angle of the aircraft actuator movement . While the output of the data from the load cell sensor readings and sensor ping . Test equipment aircraft flight control actuator system that has been realized is able to move two pieces of double acting cylinder to work up and down alternately and able to drive the servo motor with the movement distance of 3 cm – 4 cm . Keywords: Flight control system , Arduino Uno , double acting cylinder , Ping Sensor, Load Cell, Servo Motor 

  4. A new ball launching system with controlled flight parameters for catching experiments.

    Science.gov (United States)

    d'Avella, A; Cesqui, B; Portone, A; Lacquaniti, F

    2011-03-30

    Systematic investigations of sensorimotor control of interceptive actions in naturalistic conditions, such as catching or hitting a ball moving in three-dimensional space, requires precise control of the projectile flight parameters and of the associated visual stimuli. Such control is challenging when air drag cannot be neglected because the mapping of launch parameters into flight parameters cannot be computed analytically. We designed, calibrated, and experimentally validated an actuated launching apparatus that can control the average spatial position and flight duration of a ball at a given distance from a fixed launch location. The apparatus was constructed by mounting a ball launching machine with adjustable delivery speed on an actuated structure capable of changing the spatial orientation of the launch axis while projecting balls through a hole in a screen hiding the apparatus. The calibration procedure relied on tracking the balls with a motion capture system and on approximating the mapping of launch parameters into flight parameters by means of polynomials functions. Polynomials were also used to estimate the variability of the flight parameters. The coefficients of these polynomials were obtained using the launch and flight parameters of 660 launches with 65 different initial conditions. The relative accuracy and precision of the apparatus were larger than 98% for flight times and larger than 96% for ball heights at a distance of 6m from the screen. Such novel apparatus, by reliably and automatically controlling desired ball flight characteristics without neglecting air drag, allows for a systematic investigation of naturalistic interceptive tasks. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Investigation of Inner Loop Flight Control Strategies for High-Speed Research

    Science.gov (United States)

    Newman, Brett; Kassem, Ayman

    1999-01-01

    This report describes the activities and findings conducted under contract NAS1-19858 with NASA Langley Research Center. Subject matter is the investigation of suitable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Techniques considered in this body of work are primarily conventional-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include 1) current aeroelastic vehicle modeling procedures require further emphasis and refinement, 2) traditional and nontraditional inner loop flight control strategies employing a single feedback loop do not appear sufficient for highly flexible HSCT class vehicles, 3) inner loop flight control systems will, in all likelihood, require multiple interacting feedback loops, and 4) Ref. H HSCT configuration presents major challenges to designing acceptable closed-loop flight dynamics.

  6. 75 FR 59326 - Eighth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2010-09-27

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The... Special Committee 220: Automatic Flight Guidance and Control meeting. The agenda will include: Welcome...

  7. Flight Results of the NF-15B Intelligent Flight Control System (IFCS) Aircraft with Adaptation to a Longitudinally Destabilized Plant

    Science.gov (United States)

    Bosworth, John T.

    2008-01-01

    Adaptive flight control systems have the potential to be resilient to extreme changes in airplane behavior. Extreme changes could be a result of a system failure or of damage to the airplane. The goal for the adaptive system is to provide an increase in survivability in the event that these extreme changes occur. A direct adaptive neural-network-based flight control system was developed for the National Aeronautics and Space Administration NF-15B Intelligent Flight Control System airplane. The adaptive element was incorporated into a dynamic inversion controller with explicit reference model-following. As a test the system was subjected to an abrupt change in plant stability simulating a destabilizing failure. Flight evaluations were performed with and without neural network adaptation. The results of these flight tests are presented. Comparison with simulation predictions and analysis of the performance of the adaptation system are discussed. The performance of the adaptation system is assessed in terms of its ability to stabilize the vehicle and reestablish good onboard reference model-following. Flight evaluation with the simulated destabilizing failure and adaptation engaged showed improvement in the vehicle stability margins. The convergent properties of this initial system warrant additional improvement since continued maneuvering caused continued adaptation change. Compared to the non-adaptive system the adaptive system provided better closed-loop behavior with improved matching of the onboard reference model. A detailed discussion of the flight results is presented.

  8. Stable Hovering Flight for a Small Unmanned Helicopter Using Fuzzy Control

    Directory of Open Access Journals (Sweden)

    Arbab Nighat Khizer

    2014-01-01

    Full Text Available Stable hover flight control for small unmanned helicopter under light air turbulent environment is presented. Intelligent fuzzy logic is chosen because it is a nonlinear control technique based on expert knowledge and is capable of handling sensor created noise and contradictory inputs commonly encountered in flight control. The fuzzy nonlinear control utilizes these distinct qualities for attitude, height, and position control. These multiple controls are developed using two-loop control structure by first designing an inner-loop controller for attitude angles and height and then by establishing outer-loop controller for helicopter position. The nonlinear small unmanned helicopter model used comes from X-Plane simulator. A simulation platform consisting of MATLAB/Simulink and X-Plane© flight simulator was introduced to implement the proposed controls. The main objective of this research is to design computationally intelligent control laws for hovering and to test and analyze this autopilot for small unmanned helicopter model on X-Plane under ideal and mild turbulent condition. Proposed fuzzy flight controls are validated using an X-Plane helicopter model before being embedded on actual helicopter. To show the effectiveness of the proposed fuzzy control method and its ability to cope with the external uncertainties, results are compared with a classical PD controller. Simulated results show that two-loop fuzzy controllers have a good ability to establish stable hovering for a class of unmanned rotorcraft in the presence of light turbulent environment.

  9. Pseudo Control Hedging and its Application for Safe Flight Envelope Protection

    NARCIS (Netherlands)

    Lombaerts, T.J.J.; Looye, G.H.N.; Chu, Q.P.; Mulder, J.A.

    2010-01-01

    This paper describes how the previously developed concept of Pseudo Control Hedging (PCH) can be integrated in a Fault Tolerant Flight Controller (FTFC) as a safe flight envelope protection system of the first degree. This PCH algorithm adapts the reference model for the system output in case of

  10. 76 FR 22163 - Tenth Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2011-04-20

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220 meeting: Automatic Flight Guidance and Control. SUMMARY: The FAA is... hereby given for a Special Committee 220, Automatic Flight Guidance and Control. Agenda Tuesday May 10...

  11. 76 FR 38742 - Eleventh Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2011-07-01

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220 Meeting: Automatic Flight Guidance and Control. SUMMARY: The..., Automatic Flight Guidance and Control. Agenda Tuesday August 9-Thursday, August 11, 2011 Tuesday, August 9...

  12. 75 FR 15770 - Sixth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2010-03-30

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The FAA is... hereby given for a Special Committee 220: Automatic Flight Guidance and Control meeting. The agenda will...

  13. 75 FR 80886 - Ninth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2010-12-23

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The FAA is... for a Special Committee 220: Automatic Flight Guidance and Control meeting. The agenda will include...

  14. F-15 Intelligent Flight Control System and Aeronautics Research at NASA Dryden

    Science.gov (United States)

    Brown, Nelson A.

    2009-01-01

    This viewgraph presentation reviews the F-15 Intelligent Flight Control System and Aeronautics including Autonomous Aerial Refueling Demonstrations, X-48B Blended Wing Body, F-15 Quiet Spike, and NF-15 Intelligent Flight Controls.

  15. Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations Using a Piloted Aircraft

    Science.gov (United States)

    Hanson, Curt

    2014-01-01

    An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority.

  16. User type certification for advanced flight control systems

    Science.gov (United States)

    Gilson, Richard D.; Abbott, David W.

    1994-01-01

    Advanced avionics through flight management systems (FMS) coupled with autopilots can now precisely control aircraft from takeoff to landing. Clearly, this has been the most important improvement in aircraft since the jet engine. Regardless of the eventual capabilities of this technology, it is doubtful that society will soon accept pilotless airliners with the same aplomb they accept driverless passenger trains. Flight crews are still needed to deal with inputing clearances, taxiing, in-flight rerouting, unexpected weather decisions, and emergencies; yet it is well known that the contribution of human errors far exceed those of current hardware or software systems. Thus human errors remain, and are even increasing in percentage as the largest contributor to total system error. Currently, the flight crew is regulated by a layered system of certification: by operation, e.g., airline transport pilot versus private pilot; by category, e.g., airplane versus helicopter; by class, e.g., single engine land versus multi-engine land; and by type (for larger aircraft and jet powered aircraft), e.g., Boeing 767 or Airbus A320. Nothing in the certification process now requires an in-depth proficiency with specific types of avionics systems despite their prominent role in aircraft control and guidance.

  17. A pilot rating scale for evaluating failure transients in electronic flight control systems

    Science.gov (United States)

    Hindson, William S.; Schroeder, Jeffery A.; Eshow, Michelle M.

    1990-01-01

    A pilot rating scale was developed to describe the effects of transients in helicopter flight-control systems on safety-of-flight and on pilot recovery action. The scale was applied to the evaluation of hardovers that could potentially occur in the digital flight-control system being designed for a variable-stability UH-60A research helicopter. Tests were conducted in a large moving-base simulator and in flight. The results of the investigation were combined with existing airworthiness criteria to determine quantitative reliability design goals for the control system.

  18. Robust Predictive Functional Control for Flight Vehicles Based on Nonlinear Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Yinhui Zhang

    2015-01-01

    Full Text Available A novel robust predictive functional control based on nonlinear disturbance observer is investigated in order to address the control system design for flight vehicles with significant uncertainties, external disturbances, and measurement noise. Firstly, the nonlinear longitudinal dynamics of the flight vehicle are transformed into linear-like state-space equations with state-dependent coefficient matrices. And then the lumped disturbances are considered in the linear structure predictive model of the predictive functional control to increase the precision of the predictive output and resolve the intractable mismatched disturbance problem. As the lumped disturbances cannot be derived or measured directly, the nonlinear disturbance observer is applied to estimate the lumped disturbances, which are then introduced to the predictive functional control to replace the unknown actual lumped disturbances. Consequently, the robust predictive functional control for the flight vehicle is proposed. Compared with the existing designs, the effectiveness and robustness of the proposed flight control are illustrated and validated in various simulation conditions.

  19. The X-43A Hyper-X Mach 7 Flight 2 Guidance, Navigation, and Control Overview and Flight Test Results

    Science.gov (United States)

    Bahm, Catherine; Baumann, Ethan; Martin, John; Bose, David; Beck, Roger E.; Strovers, Brian

    2005-01-01

    The objective of the Hyper-X program was to flight demonstrate an airframe-integrated hypersonic vehicle. On March 27, 2004, the Hyper-X program team successfully conducted flight 2 and achieved all of the research objectives. The Hyper-X research vehicle successfully separated from the Hyper-X launch vehicle and achieved the desired engine test conditions before the experiment began. The research vehicle rejected the disturbances caused by the cowl door opening and the fuel turning on and off and maintained the engine test conditions throughout the experiment. After the engine test was complete, the vehicle recovered and descended along a trajectory while performing research maneuvers. The last data acquired showed that the vehicle maintained control to the water. This report will provide an overview of the research vehicle guidance and control systems and the performance of the vehicle during the separation event and engine test. The research maneuvers were performed to collect data for aerodynamics and flight controls research. This report also will provide an overview of the flight controls related research and results.

  20. State of Art of the CAREM-25 Hydraulic Control Rod Drives Feasibility Analysis

    International Nuclear Information System (INIS)

    Mazufri, C.M; Mazzi, R.O

    2000-01-01

    The proposed design adopted for the control rod drives for the CAREM reactor is based on a hydraulic system.As any innovative device, the design process requires to obtain experimental evidence to identify the most important control parameters and to set their relationship with other design parameters, in order to guarantee its feasibility as a previous step to the design qualification tests at the working conditions at the reactor.This paper features a global evaluation of the analysis performed and experimental results obtained in a low pressure loop, design improvements, limiting phenomena identified and corrective actions analyzed or proposed.The evaluation is based on a repetitivity, sensitivity and scalability study of the control parameters and test conditions, as well as the dynamic response between rod drive and the hydraulic system and features related with the mechanical design.Obtained results show that present system has an adequate response compatible with functional and manufacturing requirements

  1. Elevator and hydraulics; Elevator to yuatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, I. [Hitachi, Ltd., Tokyo (Japan)

    1994-07-15

    A hydraulic type elevator is installed in relatively lower buildings as compared with a rope type elevator, but the ratio in the number of installation of the former elevator is increasing. This paper explains from its construction and features to especially various control systems for the riding comfort and safety. A direct push-up system with hydraulic jacks arranged beneath a car, and an indirect push-up system that has hydraulic jacks arranged on flank of a car and transmits the movement of a plunger via a rope are available. The latter system eliminates the need of large holes to embed hydraulic jacks. While the speed is controlled by controlling flow rates of high-pressure oil, the speed, position, acceleration and even time differential calculus of the acceleration must be controlled severely. The system uses two-step control for the through-speed and the landing speed. Different systems that have been realized may include compensation for temperatures in flow rate control valves, load pressures, and oil viscosity, from learning control to fuzzy control for psychological effects, or control of inverters in motors. 13 refs., 12 figs., 1 tab.

  2. Adaptive Backstepping Flight Control for Modern Fighter Aircraft

    NARCIS (Netherlands)

    Sonneveldt, L.

    2010-01-01

    The main goal of this thesis is to investigate the potential of the nonlinear adaptive backstepping control technique in combination with online model identification for the design of a reconfigurable flight control system for a modern fighter aircraft. Adaptive backstepping is a recursive,

  3. NRC Information No. 87-56: Improper hydraulic control unit installation at BWR plants

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    This information notice is being provided to alert addressees to a potential problem that could affect the ability of the hydraulic control units (HCUs) to control the positioning of the control rods in the event of an earthquake. In addition, the potential for damage to the control rod drive (CRD) system withdraw lines that exists under certain conditions could result in a small-break loss-of-coolant accident in the HCU area. The CRD system controls the position of the control rods within the reactor core either to change reactor core power or to rapidly shut down the reactor (scram). The HCU is a major component of the CRD system that incorporates all the hydraulic, electrical, and pneumatic equipment necessary to move one CRD mechanism during normal or scram operations. This equipment, which includes the accumulators, CRD insert lines, CRD withdraw lines, and scram valves, is supported by the HCU frames. If a sufficiently large number of HCU frame bolts are missing or loose, a Safe Shutdown Earthquake (SSE) could result in damage affecting the ability of the CRD system to control the positioning of the control rods. In addition, damage to a CRD withdraw line could result in a small-break loss-of-coolant accident in the area of the HCUs

  4. Hybrid Robust Control Law with Disturbance Observer for High-Frequency Response Electro-Hydraulic Servo Loading System

    Directory of Open Access Journals (Sweden)

    Zhiqing Sheng

    2016-04-01

    Full Text Available Addressing the simulating issue of the helicopter-manipulating booster aerodynamic load with high-frequency dynamic load superimposed on a large static load, this paper studies the design of the robust controller for the electro-hydraulic loading system to realize the simulation of this kind of load. Firstly, the equivalent linear model of the electro-hydraulic loading system under assumed parameter uncertainty is established. Then, a hybrid control scheme is proposed for the loading system. This control scheme consists of a constant velocity feed-forward compensator, a robust inner loop compensator based on disturbance observer and a robust outer loop feedback controller. The constant velocity compensator eliminates most of the extraneous force at first, and then the double-loop cascade composition control strategy is employed to design the compensated system. The disturbance observer–based inner loop compensator further restrains the disturbances including the remaining extraneous force, and makes the actual plant tracking a nominal model approximately in a certain frequency range. The robust outer loop controller achieves the desired force-tracking performance, and guarantees system robustness in the high frequency region. The optimized low-pass filter Q(s is designed by using the H∞ mixed sensitivity optimization method. The simulation results show that the proposed hybrid control scheme and controller can effectively suppress the extraneous force and improve the robustness of the electro-hydraulic loading system.

  5. 76 FR 50809 - Eleventh Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2011-08-16

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Correction of Notice of RTCA Special Committee 220 meeting: Automatic Flight Guidance and Control...: Automatic Flight Guidance and Control DATES: The meeting will be held September 13-15, 2011, from 9 a.m. to...

  6. Water hydraulic applications in hazardous environments

    International Nuclear Information System (INIS)

    Siuko, M.; Koskinen, K.T.; Vilenius, M.J.

    1996-01-01

    Water hydraulic technology provides several advantages for devices operating in critical environment. Though water hydraulics has traditionally been used in very rough applications, gives recent strong development of components possibility to build more sophisticated applications and devices with similar capacity and control properties than those of oil hydraulics without the disadvantages of oil hydraulic systems. In this paper, the basic principles, possibilities and advantages of water hydraulics are highlighted, some of the most important design considerations are presented and recent developments of water hydraulic technology are presented. Also one interesting application area, ITER fusion reactor remote handling devices, are discussed. (Author)

  7. Internal hydraulic control in the Little Belt, Denmark - observations of flow configurations and water mass formation

    Science.gov (United States)

    Holtegaard Nielsen, Morten; Vang, Torben; Chresten Lund-Hansen, Lars

    2017-12-01

    Internal hydraulic control, which occurs when stratified water masses are forced through an abrupt constriction, plays an enormous role in nature on both large and regional scales with respect to dynamics, circulation, and water mass formation. Despite a growing literature on this subject surprisingly few direct observations have been made that conclusively show the existence of and the circumstances related to internal hydraulic control in nature. In this study we present observations from the Little Belt, Denmark, one of three narrow straits connecting the Baltic Sea and the North Sea. The observations (comprised primarily of along-strait, detailed transects of salinity and temperature; continuous observations of flow velocity, salinity, and temperature at a permanent station; and numerous vertical profiles of salinity, temperature, fluorescence, and flow velocity in various locations) show that internal hydraulic control is a frequently occurring phenomenon in the Little Belt. The observations, which are limited to south-going flows of approximately two-layered water masses, show that internal hydraulic control may take either of two configurations, i.e. the lower or the upper layer being the active, accelerating one. This is connected to the depth of the pycnocline on the upstream side and the topography, which is both deepening and contracting toward the narrow part of the Little Belt. The existence of two possible flow configurations is known from theoretical and laboratory studies, but we believe that this has never been observed in nature and reported before. The water masses formed by the intense mixing, which is tightly connected with the presence of control, may be found far downstream of the point of control. The observations show that these particular water masses are associated with chlorophyll concentrations that are considerably higher than in adjacent water masses, showing that control has a considerable influence on the primary production and

  8. Flight Test Results from the NF-15B Intelligent Flight Control System (IFCS) Project with Adaptation to a Simulated Stabilator Failure

    Science.gov (United States)

    Bosworth, John T.; Williams-Hayes, Peggy S.

    2010-01-01

    Adaptive flight control systems have the potential to be more resilient to extreme changes in airplane behavior. Extreme changes could be a result of a system failure or of damage to the airplane. A direct adaptive neural-network-based flight control system was developed for the National Aeronautics and Space Administration NF-15B Intelligent Flight Control System airplane and subjected to an inflight simulation of a failed (frozen) (unmovable) stabilator. Formation flight handling qualities evaluations were performed with and without neural network adaptation. The results of these flight tests are presented. Comparison with simulation predictions and analysis of the performance of the adaptation system are discussed. The performance of the adaptation system is assessed in terms of its ability to decouple the roll and pitch response and reestablish good onboard model tracking. Flight evaluation with the simulated stabilator failure and adaptation engaged showed that there was generally improvement in the pitch response; however, a tendency for roll pilot-induced oscillation was experienced. A detailed discussion of the cause of the mixed results is presented.

  9. Safety of 5 MW district heating reactor (DHR) and hydraulic dynamic pressure drive control rods

    International Nuclear Information System (INIS)

    Wu Yuanqiang; Wang Dazhong

    1991-11-01

    The principles and movement characteristic of the hydraulic dynamic pressure drive for control rods in 5 MW district heating reactor are described with stress on analysis of its effects on reactor safety features. The drive is different from electric-magnetic drive for PWR or hydraulic drive for BWR. The drive cylinder is driven by dynamic pressure. In the new drive system, the reactor coolant (water) used as actuating medium is pressed by pump, then injected into a step cylinder which is set in the reactor core. The cylinder will move step by step by controlling flow, then the cylinder drives the neutron absorber and controls nuclear reaction. The drive is characterized by simplicity in structure, high reliability, inherent safety, reduction in reactor height, economy, etc

  10. Simulator Evaluation of Simplified Propulsion-Only Emergency Flight Control Systems on Transport Aircraft

    Science.gov (United States)

    Burcham, Frank W., Jr.; Kaneshige, John; Bull, John; Maine, Trindel A.

    1999-01-01

    With the advent of digital engine control systems, considering the use of engine thrust for emergency flight control has become feasible. Many incidents have occurred in which engine thrust supplemented or replaced normal aircraft flight controls. In most of these cases, a crash has resulted, and more than 1100 lives have been lost. The NASA Dryden Flight Research Center has developed a propulsion-controlled aircraft (PCA) system in which computer-controlled engine thrust provides emergency flight control capability. Using this PCA system, an F-15 and an MD-11 airplane have been landed without using any flight controls. In simulations, C-17, B-757, and B-747 PCA systems have also been evaluated successfully. These tests used full-authority digital electronic control systems on the engines. Developing simpler PCA systems that can operate without full-authority engine control, thus allowing PCA technology to be installed on less capable airplanes or at lower cost, is also a desire. Studies have examined simplified ?PCA Ultralite? concepts in which thrust control is provided using an autothrottle system supplemented by manual differential throttle control. Some of these concepts have worked well. The PCA Ultralite study results are presented for simulation tests of MD-11, B-757, C-17, and B-747 aircraft.

  11. 75 FR 36471 - Seventh Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2010-06-25

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The... Committee 220: Automatic Flight Guidance and [[Page 36472

  12. Flight control optimization from design to assessment application on the Cessna Citation X business aircraft =

    Science.gov (United States)

    Boughari, Yamina

    New methodologies have been developed to optimize the integration, testing and certification of flight control systems, an expensive process in the aerospace industry. This thesis investigates the stability of the Cessna Citation X aircraft without control, and then optimizes two different flight controllers from design to validation. The aircraft's model was obtained from the data provided by the Research Aircraft Flight Simulator (RAFS) of the Cessna Citation business aircraft. To increase the stability and control of aircraft systems, optimizations of two different flight control designs were performed: 1) the Linear Quadratic Regulation and the Proportional Integral controllers were optimized using the Differential Evolution algorithm and the level 1 handling qualities as the objective function. The results were validated for the linear and nonlinear aircraft models, and some of the clearance criteria were investigated; and 2) the Hinfinity control method was applied on the stability and control augmentation systems. To minimize the time required for flight control design and its validation, an optimization of the controllers design was performed using the Differential Evolution (DE), and the Genetic algorithms (GA). The DE algorithm proved to be more efficient than the GA. New tools for visualization of the linear validation process were also developed to reduce the time required for the flight controller assessment. Matlab software was used to validate the different optimization algorithms' results. Research platforms of the aircraft's linear and nonlinear models were developed, and compared with the results of flight tests performed on the Research Aircraft Flight Simulator. Some of the clearance criteria of the optimized H-infinity flight controller were evaluated, including its linear stability, eigenvalues, and handling qualities criteria. Nonlinear simulations of the maneuvers criteria were also investigated during this research to assess the Cessna

  13. A Survey on Open-Source Flight Control Platforms of Unmanned Aerial Vehicle

    DEFF Research Database (Denmark)

    Ebeid, Emad Samuel Malki; Skriver, Martin; Jin, Jie

    2017-01-01

    Recently, Unmanned Aerial Vehicle (UAV), so-called drones, have gotten a lot of attention in academic research and commercial applications due to their simple structure, ease of operations and low-cost hardware components. Flight controller, embedded electronics component, represents the core part...... of the drone. It aims at performing the main operations of the drone (e.g., autonomous control and navigation). There are various types of flight controllers and each of them has its own characteristics and features. This paper presents an extensive survey on the publicly available open-source flight...

