Design of a Simple and Modular 2-DOF Ankle Physiotherapy Device Relying on a Hybrid Serial-Parallel Robotic Architecture

Directory of Open Access Journals (Sweden)

Christos E. Syrseloudis

2011-01-01

Full Text Available The aim of this work is to propose a new 2-DOF robotic platform with hybrid parallel-serial structure and to undertake its parametric design so that it can follow the whole range of ankle related foot movements. This robot can serve as a human ankle rehabilitation device. The existing ankle rehabilitation devices present typically one or more of the following shortcomings: redundancy, large size, or high cost, hence the need for a device that could offer simplicity, modularity, and low cost of construction and maintenance. In addition, our targeted device must be safe during operation, disallow undesirable movements of the foot, while adaptable to any human foot. Our detailed study of foot kinematics has led us to a new hybrid architecture, which strikes a balance among all aforementioned goals. It consists of a passive serial kinematics chain with two adjustable screws so that the axes of the chain match the two main ankle-axes of typical feet. An active parallel chain, which consists of two prismatic actuators, provides the movement of the platform. Thus, the platform can follow the foot movements, thanks to the passive chain, and also possesses the advantages of parallel robots, including rigidity, high stiffness and force capabilities. The lack of redundancy yields a simpler device with lower size and cost. The paper describes the kinematics modelling of the platform and analyses the force and velocity transmission. The parametric design of the platform is carried out; our simulations confirm the platform's suitability for ankle rehabilitation.

Cognitive Coordination for Cooperative Multi-Robot Teamwork

NARCIS (Netherlands)

Wei, C.

2015-01-01

Multi-robot teams have potential advantages over a single robot. Robots in a team can serve different functionalities, so a team of robots can be more efficient, robust and reliable than a single robot. In this dissertation, we are in particular interested in human level intelligent multi-robot

Multi-Robot Assembly Strategies and Metrics

Science.gov (United States)

MARVEL, JEREMY A.; BOSTELMAN, ROGER; FALCO, JOE

2018-01-01

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles. In this survey, we identify the types of assemblies that are enabled by utilizing multiple robots, the algorithms that synchronize the motions of the robots to complete the assembly operations, and the metrics used to assess the quality and performance of the assemblies. PMID:29497234

Multi-Robot Assembly Strategies and Metrics.

Science.gov (United States)

Marvel, Jeremy A; Bostelman, Roger; Falco, Joe

2018-02-01

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles. In this survey, we identify the types of assemblies that are enabled by utilizing multiple robots, the algorithms that synchronize the motions of the robots to complete the assembly operations, and the metrics used to assess the quality and performance of the assemblies.

Multi-robot control interface

Science.gov (United States)

Bruemmer, David J [Idaho Falls, ID; Walton, Miles C [Idaho Falls, ID

2011-12-06

Methods and systems for controlling a plurality of robots through a single user interface include at least one robot display window for each of the plurality of robots with the at least one robot display window illustrating one or more conditions of a respective one of the plurality of robots. The user interface further includes at least one robot control window for each of the plurality of robots with the at least one robot control window configured to receive one or more commands for sending to the respective one of the plurality of robots. The user interface further includes a multi-robot common window comprised of information received from each of the plurality of robots.

Parametric Optimal Design of a Parallel Schönflies-Motion Robot under Pick-And-Place Trajectory Constraints

DEFF Research Database (Denmark)

Wu, Guanglei; Bai, Shaoping; Hjørnet, Preben

2015-01-01

This paper deals with the parametric optimum design of a parallel Schoenflies-motion robot, named "Ragnar", designed for fast and flexible pick-and-place applications. The robot architecture admits a rectangular workspace, which can utilize the shop-floor space efficiently. In this work......, the parametric models of the transmission quality, elasto-statics and dynamics are established. By taking into consideration of design requirements and pick-and-place trajectory, a comprehensive multi-objective optimization problem is formulated to optimize both kinematic and dynamic performances. The Pareto......-front is obtained, which provides optimal solutions to the robot design. Robot prototyping work based on the optimal results is described....

Optimal Design and Tuning of PID-Type Interval Type-2 Fuzzy Logic Controllers for Delta Parallel Robots

Directory of Open Access Journals (Sweden)

Xingguo Lu

2016-05-01

Full Text Available In this work, we propose a new method for the optimal design and tuning of a Proportional-Integral-Derivative type (PID-type interval type-2 fuzzy logic controller (IT2 FLC for Delta parallel robot trajectory tracking control. The presented methodology starts with an optimal design problem of IT2 FLC. A group of IT2 FLCs are obtained by blurring the membership functions using a variable called blurring degree. By comparing the performance of the controllers, the optimal structure of IT2 FLC is obtained. Then, a multi-objective optimization problem is formulated to tune the scaling factors of the PID-type IT2 FLC. The Non-dominated Sorting Genetic Algorithm (NSGA-II is adopted to solve the constrained nonlinear multi-objective optimization problem. Simulation results of the optimized controller are presented and discussed regarding application in the Delta parallel robot. The proposed method provides an effective way to design and tune the PID-type IT2 FLC with a desired control performance.