  14. Using Feedback Error Learning for Control of Electro Hydraulic Servo System by Laguerre

    Directory of Open Access Journals (Sweden)

    Amir Reza Zare Bidaki

    2014-01-01

    Full Text Available In this paper, a new Laguerre controller is proposed to control the electro hydraulic servo system. The proposed controller uses feedback error learning method and leads to significantly improve performance in terms of settling time and amplitude of control signal rather than other controllers. All derived results are validated by simulation of nonlinear mathematical model of the system. The simulation results show the advantages of the proposed method for improved control in terms of both settling time and amplitude of control signal.

  15. Non Linear Modelling and Control of Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    B. Šulc

    2002-01-01

    Full Text Available This paper deals with non-linear modelling and control of a differential hydraulic actuator. The nonlinear state space equations are derived from basic physical laws. They are more powerful than the transfer function in the case of linear models, and they allow the application of an object oriented approach in simulation programs. The effects of all friction forces (static, Coulomb and viscous have been modelled, and many phenomena that are usually neglected are taken into account, e.g., the static term of friction, the leakage between the two chambers and external space. Proportional Differential (PD and Fuzzy Logic Controllers (FLC have been applied in order to make a comparison by means of simulation. Simulation is performed using Matlab/Simulink, and some of the results are compared graphically. FLC is tuned in a such way that it produces a constant control signal close to its maximum (or minimum, where possible. In the case of PD control the occurrence of peaks cannot be avoided. These peaks produce a very high velocity that oversteps the allowed values.

  16. Adaptive Augmenting Control Flight Characterization Experiment on an F/A-18

    Science.gov (United States)

    VanZwieten, Tannen S.; Orr, Jeb S.; Wall, John H.; Gilligan, Eric T.

    2014-01-01

    This paper summarizes the Adaptive Augmenting Control (AAC) flight characterization experiments performed using an F/A-18 (TN 853). AAC was designed and developed specifically for launch vehicles, and is currently part of the baseline autopilot design for NASA's Space Launch System (SLS). The scope covered here includes a brief overview of the algorithm (covered in more detail elsewhere), motivation and benefits of flight testing, top-level SLS flight test objectives, applicability of the F/A-18 as a platform for testing a launch vehicle control design, test cases designed to fully vet the AAC algorithm, flight test results, and conclusions regarding the functionality of AAC. The AAC algorithm developed at Marshall Space Flight Center is a forward loop gain multiplicative adaptive algorithm that modifies the total attitude control system gain in response to sensed model errors or undesirable parasitic mode resonances. The AAC algorithm provides the capability to improve or decrease performance by balancing attitude tracking with the mitigation of parasitic dynamics, such as control-structure interaction or servo-actuator limit cycles. In the case of the latter, if unmodeled or mismodeled parasitic dynamics are present that would otherwise result in a closed-loop instability or near instability, the adaptive controller decreases the total loop gain to reduce the interaction between these dynamics and the controller. This is in contrast to traditional adaptive control logic, which focuses on improving performance by increasing gain. The computationally simple AAC attitude control algorithm has stability properties that are reconcilable in the context of classical frequency-domain criteria (i.e., gain and phase margin). The algorithm assumes that the baseline attitude control design is well-tuned for a nominal trajectory and is designed to adapt only when necessary. Furthermore, the adaptation is attracted to the nominal design and adapts only on an as-needed basis

  17. Background and principles of throttles-only flight control

    Science.gov (United States)

    Burcham, Frank W., Jr.

    1995-01-01

    There have been many cases in which the crew of a multi-engine airplane had to use engine thrust for emergency flight control. Such a procedure is very difficult, because the propulsive control forces are small, the engine response is slow, and airplane dynamics such as the phugoid and dutch roll are difficult to damp with thrust. In general, thrust increases are used to climb, thrust decreases to descend, and differential thrust is used to turn. Average speed is not significantly affected by changes in throttle setting. Pitch control is achieved because of pitching moments due to speed changes, from thrust offset, and from the vertical component of thrust. Roll control is achieved by using differential thrust to develop yaw, which, through the normal dihedral effect, causes a roll. Control power in pitch and roll tends to increase as speed decreases. Although speed is not controlled by the throttles, configuration changes are often available (lowering gear, flaps, moving center-of-gravity) to change the speed. The airplane basic stability is also a significant factor. Fuel slosh and gyroscopic moments are small influences on throttles-only control. The background and principles of throttles-only flight control are described.

  18. NASA Marshall Space Flight Center Controls Systems Design and Analysis Branch

    Science.gov (United States)

    Gilligan, Eric

    2014-01-01

    Marshall Space Flight Center maintains a critical national capability in the analysis of launch vehicle flight dynamics and flight certification of GN&C algorithms. MSFC analysts are domain experts in the areas of flexible-body dynamics and control-structure interaction, thrust vector control, sloshing propellant dynamics, and advanced statistical methods. Marshall's modeling and simulation expertise has supported manned spaceflight for over 50 years. Marshall's unparalleled capability in launch vehicle guidance, navigation, and control technology stems from its rich heritage in developing, integrating, and testing launch vehicle GN&C systems dating to the early Mercury-Redstone and Saturn vehicles. The Marshall team is continuously developing novel methods for design, including advanced techniques for large-scale optimization and analysis.

  19. An Entry Flight Controls Analysis for a Reusable Launch Vehicle

    Science.gov (United States)

    Calhoun, Philip

    2000-01-01

    The NASA Langley Research Center has been performing studies to address the feasibility of various single-stage to orbit concepts for use by NASA and the commercial launch industry to provide a lower cost access to space. Some work on the conceptual design of a typical lifting body concept vehicle, designated VentureStar(sup TM) has been conducted in cooperation with the Lockheed Martin Skunk Works. This paper will address the results of a preliminary flight controls assessment of this vehicle concept during the atmospheric entry phase of flight. The work includes control analysis from hypersonic flight at the atmospheric entry through supersonic speeds to final approach and landing at subsonic conditions. The requirements of the flight control effectors are determined over the full range of entry vehicle Mach number conditions. The analysis was performed for a typical maximum crossrange entry trajectory utilizing angle of attack to limit entry heating and providing for energy management, and bank angle to modulation of the lift vector to provide downrange and crossrange capability to fly the vehicle to a specified landing site. Sensitivity of the vehicle open and closed loop characteristics to CG location, control surface mixing strategy and wind gusts are included in the results. An alternative control surface mixing strategy utilizing a reverse aileron technique demonstrated a significant reduction in RCS torque and fuel required to perform bank maneuvers during entry. The results of the control analysis revealed challenges for an early vehicle configuration in the areas of hypersonic pitch trim and subsonic longitudinal controllability.

  20. Implementation and flight-test of a multi-mode rotorcraft flight-control system for single-pilot use in poor visibility

    Science.gov (United States)

    Hindson, William S.

    1987-01-01

    A flight investigation was conducted to evaluate a multi-mode flight control system designed according to the most recent recommendations for handling qualities criteria for new military helicopters. The modes and capabilities that were included in the system are those considered necessary to permit divided-attention (single-pilot) lowspeed and hover operations near the ground in poor visibility conditions. Design features included mode-selection and mode-blending logic, the use of an automatic position-hold mode that employed precision measurements of aircraft position, and a hover display which permitted manually-controlled hover flight tasks in simulated instrument conditions. Pilot evaluations of the system were conducted using a multi-segment evaluation task. Pilot comments concerning the use of the system are provided, and flight-test data are presented to show system performance.

  1. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    Science.gov (United States)

    Kim, Gi-Woo; Wang, K. W.

    2009-08-01

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1\\to 2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements.

  2. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    International Nuclear Information System (INIS)

    Kim, Gi-Woo; Wang, K W

    2009-01-01

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1→2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements

  3. Design of Launch Vehicle Flight Control Systems Using Ascent Vehicle Stability Analysis Tool

    Science.gov (United States)

    Jang, Jiann-Woei; Alaniz, Abran; Hall, Robert; Bedossian, Nazareth; Hall, Charles; Jackson, Mark

    2011-01-01

    A launch vehicle represents a complicated flex-body structural environment for flight control system design. The Ascent-vehicle Stability Analysis Tool (ASAT) is developed to address the complicity in design and analysis of a launch vehicle. The design objective for the flight control system of a launch vehicle is to best follow guidance commands while robustly maintaining system stability. A constrained optimization approach takes the advantage of modern computational control techniques to simultaneously design multiple control systems in compliance with required design specs. "Tower Clearance" and "Load Relief" designs have been achieved for liftoff and max dynamic pressure flight regions, respectively, in the presence of large wind disturbances. The robustness of the flight control system designs has been verified in the frequency domain Monte Carlo analysis using ASAT.

  4. Robust H(∞) positional control of 2-DOF robotic arm driven by electro-hydraulic servo system.

    Science.gov (United States)

    Guo, Qing; Yu, Tian; Jiang, Dan

    2015-11-01

    In this paper an H∞ positional feedback controller is developed to improve the robust performance under structural and parametric uncertainty disturbance in electro-hydraulic servo system (EHSS). The robust control model is described as the linear state-space equation by upper linear fractional transformation. According to the solution of H∞ sub-optimal control problem, the robust controller is designed and simplified to lower order linear model which is easily realized in EHSS. The simulation and experimental results can validate the robustness of this proposed method. The comparison result with PI control shows that the robust controller is suitable for this EHSS under the critical condition where the desired system bandwidth is higher and the external load of the hydraulic actuator is closed to its limited capability. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Aerodynamics, sensing and control of insect-scale flapping-wing flight

    Science.gov (United States)

    Shyy, Wei; Kang, Chang-kwon; Chirarattananon, Pakpong; Ravi, Sridhar; Liu, Hao

    2016-01-01

    There are nearly a million known species of flying insects and 13 000 species of flying warm-blooded vertebrates, including mammals, birds and bats. While in flight, their wings not only move forward relative to the air, they also flap up and down, plunge and sweep, so that both lift and thrust can be generated and balanced, accommodate uncertain surrounding environment, with superior flight stability and dynamics with highly varied speeds and missions. As the size of a flyer is reduced, the wing-to-body mass ratio tends to decrease as well. Furthermore, these flyers use integrated system consisting of wings to generate aerodynamic forces, muscles to move the wings, and sensing and control systems to guide and manoeuvre. In this article, recent advances in insect-scale flapping-wing aerodynamics, flexible wing structures, unsteady flight environment, sensing, stability and control are reviewed with perspective offered. In particular, the special features of the low Reynolds number flyers associated with small sizes, thin and light structures, slow flight with comparable wind gust speeds, bioinspired fabrication of wing structures, neuron-based sensing and adaptive control are highlighted. PMID:27118897

  6. The hydraulic mechanism in the hind wing veins of Cybister japonicus Sharp (order: Coleoptera

    Directory of Open Access Journals (Sweden)

    Jiyu Sun

    2016-06-01

    Full Text Available The diving beetles (Dytiscidae, Coleoptera are families of water beetles. When they see light, they fly to the light source directly from the water. Their hind wings are thin and fragile under the protection of their elytra (forewings. When the beetle is at rest the hind wings are folded over the abdomen of the beetle and when in flight they unfold to provide the necessary aerodynamic forces. In this paper, the unfolding process of the hind wing of Cybister japonicus Sharp (order: Coleoptera was investigated. The motion characteristics of the blood in the veins of the structure system show that the veins have microfluidic control over the hydraulic mechanism of the unfolding process. A model is established, and the hind wing extending process is simulated. The blood flow and pressure changes are discussed. The driving mechanism for hydraulic control of the folding and unfolding actions of beetle hind wings is put forward. This can assist the design of new deployable micro air vehicles and bioinspired deployable systems.

  7. A Computational Model of Hydraulic Volume Displacement Drive

    Directory of Open Access Journals (Sweden)

    V. N. Pil'gunov

    2014-01-01

    Full Text Available The paper offers a computational model of industrial-purpose hydraulic drive with two hydraulic volume adjustable working chamber machines (pump and motor. Adjustable pump equipped with the pressure control unit can be run together with several adjustable hydraulic motors on the principle of three-phase hydraulic socket-outlet with high-pressure lines, drain, and drainage system. The paper considers the pressure-controlled hydrostatic transmission with hydraulic motor as an output link. It shows a possibility to create a saving hydraulic drive using a functional tie between the adjusting parameters of the pump and hydraulic motor through the pressure difference, torque, and angular rate of the hydraulic motor shaft rotation. The programmable logic controller can implement such tie. The Coulomb and viscous frictions are taken into consideration when developing a computational model of the hydraulic volume displacement drive. Discharge balance considers external and internal leakages in equivalent clearances of hydraulic machines, as well as compression loss volume caused by hydraulic fluid compressibility and deformation of pipe walls. To correct dynamic properties of hydraulic drive, the paper offers that in discharge balance are included the additional regulated external leakages in the open circuit of hydraulic drive and regulated internal leakages in the closed-loop circuit. Generalized differential equations having functional multipliers and multilinked nature have been obtained to describe the operation of hydraulic positioning and speed drive with two hydraulic volume adjustable working chamber machines. It is shown that a proposed computational model of hydraulic drive can be taken into consideration in development of LS («Load-Sensing» drives, in which the pumping pressure is tuned to the value required for the most loaded slave motor to overcome the load. Results attained can be used both in designing the industrial-purpose heavy

  8. Turbogas control unit using a hydraulic interface; Control de una unidad turbogas usando una interfase hidraulica

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Palacios, Ignacio Ramon; Castelo Cuevas, Luis [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: irrp@iie.org.mx; lcastelo@iie.org.mx; Escarcega Navarrete, Luis [Servi-Control Monterrey S.A. de C.V., Monterrey, Nuevo Leon (Mexico)]. E-mail: lescarcega@servicontrol.com

    2010-11-15

    This paper presents the design and implementation of the control system of the Turbo Generator Unit (TGU) GE 5001, placed in Laguna Chavez power generation facility in Gomez Palacio, Dgo., Mexico. This TGU had been operating with an old control system, back to the 70's. The positioning of the control valves was carried out using a complex electro-hydraulic system. For the modernization of the control system, we use latest PLC technology and a current to pressure converter to communicate the PLC with the hydraulic control valves. The new control system helped us to obtain a best response at the start and generation phases, as well as an increase in the availability of the unit. We show the old and the new control architectures besides plot results obtained at the different operation points. [Spanish] En este articulo se presenta la implementacion y diseno del sistema de control de una Unidad Turbogas (UTG) GE-5001 de la Central Turbogas Laguna Chavez de CFE ubicada en Gomez Palacio, Durango, la cual originalmente era controlada mediante un sistema de control con tecnologia de los anos 70's. El posicionamiento de las valvulas de control se realizaba mediante un sistema electro-hidraulico complejo. Para la modernizacion del sistema de control a uno con tecnologia de punta fue necesario utilizar una interfase hidraulica por medio de un convertidor de corriente/presion (I/P) para el posicionamiento de las valvulas originales. Con la modernizacion se mejoro la respuesta del control asi como el incremento de la disponibilidad de la unidad. Se presentan la arquitectura anterior y actual de sistema de control asi como graficas de los resultados obtenidos en diferentes puntos de operacion de la UTG.

  9. Intelligent Materials Used in Hydraulic, Fuel, and Rudder Control Systems of Aircrafts

    Directory of Open Access Journals (Sweden)

    D. B. Chernov

    2017-01-01

    Full Text Available The device is really intelligent, only if it is capable to respond to changing external conditions. The devices, which "feel" the external environment and can change their characteristics, have many advantages compared to the conventional devices: they are more efficient, wear out more slowly, and have lower operating costs.The scope of smart products is truly infinite. Alloys with memory effect also apply to intellectual content. Natural piezoelectric crystals such as silicon dioxide (intellectual material have been known for over a hundred years. They have greater stiffness and can be used at high operating frequencies. Due to the direct piezoelectric effect, they have been successfully used as a strain gage. Later came artificial ceramic piezoelectric materials; they are used as mechanical transducers. Thus, an inverse piezoelectric effect is usually used. It consists in the change of dimensions when an electric field is applied. Control of intellectual structure can be provided by heat fluxes, electromagnetic, hydraulic or piezoelectric forces and through application of electro-rheological, and magneto-rheological fluids. The article examines the intellectual materials and technologies that are already in place or will find its application in aviation hydraulic and fuel systems and control systems of rudders (CSR of aircrafts in the near future.The paper considers in detail the shape memory effect alloys (SMEA as "intelligent" materials. Actuators made from SMEA have a number of advantages: high working power; large recoverable deformation; different types of strain (tensile, compressive, bending and torsional; most specific value of the work per unit mass. All the SMEA advantages may be well used for the so-called thermo-mechanical connections (TMС of pipelines where SMEA drawbacks in this application, practically, do not affect the quality of TMC. In aircraft engineering the TMC were first used in hydraulic systems of the aircraft TU204

  10. Machine Learning for Flapping Wing Flight Control

    NARCIS (Netherlands)

    Goedhart, Menno; van Kampen, E.; Armanini, S.F.; de Visser, C.C.; Chu, Q.

    2018-01-01

    Flight control of Flapping Wing Micro Air Vehicles is challenging, because of their complex dynamics and variability due to manufacturing inconsistencies. Machine Learning algorithms can be used to tackle these challenges. A Policy Gradient algorithm is used to tune the gains of a

  11. 78 FR 11553 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2013-02-19

    ...; Electronic Flight Control System: Control Surface Awareness and Mode Annunciation AGENCY: Federal Aviation...) associated with the control surface awareness and mode annunciation of the electronic flight control system... a fly-by-wire electronic flight control system and no direct coupling from the flightdeck controller...

  12. 77 FR 57039 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2012-09-17

    ... Flight Control System: Control Surface Awareness and Mode Annunciation AGENCY: Federal Aviation... a fly-by-wire electronic flight control system and no direct coupling from the flightdeck controller... nuisance alerting. This special condition also addresses flight control system mode annunciation. It...

  13. Model and Sensor Based Nonlinear Adaptive Flight Control with Online System Identification

    NARCIS (Netherlands)

    Sun, L.G.

    2014-01-01

    Consensus exists that many loss-of-control (LOC) in flight accidents caused by severe aircraft damage or system failure could be prevented if flight performance could be recovered using the valid and remaining control authorities. However, the safe maneuverability of a post-failure aircraft will

  14. Performance-oriented asymptotic tracking control of hydraulic systems with radial basis function network disturbance observer

    Directory of Open Access Journals (Sweden)

    Jian Hu

    2016-05-01

    Full Text Available Uncertainties, including parametric uncertainties and uncertain nonlinearities, always exist in positioning servo systems driven by a hydraulic actuator, which would degrade their tracking accuracy. In this article, an integrated control scheme, which combines adaptive robust control together with radial basis function neural network–based disturbance observer, is proposed for high-accuracy motion control of hydraulic systems. Not only parametric uncertainties but also uncertain nonlinearities (i.e. nonlinear friction, external disturbances, and/or unmodeled dynamics are taken into consideration in the proposed controller. The above uncertainties are compensated, respectively, by adaptive control and radial basis function neural network, which are ultimately integrated together by applying feedforward compensation technique, in which the global stabilization of the controller is ensured via a robust feedback path. A new kind of parameter and weight adaptation law is designed on the basis of Lyapunov stability theory. Furthermore, the proposed controller obtains an expected steady performance even if modeling uncertainties exist, and extensive simulation results in various working conditions have proven the high performance of the proposed control scheme.

  15. An application of artificial intelligence theory to reconfigurable flight control

    Science.gov (United States)

    Handelman, David A.

    1987-01-01

    Artificial intelligence techniques were used along with statistical hpyothesis testing and modern control theory, to help the pilot cope with the issues of information, knowledge, and capability in the event of a failure. An intelligent flight control system is being developed which utilizes knowledge of cause and effect relationships between all aircraft components. It will screen the information available to the pilots, supplement his knowledge, and most importantly, utilize the remaining flight capability of the aircraft following a failure. The list of failure types the control system will accommodate includes sensor failures, actuator failures, and structural failures.

  16. Permeability, storage and hydraulic diffusivity controlled by earthquakes

    Science.gov (United States)

    Brodsky, E. E.; Fulton, P. M.; Xue, L.

    2016-12-01

    Earthquakes can increase permeability in fractured rocks. In the farfield, such permeability increases are attributed to seismic waves and can last for months after the initial earthquake. Laboratory studies suggest that unclogging of fractures by the transient flow driven by seismic waves is a viable mechanism. These dynamic permeability increases may contribute to permeability enhancement in the seismic clouds accompanying hydraulic fracking. Permeability enhancement by seismic waves could potentially be engineered and the experiments suggest the process will be most effective at a preferred frequency. We have recently observed similar processes inside active fault zones after major earthquakes. A borehole observatory in the fault that generated the M9.0 2011 Tohoku earthquake reveals a sequence of temperature pulses during the secondary aftershock sequence of an M7.3 aftershock. The pulses are attributed to fluid advection by a flow through a zone of transiently increased permeability. Directly after the M7.3 earthquake, the newly damaged fault zone is highly susceptible to further permeability enhancement, but ultimately heals within a month and becomes no longer as sensitive. The observation suggests that the newly damaged fault zone is more prone to fluid pulsing than would be expected based on the long-term permeability structure. Even longer term healing is seen inside the fault zone of the 2008 M7.9 Wenchuan earthquake. The competition between damage and healing (or clogging and unclogging) results in dynamically controlled permeability, storage and hydraulic diffusivity. Recent measurements of in situ fault zone architecture at the 1-10 meter scale suggest that active fault zones often have hydraulic diffusivities near 10-2 m2/s. This uniformity is true even within the damage zone of the San Andreas fault where permeability and storage increases balance each other to achieve this value of diffusivity over a 400 m wide region. We speculate that fault zones

  17. 75 FR 3959 - Fifth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2010-01-25

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 220: Automatic Flight...

  18. Nonlinear force feedback control of piezoelectric-hydraulic pump actuator for automotive transmission shift control

    Science.gov (United States)

    Kim, Gi-Woo; Wang, K. W.

    2008-03-01

    In recent years, researchers have investigated the feasibility of utilizing piezoelectric-hydraulic pump based actuation systems for automotive transmission controls. This new concept could eventually reduce the complexity, weight, and fuel consumption of the current transmissions. In this research, we focus on how to utilize this new approach on the shift control of automatic transmissions (AT), which generally requires pressure profiling for friction elements during the operation. To illustrate the concept, we will consider the 1--> 2 up shift control using band brake friction elements. In order to perform the actuation force tracking for AT shift control, nonlinear force feedback control laws are designed based on the sliding mode theory for the given nonlinear system. This paper will describe the modeling of the band brake actuation system, the design of the nonlinear force feedback controller, and simulation and experimental results for demonstration of the new concept.

  19. Launch vehicle flight control augmentation using smart materials and advanced composites (CDDF Project 93-05)

    Science.gov (United States)

    Barret, C.

    1995-01-01

    The Marshall Space Flight Center has a rich heritage of launch vehicles that have used aerodynamic surfaces for flight stability such as the Saturn vehicles and flight control such as on the Redstone. Recently, due to aft center-of-gravity locations on launch vehicles currently being studied, the need has arisen for the vehicle control augmentation that is provided by these flight controls. Aerodynamic flight control can also reduce engine gimbaling requirements, provide actuator failure protection, enhance crew safety, and increase vehicle reliability, and payload capability. In the Saturn era, NASA went to the Moon with 300 sq ft of aerodynamic surfaces on the Saturn V. Since those days, the wealth of smart materials and advanced composites that have been developed allow for the design of very lightweight, strong, and innovative launch vehicle flight control surfaces. This paper presents an overview of the advanced composites and smart materials that are directly applicable to launch vehicle control surfaces.

  20. Self-Guided Multimedia Stress Management and Resilience Training for Flight Controllers

    Science.gov (United States)

    Rose, R. D.; Zbozinek, T. D.; Hentschel, P. G.; Smith, S, M.; O'Brien J.; Oftedal, A.; Craske, M. G.

    2016-01-01

    Stress and anxiety-related problems are among the most common and costly behavioral health problems in society, and for those working in operational environments (i.e. astronauts, flight controllers, military) this can seriously impact crew performance, safety, and wellbeing. Technology-based interventions are effective for treating behavioral health problems, and can significantly improve the delivery of evidence-based health care. This study is evaluating the effectiveness, usefulness, and usability of a self-guided multimedia stress management and resilience training program in a randomized controlled trial (RCT) with a sample of flight controllers at Johnson Space Center. The intervention, SMART-OP (Stress Management and Resilience Training for Optimal Performance), is a six-session, cognitive behavioral-based computer program that uses self-guided, interactive activities to teach skills that can help individuals build resilience and manage stress. In a prior RCT with a sample of stressed but otherwise healthy individuals, SMART-OP reduced perceived stress and increased perceived control over stress in comparison to an Attention Control (AC) group. SMART-OP was rated as "highly useful" and "excellent" in usability and acceptability. Based on a-amylase data, individuals in SMART-OP recovered quicker and more completely from a social stress test as compared to the AC group [1]. In the current study, flight controllers are randomized either to receive SMART-OP training, or to a 6-week waitlist control period (WLC) before beginning SMART-OP. Eligible participants include JSC flight controllers and instructors without any medical or psychiatric disorder, but who are stressed based on self-report. Flight controllers provide a valid analog sample to astronauts in that they work in an operational setting, use similar terminology to astronauts, are mission-focused, and work under the same broader work culture. The study began in December 2014, and to date 79 flight

  1. Flight Research into Simple Adaptive Control on the NASA FAST Aircraft

    Science.gov (United States)

    Hanson, Curtis E.

    2011-01-01

    A series of simple adaptive controllers with varying levels of complexity were designed, implemented and flight tested on the NASA Full-Scale Advanced Systems Testbed (FAST) aircraft. Lessons learned from the development and flight testing are presented.

  2. Hydraulic High Pressure Valve Controller Using the In-Situ Pressure Difference

    Science.gov (United States)

    Bao, Xiaoqi (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor); Hall, Jeffery L. (Inventor)

    2016-01-01

    A hydraulic valve controller that uses an existing pressure differential as some or all of the power source for valve operation. In a high pressure environment, such as downhole in an oil or gas well, the pressure differential between the inside of a pipe and the outside of the pipe may be adequately large to drive a linear slide valve. The valve is operated hydraulically by a piston in a bore. When a higher pressure is applied to one end of the bore and a lower pressure to the other end, the piston moves in response to the pressure differential and drives a valve attached to it. If the pressure differential is too small to drive the piston at a sufficiently high speed, a pump is provided to generate a larger pressure differential to be applied. The apparatus is conveniently constructed using multiport valves, which can be rotary valves.

  3. A study on reliability of electro-hydraulic governor control system for large steam turbine in power plant

    International Nuclear Information System (INIS)

    Kang, Gu Hwa; Lee, Tae Hoon; Moon, Seung Jae; Lee, Jae Heon; Yoo, Ho Seon

    2008-01-01

    In this work, the right management procedure for hydraulic power oil will be discussed and suggested. A thermal power plant turbine should respond to the change of load status. However, to satisfy the frequency of alternating current, the revolution per minute should be kept constant. Therefore, by controlling the flow rate of the steam to the turbine, the governor satisfies the load variation without alternating the revolution per minutes of the turbine. To protect the governor, the hydraulic power unit should be managed carefully by controlling the quality and the flow rate of the oil

  4. Jet Engines - The New Masters of Advanced Flight Control

    Science.gov (United States)

    Gal-Or, Benjamin

    2018-05-01

    ANTICIPATED UNITED STATES CONGRESS ACT should lead to reversing a neglected duty to the people by supporting FAA induced bill to civilize classified military air combat technology to maximize flight safety of airliners and cargo jet transports, in addition to FAA certifying pilots to master Jet-Engine Steering ("JES") as automatic or pilot recovery when Traditional Aerodynamic-only Flight Control ("TAFC") fails to prevent a crash and other related damages

  5. Piloted simulation tests of propulsion control as backup to loss of primary flight controls for a mid-size jet transport

    Science.gov (United States)

    Bull, John; Mah, Robert; Davis, Gloria; Conley, Joe; Hardy, Gordon; Gibson, Jim; Blake, Matthew; Bryant, Don; Williams, Diane

    1995-01-01

    Failures of aircraft primary flight-control systems to aircraft during flight have led to catastrophic accidents with subsequent loss of lives (e.g. , DC-1O crash, B-747 crash, C-5 crash, B-52 crash, and others). Dryden Flight Research Center (DFRC) investigated the use of engine thrust for emergency flight control of several airplanes, including the B-720, Lear 24, F-15, C-402, and B-747. A series of three piloted simulation tests have been conducted at Ames Research Center to investigate propulsion control for safely landing a medium size jet transport which has experienced a total primary flight-control failure. The first series of tests was completed in July 1992 and defined the best interface for the pilot commands to drive the engines. The second series of tests was completed in August 1994 and investigated propulsion controlled aircraft (PCA) display requirements and various command modes. The third series of tests was completed in May 1995 and investigated PCA full-flight envelope capabilities. This report describes the concept of a PCA, discusses pilot controls, displays, and procedures; and presents the results of piloted simulation evaluations of the concept by a cross-section of air transport pilots.

  6. Control system developments for a range of kinematically redundant hydraulic manipulators

    International Nuclear Information System (INIS)

    Smith, A.L.; Rice, P.S.; Thiruarooran, C.

    2000-01-01

    This paper describes a range of control system improvements developed and implemented for in-reactor use during the last three years. Novel control techniques have been developed to provide accurate closed-loop velocity control of pumped hydraulic manipulator joints under a wide range of operating conditions. As a result the supervisory computer system can provide accurate trajectory following, even when more than ten joints are required to move simultaneously. Accurately coordinated motion has given rise to some spectacular gains in in-reactor performance in terms of deployment time, safety and accessibility. The same low-level control improvements have made it feasible to integrate and use the 'geometric controller' to provide accurate resolved motion control of a kinematically redundant manipulator. Examples of recent in-reactor use of all these techniques are given. (author)

  7. Reentry Vehicle Flight Controls Design Guidelines: Dynamic Inversion

    Science.gov (United States)

    Ito, Daigoro; Georgie, Jennifer; Valasek, John; Ward, Donald T.

    2002-01-01

    This report addresses issues in developing a flight control design for vehicles operating across a broad flight regime and with highly nonlinear physical descriptions of motion. Specifically it addresses the need for reentry vehicles that could operate through reentry from space to controlled touchdown on Earth. The latter part of controlled descent is achieved by parachute or paraglider - or by all automatic or a human-controlled landing similar to that of the Orbiter. Since this report addresses the specific needs of human-carrying (not necessarily piloted) reentry vehicles, it deals with highly nonlinear equations of motion, and then-generated control systems must be robust across a very wide range of physics. Thus, this report deals almost exclusively with some form of dynamic inversion (DI). Two vital aspects of control theory - noninteracting control laws and the transformation of nonlinear systems into equivalent linear systems - are embodied in DI. Though there is no doubt that the mathematical tools and underlying theory are widely available, there are open issues as to the practicality of using DI as the only or primary design approach for reentry articles. This report provides a set of guidelines that can be used to determine the practical usefulness of the technique.

  8. A hydraulic hybrid propulsion method for automobiles with self-adaptive system

    International Nuclear Information System (INIS)

    Wu, Wei; Hu, Jibin; Yuan, Shihua; Di, Chongfeng

    2016-01-01

    A hydraulic hybrid vehicle with the self-adaptive system is proposed. The mode-switching between the driving mode and the hydraulic regenerative braking mode is realised by the pressure cross-feedback control. Extensive simulated and tested results are presented. The control parameters are reduced and the energy efficiency can be increased by the self-adaptive system. The mode-switching response is fast. The response time can be adjusted by changing the controlling spool diameter of the hydraulic operated check valve in the self-adaptive system. The closing of the valve becomes faster with a smaller controlling spool diameter. The hydraulic regenerative braking mode can be achieved by changing the hydraulic transformer controlled angle. Compared with the convention electric-hydraulic system, the self-adaptive system for the hydraulic hybrid vehicle mode-switching has a higher reliability and a lower cost. The efficiency of the hydraulic regenerative braking is also increased. - Highlights: • A new hybrid system with a self-adaptive system for automobiles is presented. • The mode-switching is realised by the pressure cross-feedback control. • The energy efficiency can be increased with the self-adaptive system. • The control parameters are reduced with the self-adaptive system.

  9. Integration of Online Parameter Identification and Neural Network for In-Flight Adaptive Control

    Science.gov (United States)

    Hageman, Jacob J.; Smith, Mark S.; Stachowiak, Susan

    2003-01-01

    An indirect adaptive system has been constructed for robust control of an aircraft with uncertain aerodynamic characteristics. This system consists of a multilayer perceptron pre-trained neural network, online stability and control derivative identification, a dynamic cell structure online learning neural network, and a model following control system based on the stochastic optimal feedforward and feedback technique. The pre-trained neural network and model following control system have been flight-tested, but the online parameter identification and online learning neural network are new additions used for in-flight adaptation of the control system model. A description of the modification and integration of these two stand-alone software packages into the complete system in preparation for initial flight tests is presented. Open-loop results using both simulation and flight data, as well as closed-loop performance of the complete system in a nonlinear, six-degree-of-freedom, flight validated simulation, are analyzed. Results show that this online learning system, in contrast to the nonlearning system, has the ability to adapt to changes in aerodynamic characteristics in a real-time, closed-loop, piloted simulation, resulting in improved flying qualities.

  10. Design of The Test Stand for Hydraulic Active Heave Compensation System

    Directory of Open Access Journals (Sweden)

    Jakubowski Arkadiusz

    2017-01-01

    Full Text Available The article presented here described the design of a test stand for hydraulic active heave compensation system. The simulation of sea waves is realized by the use of hydraulic cylinder. A hydraulic motor is used for sea waves compensation. The hydraulic cylinder and the hydraulic motor are controlled by electrohydraulic servo valves. For the measurements Authors used displacement sensor and incremental encoder. Control algorithm is implemented on the PLC. The performed tests included hydraulic actuator and hydraulic motor step responses.

  11. Advanced control techniques for post-buckled precompressed (PBP) flight control actuators

    NARCIS (Netherlands)

    Groen, M.; Van Schravendijk, M.; Barrett, R.; Vos, R.

    2009-01-01

    The dynamic response of a new class of flight control actuators that rely on post-buckled recompressed (PBP) piezoelectric elements is investigated. While past research has proven that PBP actuators are capable of generating deflections three times higher than conventional bimorph actuators, this

  12. NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

    Science.gov (United States)

    Jordan, Thomas L.; Bailey, Roger M.

    2008-01-01

    As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The

  13. Assessment of the State of the Art of Flight Control Technologies as Applicable to Adverse Conditions

    Science.gov (United States)

    Reveley, Mary s.; Briggs, Jeffrey L.; Leone, Karen M.; Kurtoglu, Tolga; Withrow, Colleen A.

    2010-01-01

    Literature from academia, industry, and other Government agencies was surveyed to assess the state of the art in current Integrated Resilient Aircraft Control (IRAC) aircraft technologies. Over 100 papers from 25 conferences from the time period 2004 to 2009 were reviewed. An assessment of the general state of the art in adaptive flight control is summarized first, followed by an assessment of the state of the art as applicable to 13 identified adverse conditions. Specific areas addressed in the general assessment include flight control when compensating for damage or reduced performance, retrofit software upgrades to flight controllers, flight control through engine response, and finally test and validation of new adaptive controllers. The state-of-the-art assessment applicable to the adverse conditions include technologies not specifically related to flight control, but may serve as inputs to a future flight control algorithm. This study illustrates existing gaps and opportunities for additional research by the NASA IRAC Project

  14. Thermally Actuated Hydraulic Pumps

    Science.gov (United States)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

    Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research

  15. Integrated modeling and robust control for full-envelope flight of robotic helicopters

    Science.gov (United States)

    La Civita, Marco

    Robotic helicopters have attracted a great deal of interest from the university, the industry, and the military world. They are versatile machines and there is a large number of important missions that they could accomplish. Nonetheless, there are only a handful of documented examples of robotic-helicopter applications in real-world scenarios. This situation is mainly due to the poor flight performance that can be achieved and---more important---guaranteed under automatic control. Given the maturity of control theory, and given the large body of knowledge in helicopter dynamics, it seems that the lack of success in flying high-performance controllers for robotic helicopters, especially by academic groups and by small industries, has nothing to do with helicopters or control theory as such. The problem lies instead in the large amount of time and resources needed to synthesize, test, and implement new control systems with the approach normally followed in the aeronautical industry. This thesis attempts to provide a solution by presenting a modeling and control framework that minimizes the time, cost, and both human and physical resources necessary to design high-performance flight controllers. The work is divided in two main parts. The first consists of the development of a modeling technique that allows the designer to obtain a high-fidelity model adequate for both real-time simulation and controller design, with few flight, ground, and wind-tunnel tests and a modest level of complexity in the dynamic equations. The second consists of the exploitation of the predictive capabilities of the model and of the robust stability and performance guarantees of the Hinfinity loop-shaping control theory to reduce the number of iterations of the design/simulated-evaluation/flight-test-evaluation procedure. The effectiveness of this strategy is demonstrated by designing and flight testing a wide-envelope high-performance controller for the Carnegie Mellon University robotic

  16. Hydraulic hoisting and backfilling

    Science.gov (United States)

    Sauermann, H. B.

    In a country such as South Africa, with its large deep level mining industry, improvements in mining and hoisting techniques could result in substantial savings. Hoisting techniques, for example, may be improved by the introduction of hydraulic hoisting. The following are some of the advantages of hydraulic hoisting as against conventional skip hoisting: (1) smaller shafts are required because the pipes to hoist the same quantity of ore hydraulically require less space in the shaft than does skip hoisting equipment; (2) the hoisting capacity of a mine can easily be increased without the necessity of sinking new shafts. Large savings in capital costs can thus be made; (3) fully automatic control is possible with hydraulic hoisting and therefore less manpower is required; and (4) health and safety conditions will be improved.

  17. Rapid hydraulic recovery in Eucalyptus pauciflora after drought: linkages between stem hydraulics and leaf gas exchange.

    Science.gov (United States)

    Martorell, Sebastià; Diaz-Espejo, Antonio; Medrano, Hipólito; Ball, Marilyn C; Choat, Brendan

    2014-03-01

    In woody plants, photosynthetic capacity is closely linked to rates at which the plant hydraulic system can supply water to the leaf surface. Drought-induced embolism can cause sharp declines in xylem hydraulic conductivity that coincide with stomatal closure and reduced photosynthesis. Recovery of photosynthetic capacity after drought is dependent on restored xylem function, although few data exist to elucidate this coordination. We examined the dynamics of leaf gas exchange and xylem function in Eucalyptus pauciflora seedlings exposed to a cycle of severe water stress and recovery after re-watering. Stomatal closure and leaf turgor loss occurred at water potentials that delayed the extensive spread of embolism through the stem xylem. Stem hydraulic conductance recovered to control levels within 6 h after re-watering despite a severe drought treatment, suggesting an active mechanism embolism repair. However, stomatal conductance did not recover after 10 d of re-watering, effecting tighter control of transpiration post drought. The dynamics of recovery suggest that a combination of hydraulic and non-hydraulic factors influenced stomatal behaviour post drought. © 2013 John Wiley & Sons Ltd.

  18. Case Study: Test Results of a Tool and Method for In-Flight, Adaptive Control System Verification on a NASA F-15 Flight Research Aircraft

    Science.gov (United States)

    Jacklin, Stephen A.; Schumann, Johann; Guenther, Kurt; Bosworth, John

    2006-01-01

    Adaptive control technologies that incorporate learning algorithms have been proposed to enable autonomous flight control and to maintain vehicle performance in the face of unknown, changing, or poorly defined operating environments [1-2]. At the present time, however, it is unknown how adaptive algorithms can be routinely verified, validated, and certified for use in safety-critical applications. Rigorous methods for adaptive software verification end validation must be developed to ensure that. the control software functions as required and is highly safe and reliable. A large gap appears to exist between the point at which control system designers feel the verification process is complete, and when FAA certification officials agree it is complete. Certification of adaptive flight control software verification is complicated by the use of learning algorithms (e.g., neural networks) and degrees of system non-determinism. Of course, analytical efforts must be made in the verification process to place guarantees on learning algorithm stability, rate of convergence, and convergence accuracy. However, to satisfy FAA certification requirements, it must be demonstrated that the adaptive flight control system is also able to fail and still allow the aircraft to be flown safely or to land, while at the same time providing a means of crew notification of the (impending) failure. It was for this purpose that the NASA Ames Confidence Tool was developed [3]. This paper presents the Confidence Tool as a means of providing in-flight software assurance monitoring of an adaptive flight control system. The paper will present the data obtained from flight testing the tool on a specially modified F-15 aircraft designed to simulate loss of flight control faces.

  19. 1st International Conference on Hydraulic Design in Water Resources Engineering : Channels and Channel Control Structures

    CERN Document Server

    1984-01-01

    The development of water resources has proceeded at an amazing speed around the world in the last few decades. The hydraulic engineer has played his part: in constructing much larger artificial channels than ever before, larger and more sophisticated control structures, and systems of irrigation, drainage and water supply channels in which the flow by its nature is complex and unsteady requiring computer-based techniques at both the design and operation stage. It seemed appropriate to look briefly at some of the developments in hydraulic design resulting from this situation. Hence the idea of the Conference was formed. The Proceedings of the Conference show that hydraulic engineers have been able to acquire a very substantial base of design capability from the experience of the period referred to. The most outstanding development to have occurred is in the combination of physical and mathematical modelling, which in hydraulic engineering has followed a parallel path to that in other branches of engineering sc...

  20. FEEDBACK LINEARISATION APPLIED ON A HYDRAULIC

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Hansen, Michael Rygaard; Pedersen, Henrik C.

    2005-01-01

    is on developing and applying several different feedback linearisation (FL) controllers to the individual servo actuators in a hydraulically driven servo robot to evaluate and compare their possiblities and limitations. This is done based on both simulation and experimental results.......Generally most hydraulic systems are intrensically non-linear, why applying linear control techniques typically results in conservatively dimensioned controllers to obtain stable performance. Non-linear control techniques have the potential of overcoming these problems, and in this paper the focus...

  1. Optimal Control of Nonlinear Hydraulic Networks in the Presence of Disturbance

    DEFF Research Database (Denmark)

    Tahavori, Maryamsadat; Leth, John-Josef; Kallesøe, Carsten

    2014-01-01

    Water leakage is an important component of water loss. Many methods have emerged from urban water supply systems for leakage control, but it still remains a challenge in many countries. Pressure management is an effective way to reduce the leakage in a system. It can also reduce the power...... consumption. To this end, an optimal control strategy is proposed in this paper. In the water supply system model, the hydraulic resistance of the valve is estimated by the real data from a water supply system and it is considered to be a disturbance. The method which is used to solve the nonlinear optimal...

  2. A manned maneuvering unit proximity operations planning and flight guidance display and control system

    Science.gov (United States)

    Gershzohn, Gary R.; Sirko, Robert J.; Zimmerman, K.; Jones, A. D.

    1990-01-01

    This task concerns the design, development, testing, and evaluation of a new proximity operations planning and flight guidance display and control system for manned space operations. A forecast, derivative manned maneuvering unit (MMU) was identified as a candidate for the application of a color, highway-in-the-sky display format for the presentation of flight guidance information. A silicon graphics 4D/20-based simulation is being developed to design and test display formats and operations concepts. The simulation includes the following: (1) real-time color graphics generation to provide realistic, dynamic flight guidance displays and control characteristics; (2) real-time graphics generation of spacecraft trajectories; (3) MMU flight dynamics and control characteristics; (4) control algorithms for rotational and translational hand controllers; (5) orbital mechanics effects for rendezvous and chase spacecraft; (6) inclusion of appropriate navigation aids; and (7) measurement of subject performance. The flight planning system under development provides for: (1) selection of appropriate operational modes, including minimum cost, optimum cost, minimum time, and specified ETA; (2) automatic calculation of rendezvous trajectories, en route times, and fuel requirements; (3) and provisions for manual override. Man/machine function allocations in planning and en route flight segments are being evaluated. Planning and en route data are presented on one screen composed of two windows: (1) a map display presenting a view perpendicular to the orbital plane, depicting flight planning trajectory and time data attitude display presenting attitude and course data for use en route; and (2) an attitude display presenting local vertical-local horizontal attitude data superimposed on a highway-in-the-sky or flight channel representation of the flight planned course. Both display formats are presented while the MMU is en route. In addition to these displays, several original display

  3. Recent developments in the remote radio control of insect flight.

    Science.gov (United States)

    Sato, Hirotaka; Maharbiz, Michel M

    2010-01-01

    The continuing miniaturization of digital circuits and the development of low power radio systems coupled with continuing studies into the neurophysiology and dynamics of insect flight are enabling a new class of implantable interfaces capable of controlling insects in free flight for extended periods. We provide context for these developments, review the state-of-the-art and discuss future directions in this field.