A mobile robot with parallel kinematics constructed under requirements for assembling and machining of the ITER vacuum vessel

International Nuclear Information System (INIS)

Pessi, P.; Huapeng Wu; Handroos, H.; Jones, L.

2006-01-01

ITER sectors require more stringent tolerances ± 5 mm than normally expected for the size of structure involved. The walls of ITER sectors are made of 60 mm thick stainless steel and are joined together by high efficiency structural and leak tight welds. In addition to the initial vacuum vessel assembly, sectors may have to be replaced for repair. Since commercially available machines are too heavy for the required machining operations and the lifting of a possible e-beam gun column system, and conventional robots lack the stiffness and accuracy in such machining condition, a new flexible, lightweight and mobile robotic machine is being considered. For the assembly of the ITER vacuum vessel sector, precise positioning of welding end-effectors, at some distance in a confined space from the available supports, will be required, which is not possible using conventional machines or robots. This paper presents a special robot, able to carry out welding and machining processes from inside the ITER vacuum vessel, consisting of a ten-degree-of-freedom parallel robot mounted on a carriage driven by electric motor/gearbox on a track. The robot consists of a Stewart platform based parallel mechanism. Water hydraulic cylinders are used as actuators to reach six degrees of freedom for parallel construction. Two linear and two rotational motions are used for enlargement the workspace of the manipulator. The robot carries both welding gun such as a TIG, hybrid laser or e-beam welding gun to weld the inner and outer walls of the ITER vacuum vessel sectors and machining tools to cut and milling the walls with necessary accuracy, it can also carry other tools and material to a required position inside the vacuum vessel . For assembling an on line six degrees of freedom seam finding algorithm has been developed, which enables the robot to find welding seam automatically in a very complex environment. In the machining multi flexible machining processes carried out automatically by

Kinematics and dynamics of a six-degree-of-freedom robot manipulator with closed kinematic chain mechanism

Science.gov (United States)

Nguyen, Charles C.; Pooran, Farhad J.

1989-01-01

This paper deals with a class of robot manipulators built based on the kinematic chain mechanism (CKCM). This class of CKCM manipulators consists of a fixed and a moving platform coupled together via a number of in-parallel actuators. A closed-form solution is derived for the inverse kinematic problem of a six-degre-of-freedom CKCM manipulator designed to study robotic applications in space. Iterative Newton-Raphson method is employed to solve the forward kinematic problem. Dynamics of the above manipulator is derived using the Lagrangian approach. Computer simulation of the dynamical equations shows that the actuating forces are strongly dependent on the mass and centroid of the robot links.

Analysis of jacobian and singularity of planar parallel robots using screw theory

Energy Technology Data Exchange (ETDEWEB)

Choi, Jung Hyun; Lee, Jeh Won; Lee, Hyuk Jin [Yeungnam Univ., Gyeongsan (Korea, Republic of)

2012-11-15

The Jacobian and singularity analysis of parallel robots is necessary to analyze robot motion. The derivations of the Jacobian matrix and singularity configuration are complicated and have no geometrical earning in the velocity form of the Jacobian matrix. In this study, the screw theory is used to derive the Jacobian of parallel robots. The statics form of the Jacobian has a geometrical meaning. In addition, singularity analysis can be performed by using the geometrical values. Furthermore, this study shows that the screw theory is applicable to redundantly actuated robots as well as non redundant robots.

Multi-Locomotion Robotic Systems New Concepts of Bio-inspired Robotics

CERN Document Server

Fukuda, Toshio; Sekiyama, Kosuke; Aoyama, Tadayoshi

2012-01-01

Nowadays, multiple attention have been paid on a robot working in the human living environment, such as in the field of medical, welfare, entertainment and so on. Various types of researches are being conducted actively in a variety of fields such as artificial intelligence, cognitive engineering, sensor- technology, interfaces and motion control. In the future, it is expected to realize super high functional human-like robot by integrating technologies in various fields including these types of researches. The book represents new developments and advances in the field of bio-inspired robotics research introducing the state of the art, the idea of multi-locomotion robotic system to implement the diversity of animal motion. It covers theoretical and computational aspects of Passive Dynamic Autonomous Control (PDAC), robot motion control, multi legged walking and climbing as well as brachiation focusing concrete robot systems, components and applications. In addition, gorilla type robot systems are described as...

Multi-robot caravanning

KAUST Repository

Denny, Jory

2013-11-01

We study multi-robot caravanning, which is loosely defined as the problem of a heterogeneous team of robots visiting specific areas of an environment (waypoints) as a group. After formally defining this problem, we propose a novel solution that requires minimal communication and scales with the number of waypoints and robots. Our approach restricts explicit communication and coordination to occur only when robots reach waypoints, and relies on implicit coordination when moving between a given pair of waypoints. At the heart of our algorithm is the use of leader election to efficiently exploit the unique environmental knowledge available to each robot in order to plan paths for the group, which makes it general enough to work with robots that have heterogeneous representations of the environment. We implement our approach both in simulation and on a physical platform, and characterize the performance of the approach under various scenarios. We demonstrate that our approach can successfully be used to combine the planning capabilities of different agents. © 2013 IEEE.