  4. Control rod driving hydraulic pressure device

    International Nuclear Information System (INIS)

    Ogawa, Masahide.

    1993-01-01

    The present invention concerns a control rod driving hydraulic device of a BWR type reactor, and provides an improvement for a means for supplying mechanical seal flashing water of a pump. That is, a mechanical seal flashing pipeline is branched at the downstream of a pressure-reducing orifice and connected to a minimum flow pipeline. With such a constitution, the minimum flow pipeline is connected to a minimum flow pipeline of an auxiliary pump at the downstream of the pressure-reducing orifice and returned to a suction pipeline of the pump. Pressure at the downstream of the pressure-reducing orifice is set, in the orifice, to a pressure required for mechanical seal flashing. Accordingly, the mechanical seal flashing pipeline is connected and a part of minimum flow rate is utilized, thereby enabling to cool mechanical seals. As a result, flow rate of the mechanical flashing water which has been flown out can be saved. The exhaustion amount from the pump can be reduced, to decrease the shaft power and reduce the capacity of the motor. (I.S.)

  5. Integrated Flight and Propulsion Controls for Advanced Aircraft Configurations

    Science.gov (United States)

    Merrill, Walter; Garg, Sanjay

    1995-01-01

    The research vision of the NASA Lewis Research Center in the area of integrated flight and propulsion controls technologies is described. In particular the Integrated Method for Propulsion and Airframe Controls developed at the Lewis Research Center is described including its application to an advanced aircraft configuration. Additionally, future research directions in integrated controls are described.

  6. Continuous Trailing-Edge Flaps for Primary Flight Control of a Helicopter Main Rotor

    Science.gov (United States)

    Thornburgh, Robert P.; Kreshock, Andrew R.; Wilbur, Matthew L.; Sekula, Martin K.; Shen, Jinwei

    2014-01-01

    The use of continuous trailing-edge flaps (CTEFs) for primary flight control of a helicopter main rotor is studied. A practical, optimized bimorph design with Macro-Fiber Composite actuators is developed for CTEF control, and a coupled structures and computational fluid dynamics methodology is used to study the fundamental behavior of an airfoil with CTEFs. These results are used within a comprehensive rotorcraft analysis model to study the control authority requirements of the CTEFs when utilized for primary flight control of a utility class helicopter. A study of the effect of blade root pitch index (RPI) on CTEF control authority is conducted, and the impact of structural and aerodynamic model complexity on the comprehensive analysis results is presented. The results show that primary flight control using CTEFs is promising; however, a more viable option may include the control of blade RPI, as well.

  7. Teaching Thermal Hydraulics & Numerical Methods: An Introductory Control Volume Primer

    Energy Technology Data Exchange (ETDEWEB)

    D. S. Lucas

    2004-10-01

    A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at www.microfusionlab.com.

  8. Learning control of a flight simulator stick

    NARCIS (Netherlands)

    Velthuis, W.J.R.; de Vries, Theodorus J.A.; Vrielink, Koen H.J.; Wierda, G.J.; Borghuis, André

    1998-01-01

    Aimportant part of a flight simulator is its control loading system, which is the part that emulates the behaviour of an aircraft as experienced by the pilot through the stick. Such a system consists of a model of the aircraft that is to be simulated and a stick that is driven by an electric motor.

  9. Extended state observer–based fractional order proportional–integral–derivative controller for a novel electro-hydraulic servo system with iso-actuation balancing and positioning

    Directory of Open Access Journals (Sweden)

    Qiang Gao

    2015-12-01

    Full Text Available Aiming at balancing and positioning of a new electro-hydraulic servo system with iso-actuation configuration, an extended state observer–based fractional order proportional–integral–derivative controller is proposed in this study. To meet the lightweight requirements of heavy barrel weapons with large diameters, an electro-hydraulic servo system with a three-chamber hydraulic cylinder is especially designed. In the electro-hydraulic servo system, the balance chamber of the hydraulic cylinder is used to realize active balancing of the unbalanced forces, while the driving chambers consisting of the upper and lower chambers are adopted for barrel positioning and dynamic compensation of external disturbances. Compared with conventional proportional–integral–derivative controllers, the fractional order proportional–integral–derivative possesses another two adjustable parameters by expanding integer order to arbitrary order calculus, resulting in more flexibility and stronger robustness of the control system. To better compensate for strong external disturbances and system nonlinearities, the extended state observer strategy is further introduced to the fractional order proportional–integral–derivative control system. Numerical simulation and bench test indicate that the extended state observer–based fractional order proportional–integral–derivative significantly outperforms proportional–integral–derivative and fractional order proportional–integral–derivative control systems with better control accuracy and higher system robustness, well demonstrating the feasibility and effectiveness of the proposed extended state observer–based fractional order proportional–integral–derivative control strategy.

  10. Self-Contained Avionics Sensing and Flight Control System for Small Unmanned Aerial Vehicle

    Science.gov (United States)

    Shams, Qamar A. (Inventor); Logan, Michael J. (Inventor); Fox, Robert L. (Inventor); Fox, legal representative, Christopher L. (Inventor); Fox, legal representative, Melanie L. (Inventor); Ingham, John C. (Inventor); Laughter, Sean A. (Inventor); Kuhn, III, Theodore R. (Inventor); Adams, James K. (Inventor); Babel, III, Walter C. (Inventor)

    2011-01-01

    A self-contained avionics sensing and flight control system is provided for an unmanned aerial vehicle (UAV). The system includes sensors for sensing flight control parameters and surveillance parameters, and a Global Positioning System (GPS) receiver. Flight control parameters and location signals are processed to generate flight control signals. A Field Programmable Gate Array (FPGA) is configured to provide a look-up table storing sets of values with each set being associated with a servo mechanism mounted on the UAV and with each value in each set indicating a unique duty cycle for the servo mechanism associated therewith. Each value in each set is further indexed to a bit position indicative of a unique percentage of a maximum duty cycle for the servo mechanism associated therewith. The FPGA is further configured to provide a plurality of pulse width modulation (PWM) generators coupled to the look-up table. Each PWM generator is associated with and adapted to be coupled to one of the servo mechanisms.

  11. Qualification of the flight-critical AFTI/F-16 digital flight control system. [Advanced Fighter Technology Integration

    Science.gov (United States)

    Mackall, D. A.; Ishmael, S. D.; Regenie, V. A.

    1983-01-01

    Qualification considerations for assuring the safety of a life-critical digital flight control system include four major areas: systems interactions, verification, validation, and configuration control. The AFTI/F-16 design, development, and qualification illustrate these considerations. In this paper, qualification concepts, procedures, and methodologies are discussed and illustrated through specific examples.

  12. Mentoring SFRM: A New Approach to International Space Station Flight Controller Training

    Science.gov (United States)

    Huning, Therese; Barshi, Immanuel; Schmidt, Lacey

    2008-01-01

    The Mission Operations Directorate (MOD) of the Johnson Space Center is responsible for providing continuous operations support for the International Space Station (ISS). Operations support requires flight controllers who are skilled in team performance as well as the technical operations of the ISS. Space Flight Resource Management (SFRM), a NASA adapted variant of Crew Resource Management (CRM), is the competency model used in the MOD. ISS flight controller certification has evolved to include a balanced focus on development of SFRM and technical expertise. The latest challenge the MOD faces is how to certify an ISS flight controller (operator) to a basic level of effectiveness in 1 year. SFRM training uses a two-pronged approach to expediting operator certification: 1) imbed SFRM skills training into all operator technical training and 2) use senior flight controllers as mentors. This paper focuses on how the MOD uses senior flight controllers as mentors to train SFRM skills. Methods: A mentor works with an operator throughout the training flow. Inserted into the training flow are guided-discussion sessions and on-the-job observation opportunities focusing on specific SFRM skills, including: situational leadership, conflict management, stress management, cross-cultural awareness, self care and team care while on-console, communication, workload management, and situation awareness. The mentor and operator discuss the science and art behind the skills, cultural effects on skills applications, recognition of good and bad skills applications, recognition of how skills application changes subtly in different situations, and individual goals and techniques for improving skills. Discussion: This mentoring program provides an additional means of transferring SFRM knowledge compared to traditional CRM training programs. Our future endeavors in training SFRM skills (as well as other organization s) may benefit from adding team performance skills mentoring. This paper

  13. Human stick balancing: Tuning Lèvy flights to improve balance control

    Science.gov (United States)

    Cabrera, Juan Luis; Milton, John G.

    2004-09-01

    State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lévy flight. The Lévy index, α, is approximately 0.9; a value close to optimal for a random search. With increased skill, the index α does not change. However, the tails of the Lévy distribution become broader. These observations suggest a Lévy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill level increases. Measurements of the cross-correlation between the position of the tip of the stick and the fingertip demonstrate that the role of closed-loop feedback changes with increased skill. Moreover, estimation of the neural latencies for stick balancing show that for a given stick length, the latency increases with skill level. It is suggested that the neural control for stick balancing involves a mechanism in which brief intervals of consciously generated, corrective movements alternate with longer intervals of prediction-free control. With learning the truncation of the Lévy flight becomes better optimized for balance control and hence the time between successive conscious corrections increases. These observations provide the first evidence that changes in a Lévy flight may have functional significance for the nervous system. This work has implications for the control of balancing problems ranging from falling in the elderly to the design of two-legged robots and earthquake proof buildings.

  14. Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base

    Science.gov (United States)

    Mcruer, Duane T.; Myers, Thomas T.

    1988-01-01

    The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.

  15. UAV Flight Control Based on RTX System Simulation Platform

    Directory of Open Access Journals (Sweden)

    Xiaojun Duan

    2014-03-01

    Full Text Available This paper proposes RTX and Matlab UAV flight control system simulation platform based on the advantages and disadvantages of Windows and real-time system RTX. In the simulation platform, we set the RTW toolbox configuration and modify grt_main.c in order to make simulation platform endowed with online parameter adjustment, fault injection. Meanwhile, we develop the interface of the system simulation platform by CVI, thus it makes effective and has good prospects in application. In order to improve the real-time performance of simulation system, the current computer of real-time simulation mostly use real-time operating system to solve simulation model, as well as dual- framework containing in Host and target machine. The system is complex, high cost, and generally used for the control and half of practical system simulation. For the control system designers, they expect to design control law at a computer with Windows-based environment and conduct real-time simulation. This paper proposes simulation platform for UAV flight control system based on RTX and Matlab for this demand.

  16. New Methodology for Optimal Flight Control using Differential Evolution Algorithms applied on the Cessna Citation X Business Aircraft – Part 2. Validation on Aircraft Research Flight Level D Simulator

    Directory of Open Access Journals (Sweden)

    Yamina BOUGHARI

    2017-06-01

    Full Text Available In this paper the Cessna Citation X clearance criteria were evaluated for a new Flight Controller. The Flight Control Law were optimized and designed for the Cessna Citation X flight envelope by combining the Deferential Evolution algorithm, the Linear Quadratic Regulator method, and the Proportional Integral controller during a previous research presented in part 1. The optimal controllers were used to reach satisfactory aircraft’s dynamic and safe flight operations with respect to the augmentation systems’ handling qualities, and design requirements. Furthermore the number of controllers used to control the aircraft in its flight envelope was optimized using the Linear Fractional Representations features. To validate the controller over the whole aircraft flight envelope, the linear stability, eigenvalue, and handling qualities criteria in addition of the nonlinear analysis criteria were investigated during this research to assess the business aircraft for flight control clearance and certification. The optimized gains provide a very good stability margins as the eigenvalue analysis shows that the aircraft has a high stability, and a very good flying qualities of the linear aircraft models are ensured in its entire flight envelope, its robustness is demonstrated with respect to uncertainties due to its mass and center of gravity variations.

  17. Pilot simulation tests of propulsion control as backup to loss of primary flight controls for a mid-size jet transport

    Science.gov (United States)

    1995-12-01

    Partial failures of aircraft primary flight-control systems and structural : damages to aircraft during flight have led to catastrophic accidents with : subsequent loss of life. These accidents can be prevented if sufficient : alternate control autho...

  18. Development of an interface for an ultrareliable fault-tolerant control system and an electronic servo-control unit

    Science.gov (United States)

    Shaver, Charles; Williamson, Michael

    1986-01-01

    The NASA Ames Research Center sponsors a research program for the investigation of Intelligent Flight Control Actuation systems. The use of artificial intelligence techniques in conjunction with algorithmic techniques for autonomous, decentralized fault management of flight-control actuation systems is explored under this program. The design, development, and operation of the interface for laboratory investigation of this program is documented. The interface, architecturally based on the Intel 8751 microcontroller, is an interrupt-driven system designed to receive a digital message from an ultrareliable fault-tolerant control system (UFTCS). The interface links the UFTCS to an electronic servo-control unit, which controls a set of hydraulic actuators. It was necessary to build a UFTCS emulator (also based on the Intel 8751) to provide signal sources for testing the equipment.

  19. The NASA F-15 Intelligent Flight Control Systems: Generation II

    Science.gov (United States)

    Buschbacher, Mark; Bosworth, John

    2006-01-01

    The Second Generation (Gen II) control system for the F-15 Intelligent Flight Control System (IFCS) program implements direct adaptive neural networks to demonstrate robust tolerance to faults and failures. The direct adaptive tracking controller integrates learning neural networks (NNs) with a dynamic inversion control law. The term direct adaptive is used because the error between the reference model and the aircraft response is being compensated or directly adapted to minimize error without regard to knowing the cause of the error. No parameter estimation is needed for this direct adaptive control system. In the Gen II design, the feedback errors are regulated with a proportional-plus-integral (PI) compensator. This basic compensator is augmented with an online NN that changes the system gains via an error-based adaptation law to improve aircraft performance at all times, including normal flight, system failures, mispredicted behavior, or changes in behavior resulting from damage.

  20. System Design and Performance Test of Hydraulic Intensifier

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Eui; Lee, Gi Chun [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Kim, Jae Hoon [Chungnam National University, Daejeon (Korea, Republic of)

    2010-07-15

    Components such as pressure vessel, hydraulic hose assembly, accumulator, hydraulic cylinder, hydraulic valve, pipe, etc., are tested under the impulse-pressure conditions prescribed in ISO and SAE standards. The impulse pressure test machine needs to have a high pressure, a precise control system and a long life. It should satisfy the requirements for fabrication of the impulse tester to generate ultra high pressure in the hydraulic system. In the impulse tester, a servo-valve control system is adopted; although the control application is convenient, it is expensive owing to the cost of developing the system. The type of the control system determines the pressure wave, which affects the components that are tested. In this study, the manufacturing process and the intensifier system design related to the flow, pressure, and the increasing rate of pressure are investigated. The results indicate the ultra high pressure waves in the system.

  1. Sleep patterns among shift-working flight controllers of the International Space Station: an observational study on the JAXA Flight Control Team.

    Science.gov (United States)

    Mizuno, Koh; Matsumoto, Akiko; Aiba, Tatsuya; Abe, Takashi; Ohshima, Hiroshi; Takahashi, Masaya; Inoue, Yuichi

    2016-09-01

    Flight controllers of the International Space Station (ISS) are engaged in shift work to provide 24-h coverage to support ISS systems. The purpose of this study was to investigate the prevalence and associated factors of shift work sleep disorder (SWSD) among Japanese ISS flight controllers. A questionnaire study was conducted using the Standard Shiftwork Index to evaluate sleep-related problems and possible associated variables. Among 52 respondents out of 73 flight controllers, 30 subjects were identified as night shift workers who worked 3 or more night shifts per month. Those night shift workers who answered "almost always" to questions about experiencing insomnia or excessive sleepiness in any case of work shifts and days off were classified as having SWSD. Additionally, 7 night shift workers participated in supplemental wrist actigraphy data collection for 7 to 8 days including 3 to 4 days of consecutive night shifts. Fourteen of 30 night shift workers were classified as having SWSD. Significant group differences were observed where the SWSD group felt that night shift work was harder and reported more frequent insomniac symptoms after a night shift. However, no other variables demonstrated remarkable differences between groups. Actigraphy results characterized 5 subjects reporting better perceived adaptation as having regular daytime sleep, for 6 to 9 h in total, between consecutive night shifts. On the other hand, 2 subjects reporting perceived maladaptation revealed different sleep patterns, with longer daytime sleep and large day-to-day variation in daytime sleep between consecutive night shifts, respectively. As the tasks for flight control require high levels of alertness and cognitive function, several characteristics, namely shift-working schedule (2 to 4 consecutive night shifts), very short break time (5 to 10 min/h) during work shifts, and cooperative work with onboard astronauts during the evening/night shift, accounted for increasing

  2. Optimization Based Clearance of Flight Control Laws A Civil Aircraft Application

    CERN Document Server

    Hansson, Anders; Puyou, Guilhem

    2012-01-01

    This book summarizes the main achievements of the EC funded 6th Framework Program project COFCLUO – Clearance of Flight Control Laws Using Optimization. This project successfully contributed to the achievement of a top-level objective to meet society’s needs for a more efficient, safer and environmentally friendly air transport by providing new techniques and tools for the clearance of flight control laws. This is an important part of the certification and qualification process of an aircraft – a costly and time-consuming process for the aeronautical industry.   The overall objective of the COFCLUO project was to develop and apply optimization techniques to the clearance of flight control laws in order to improve efficiency and reliability. In the book, the new techniques are explained and benchmarked against traditional techniques currently used by the industry. The new techniques build on mathematical criteria derived from the certification and qualification requirements together with suitable models...

  3. New Methodology for Optimal Flight Control using Differential Evolution Algorithms applied on the Cessna Citation X Business Aircraft – Part 2. Validation on Aircraft Research Flight Level D Simulator

    OpenAIRE

    Yamina BOUGHARI; Georges GHAZI; Ruxandra Mihaela BOTEZ; Florian THEEL

    2017-01-01

    In this paper the Cessna Citation X clearance criteria were evaluated for a new Flight Controller. The Flight Control Law were optimized and designed for the Cessna Citation X flight envelope by combining the Deferential Evolution algorithm, the Linear Quadratic Regulator method, and the Proportional Integral controller during a previous research presented in part 1. The optimal controllers were used to reach satisfactory aircraft’s dynamic and safe flight operations with respect to the augme...

  4. Hydraulics and pneumatics

    CERN Document Server

    Parr, Andrew

    2006-01-01

    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. This is frequently accomplished by means of electrical equipment (such as motors or solenoids), or via devices driven by air (pneumatics) or liquids (hydraulics).This book has been written by a process control engineer as a guide to the operation of hydraulic and pneumatic systems for all engineers and technicians who wish to have an insight into the components and operation of such a system.This second edition has been fully updated to include all recent developments su

  5. Instrumentation and Control Systems for Sodium thermal hydraulic Experiment Loop for Finned-tube sodium-to-Air heat exchanger (SELFA)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byeong Yeon; Kim, Hyung Mo; Cho, Youn Gil; Kim, Jong Man; Ko, Yung Joo; Kang, Byeong Su; Jung, Min Hwan; Jeong, Ji Young [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    A forced-draft sodium-to-air heat exchanger (FHX) is a part of decay heat removal system (DHRS) in Prototype Gen-IV Sodium-cooled fast reactor (PGSFR), which is being developed at Korea Atomic Energy Research Institute (KAERI). Sodium thermal hydraulic Experiment Loop for Finned-tube sodium-to-Air heat exchanger (SELFA) is a test facility for verification and validation of the design code for a forced-draft sodium-to-air heat exchanger (FHX). In this paper, we have provided design and fabrication features for the instrumentation and control systems of SELFA. In general, the instrumentation systems and control systems are coupled for measurement and control of process variables. Instrumentation systems have been designed for investigating thermal-hydraulic characteristics of FHX and control systems have been designed to control the main components (e.g. electromagnetic pumps, heaters, valves etc.) required for test in SELFA. In this paper, we have provided configurations of instrumentation and control systems for Sodium thermal hydraulic Experiment Loop for Finned-tube sodium-to-Air heat exchanger (SELFA). The instrumentation and control systems of SELFA have been implemented based on the expected operation ranges and lesson learned from operational experience of 'Sodium integral effect test loop for safety simulation and assessment-1' (STELLA-1)

  6. Neuromechanism study of insect-machine interface: flight control by neural electrical stimulation.

    Directory of Open Access Journals (Sweden)

    Huixia Zhao

    Full Text Available The insect-machine interface (IMI is a novel approach developed for man-made air vehicles, which directly controls insect flight by either neuromuscular or neural stimulation. In our previous study of IMI, we induced flight initiation and cessation reproducibly in restrained honeybees (Apis mellifera L. via electrical stimulation of the bilateral optic lobes. To explore the neuromechanism underlying IMI, we applied electrical stimulation to seven subregions of the honeybee brain with the aid of a new method for localizing brain regions. Results showed that the success rate for initiating honeybee flight decreased in the order: α-lobe (or β-lobe, ellipsoid body, lobula, medulla and antennal lobe. Based on a comparison with other neurobiological studies in honeybees, we propose that there is a cluster of descending neurons in the honeybee brain that transmits neural excitation from stimulated brain areas to the thoracic ganglia, leading to flight behavior. This neural circuit may involve the higher-order integration center, the primary visual processing center and the suboesophageal ganglion, which is also associated with a possible learning and memory pathway. By pharmacologically manipulating the electrically stimulated honeybee brain, we have shown that octopamine, rather than dopamine, serotonin and acetylcholine, plays a part in the circuit underlying electrically elicited honeybee flight. Our study presents a new brain stimulation protocol for the honeybee-machine interface and has solved one of the questions with regard to understanding which functional divisions of the insect brain participate in flight control. It will support further studies to uncover the involved neurons inside specific brain areas and to test the hypothesized involvement of a visual learning and memory pathway in IMI flight control.

  7. Neuromechanism study of insect-machine interface: flight control by neural electrical stimulation.

    Science.gov (United States)

    Zhao, Huixia; Zheng, Nenggan; Ribi, Willi A; Zheng, Huoqing; Xue, Lei; Gong, Fan; Zheng, Xiaoxiang; Hu, Fuliang

    2014-01-01

    The insect-machine interface (IMI) is a novel approach developed for man-made air vehicles, which directly controls insect flight by either neuromuscular or neural stimulation. In our previous study of IMI, we induced flight initiation and cessation reproducibly in restrained honeybees (Apis mellifera L.) via electrical stimulation of the bilateral optic lobes. To explore the neuromechanism underlying IMI, we applied electrical stimulation to seven subregions of the honeybee brain with the aid of a new method for localizing brain regions. Results showed that the success rate for initiating honeybee flight decreased in the order: α-lobe (or β-lobe), ellipsoid body, lobula, medulla and antennal lobe. Based on a comparison with other neurobiological studies in honeybees, we propose that there is a cluster of descending neurons in the honeybee brain that transmits neural excitation from stimulated brain areas to the thoracic ganglia, leading to flight behavior. This neural circuit may involve the higher-order integration center, the primary visual processing center and the suboesophageal ganglion, which is also associated with a possible learning and memory pathway. By pharmacologically manipulating the electrically stimulated honeybee brain, we have shown that octopamine, rather than dopamine, serotonin and acetylcholine, plays a part in the circuit underlying electrically elicited honeybee flight. Our study presents a new brain stimulation protocol for the honeybee-machine interface and has solved one of the questions with regard to understanding which functional divisions of the insect brain participate in flight control. It will support further studies to uncover the involved neurons inside specific brain areas and to test the hypothesized involvement of a visual learning and memory pathway in IMI flight control.

  8. Neuromechanism Study of Insect–Machine Interface: Flight Control by Neural Electrical Stimulation

    Science.gov (United States)

    Zhao, Huixia; Zheng, Nenggan; Ribi, Willi A.; Zheng, Huoqing; Xue, Lei; Gong, Fan; Zheng, Xiaoxiang; Hu, Fuliang

    2014-01-01

    The insect–machine interface (IMI) is a novel approach developed for man-made air vehicles, which directly controls insect flight by either neuromuscular or neural stimulation. In our previous study of IMI, we induced flight initiation and cessation reproducibly in restrained honeybees (Apis mellifera L.) via electrical stimulation of the bilateral optic lobes. To explore the neuromechanism underlying IMI, we applied electrical stimulation to seven subregions of the honeybee brain with the aid of a new method for localizing brain regions. Results showed that the success rate for initiating honeybee flight decreased in the order: α-lobe (or β-lobe), ellipsoid body, lobula, medulla and antennal lobe. Based on a comparison with other neurobiological studies in honeybees, we propose that there is a cluster of descending neurons in the honeybee brain that transmits neural excitation from stimulated brain areas to the thoracic ganglia, leading to flight behavior. This neural circuit may involve the higher-order integration center, the primary visual processing center and the suboesophageal ganglion, which is also associated with a possible learning and memory pathway. By pharmacologically manipulating the electrically stimulated honeybee brain, we have shown that octopamine, rather than dopamine, serotonin and acetylcholine, plays a part in the circuit underlying electrically elicited honeybee flight. Our study presents a new brain stimulation protocol for the honeybee–machine interface and has solved one of the questions with regard to understanding which functional divisions of the insect brain participate in flight control. It will support further studies to uncover the involved neurons inside specific brain areas and to test the hypothesized involvement of a visual learning and memory pathway in IMI flight control. PMID:25409523

  9. Initial virtual flight test for a dynamically similar aircraft model with control augmentation system

    Directory of Open Access Journals (Sweden)

    Linliang Guo

    2017-04-01

    Full Text Available To satisfy the validation requirements of flight control law for advanced aircraft, a wind tunnel based virtual flight testing has been implemented in a low speed wind tunnel. A 3-degree-of-freedom gimbal, ventrally installed in the model, was used in conjunction with an actively controlled dynamically similar model of aircraft, which was equipped with the inertial measurement unit, attitude and heading reference system, embedded computer and servo-actuators. The model, which could be rotated around its center of gravity freely by the aerodynamic moments, together with the flow field, operator and real time control system made up the closed-loop testing circuit. The model is statically unstable in longitudinal direction, and it can fly stably in wind tunnel with the function of control augmentation of the flight control laws. The experimental results indicate that the model responds well to the operator’s instructions. The response of the model in the tests shows reasonable agreement with the simulation results. The difference of response of angle of attack is less than 0.5°. The effect of stability augmentation and attitude control law was validated in the test, meanwhile the feasibility of virtual flight test technique treated as preliminary evaluation tool for advanced flight vehicle configuration research was also verified.

  10. Cost Estimation and Control for Flight Systems

    Science.gov (United States)

    Hammond, Walter E.; Vanhook, Michael E. (Technical Monitor)

    2002-01-01

    Good program management practices, cost analysis, cost estimation, and cost control for aerospace flight systems are interrelated and depend upon each other. The best cost control process cannot overcome poor design or poor systems trades that lead to the wrong approach. The project needs robust Technical, Schedule, Cost, Risk, and Cost Risk practices before it can incorporate adequate Cost Control. Cost analysis both precedes and follows cost estimation -- the two are closely coupled with each other and with Risk analysis. Parametric cost estimating relationships and computerized models are most often used. NASA has learned some valuable lessons in controlling cost problems, and recommends use of a summary Project Manager's checklist as shown here.

  11. Combined hydraulic and regenerative braking system

    Science.gov (United States)

    Venkataperumal, R.R.; Mericle, G.E.

    1979-08-09

    A combined hydraulic and regenerative braking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  12. Robust Non-Chattering Observer Based Sliding Control Concept for Electro-Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper presents an observer-based sliding mode control concept with chattering reduction, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD's). The proposed control concept requires only common data sheet information and no knowledge on load...... extensive knowledge on system parameters nor advanced control theory. In order to accomplish this task, an integral sliding mode controller designed for the control derivative employing state observation is proposed, based on a generalized reduced order model structure of a VCD with unmatched valve ow......- and cylinder asymmetries. It is shown that limited attention can be given to bounds on parameter estimates, that chattering is reduced and the number of tuning parameters is reduced to the level seen in conventional PID schemes. Furthermore, simulation results demonstrate a high level of robustness when...

  13. IT-Tools Concept for Simulation and Design of Water Hydraulic Mechatronic Test Facilities for Motion Control and Operation in Environmentally Sensitive Application Areas

    DEFF Research Database (Denmark)

    Conrad, Finn; Pobedza, J.; Sobczyk, A.

    2004-01-01

    This paper presents a proposed IT-Tools concept for modeling, simulation, analysis and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. The designed test rigs have tap water hydraulic components of the Danfoss Nessie® product family and equipped...... with a measurement and data acquisition system. Results of the mathematical modeling, simulation and design of the motion control test rigs are presented. Furthermore, the paper presents selected experimental and identifying test results for the water hydraulic test rigs....

  14. Post-Buckled Precompressed (PBP) piezoelectric actuators for UAV flight control

    NARCIS (Netherlands)

    Vos, R.; Barrett, R.; Krakers, L.; Van Tooren, M.

    2006-01-01

    This paper presents the use of a new class of flight control actuators employing Post-Buckled Precompressed (PBP) piezoelectric elements in morphing wing Uninhabited Aerial Vehicles (UAVs). The new actuator relieson axial compression to amplify deflections and control forces simultaneously. Two

  15. Hydraulic actuators for flexible robots : a flatness based approach for tracking and vibration control

    NARCIS (Netherlands)

    Wey, T.; Lemmen, M.; Bernzen, W.; Wey, T.

    1999-01-01

    This paper deals with an application of the differential algebraic flatness approach to hydraulic drives. Here, an elastic robot arm driven by a differential cylinder is investigated. The task is to design a suitable control law which not only tracks a given trajectory but also allows the damping of

  16. Experimental-based Modelling and Simulation of Water Hydraulic Mechatronics Test Facilities for Motion Control and Operation in Environmental Sensitive Applications` Areas

    DEFF Research Database (Denmark)

    Conrad, Finn; Pobedza, J.; Sobczyk, A.

    2003-01-01

    The paper presents experimental-based modelling, simulation, analysis and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. The contributions includes results from on-going research projects on fluid power and mechatronics based on tap water hydraulic...

  17. Autonomous formation flight of helicopters: Model predictive control approach

    Science.gov (United States)

    Chung, Hoam

    Formation flight is the primary movement technique for teams of helicopters. However, the potential for accidents is greatly increased when helicopter teams are required to fly in tight formations and under harsh conditions. This dissertation proposes that the automation of helicopter formations is a realistic solution capable of alleviating risks. Helicopter formation flight operations in battlefield situations are highly dynamic and dangerous, and, therefore, we maintain that both a high-level formation management system and a distributed coordinated control algorithm should be implemented to help ensure safe formations. The starting point for safe autonomous formation flights is to design a distributed control law attenuating external disturbances coming into a formation, so that each vehicle can safely maintain sufficient clearance between it and all other vehicles. While conventional methods are limited to homogeneous formations, our decentralized model predictive control (MPC) approach allows for heterogeneity in a formation. In order to avoid the conservative nature inherent in distributed MPC algorithms, we begin by designing a stable MPC for individual vehicles, and then introducing carefully designed inter-agent coupling terms in a performance index. Thus the proposed algorithm works in a decentralized manner, and can be applied to the problem of helicopter formations comprised of heterogenous vehicles. Individual vehicles in a team may be confronted by various emerging situations that will require the capability for in-flight reconfiguration. We propose the concept of a formation manager to manage separation, join, and synchronization of flight course changes. The formation manager accepts an operator's commands, information from neighboring vehicles, and its own vehicle states. Inside the formation manager, there are multiple modes and complex mode switchings represented as a finite state machine (FSM). Based on the current mode and collected

  18. Hydraulics and pneumatics a technician's and engineer's guide

    CERN Document Server

    Parr, Andrew

    1991-01-01

    Hydraulics and Pneumatics: A Technician's and Engineer's Guide provides an introduction to the components and operation of a hydraulic or pneumatic system. This book discusses the main advantages and disadvantages of pneumatic or hydraulic systems.Organized into eight chapters, this book begins with an overview of industrial prime movers. This text then examines the three different types of positive displacement pump used in hydraulic systems, namely, gear pumps, vane pumps, and piston pumps. Other chapters consider the pressure in a hydraulic system, which can be quickly and easily controlled

  19. Thermal hydraulics of the impurity control system for FED/INTOR

    International Nuclear Information System (INIS)

    Cha, Y.S.; Mattas, R.F.; Abdou, M.A.; Haines, J.R.

    1983-01-01

    This paper addresses two important aspects of thermal hydraulics related to the design of the impurity control system (limiter and divertor) of the Fusion Engineering Device (FED) and the International Tokamak Reactor (INTOR). The first part of the paper is devoted to the determination of temperature distributions in various combinations of the coating/structural materials proposed for the limiter/divertor of FED and INTOR. The second part of the paper describes the analysis of the tangential motion of the melt layer under the influence of magnetic force during plasma disruption. The results of both analysis provide inputs to the determination of the life time of the limiter (or divertor) which is the most critical problem for the impurity control system as far as engineering and materials consideration is concerned

  20. Proceedings of the 1991 national conference on hydraulic engineering

    International Nuclear Information System (INIS)

    Shane, R.M.

    1991-01-01

    This book contains the proceedings of the 1991 National Conference of Hydraulic Engineering. The conference was held in conjunction with the International Symposium on Ground Water and a Software Exchange that facilitated exchange of information on recent software developments of interest to hydraulic engineers. Also included in the program were three mini-symposia on the Exclusive Economic Zone, Data Acquisition, and Appropriate Technology. Topics include sedimentation; appropriate technology; exclusive economic zone hydraulics; hydraulic data acquisition and display; innovative hydraulic structures and water quality applications of hydraulic research, including the hydraulics of aerating turbines; wetlands; hydraulic and hydrologic extremes; highway drainage; overtopping protection of dams; spillway design; coastal and estuarine hydraulics; scale models; computation hydraulics; GIS and expert system applications; watershed response to rainfall; probabilistic approaches; and flood control investigations

  1. Simpler ISS Flight Control Communications and Log Keeping via Social Tools and Techniques

    Science.gov (United States)

    Scott, David W.; Cowart, Hugh; Stevens, Dan

    2012-01-01

    The heart of flight operations control involves a) communicating effectively in real time with other controllers in the room and/or in remote locations and b) tracking significant events, decisions, and rationale to support the next set of decisions, provide a thorough shift handover, and troubleshoot/improve operations. International Space Station (ISS) flight controllers speak with each other via multiple voice circuits or loops, each with a particular purpose and constituency. Controllers monitor and/or respond to several loops concurrently. The primary tracking tools are console logs, typically kept by a single operator and not visible to others in real-time. Information from telemetry, commanding, and planning systems also plays into decision-making. Email is very secondary/tertiary due to timing and archival considerations. Voice communications and log entries supporting ISS operations have increased by orders of magnitude because the number of control centers, flight crew, and payload operations have grown. This paper explores three developmental ground system concepts under development at Johnson Space Center s (JSC) Mission Control Center Houston (MCC-H) and Marshall Space Flight Center s (MSFC) Payload Operations Integration Center (POIC). These concepts could reduce ISS control center voice traffic and console logging yet increase the efficiency and effectiveness of both. The goal of this paper is to kindle further discussion, exploration, and tool development.

  2. A Study on the Air Vent Valve of the Hydraulic Servo Actuator for Steam Control of Power Plants

    International Nuclear Information System (INIS)

    Lee, Yong Bum; Lee, Jong Jik

    2016-01-01

    To produce adequate electricity in nuclear and thermal power plants, an optimal amount of steam should be supplied to a generator connected to high- and low-pressure steam turbines. A turbine output control device, which is a special steam valve employed to supply or interrupt the steam to the turbine, is operated using a hydraulic servo actuator. In power plants, the performance of servo actuators is degraded by the air generated from the hydraulic system, or causes frequent failures owing to an increase in the wear of the seal. This is due to the seal being burnt as generated heat using the produced compressed air. Some power plants have exhausted air using a fixed orifice, and thus they encounter power loss due to mass flow exhaust. Failures are generated in hydraulic pumps, electric motors, and valves, which are frequently operated. In this study, we perform modeling and analysis of the load-sensing air-exhaust valves, which can be passed through very fine flow under normal use conditions, and exhaust mass flow air at the beginning stage as with existing fixed orifices. Then, we propose a method to prevent failures due to the compressed air, and to ensure the control accuracy of hydraulic servo actuators.

  3. A Study on the Air Vent Valve of the Hydraulic Servo Actuator for Steam Control of Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Lee, Jong Jik [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2016-06-15

    To produce adequate electricity in nuclear and thermal power plants, an optimal amount of steam should be supplied to a generator connected to high- and low-pressure steam turbines. A turbine output control device, which is a special steam valve employed to supply or interrupt the steam to the turbine, is operated using a hydraulic servo actuator. In power plants, the performance of servo actuators is degraded by the air generated from the hydraulic system, or causes frequent failures owing to an increase in the wear of the seal. This is due to the seal being burnt as generated heat using the produced compressed air. Some power plants have exhausted air using a fixed orifice, and thus they encounter power loss due to mass flow exhaust. Failures are generated in hydraulic pumps, electric motors, and valves, which are frequently operated. In this study, we perform modeling and analysis of the load-sensing air-exhaust valves, which can be passed through very fine flow under normal use conditions, and exhaust mass flow air at the beginning stage as with existing fixed orifices. Then, we propose a method to prevent failures due to the compressed air, and to ensure the control accuracy of hydraulic servo actuators.

  4. How far can various control options take us in terms of increased hydraulic capacity under wet weather conditions?

    DEFF Research Database (Denmark)

    Sharma, Anitha Kumari; Guildal, T.; Thomsen, H. A. R.

    Many modelling studies have demonstrated that the hydraulic capacity of the WWTP can be improved by introducing various real time control options, however few studies have demonstrated how effective these controls are in the real world....

  5. The Flight Control System of the Hovereye (Trademark) VTOL UAV

    Science.gov (United States)

    2007-05-01

    10 RTO-MP-AVT-146 UNCLASSIFIED/UNLIMITED UNCLASSIFIED/UNLIMITED Envelope protection -+ SISO linear Controllers α_dotc Cinematic decoupler ωc αest...T. Ward, “Reentry Vehicle Flight Controls Design Guidelines: Dynamic Inversion”, NASA/TP-2002–210771, March 2002 [14] Pollini, L., Innocenti, M

  6. A four-axis hand controller for helicopter flight control

    Science.gov (United States)

    Demaio, Joe

    1993-01-01

    A proof-of-concept hand controller for controlling lateral and longitudinal cyclic pitch, collective pitch and tail rotor thrust was developed. The purpose of the work was to address problems of operator fatigue, poor proprioceptive feedback and cross-coupling of axes associated with many four-axis controller designs. The present design is an attempt to reduce cross-coupling to a level that can be controlled with breakout force, rather than to eliminate it entirely. The cascaded design placed lateral and longitudinal cyclic in their normal configuration. Tail rotor thrust was placed atop the cyclic controller. A left/right twisting motion with the wrist made the control input. The axis of rotation was canted outboard (clockwise) to minimize cross-coupling with the cyclic pitch axis. The collective control was a twist grip, like a motorcycle throttle. Measurement of the amount of cross-coupling involved in pure, single-axis inputs showed cross coupling under 10 percent of full deflection for all axes. This small amount of cross-coupling could be further reduced with better damping and force gradient control. Fatigue was not found to be a problem, and proprioceptive feedback was adequate for all flight tasks executed.

  7. Direct Evidence for Vision-based Control of Flight Speed in Budgerigars.

    Science.gov (United States)

    Schiffner, Ingo; Srinivasan, Mandyam V

    2015-06-05

    We have investigated whether, and, if so, how birds use vision to regulate the speed of their flight. Budgerigars, Melopsittacus undulatus, were filmed in 3-D using high-speed video cameras as they flew along a 25 m tunnel in which stationary or moving vertically oriented black and white stripes were projected on the side walls. We found that the birds increased their flight speed when the stripes were moved in the birds' flight direction, but decreased it only marginally when the stripes were moved in the opposite direction. The results provide the first direct evidence that Budgerigars use cues based on optic flow, to regulate their flight speed. However, unlike the situation in flying insects, it appears that the control of flight speed in Budgerigars is direction-specific. It does not rely solely on cues derived from optic flow, but may also be determined by energy constraints.

  8. Tether dynamics and control results for tethered satellite system's initial flight

    Science.gov (United States)

    Chapel, Jim D.; Flanders, Howard

    The recent Tethered Satellite System-1 (TSS-1) mission has provided a wealth of data concerning the dynamics of tethered systems in space and has demonstrated the effectiveness of operational techniques designed to control these dynamics. In this paper, we review control techniques developed for managing tether dynamics, and discuss the results of using these techniques for the Tethered Satellite System's maiden flight on STS-46. In particular, the flight results of controlling libration dynamics, string dynamics, and slack tether are presented. These results show that tether dynamics can be safely managed. The overall stability of the system was found to be surprisingly good even at relatively short tether lengths. In fact, the system operated in passive mode at a tether length of 256 meters for over 9 hours. Only monitoring of the system was required during this time. Although flight anomalies prevented the planned deployment to 20 km, the extended operations at shorter tether lengths have proven the viability of using tethers in space. These results should prove invaluable in preparing for future missions with tethered objects in space.

  9. Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations of Adverse Interactions Using a Piloted Aircraft

    Science.gov (United States)

    Hanson, Curt; Miller, Chris; Wall, John H.; Vanzwieten, Tannen S.; Gilligan, Eric; Orr, Jeb S.

    2015-01-01

    An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority. Two NASA research pilots flew a total of twenty five constant pitch-rate trajectories using a prototype manual steering mode with and without adaptive control.

  10. Balancing Training Techniques for Flight Controller Certification

    Science.gov (United States)

    Gosling, Christina

    2011-01-01

    Training of ground control teams has been a difficult task in space operations. There are several intangible skills that must be learned to become the steely eyed men and women of mission control who respond to spacecraft failures that can lead to loss of vehicle or crew if handled improperly. And as difficult as training is, it can also be costly. Every day, month or year an operator is in training, is a day that not only they are being trained without direct benefit to the organization, but potentially an instructor or mentor is also being paid for hours spent assisting them. Therefore, optimization of the training flow is highly desired. Recently the Expedition Division (DI) at Johnson Space Flight Center has recreated their training flows for the purpose of both moving to an operator/specialist/instructor hierarchy and to address past inefficiencies in the training flow. This paper will discuss the types of training DI is utilizing in their new flows, and the balance that has been struck between the ideal learning environments and realistic constraints. Specifically, the past training flow for the ISS Attitude Determination and Control Officer will be presented, including drawbacks that were encountered. Then the new training flow will be discussed and how a new approach utilizes more training methods and teaching techniques. We will look at how DI has integrated classes, workshops, checkouts, module reviews, scenarios, OJT, paper sims, Mini Sims, and finally Integrated Sims to balance the cost and timing of training a new flight controller.

  11. A robust rotorcraft flight control system design methodology utilizing quantitative feedback theory

    Science.gov (United States)

    Gorder, Peter James

    1993-01-01

    Rotorcraft flight control systems present design challenges which often exceed those associated with fixed-wing aircraft. First, large variations in the response characteristics of the rotorcraft result from the wide range of airspeeds of typical operation (hover to over 100 kts). Second, the assumption of vehicle rigidity often employed in the design of fixed-wing flight control systems is rarely justified in rotorcraft where rotor degrees of freedom can have a significant impact on the system performance and stability. This research was intended to develop a methodology for the design of robust rotorcraft flight control systems. Quantitative Feedback Theory (QFT) was chosen as the basis for the investigation. Quantitative Feedback Theory is a technique which accounts for variability in the dynamic response of the controlled element in the design robust control systems. It was developed to address a Multiple-Input Single-Output (MISO) design problem, and utilizes two degrees of freedom to satisfy the design criteria. Two techniques were examined for extending the QFT MISO technique to the design of a Multiple-Input-Multiple-Output (MIMO) flight control system (FCS) for a UH-60 Black Hawk Helicopter. In the first, a set of MISO systems, mathematically equivalent to the MIMO system, was determined. QFT was applied to each member of the set simultaneously. In the second, the same set of equivalent MISO systems were analyzed sequentially, with closed loop response information from each loop utilized in subsequent MISO designs. The results of each technique were compared, and the advantages of the second, termed Sequential Loop Closure, were clearly evident.

  12. Use of ILTV Control Laws for LaNCETS Flight Research

    Science.gov (United States)

    Moua, Cheng

    2010-01-01

    A report discusses the Lift and Nozzle Change Effects on Tail Shock (LaNCETS) test to investigate the effects of lift distribution and nozzle-area ratio changes on tail shock strength of an F-15 aircraft. Specific research objectives are to obtain inflight shock strength for multiple combinations of nozzle-area ratio and lift distribution; compare results with preflight prediction tools; and update predictive tools with flight results. The objectives from a stability and control perspective are to ensure adequate aircraft stability for the changes in lift distribution and plume shape, and ensure manageable transient from engaging and disengaging the ILTV research control laws. In order to change the lift distribution and plume shape of the F-15 aircraft, a decade-old Inner Loop Thrust Vectoring (ILTV) research control law was used. Flight envelope expansion was performed for the test configuration and flight conditions prior to the probing test points. The approach for achieving the research objectives was to utilize the unique capabilities of NASA's NF-15B-837 aircraft to allow the adjustment of the nozzle-area ratio and/or canard positions by engaging the ILTV research control laws. The ILTV control laws provide the ability to add trim command biases to canard positions, nozzle area ratios, and thrust vectoring through the use of datasets. Datasets consist of programmed test inputs (PTIs) that define trims to change the nozzle-area ratio and/or canard positions. The trims are applied as increments to the normally commanded positions. A LaNCETS non-linear, six-degrees-of-freedom simulation capable of realtime pilot-in-the-loop, hardware-in-the-loop, and non-real-time batch support was developed and validated. Prior to first flight, extensive simulation analyses were performed to show adequate stability margins with the changes in lift distribution and plume shape. Additionally, engagement/disengagement transient analysis was also performed to show manageable

  13. ANALYSIS OF AIR TRAFFIC CONTROL MANAGEMENT AT AIRPORTS WITH LOW FLIGHT INTENSITY IN FOREIGN COUNTRIES

    Directory of Open Access Journals (Sweden)

    Evgenii E. Nechaev

    2017-01-01

    Full Text Available This article discusses various options for air traffic management at low flight intensity airports and airports located remotely in the North, where air traffic control service is not necessary.There are some examples of already implemented concepts in foreign countries: such as remote control tower, which allows to control air traffic, being at a considerable distance from the airport. Such a remote control tower is already put into operation at the Örnsköldsvik airport (Sweden. The prospects of this system development in other countries are observed in this article. A remote control tower will also appear in the United States in the nearest future. Also the paper considers the pros and cons of this system and its effect on flight safety.Moreover, there are given the examples of using non-towered and uncontrolled airports, where air traffic control service is not provided. This kind of airports is partly used in the USA and in New Zealand. The article describes flight procedures in the area of uncontrolled airports, including visual flight rules and instrument flight rules.We also analyze the possibilities of remote control towers and uncontrolled airports adaptation in the Russian Federation. It is a very important problem for Russia because most airports do not provide more than 10 movements per day. But air traffic control service exists in all airports.

  14. Teaching Thermal Hydraulics and Numerical Methods: An Introductory Control Volume Primer

    International Nuclear Information System (INIS)

    D. S. Lucas

    2004-01-01

    A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at www.microfusionlab.com

  15. Two Reconfigurable Flight-Control Design Methods: Robust Servomechanism and Control Allocation

    Science.gov (United States)

    Burken, John J.; Lu, Ping; Wu, Zheng-Lu; Bahm, Cathy

    2001-01-01

    Two methods for control system reconfiguration have been investigated. The first method is a robust servomechanism control approach (optimal tracking problem) that is a generalization of the classical proportional-plus-integral control to multiple input-multiple output systems. The second method is a control-allocation approach based on a quadratic programming formulation. A globally convergent fixed-point iteration algorithm has been developed to make onboard implementation of this method feasible. These methods have been applied to reconfigurable entry flight control design for the X-33 vehicle. Examples presented demonstrate simultaneous tracking of angle-of-attack and roll angle commands during failures of the fight body flap actuator. Although simulations demonstrate success of the first method in most cases, the control-allocation method appears to provide uniformly better performance in all cases.

  16. Improvement of diesel engine performance by hydraulically powered electronic control (mechatronics) system. Hakuyo diesel kikan no mechatronics system ni yoru seino kojo

    Energy Technology Data Exchange (ETDEWEB)

    Sonoda, K.; Nakamura, Y.; Kajima, T.; Sato, S.; Fujii, T.; Tobe, Y. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))

    1992-07-20

    This paper describes new hydraulically-actuated mechanisms for both fuel injection and inlet/exhaust valve operation of diesel engines through solenoid valves, which obviate the conventional cam-driven system. These mechanisms were integrated with an electronic control unit also developed in this study and they were mounted as a mechatronics system'' on a power-increased single-cylinder engine. This mechatronics system was mainly composed of an injection control. boost and accumulation component, an inlet and exhaust valve control component, a solenoid valve, an electronic control equipment, a hydraulic power unit, and a maneuvering unit. The verification test was carried out for the improvement of diesel engine performance by the hydraulically powered mechatronics system. As a result, it was proved not only that these mechanisms provide stable operating characteristics over a wide range of conditions, but also that the electronic control system allows accurate, smooth response. 3 refs., 23 figs., 2 tabs.

  17. Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

    Directory of Open Access Journals (Sweden)

    Jian Fu

    2017-02-01

    Full Text Available In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortunately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now available on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling, thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power network pollution analysis and fault response.

  18. Launch Vehicle Manual Steering with Adaptive Augmenting Control:In-Flight Evaluations of Adverse Interactions Using a Piloted Aircraft

    Science.gov (United States)

    Hanson, Curt; Miller, Chris; Wall, John H.; VanZwieten, Tannen S.; Gilligan, Eric T.; Orr, Jeb S.

    2015-01-01

    An Adaptive Augmenting Control (AAC) algorithm for the Space Launch System (SLS) has been developed at the Marshall Space Flight Center (MSFC) as part of the launch vehicle's baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a potential manual steering mode were also investigated by giving the pilot trajectory deviation cues and pitch rate command authority, which is the subject of this paper. Two NASA research pilots flew a total of 25 constant pitch rate trajectories using a prototype manual steering mode with and without adaptive control, evaluating six different nominal and off-nominal test case scenarios. Pilot comments and PIO ratings were given following each trajectory and correlated with aircraft state data and internal controller signals post-flight.

  19. Control and Non-Payload Communications (CNPC) Prototype Radio - Generation 2 Security Flight Test Report

    Science.gov (United States)

    Iannicca, Dennis C.; Ishac, Joseph A.; Shalkhauser, Kurt A.

    2015-01-01

    NASA Glenn Research Center (GRC), in cooperation with Rockwell Collins, is working to develop a prototype Control and Non-Payload Communications (CNPC) radio platform as part of NASA Integrated Systems Research Program's (ISRP) Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) project. A primary focus of the project is to work with the Federal Aviation Administration (FAA) and industry standards bodies to build and demonstrate a safe, secure, and efficient CNPC architecture that can be used by industry to evaluate the feasibility of deploying a system using these technologies in an operational capacity. GRC has been working in conjunction with these groups to assess threats, identify security requirements, and to develop a system of standards-based security controls that can be applied to the GRC prototype CNPC architecture as a demonstration platform. The proposed security controls were integrated into the GRC flight test system aboard our S-3B Viking surrogate aircraft and several network tests were conducted during a flight on November 15th, 2014 to determine whether the controls were working properly within the flight environment. The flight test was also the first to integrate Robust Header Compression (ROHC) as a means of reducing the additional overhead introduced by the security controls and Mobile IPv6. The effort demonstrated the complete end-to-end secure CNPC link in a relevant flight environment.

  20. Hummingbirds control hovering flight by stabilizing visual motion.

    Science.gov (United States)

    Goller, Benjamin; Altshuler, Douglas L

    2014-12-23

    Relatively little is known about how sensory information is used for controlling flight in birds. A powerful method is to immerse an animal in a dynamic virtual reality environment to examine behavioral responses. Here, we investigated the role of vision during free-flight hovering in hummingbirds to determine how optic flow--image movement across the retina--is used to control body position. We filmed hummingbirds hovering in front of a projection screen with the prediction that projecting moving patterns would disrupt hovering stability but stationary patterns would allow the hummingbird to stabilize position. When hovering in the presence of moving gratings and spirals, hummingbirds lost positional stability and responded to the specific orientation of the moving visual stimulus. There was no loss of stability with stationary versions of the same stimulus patterns. When exposed to a single stimulus many times or to a weakened stimulus that combined a moving spiral with a stationary checkerboard, the response to looming motion declined. However, even minimal visual motion was sufficient to cause a loss of positional stability despite prominent stationary features. Collectively, these experiments demonstrate that hummingbirds control hovering position by stabilizing motions in their visual field. The high sensitivity and persistence of this disruptive response is surprising, given that the hummingbird brain is highly specialized for sensory processing and spatial mapping, providing other potential mechanisms for controlling position.

  1. Controlling Precision Stepper Motors in Flight Using (Almost) No Parts

    Science.gov (United States)

    Randall, David

    2010-01-01

    This concept allows control of high-performance stepper motors with minimal parts count and minimal flight software complexity. Although it uses a small number of common flight-qualified parts and simple control algorithms, it is capable enough to meet demanding system requirements. Its programmable nature makes it trivial to implement changes to control algorithms both during integration & test and in flight. Enhancements such as microstepping, half stepping, back-emf compensation, and jitter reduction can be tailored to the requirements of a large variety of stepper motor based applications including filter wheels, focus mechanisms, antenna tracking subsystems, pointing and mobility. The hardware design (using an H-bridge motor controller IC) was adapted from JPL's MER mission, still operating on Mars. This concept has been fully developed and incorporated into the MCS instrument on MRO, currently operating in Mars orbit. It has been incorporated into the filter wheel mechanism and linear stage (focus) mechanism for the AMT instrument. On MCS/MRO, two of these circuits control the elevation and azimuth of the MCS telescope/radiometer assembly, allowing the instrument to continuously monitor the limb of the Martian atmosphere. Implementation on MCS/MRO resulted in a 4:1 reduction in the volume and mass required for the motor driver electronics (100:25 square inches of PCB space), producing a very compact instrument. In fact, all of the electronics for the MCS instrument are packaged within the movable instrument structure. It also saved approximately 3 Watts of power. Most importantly, the design enabled MCS to meet very its stringent maximum allowable torque disturbance requirements.

  2. Control for small-speed lateral flight in a model insect

    International Nuclear Information System (INIS)

    Zhang Yanlai; Sun Mao

    2011-01-01

    Controls required for small-speed lateral flight of a model insect were studied using techniques based on the linear theories of stability and control (the stability and control derivatives were computed by the method of computational fluid dynamics). The main results are as follows. (1) Two steady-state lateral motions can exist: one is a horizontal side translation with the body rolling to the same side of the translation by a small angle, and the other is a constant-rate yaw rotation (rotation about the vertical axis). (2) The side translation requires an anti-symmetrical change in the stroke amplitudes of the contralateral wings, and/or an anti-symmetrical change in the angles of attack of the contralateral wings, with the down- and upstroke angles of attack of a wing having equal change. The constant-rate yaw rotation requires an anti-symmetrical change in the angles of attack of the contralateral wings, with the down- and upstroke angles of attack of a wing having differential change. (3) For the control of the horizontal side translation, control input required for the steady-state motion has an opposite sign to that needed for initiating the motion. For example, to have a steady-state left side-translation, the insect needs to increase the stroke amplitude of the left wing and decrease that of the right wing to maintain the steady-state flight, but it needs an opposite change in stroke amplitude (decreasing the stroke amplitude of the left wing and increasing that of the right wing) to enter the flight.

  3. Control for small-speed lateral flight in a model insect.

    Science.gov (United States)

    Zhang, Yan Lai; Sun, Mao

    2011-09-01

    Controls required for small-speed lateral flight of a model insect were studied using techniques based on the linear theories of stability and control (the stability and control derivatives were computed by the method of computational fluid dynamics). The main results are as follows. (1) Two steady-state lateral motions can exist: one is a horizontal side translation with the body rolling to the same side of the translation by a small angle, and the other is a constant-rate yaw rotation (rotation about the vertical axis). (2) The side translation requires an anti-symmetrical change in the stroke amplitudes of the contralateral wings, and/or an anti-symmetrical change in the angles of attack of the contralateral wings, with the down- and upstroke angles of attack of a wing having equal change. The constant-rate yaw rotation requires an anti-symmetrical change in the angles of attack of the contralateral wings, with the down- and upstroke angles of attack of a wing having differential change. (3) For the control of the horizontal side translation, control input required for the steady-state motion has an opposite sign to that needed for initiating the motion. For example, to have a steady-state left side-translation, the insect needs to increase the stroke amplitude of the left wing and decrease that of the right wing to maintain the steady-state flight, but it needs an opposite change in stroke amplitude (decreasing the stroke amplitude of the left wing and increasing that of the right wing) to enter the flight.

  4. Approximate analytical relationships for linear optimal aeroelastic flight control laws

    Science.gov (United States)

    Kassem, Ayman Hamdy

    1998-09-01

    This dissertation introduces new methods to uncover functional relationships between design parameters of a contemporary control design technique and the resulting closed-loop properties. Three new methods are developed for generating such relationships through analytical expressions: the Direct Eigen-Based Technique, the Order of Magnitude Technique, and the Cost Function Imbedding Technique. Efforts concentrated on the linear-quadratic state-feedback control-design technique applied to an aeroelastic flight control task. For this specific application, simple and accurate analytical expressions for the closed-loop eigenvalues and zeros in terms of basic parameters such as stability and control derivatives, structural vibration damping and natural frequency, and cost function weights are generated. These expressions explicitly indicate how the weights augment the short period and aeroelastic modes, as well as the closed-loop zeros, and by what physical mechanism. The analytical expressions are used to address topics such as damping, nonminimum phase behavior, stability, and performance with robustness considerations, and design modifications. This type of knowledge is invaluable to the flight control designer and would be more difficult to formulate when obtained from numerical-based sensitivity analysis.

  5. Impacts of safety on the design of light remotely-piloted helicopter flight control systems

    International Nuclear Information System (INIS)

    Di Rito, G.; Schettini, F.

    2016-01-01

    This paper deals with the architecture definition and the safety assessment of flight control systems for light remotely-piloted helicopters for civil applications. The methods and tools to be used for these activities are standardised for conventional piloted aircraft, while they are currently a matter of discussion in case of light remotely-piloted systems flying into unsegregated airspaces. Certification concerns are particularly problematic for aerial systems weighing from 20 to 150 kgf, since the airworthiness permission is granted by national authorities. The lack of specific requirements actually requires to analyse both the existing standards for military applications and the certification guidelines for civil systems, up to derive the adequate safety objectives. In this work, after a survey on applicable certification documents for the safety objectives definition, the most relevant functional failures of a light remotely-piloted helicopter are identified and analysed via Functional Hazard Assessment. Different architectures are then compared by means of Fault-Tree Analysis, highlighting the contributions to the safety level of the main elements of the flight control system (control computers, servoactuators, antenna) and providing basic guidelines on the required redundancy level. - Highlights: • A method for architecture definition and safety assessment of light RW‐UAS flight control systems is proposed. • Relevant UAS failures are identified and analysed via Functional Hazard Assessment and Fault‐Tree Analysis. • The key safety elements are control computers, servoactuators and TX/RX system. • Single‐simplex flight control systems have inadequate safety levels. • Dual‐duplex flight control systems demonstrate to be safety compliant, with safety budgets dominated by servoactuators.

  6. Integrated guidance and control design of a flight vehicle with side-window detection

    Directory of Open Access Journals (Sweden)

    Tianyu ZHENG

    2018-04-01

    Full Text Available This paper considers the guidance and control problem of a flight vehicle with side-window detection. In order to guarantee the target remaining in the seeker's sight of view, the line of sight and the attitude of the flight vehicle should be under some constraints caused by the side-window, which leads to coupling between the guidance and the attitude dynamics model. To deal with the side-window constraints and the coupling, a novel Integrated Guidance and Control (IGC design approach is proposed. Firstly, the relative motion equations are derived in the body-Line of Sight (LOS coordinate system. And the guidance and control problem of the flight vehicle is formulated into an IGC problem with state constraints. Then, based on the singular perturbation method, the IGC problem is decomposed into the control design of the quasi-steady-state subsystem and the boundary-layer subsystem which can be designed separately. Finally, the receding horizon control is applied to the control design for the two subsystems. Simulation results show the effectiveness of the proposed approach. Keywords: Integrated guidance and control, Receding horizon control, Side-window detection, Singular perturbation, Terminal guidance

  7. Knowledge-based processing for aircraft flight control

    Science.gov (United States)

    Painter, John H.; Glass, Emily; Economides, Gregory; Russell, Paul

    1994-01-01

    This Contractor Report documents research in Intelligent Control using knowledge-based processing in a manner dual to methods found in the classic stochastic decision, estimation, and control discipline. Such knowledge-based control has also been called Declarative, and Hybid. Software architectures were sought, employing the parallelism inherent in modern object-oriented modeling and programming. The viewpoint adopted was that Intelligent Control employs a class of domain-specific software architectures having features common over a broad variety of implementations, such as management of aircraft flight, power distribution, etc. As much attention was paid to software engineering issues as to artificial intelligence and control issues. This research considered that particular processing methods from the stochastic and knowledge-based worlds are duals, that is, similar in a broad context. They provide architectural design concepts which serve as bridges between the disparate disciplines of decision, estimation, control, and artificial intelligence. This research was applied to the control of a subsonic transport aircraft in the airport terminal area.

  8. Ares I-X Flight Test Validation of Control Design Tools in the Frequency-Domain

    Science.gov (United States)

    Johnson, Matthew; Hannan, Mike; Brandon, Jay; Derry, Stephen

    2011-01-01

    A major motivation of the Ares I-X flight test program was to Design for Data, in order to maximize the usefulness of the data recorded in support of Ares I modeling and validation of design and analysis tools. The Design for Data effort was intended to enable good post-flight characterizations of the flight control system, the vehicle structural dynamics, and also the aerodynamic characteristics of the vehicle. To extract the necessary data from the system during flight, a set of small predetermined Programmed Test Inputs (PTIs) was injected directly into the TVC signal. These PTIs were designed to excite the necessary vehicle dynamics while exhibiting a minimal impact on loads. The method is similar to common approaches in aircraft flight test programs, but with unique launch vehicle challenges due to rapidly changing states, short duration of flight, a tight flight envelope, and an inability to repeat any test. This paper documents the validation effort of the stability analysis tools to the flight data which was performed by comparing the post-flight calculated frequency response of the vehicle to the frequency response calculated by the stability analysis tools used to design and analyze the preflight models during the control design effort. The comparison between flight day frequency response and stability tool analysis for flight of the simulated vehicle shows good agreement and provides a high level of confidence in the stability analysis tools for use in any future program. This is true for both a nominal model as well as for dispersed analysis, which shows that the flight day frequency response is enveloped by the vehicle s preflight uncertainty models.

  9. Morphing flight control surface for advanced flight performance

    Science.gov (United States)

    Detrick, Matt; Kwak, Seung-Keon; Yoon, Hwan-Sik

    2006-03-01

    A novel Morphing Flight Control Surface (MFCS) system has been developed. The distinction of this research effort is that the SenAnTech team has incorporated our innovative Highly Deformable Mechanism (HDM) into our MFCS. The feasibility of this novel technology for deformable wing structures, such as airfoil shaping, warping or twisting with a flexure-based high displacement PZT actuator has been demonstrated via computational simulations such as Finite Element Analysis (FEA) and Computational Fluid Dynamics (CFD). CFD was implemented to verify the accuracy of the complex potential flow theory for this application. Then, complex potential flow theory, kinematics, geometry, and static force analysis were incorporated into a multidisciplinary GUI simulation tool. This tool has been used to aid the design of the MFCS. The results show that we can achieve up to five degrees of wing twisting with our proposed system, while using minimal volume within the wing and adding little weight.

  10. Three axis electronic flight motion simulator real time control system design and implementation.

    Science.gov (United States)

    Gao, Zhiyuan; Miao, Zhonghua; Wang, Xuyong; Wang, Xiaohua

    2014-12-01

    A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

  11. Three axis electronic flight motion simulator real time control system design and implementation

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhiyuan; Miao, Zhonghua, E-mail: zhonghua-miao@163.com; Wang, Xiaohua [School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, 200072 (China); Wang, Xuyong [School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2014-12-15

    A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

  12. Reduction of Flight Control System/Structural Mode Interaction, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel approach is proposed for reducing the degree of interaction of a high gain flight control system with the airframe structural vibration modes, representing a...

  13. Elastic Rock Heterogeneity Controls Brittle Rock Failure during Hydraulic Fracturing

    Science.gov (United States)

    Langenbruch, C.; Shapiro, S. A.

    2014-12-01

    For interpretation and inversion of microseismic data it is important to understand, which properties of the reservoir rock control the occurrence probability of brittle rock failure and associated seismicity during hydraulic stimulation. This is especially important, when inverting for key properties like permeability and fracture conductivity. Although it became accepted that seismic events are triggered by fluid flow and the resulting perturbation of the stress field in the reservoir rock, the magnitude of stress perturbations, capable of triggering failure in rocks, can be highly variable. The controlling physical mechanism of this variability is still under discussion. We compare the occurrence of microseismic events at the Cotton Valley gas field to elastic rock heterogeneity, obtained from measurements along the treatment wells. The heterogeneity is characterized by scale invariant fluctuations of elastic properties. We observe that the elastic heterogeneity of the rock formation controls the occurrence of brittle failure. In particular, we find that the density of events is increasing with the Brittleness Index (BI) of the rock, which is defined as a combination of Young's modulus and Poisson's ratio. We evaluate the physical meaning of the BI. By applying geomechanical investigations we characterize the influence of fluctuating elastic properties in rocks on the probability of brittle rock failure. Our analysis is based on the computation of stress fluctuations caused by elastic heterogeneity of rocks. We find that elastic rock heterogeneity causes stress fluctuations of significant magnitude. Moreover, the stress changes necessary to open and reactivate fractures in rocks are strongly related to fluctuations of elastic moduli. Our analysis gives a physical explanation to the observed relation between elastic heterogeneity of the rock formation and the occurrence of brittle failure during hydraulic reservoir stimulations. A crucial factor for understanding

  14. Hydraulic Theory and Hydraulic Engineering Projects of the Wusong River (吳淞江 Basin Between the Sixteenth and Nineteenth Centuries

    Directory of Open Access Journals (Sweden)

    Chulwoong Chung

    2015-02-01

    Full Text Available This paper attempts to explore the significance of the overall water control system and numerous water control projects in the Jiangnan region. Through a series of large-scale dredging projects, the Ming and Qing Dynasties attempted to achieve the goals of securing national tax revenue and guaranteeing the production activity for the farmers. However, due to the weakened hydraulic system, excessive expenses, and interests on various levels, large-scale hydraulic engineering projects were unable to achieve their original goals. Starting in the sixteenth century already, interests about practical one-time hydraulic engineering projects on a small scale began to surface. Meanwhile, in the Qing Dynasty, when the socio-economic transformation developed more, a new awareness of hydraulics surfaced due to the expansion of commercial cultivation over a large amount of land in the Jiangnan region. This was the result of an attempt to break away from the heavy dependence on water control facilities that had little room for improvement by growing a variety of plants and crops instead of focusing solely on simple grain production. Therefore the cultivation of a variety of commercial crops and plants and the development of the handicraft industry in the Jiangnan region since the sixteenth century are two aspects of Chinese society that resulted from ineffective water control facilities. However, despite these limitations and failures, large-scale hydraulic engineering projects were carried out repeatedly due to the economic importance of the Jiangnan region and to the efforts to achieve the ideals of flood control.

  15. Modeling hydraulic regenerative hybrid vehicles using AMESim and Matlab/Simulink

    Science.gov (United States)

    Lynn, Alfred; Smid, Edzko; Eshraghi, Moji; Caldwell, Niall; Woody, Dan

    2005-05-01

    This paper presents the overview of the simulation modeling of a hydraulic system with regenerative braking used to improve vehicle emissions and fuel economy. Two simulation software packages were used together to enhance the simulation capability for fuel economy results and development of vehicle and hybrid control strategy. AMESim, a hydraulic simulation software package modeled the complex hydraulic circuit and component hardware and was interlinked with a Matlab/Simulink model of the vehicle, engine and the control strategy required to operate the vehicle and the hydraulic hybrid system through various North American and European drive cycles.

  16. Development of a flight simulator for the control of plasma discharges

    Energy Technology Data Exchange (ETDEWEB)

    Ravenel, N.; Artaud, J.F.; Bremond, S.; Guillerminet, B.; Huynh, P.; Moreau, P.; Signoret, J. [CEA Cadarache, IRFM, 13 - Saint-Paul-lez-Durance (France)

    2009-07-01

    Over the years, feedback controls in fusion experiments become more and more crucial both for increasing performance, stability and ensuring machine protection. Advanced controls, such as current profile control, have to deal with nonlinear, complex physical processes that can hardly be addressed by 'trial and error' methods. Such issues highlight the necessity to build new tools based on plasma discharge flight simulator for the development, test and qualification of advanced control algorithms. A project aiming at developing such tools has started last year at Cea. A part of the project consists in the development of a flight simulator that will be integrated to the present Real Time Control and Acquisition System. Under the experimental program, it will facilitate the development and the implementation of new advanced controllers in the control units. The flight simulator will be based on the European Integrated Tokamak Modelling (ITM) simulation platform. Thus, it will benefit from the development made by the task force and it will be able to offer a development platform for the new controllers of present day European tokamaks and future machine. This paper will address the architecture of the project focussing on the following items: -) Development of a 'high level' interface to build plasma scenarios as a set in sequence; -) Interface of the Tore Supra data and parameters within the ITM data structure; -) Integration of the developments under the ITM simulation platform (Kepler) using Xcos software (produced by the Scilab Consortium) functionalities such as the automatic code generation for the implementation of the controllers; -) Modification of the present control unit software towards modular units in order to facilitate control algorithm development. This document is composed of an abstract followed by the presentation transparencies. (authors)

  17. Design Specification for a Thrust-Vectoring, Actuated-Nose-Strake Flight Control Law for the High-Alpha Research Vehicle

    Science.gov (United States)

    Bacon, Barton J.; Carzoo, Susan W.; Davidson, John B.; Hoffler, Keith D.; Lallman, Frederick J.; Messina, Michael D.; Murphy, Patrick C.; Ostroff, Aaron J.; Proffitt, Melissa S.; Yeager, Jessie C.; hide

    1996-01-01

    Specifications for a flight control law are delineated in sufficient detail to support coding the control law in flight software. This control law was designed for implementation and flight test on the High-Alpha Research Vehicle (HARV), which is an F/A-18 aircraft modified to include an experimental multi-axis thrust-vectoring system and actuated nose strakes for enhanced rolling (ANSER). The control law, known as the HARV ANSER Control Law, was designed to utilize a blend of conventional aerodynamic control effectors, thrust vectoring, and actuated nose strakes to provide increased agility and good handling qualities throughout the HARV flight envelope, including angles of attack up to 70 degrees.

  18. Turbulent Motion of Liquids in Hydraulic Resistances with a Linear Cylindrical Slide-Valve

    Directory of Open Access Journals (Sweden)

    C. Velescu

    2015-01-01

    Full Text Available We analyze the motion of viscous and incompressible liquids in the annular space of controllable hydraulic resistances with a cylindrical linear slide-valve. This theoretical study focuses on the turbulent and steady-state motion regimes. The hydraulic resistances mentioned above are the most frequent type of hydraulic resistances used in hydraulic actuators and automation systems. To study the liquids’ motion in the controllable hydraulic resistances with a linear cylindrical slide-valve, the report proposes an original analytic method. This study can similarly be applied to any other type of hydraulic resistance. Another purpose of this study is to determine certain mathematical relationships useful to approach the theoretical functionality of hydraulic resistances with magnetic controllable fluids as incompressible fluids in the presence of a controllable magnetic field. In this report, we established general analytic equations to calculate (i velocity and pressure distributions, (ii average velocity, (iii volume flow rate of the liquid, (iv pressures difference, and (v radial clearance.

  19. Subscale Flight Testing for Aircraft Loss of Control: Accomplishments and Future Directions

    Science.gov (United States)

    Cox, David E.; Cunningham, Kevin; Jordan, Thomas L.

    2012-01-01

    Subscale flight-testing provides a means to validate both dynamic models and mitigation technologies in the high-risk flight conditions associated with aircraft loss of control. The Airborne Subscale Transport Aircraft Research (AirSTAR) facility was designed to be a flexible and efficient research facility to address this type of flight-testing. Over the last several years (2009-2011) it has been used to perform 58 research flights with an unmanned, remotely-piloted, dynamically-scaled airplane. This paper will present an overview of the facility and its architecture and summarize the experimental data collected. All flights to date have been conducted within visual range of a safety observer. Current plans for the facility include expanding the test volume to altitudes and distances well beyond visual range. The architecture and instrumentation changes associated with this upgrade will also be presented.

  20. Several new thermo-hydraulic test facilities in NPIC

    International Nuclear Information System (INIS)

    Ye Shurong; Sun Yufa; Ji Fuyun; Zong Guifang; Guo Zhongchuan

    1997-01-01

    Several new thermo-hydraulic test facilities are under construction in Nuclear Power Institute of Chinese (NPIC) at Chengdu. These facilities include: 1. Nuclear Power Component Comprehensive Test Facility. 2. Reactor Hydraulic Modeling Test Facility. 3. Control Rod Drive Line Hydraulic Test Facility. 4. Large Scale Thermo-Hydraulic Test Facility. The construction of these facilities will make huge progress in the research and development capability of nuclear power technology in CHINA. The author will present a brief description of the design parameters flowchart and test program of these facilities

  1. Nonlinear Robust Control of a Hypersonic Flight Vehicle Using Fuzzy Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Lei Zhengdong

    2013-01-01

    Full Text Available This paper is concerned with a novel tracking controller design for a hypersonic flight vehicle in complex and volatile environment. The attitude control model is challengingly constructed with multivariate uncertainties and external disturbances, such as structure dynamic and stochastic wind disturbance. In order to resist the influence of uncertainties and disturbances on the flight control system, nonlinear disturbance observer is introduced to estimate them. Moreover, for the sake of high accuracy and sensitivity, fuzzy theory is adopted to improve the performance of the nonlinear disturbance observer. After the total disturbance is eliminated by dynamic inversion method, a cascade system is obtained and then stabilized by a sliding-mode controller. Finally, simulation results show that the strong robust controller achieves excellent performance when the closed-loop control system is influenced by mass uncertainties and external disturbances.

  2. Control strategy of hydraulic/electric synergy system in heavy hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Sun Hui; Yang Lifu; Junqing Jing; Yanling Luo [Jiangsu Xuzhou Construction Machinery Research Institute, Jiangsu (China)

    2011-01-15

    Energy consumption and exhaust emissions of hybrid vehicles strongly depend on the energy storage source and the applied control strategy. Heavy vehicles have the characteristics of frequent starts/stops and significant amounts of braking energy, which needs to find a more efficient way to store and use the high power flow. A novel parallel hybrid vehicles configuration consisting of hydraulic/electric synergy system is proposed to overcome the existing drawbacks of single energy storage source in heavy hybrid vehicles. A control strategy combining a logic threshold approach and key parameters optimization algorithm is developed to achieve acceptable vehicle performance while simultaneously maximizing engine fuel economy and maintaining the battery state of charge in its rational operation range at all times. The experimental and simulation results illustrate the potential of the proposed control strategy in terms of fuel economy and in keeping the deviations of SOC at high efficiency range. (author)

  3. Control strategy of hydraulic/electric synergy system in heavy hybrid vehicles

    International Nuclear Information System (INIS)

    Sun Hui; Yang Lifu; Jing Junqing; Luo Yanling

    2011-01-01

    Energy consumption and exhaust emissions of hybrid vehicles strongly depend on the energy storage source and the applied control strategy. Heavy vehicles have the characteristics of frequent starts/stops and significant amounts of braking energy, which needs to find a more efficient way to store and use the high power flow. A novel parallel hybrid vehicles configuration consisting of hydraulic/electric synergy system is proposed to overcome the existing drawbacks of single energy storage source in heavy hybrid vehicles. A control strategy combining a logic threshold approach and key parameters optimization algorithm is developed to achieve acceptable vehicle performance while simultaneously maximizing engine fuel economy and maintaining the battery state of charge in its rational operation range at all times. The experimental and simulation results illustrate the potential of the proposed control strategy in terms of fuel economy and in keeping the deviations of SOC at high efficiency range.

  4. Design of passive fault-tolerant flight controller against actuator failures

    Directory of Open Access Journals (Sweden)

    Xiang Yu

    2015-02-01

    Full Text Available The problem of designing passive fault-tolerant flight controller is addressed when the normal and faulty cases are prescribed. First of all, the considered fault and fault-free cases are formed by polytopes. As considering that the safety of a post-fault system is directly related to the maximum values of physical variables in the system, peak-to-peak gain is selected to represent the relationships among the amplitudes of actuator outputs, system outputs, and reference commands. Based on the parameter dependent Lyapunov and slack methods, the passive fault-tolerant flight controllers in the absence/presence of system uncertainty for actuator failure cases are designed, respectively. Case studies of an airplane under actuator failures are carried out to validate the effectiveness of the proposed approach.

  5. NASA flight controllers - Meeting cultural and leadership challenges on the critical path to mission success

    Science.gov (United States)

    Clement, James L., Jr.; Ritsher, Jennifer Boyd

    2006-01-01

    As part of its preparation for missions to the Moon and Mars, NASA has identified high priority critical path roadmap (CPR) questions, two of which focus on the performance of mission control personnel. NASA flight controllers have always worked in an incredibly demanding setting, but the International Space Station poses even more challenges than prior missions. We surveyed 14 senior ISS flight controllers and a contrasting sample of 12 more junior controllers about the management and cultural challenges they face and the most effective strategies for addressing them. There was substantial consensus among participants on some issues, such as the importance of building a personal relationship with Russian colleagues. Responses from junior and senior controllers differed in some areas, such as training. We frame the results in terms of two CPR questions. We aim to use our results to improve flight controller training.

  6. Global asymptotic stabilization of large-scale hydraulic networks using positive proportional controls

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard; Wisniewski, Rafal

    2014-01-01

    An industrial case study involving a large-scale hydraulic network underlying a district heating system subject to structural changes is considered. The problem of controlling the pressure drop across the so-called end-user valves in the network to a designated vector of reference values under...... directional actuator constraints is addressed. The proposed solution consists of a set of decentralized positively constrained proportional control actions. The results show that the closed-loop system always has a globally asymptotically stable equilibrium point independently on the number of end......-users. Furthermore, by a proper design of controller gains the closed-loop equilibrium point can be designed to belong to an arbitrarily small neighborhood of the desired equilibrium point. Since there exists a globally asymptotically stable equilibrium point independently on the number of end-users in the system...

  7. Multi-Objective Flight Control for Drag Minimization and Load Alleviation of High-Aspect Ratio Flexible Wing Aircraft

    Science.gov (United States)

    Nguyen, Nhan; Ting, Eric; Chaparro, Daniel; Drew, Michael; Swei, Sean

    2017-01-01

    As aircraft wings become much more flexible due to the use of light-weight composites material, adverse aerodynamics at off-design performance can result from changes in wing shapes due to aeroelastic deflections. Increased drag, hence increased fuel burn, is a potential consequence. Without means for aeroelastic compensation, the benefit of weight reduction from the use of light-weight material could be offset by less optimal aerodynamic performance at off-design flight conditions. Performance Adaptive Aeroelastic Wing (PAAW) technology can potentially address these technical challenges for future flexible wing transports. PAAW technology leverages multi-disciplinary solutions to maximize the aerodynamic performance payoff of future adaptive wing design, while addressing simultaneously operational constraints that can prevent the optimal aerodynamic performance from being realized. These operational constraints include reduced flutter margins, increased airframe responses to gust and maneuver loads, pilot handling qualities, and ride qualities. All of these constraints while seeking the optimal aerodynamic performance present themselves as a multi-objective flight control problem. The paper presents a multi-objective flight control approach based on a drag-cognizant optimal control method. A concept of virtual control, which was previously introduced, is implemented to address the pair-wise flap motion constraints imposed by the elastomer material. This method is shown to be able to satisfy the constraints. Real-time drag minimization control is considered to be an important consideration for PAAW technology. Drag minimization control has many technical challenges such as sensing and control. An initial outline of a real-time drag minimization control has already been developed and will be further investigated in the future. A simulation study of a multi-objective flight control for a flight path angle command with aeroelastic mode suppression and drag

  8. A passion for space adventures of a pioneering female NASA flight controller

    CERN Document Server

    Dyson, Marianne J

    2016-01-01

    Marianne J. Dyson recounts for us a time when women were making the first inroads into space flight control, a previously male-dominated profession. The story begins with the inspiration of the Apollo 11 landing on the Moon and follows the challenges of pursuing a science career as a woman in the 70s and 80s, when it was far from an easy path.  Dyson relates the first five space shuttle flights from the personal perspective of mission planning and operations in Houston at the Johnson Space Center, based almost exclusively on original sources such as journals and NASA weekly activity reports. The book’s historical details about astronaut and flight controller training exemplify both the humorous and serious aspects of space operations up through the Challenger disaster, including the almost unknown fire in Mission Control during STS-5 that nearly caused an emergency entry of the shuttle.  From an insider with a unique perspective and credentials to match, this a must-read for anyone interested in the worki...

  9. Real-Time Reliability Verification for UAV Flight Control System Supporting Airworthiness Certification.

    Science.gov (United States)

    Xu, Haiyang; Wang, Ping

    2016-01-01

    In order to verify the real-time reliability of unmanned aerial vehicle (UAV) flight control system and comply with the airworthiness certification standard, we proposed a model-based integration framework for modeling and verification of time property. Combining with the advantages of MARTE, this framework uses class diagram to create the static model of software system, and utilizes state chart to create the dynamic model. In term of the defined transformation rules, the MARTE model could be transformed to formal integrated model, and the different part of the model could also be verified by using existing formal tools. For the real-time specifications of software system, we also proposed a generating algorithm for temporal logic formula, which could automatically extract real-time property from time-sensitive live sequence chart (TLSC). Finally, we modeled the simplified flight control system of UAV to check its real-time property. The results showed that the framework could be used to create the system model, as well as precisely analyze and verify the real-time reliability of UAV flight control system.

  10. EVA Wiki - Transforming Knowledge Management for EVA Flight Controllers and Instructors

    Science.gov (United States)

    Johnston, Stephanie S.; Alpert, Brian K.; Montalvo, Edwin James; Welsh, Lawrence Daren; Wray, Scott; Mavridis, Costa

    2016-01-01

    The EVA Wiki was recently implemented as the primary knowledge database to retain critical knowledge and skills in the EVA Operations group at NASA's Johnson Space Center by ensuring that information is recorded in a common, easy to search repository. Prior to the EVA Wiki, information required for EVA flight controllers and instructors was scattered across different sources, including multiple file share directories, SharePoint, individual computers, and paper archives. Many documents were outdated, and data was often difficult to find and distribute. In 2011, a team recognized that these knowledge management problems could be solved by creating an EVA Wiki using MediaWiki, a free and open-source software developed by the Wikimedia Foundation. The EVA Wiki developed into an EVA-specific Wikipedia on an internal NASA server. While the technical implementation of the wiki had many challenges, one of the biggest hurdles came from a cultural shift. Like many enterprise organizations, the EVA Operations group was accustomed to hierarchical data structures and individually-owned documents. Instead of sorting files into various folders, the wiki searches content. Rather than having a single document owner, the wiki harmonized the efforts of many contributors and established an automated revision controlled system. As the group adapted to the wiki, the usefulness of this single portal for information became apparent. It transformed into a useful data mining tool for EVA flight controllers and instructors, as well as hundreds of others that support EVA. Program managers, engineers, astronauts, flight directors, and flight controllers in differing disciplines now have an easier-to-use, searchable system to find EVA data. This paper presents the benefits the EVA Wiki has brought to NASA's EVA community, as well as the cultural challenges it had to overcome.

  11. EVA Wiki - Transforming Knowledge Management for EVA Flight Controllers and Instructors

    Science.gov (United States)

    Johnston, Stephanie

    2016-01-01

    The EVA (Extravehicular Activity) Wiki was recently implemented as the primary knowledge database to retain critical knowledge and skills in the EVA Operations group at NASA's Johnson Space Center by ensuring that information is recorded in a common, searchable repository. Prior to the EVA Wiki, information required for EVA flight controllers and instructors was scattered across different sources, including multiple file share directories, SharePoint, individual computers, and paper archives. Many documents were outdated, and data was often difficult to find and distribute. In 2011, a team recognized that these knowledge management problems could be solved by creating an EVA Wiki using MediaWiki, a free and open-source software developed by the Wikimedia Foundation. The EVA Wiki developed into an EVA-specific Wikipedia on an internal NASA server. While the technical implementation of the wiki had many challenges, the one of the biggest hurdles came from a cultural shift. Like many enterprise organizations, the EVA Operations group was accustomed to hierarchical data structures and individually-owned documents. Instead of sorting files into various folders, the wiki searches content. Rather than having a single document owner, the wiki harmonized the efforts of many contributors and established an automated revision control system. As the group adapted to the wiki, the usefulness of this single portal for information became apparent. It transformed into a useful data mining tool for EVA flight controllers and instructors, and also for hundreds of other NASA and contract employees. Program managers, engineers, astronauts, flight directors, and flight controllers in differing disciplines now have an easier-to-use, searchable system to find EVA data. This paper presents the benefits the EVA Wiki has brought to NASA's EVA community, as well as the cultural challenges it had to overcome.

  12. Extended Analytic Linear Model of Hydraulic Cylinder With Respect Different Piston Areas and Volumes

    Directory of Open Access Journals (Sweden)

    Petr KOŇAŘÍK

    2009-06-01

    Full Text Available Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cylinder. Presented paper deal with development of extended form of analytic linear model of single piston rod hydraulic cylinder which respects different action piston areas and volumes inside of chambers of hydraulic cylinder and also two different input flows of hydraulic cylinder. In extended model are also considered possibilities of different dead volumes in hoses and intake parts of hydraulic cylinder. Dead volume has impact on damping of hydraulic cylinder. Because the system of hydraulic cylinder is generally presented as a integrative system with inertia of second order: eq , we can than obtain time constants and damping of hydraulic cylinder for each of analytic form model. The model has arisen for needs of model fractionation on two parts. Part of behaviour of chamber A and part of behaviour of chamber B of cylinder. It was created for the reason of analysis and synthesis of control parameters of regulation circuit of multivalve control concept of hydraulic drive with separately controlled chamber A and B which could be then used for.

  13. Use of Plant Hydraulic Theory to Predict Ecosystem Fluxes Across Mountainous Gradients in Environmental Controls and Insect Disturbances

    Science.gov (United States)

    Ewers, B. E.; Pendall, E.; Reed, D. E.; Barnard, H. R.; Whitehouse, F.; Frank, J. M.; Massman, W. J.; Brooks, P. D.; Biederman, J. A.; Harpold, A. A.; Naithani, K. J.; Mitra, B.; Mackay, D. S.; Norton, U.; Borkhuu, B.

    2011-12-01

    While mountainous areas are critical for providing numerous ecosystem benefits at the regional scale, the strong gradients in environmental controls make predictions difficult. A key part of the problem is quantifying and predicting the feedback between mountain gradients and plant function which then controls ecosystem cycling. The emerging theory of plant hydraulics provides a rigorous yet simple platform from which to generate testable hypotheses and predictions of ecosystem pools and fluxes. Plant hydraulic theory predicts that plant controls over carbon, water, energy and nutrient fluxes can be derived from the limitation of plant water transport from the soil through xylem and out of stomata. In addition, the limit to plant water transport can be predicted by combining plant structure (e.g. xylem diameters or root-to-shoot ratios) and plant function (response of stomatal conductance to vapor pressure deficit or root vulnerability to cavitation). We evaluate the predictions of the plant hydraulic theory by testing it against data from a mountain gradient encompassing sagebrush steppe through subalpine forests (2700 to 3400 m). We further test the theory by predicting the carbon, water and nutrient exchanges from several coniferous trees in the same gradient that are dying from xylem dysfunction caused by blue-stain fungi carried by bark beetles. The common theme of both of these data sets is a change in water limitation caused by either changing precipitation along the mountainous gradient or lack of access to soil water from xylem-occluding fungi. Across all of the data sets which range in scale from individual plants to hillslopes, the data fit the predictions of plant hydraulic theory. Namely, there was a proportional tradeoff between the reference canopy stomatal conductance to water vapor and the sensitivity of that conductance to vapor pressure deficit that quantitatively fits the predictions of plant hydraulic theory. Incorporating this result into

  14. Neuroinspired control strategies with applications to flapping flight

    Science.gov (United States)

    Dorothy, Michael Ray

    This dissertation is centered on a theoretical, simulation, and experimental study of control strategies which are inspired by biological systems. Biological systems, along with sufficiently complicated engineered systems, often have many interacting degrees of freedom and need to excite large-displacement oscillations in order to locomote. Combining these factors can make high-level control design difficult. This thesis revolves around three different levels of abstraction, providing tools for analysis and design. First, we consider central pattern generators (CPGs) to control flapping-flight dynamics. The key idea here is dimensional reduction - we want to convert complicated interactions of many degrees of freedom into a handful of parameters which have intuitive connections to the overall system behavior, leaving the control designer unconcerned with the details of particular motions. A rigorous mathematical and control theoretic framework to design complex three-dimensional wing motions is presented based on phase synchronization of nonlinear oscillators. In particular, we show that flapping-flying dynamics without a tail or traditional aerodynamic control surfaces can be effectively controlled by a reduced set of central pattern generator parameters that generate phase-synchronized or symmetry-breaking oscillatory motions of two main wings. Furthermore, by using a Hopf bifurcation, we show that tailless aircraft (inspired by bats) alternating between flapping and gliding can be effectively stabilized by smooth wing motions driven by the central pattern generator network. Results of numerical simulation with a full six-degree-of-freedom flight dynamic model validate the effectiveness of the proposed neurobiologically inspired control approach. Further, we present experimental micro aerial vehicle (MAV) research with low-frequency flapping and articulated wing gliding. The importance of phase difference control via an abstract mathematical model of central

  15. Multi-Vehicle Cooperative Control Research at the NASA Armstrong Flight Research Center, 2000-2014

    Science.gov (United States)

    Hanson, Curt

    2014-01-01

    A brief introductory overview of multi-vehicle cooperative control research conducted at the NASA Armstrong Flight Research Center from 2000 - 2014. Both flight research projects and paper studies are included. Since 2000, AFRC has been almost continuously pursuing research in the areas of formation flight for drag reduction and automated cooperative trajectories. An overview of results is given, including flight experiments done on the FA-18 and with the C-17. Other multi-vehicle cooperative research is discussed, including small UAV swarming projects and automated aerial refueling.

  16. In-Flight Suppression of an Unstable F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

    Science.gov (United States)

    VanZwieten, Tannen S.; Gilligan, Eric T.; Wall, John H.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

    2015-01-01

    NASA's Space Launch System (SLS) Flight Control System (FCS) includes an Adaptive Augmenting Control (AAC) component which employs a multiplicative gain update law to enhance the performance and robustness of the baseline control system for extreme off-nominal scenarios. The SLS FCS algorithm including AAC has been flight tested utilizing a specially outfitted F/A-18 fighter jet in which the pitch axis control of the aircraft was performed by a Non-linear Dynamic Inversion (NDI) controller, SLS reference models, and the SLS flight software prototype. This paper describes test cases from the research flight campaign in which the fundamental F/A-18 airframe structural mode was identified using post-flight frequency-domain reconstruction, amplified to result in closed loop instability, and suppressed in-flight by the SLS adaptive control system.

  17. In-Flight Suppression of a Destabilized F/A-18 Structural Mode Using the Space Launch System Adaptive Augmenting Control System

    Science.gov (United States)

    Wall, John H.; VanZwieten, Tannen S.; Gilligan, Eric T.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

    2015-01-01

    NASA's Space Launch System (SLS) Flight Control System (FCS) includes an Adaptive Augmenting Control (AAC) component which employs a multiplicative gain update law to enhance the performance and robustness of the baseline control system for extreme off nominal scenarios. The SLS FCS algorithm including AAC has been flight tested utilizing a specially outfitted F/A-18 fighter jet in which the pitch axis control of the aircraft was performed by a Non-linear Dynamic Inversion (NDI) controller, SLS reference models, and the SLS flight software prototype. This paper describes test cases from the research flight campaign in which the fundamental F/A-18 airframe structural mode was identified using frequency-domain reconstruction of flight data, amplified to result in closed loop instability, and suppressed in-flight by the SLS adaptive control system.

  18. Trends in hydraulics laboratory research in the Netherlands

    NARCIS (Netherlands)

    Van de Wel, J.; Prins, J.E.; De Vries, M.; Paape, A.; Abraham, G.; Hoekstra, A.J.; Wijdieks, J.; Diephuis, J.G.H.R.; Reinalda, R.; Bijker, E.W.; Schoemaker, H.J.

    1963-01-01

    Scope and aims in model techniques, instrumental aids for hydraulic model studies,investigations of structures for flow control, river studies, model investigations on local scour, problems connected with flows due to differences in density, from Spaarndam to Veersche Gat, hydraulic refinement of

  19. Flight mechanics and control of escape manoeuvres in hummingbirds. I. Flight kinematics.

    Science.gov (United States)

    Cheng, Bo; Tobalske, Bret W; Powers, Donald R; Hedrick, Tyson L; Wethington, Susan M; Chiu, George T C; Deng, Xinyan

    2016-11-15

    Hummingbirds are nature's masters of aerobatic manoeuvres. Previous research shows that hummingbirds and insects converged evolutionarily upon similar aerodynamic mechanisms and kinematics in hovering. Herein, we use three-dimensional kinematic data to begin to test for similar convergence of kinematics used for escape flight and to explore the effects of body size upon manoeuvring. We studied four hummingbird species in North America including two large species (magnificent hummingbird, Eugenes fulgens, 7.8 g, and blue-throated hummingbird, Lampornis clemenciae, 8.0 g) and two smaller species (broad-billed hummingbird, Cynanthus latirostris, 3.4 g, and black-chinned hummingbirds Archilochus alexandri, 3.1 g). Starting from a steady hover, hummingbirds consistently manoeuvred away from perceived threats using a drastic escape response that featured body pitch and roll rotations coupled with a large linear acceleration. Hummingbirds changed their flapping frequency and wing trajectory in all three degrees of freedom on a stroke-by-stroke basis, likely causing rapid and significant alteration of the magnitude and direction of aerodynamic forces. Thus it appears that the flight control of hummingbirds does not obey the 'helicopter model' that is valid for similar escape manoeuvres in fruit flies. Except for broad-billed hummingbirds, the hummingbirds had faster reaction times than those reported for visual feedback control in insects. The two larger hummingbird species performed pitch rotations and global-yaw turns with considerably larger magnitude than the smaller species, but roll rates and cumulative roll angles were similar among the four species. © 2016. Published by The Company of Biologists Ltd.

  20. Hydraulic structures

    CERN Document Server

    Chen, Sheng-Hong

    2015-01-01

    This book discusses in detail the planning, design, construction and management of hydraulic structures, covering dams, spillways, tunnels, cut slopes, sluices, water intake and measuring works, ship locks and lifts, as well as fish ways. Particular attention is paid to considerations concerning the environment, hydrology, geology and materials etc. in the planning and design of hydraulic projects. It also considers the type selection, profile configuration, stress/stability calibration and engineering countermeasures, flood releasing arrangements and scouring protection, operation and maintenance etc. for a variety of specific hydraulic structures. The book is primarily intended for engineers, undergraduate and graduate students in the field of civil and hydraulic engineering who are faced with the challenges of extending our understanding of hydraulic structures ranging from traditional to groundbreaking, as well as designing, constructing and managing safe, durable hydraulic structures that are economical ...

  1. Hydraulic considerations in deigning an oil spill control system for stormwater outfall

    Energy Technology Data Exchange (ETDEWEB)

    Li, J.; Chui, J. [Ryerson University, Dept. of Civil Engineering, Toronto, ON (Canada)

    2004-09-01

    An oil spill control system, consisting of an on-line triangular lateral diversion channel and an off-line tilted-plate oil-water separator, installed in the Humber Creek sub-watershed in Toronto, Ontario, is described. The area, which rims the shore of Lake Ontario from the Niagara Peninsula to Oshawa, is heavily industrialized, and is home to some 5.6 million people. During the 1990s an estimated average of 1050 litre/day of petroleum products have escaped into the environment; soil contamination occurred in 55 per cent of the cases, and water-course pollution in 31 per cent. A physical model study was conducted at the National Water Research Institute's Hydraulic Laboratory in Burlington, Ontario, to investigate the hydraulic behaviour of the spill control system under different flow conditions. Results of the investigation confirmed the design conveyance capacity of the lateral diversion channel; it also confirmed that floating objects and settleable solids could be trapped inside the oil-water separator under various flow conditions. Because the angled diversion channel was observed to cause a vortex action inside the first and second chambers of the separator and increase the potential for trapped oil to be flushed out, it is recommended that the final design of the spill control system pay special attention to the vortex problem. One potential solution for this problem may be the installation of baffles at the second chamber of the oil-water separator. It was further recommended that the design should also address the flushing of trapped oil during wet weather conditions. 23 refs., 2 tabs., 10 figs.

  2. Flight Test Comparison of Different Adaptive Augmentations for Fault Tolerant Control Laws for a Modified F-15 Aircraft

    Science.gov (United States)

    Burken, John J.; Hanson, Curtis E.; Lee, James A.; Kaneshige, John T.

    2009-01-01

    This report describes the improvements and enhancements to a neural network based approach for directly adapting to aerodynamic changes resulting from damage or failures. This research is a follow-on effort to flight tests performed on the NASA F-15 aircraft as part of the Intelligent Flight Control System research effort. Previous flight test results demonstrated the potential for performance improvement under destabilizing damage conditions. Little or no improvement was provided under simulated control surface failures, however, and the adaptive system was prone to pilot-induced oscillations. An improved controller was designed to reduce the occurrence of pilot-induced oscillations and increase robustness to failures in general. This report presents an analysis of the neural networks used in the previous flight test, the improved adaptive controller, and the baseline case with no adaptation. Flight test results demonstrate significant improvement in performance by using the new adaptive controller compared with the previous adaptive system and the baseline system for control surface failures.

  3. Effect of the method of photomultiplier gain control on electron time-of-flight in FEhU-30

    International Nuclear Information System (INIS)

    Gladyshev, D.A.; Li, B.N.

    1979-01-01

    The effect of a method of control of the multiplication factor of a photomultiplier on the electron flight time has been investigated. Presented are the results of measuring the dependence of the electron flight time for the following methods of stabilizing the photomultiplier multiplication: adjustment of multiplication by changing the supply voltage; control of multiplication with the help of a resistor which shunts two neighbouring interdynode gaps, and the control of the multiplication factor by changing a magnetic field caused due to changes in the current flowing through a special solenoid. It has been found that in these methods changes in the flight time constituted 260 and 140 ns. Magnetic-field control does not affect the flight time with an accuracy of up to 20 ps

  4. Wind tunnel experiments to prove a hydraulic passive torque control concept for variable speed wind turbines

    NARCIS (Netherlands)

    Diepeveen, N.F.B.; Jarquin-Laguna, A.

    2014-01-01

    In this paper the results are presented of experiments to prove an innovative concept for passive torque control of variable speed wind turbines using fluid power technology. It is demonstrated that by correctly configuring the hydraulic drive train, the wind turbine rotor operates at or near

  5. Hydraulic shock absorbers

    International Nuclear Information System (INIS)

    Thatcher, G.; Davidson, D. F.

    1984-01-01

    A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods

  6. Development of a Model Following Control Law for Inflight Simulation and Flight Controls Research

    Science.gov (United States)

    Takahashi, Mark; Fletcher, Jay; Aiken, Edwin W. (Technical Monitor)

    1994-01-01

    The U.S. Army and NASA are currently developing the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) at the Ames Research Center. RASCAL, shown in Figure 1, is a UH-60, which is being modified in a phased development program to have a research fly-by-wire flight control system, and an advanced navigation research platform. An important part of the flight controls and handling qualities research on RASCAL will be an FCS design for the aircraft to achieve high bandwidth control responses and disturbance rejection characteristics. Initially, body states will be used as feedbacks, but research into the use of rotor states will also be considered in later stages to maximize agility and maneuverability. In addition to supporting flight controls research, this FCS design will serve as the inflight simulation control law to support basic handling qualities, guidance, and displays research. Research in high bandwidth controls laws is motivated by the desire to improve the handling qualities in aggressive maneuvering and in severely degraded weather conditions. Naturally, these advantages will also improve the quality of the model following, thereby improving the inflight simulation capabilities of the research vehicle. High bandwidth in the control laws provides tighter tracking allowing for higher response bandwidths which can meet handling qualities requirements for aggressive maneuvering. System sensitivity is also reduced preventing variations in the response from the vehicle due to changing flight conditions. In addition, improved gust rejection will result from this reduced sensitivity. The gust rejection coupled with a highly stable system will make more precise maneuvering and pointing possible in severely degraded weather conditions. The difficulty in achieving higher bandwidths from the control laws in the feedback and in the responses arises from the complexity of the models that are needed to produce a satisfactory design. In this case, high

  7. Hydraulic Pump Fault Diagnosis Control Research Based on PARD-BP Algorithm

    Directory of Open Access Journals (Sweden)

    LV Dongmei

    2014-12-01

    Full Text Available Combining working principle and failure mechanism of RZU2000HM hydraulic press, with its present fault cases being collected, the working principle of the oil pressure and faults phenomenon of the hydraulic power unit –swash-plate axial piston pump were studied with some emphasis, whose faults will directly affect the dynamic performance of the oil pressure and flow. In order to make hydraulic power unit work reliably, PARD-BP (Pruning Algorithm based Random Degree neural network fault algorithm was introduced, with swash-plate axial piston pump’s vibration fault sample data regarded as input, and fault mode matrix regarded as target output, so that PARD-BP algorithm could be trained. In the end, the vibration results were verified by the vibration modal test, and it was shown that the biggest upward peaks of vacuum pump in X-direction, Y-direction and Z- direction have fallen by 30.49 %, 21.13 % and 18.73 % respectively, so that the reliability of the fact that PARD-BP algorithm could be used for the online fault detection and diagnosis of the hydraulic pump was verified.

  8. CRAB-II: a computer program to predict hydraulics and scram dynamics of LMFBR control assemblies and its validation

    International Nuclear Information System (INIS)

    Carelli, M.D.; Baker, L.A.; Willis, J.M.; Engel, F.C.; Nee, D.Y.

    1982-01-01

    This paper presents an analytical method, the computer code CRAB-II, which calculates the hydraulics and scram dynamics of LMFBR control assemblies of the rod bundle type and its validation against prototypic data obtained for the Clinch River Breeder Reactor (CRBR) primary control assemblies. The physical-mathematical model of the code is presented, followed by a description of the testing of prototypic CRBR control assemblies in water and sodium to characterize, respectively, their hydraulic and scram dynamics behavior. Comparison of code predictions against the experimental data are presened in detail; excellent agreement was found. Also reported are experimental data and empirical correlations for the friction factor of the absorber bundle in the entire flow range (laminar to turbulent) which represent an extension of the state-of-the-art, since only fuel and blanket assemblies friction factor correlations were previously reported in the open literature

  9. Intelligent Hydraulic Actuator and Exp-based Modelling of Losses in Pumps and .

    DEFF Research Database (Denmark)

    Zhang, Muzhi

    A intelligent fuzzy logic self-organising PD+I controller for a gearrotor hydraulic motor was developed and evaluated. Furthermore, a experimental-based modelling methods with a new software tool 'Dynamodata' for modelling of losses in hydraulic motors and pumps was developed.......A intelligent fuzzy logic self-organising PD+I controller for a gearrotor hydraulic motor was developed and evaluated. Furthermore, a experimental-based modelling methods with a new software tool 'Dynamodata' for modelling of losses in hydraulic motors and pumps was developed....

  10. 78 FR 11554 - Special Conditions: Embraer S.A., Model EMB-550 Airplane, Limit Pilot Forces for Sidestick Control

    Science.gov (United States)

    2013-02-19

    ... approximately 6,540 pounds of thrust for normal takeoff. The primary flight controls consist of hydraulically... FAA must issue a finding of regulatory adequacy under section 611 of Public Law 92-574, the ``Noise Control Act of 1972.'' The FAA issues special conditions, as defined in 14 CFR 11.19, in accordance with...

  11. A switched energy saving position controller for variable-pressure electro-hydraulic servo systems.

    Science.gov (United States)

    Tivay, Ali; Zareinejad, Mohammad; Rezaei, S Mehdi; Baghestan, Keivan

    2014-07-01

    The electro-hydraulic servo system (EHSS) demonstrates a relatively low level of efficiency compared to other available actuation methods. The objective of this paper is to increase this efficiency by introducing a variable supply pressure into the system and controlling this pressure during the task of position tracking. For this purpose, an EHSS structure with controllable supply pressure is proposed and its dynamic model is derived from the basic laws of physics. A switching control structure is then proposed to control both the supply pressure and the cylinder position at the same time, in a way that reduces the overall energy consumption of the system. The stability of the proposed switching control system is guaranteed by proof, and its performance is verified by experimental testing. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  12. Education for hydraulics and pneumatics in Nihon University; Nihon Daigaku ni okeru yukuatsu kyoiku

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, M. [Nihon Univ., Chiba (Japan). Coll. of Industrial Technology

    2000-03-15

    Described herein is education of hydraulics and pneumatics in Nihon University. Department of Mechanical Engineering of Faculty of Production Engineering has been holding up the educational aims of bringing up engineers and researchers who have ability and intelligence to cope with internationalization and contribute to society, and of bringing about creativity, among others. Control equipment is an optional subject for the sophomore class in the second semester, and is centered by mechatronics, including hydraulic and pneumatic control systems and equipment. The related subjects include fluid dynamics, control engineering, system controlling, hydraulic machines, robotics and automobile engineering. The drill course includes disassembling and assembling gear pumps, drills on pneumatic devices, system behavior and mechatronics, experiments on fan and hydraulic control circuits and on servo mechanisms, and machinery designs and drawings. Seminars are led by full-time or part-time lecturers for the themes related to hydraulic power. Many students are interested in hydraulic and pneumatic themes for their graduation theses, because of their relations with control, environments, energy saving and so on. We are now in the age of composite technologies, and hydraulic power basics are prerequisite for engineers, and important for education of students. (NEDO)

  13. Design, analysis and control of large transports so that control of engine thrust can be used as a back-up of the primary flight controls. Ph.D. Thesis

    Science.gov (United States)

    Roskam, Jan; Ackers, Deane E.; Gerren, Donna S.

    1995-01-01

    A propulsion controlled aircraft (PCA) system has been developed at NASA Dryden Flight Research Center at Edwards Air Force Base, California, to provide safe, emergency landing capability should the primary flight control system of the aircraft fail. As a result of the successful PCA work being done at NASA Dryden, this project investigated the possibility of incorporating the PCA system as a backup flight control system in the design of a large, ultra-high capacity megatransport in such a way that flight path control using only the engines is not only possible, but meets MIL-Spec Level 1 or Level 2 handling quality requirements. An 800 passenger megatransport aircraft was designed and programmed into the NASA Dryden simulator. Many different analysis methods were used to evaluate the flying qualities of the megatransport while using engine thrust for flight path control, including: (1) Bode and root locus plot analysis to evaluate the frequency and damping ratio response of the megatransport; (2) analysis of actual simulator strip chart recordings to evaluate the time history response of the megatransport; and (3) analysis of Cooper-Harper pilot ratings by two NaSA test pilots.

  14. Manpower Requirements for Air Traffic Control and Flight Service Specialists in Indiana.

    Science.gov (United States)

    Purdue Univ., Lafayette, IN. Office of Manpower Studies.

    As of January 1, 1968 the Federal Aviation Administration (FAA) of the United States Department of Transportation employed 6,963 controllers in airport towers, 7,617 controllers in Air Route Traffic Control Centers, and 4,459 flight service specialists at airport locations. Projected needs are as follows: (1) Controllers in airport towers:…

  15. Design, analysis and control of hydraulic soft yaw system for 5MW wind turbine

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2012-01-01

    by active control of a hydraulic yaw system. The control is based on a non-linear and linear model derived based on a concept yaw system for the NREL 5MW wind turbine. The control strategies show a reduction in pressure pulsations under load and it is concluded that the strategie including high......As wind turbines increase in size and the demands for lifetime also increases, new methods of load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and wereby dampen the loads to the system. This paper presents work done on dampening of these loads...

  16. A Discrete-Time Chattering Free Sliding Mode Control with Multirate Sampling Method for Flight Simulator

    Directory of Open Access Journals (Sweden)

    Yunjie Wu

    2013-01-01

    Full Text Available In order to improve the tracking accuracy of flight simulator and expend its frequency response, a multirate-sampling-method-based discrete-time chattering free sliding mode control is developed and imported into the systems. By constructing the multirate sampling sliding mode controller, the flight simulator can perfectly track a given reference signal with an arbitrarily small dynamic tracking error, and the problems caused by a contradiction of reference signal period and control period in traditional design method can be eliminated. It is proved by theoretical analysis that the extremely high dynamic tracking precision can be obtained. Meanwhile, the robustness is guaranteed by sliding mode control even though there are modeling mismatch, external disturbances and measure noise. The validity of the proposed method is confirmed by experiments on flight simulator.

  17. Inherent Limitations of Hydraulic Tomography

    Science.gov (United States)

    Bohling, Geoffrey C.; Butler, J.J.

    2010-01-01

    We offer a cautionary note in response to an increasing level of enthusiasm regarding high-resolution aquifer characterization with hydraulic tomography. We use synthetic examples based on two recent field experiments to demonstrate that a high degree of nonuniqueness remains in estimates of hydraulic parameter fields even when those estimates are based on simultaneous analysis of a number of carefully controlled hydraulic tests. We must, therefore, be careful not to oversell the technique to the community of practicing hydrogeologists, promising a degree of accuracy and resolution that, in many settings, will remain unattainable, regardless of the amount of effort invested in the field investigation. No practically feasible amount of hydraulic tomography data will ever remove the need to regularize or bias the inverse problem in some fashion in order to obtain a unique solution. Thus, along with improving the resolution of hydraulic tomography techniques, we must also strive to couple those techniques with procedures for experimental design and uncertainty assessment and with other more cost-effective field methods, such as geophysical surveying and, in unconsolidated formations, direct-push profiling, in order to develop methods for subsurface characterization with the resolution and accuracy needed for practical field applications. Copyright ?? 2010 The Author(s). Journal compilation ?? 2010 National Ground Water Association.

  18. Design and performance characteristic analysis of servo valve-type water hydraulic poppet valve

    International Nuclear Information System (INIS)

    Park, Sung Hwan

    2009-01-01

    For water hydraulic system control, the flow or pressure control using high-speed solenoid valve controlled by PWM control method could be a good solution for prevention of internal leakage. However, since the PWM control of on-off valves cause extensive flow and pressure fluctuation, it is difficult to control the water hydraulic actuators precisely. In this study, the servo valve-type water hydraulic valve using proportional poppet as the main valve is designed and the performance characteristics of the servo valve-type water hydraulic valve are analyzed. Furthermore, it is demonstrated through experiments that a decline in control chamber pressure that follows the change of pilot flow is caused by the occurrence of cavitation around the proportional poppet, and that fundamental characteristics of the developed valve remain unaffected by the occurrence of cavitation

  19. Hydraulic Arm Modeling via Matlab SimHydraulics

    Czech Academy of Sciences Publication Activity Database

    Věchet, Stanislav; Krejsa, Jiří

    2009-01-01

    Roč. 16, č. 4 (2009), s. 287-296 ISSN 1802-1484 Institutional research plan: CEZ:AV0Z20760514 Keywords : simulatin modeling * hydraulics * SimHydraulics Subject RIV: JD - Computer Applications, Robotics

  20. Hydraulic fracture considerations in oil sand overburden dams

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R.; Madden, B.; Danku, M. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

    2008-07-01

    This paper discussed hydraulic fracture potential in the dry-filled temporary dams used in the oil sands industry. Hydraulic fractures can occur when reservoir fluid pressures are greater than the minimum stresses in a dam. Stress and strain conditions are influenced by pore pressures, levels of compaction in adjacent fills as well as by underlying pit floor and abutment conditions. Propagation pressure and crack initiation pressures must also be considered in order to provide improved hydraulic fracture protection to dams. Hydraulic fractures typically result in piping failures. Three cases of hydraulic fracture at oil sands operations in Alberta were presented. The study showed that hydraulic fracture failure modes must be considered in dam designs, particularly when thin compacted lift of dry fill are used to replace wetted clay cores. The risk of hydraulic fractures can be reduced by eliminating in situ bedrock irregularities and abutments. Overpressure heights, abutment sloping, and the sloping of fills above abutments, as well as the dam's width and base conditions must also be considered in relation to potential hydraulic fractures. It was concluded that upstream sand beaches and internal filters can help to prevent hydraulic fractures in dams in compacted control zones. 5 refs., 16 figs.