Design and Implementation of a New DELTA Parallel Robot in Robotics Competitions

Directory of Open Access Journals (Sweden)

Jonqlan Lin

2015-10-01

Full Text Available This investigation concerns the design and implementation of the DELTA parallel robot, covering the entire mechatronic process, involving kinematics, control design and optimizing methods. To accelerate the construction of the robot, 3D printing is used to fabricate end-effector parts. The parts are modular, low-cost, reconfigurable and can be assembled in less time than is required for conventionally fabricated parts. The controller, including the control algorithm and human-machine interface (HMI, is coded using the Borland C++ Builder 6 Personal software environment. The integration of the motion controller with image recognition into an opto-mechatronics system is presented. The robot system has been entered into robotic competitions in Taiwan. The experimental results reveal that the proposed DELTA robot completed the tasks in those competitions successfully.

Accuracy analysis of hybrid parallel robot for the assembling of ITER

Energy Technology Data Exchange (ETDEWEB)

Wang Yongbo [Institute of Mechatronics and Virtual Engineering, Lappeenranta University of Technology, Skinnarilankatu 34, 53850 Lappeenranta (Finland); The State Key Laboratory of Mechanical Transmission, Chongqing University (China); Pessi, Pekka [Institute of Mechatronics and Virtual Engineering, Lappeenranta University of Technology, Skinnarilankatu 34, 53850 Lappeenranta (Finland); Wu Huapeng [Institute of Mechatronics and Virtual Engineering, Lappeenranta University of Technology, Skinnarilankatu 34, 53850 Lappeenranta (Finland)], E-mail: huapeng@lut.fi; Handroos, Heikki [Institute of Mechatronics and Virtual Engineering, Lappeenranta University of Technology, Skinnarilankatu 34, 53850 Lappeenranta (Finland)

2009-06-15

This paper presents a novel mobile parallel robot, which is able to carry welding and machining processes from inside the international thermonuclear experimental reactor (ITER) vacuum vessel (VV). The kinematics design of the robot has been optimized for ITER access. To improve the accuracy of the parallel robot, the errors caused by the stiffness and manufacture process have to be compensated or limited to a minimum value. In this paper kinematics errors and stiffness modeling are given. The simulation results are presented.

Accuracy analysis of hybrid parallel robot for the assembling of ITER

International Nuclear Information System (INIS)

Wang Yongbo; Pessi, Pekka; Wu Huapeng; Handroos, Heikki

2009-01-01

This paper presents a novel mobile parallel robot, which is able to carry welding and machining processes from inside the international thermonuclear experimental reactor (ITER) vacuum vessel (VV). The kinematics design of the robot has been optimized for ITER access. To improve the accuracy of the parallel robot, the errors caused by the stiffness and manufacture process have to be compensated or limited to a minimum value. In this paper kinematics errors and stiffness modeling are given. The simulation results are presented.

Multi-Robot Remote Interaction with FS-MAS

Directory of Open Access Journals (Sweden)

Yunliang Jiang

2013-02-01

Full Text Available The need to reduce bandwidth, improve productivity, autonomy and the scalability in multi-robot teleoperation has been recognized for a long time. In this article we propose a novel finite state machine mobile agent based on the network interaction service model, namely FS-MAS. This model consists of three finite state machines, namely the Finite State Mobile Agent (FS-Agent, which is the basic service module. The Service Content Finite State Machine (Content-FS, using the XML language to define workflow, to describe service content and service computation process. The Mobile Agent computation model Finite State Machine (MACM-FS, used to describe the service implementation. Finally, we apply this service model to the multi-robot system, the initial realization completing complex tasks in the form of multi-robot scheduling. This demonstrates that the robot has greatly improved intelligence, and provides a wide solution space for critical issues such as task division, rational and efficient use of resource and multi-robot collaboration.

A parallel robot to assist vitreoretinal surgery

Energy Technology Data Exchange (ETDEWEB)

Nakano, Taiga; Sugita, Naohiko; Mitsuishi, Mamoru [University of Tokyo, School of Engineering, Tokyo (Japan); Ueta, Takashi; Tamaki, Yasuhiro [University of Tokyo, Graduate School of Medicine, Tokyo (Japan)

2009-11-15

This paper describes the development and evaluation of a parallel prototype robot for vitreoretinal surgery where physiological hand tremor limits performance. The manipulator was specifically designed to meet requirements such as size, precision, and sterilization; this has six-degree-of-freedom parallel architecture and provides positioning accuracy with micrometer resolution within the eye. The manipulator is controlled by an operator with a ''master manipulator'' consisting of multiple joints. Results of the in vitro experiments revealed that when compared to the manual procedure, a higher stability and accuracy of tool positioning could be achieved using the prototype robot. This microsurgical system that we have developed has superior operability as compared to traditional manual procedure and has sufficient potential to be used clinically for vitreoretinal surgery. (orig.)

Kinematics and dynamics analysis of a quadruped walking robot with parallel leg mechanism

Science.gov (United States)

Wang, Hongbo; Sang, Lingfeng; Hu, Xing; Zhang, Dianfan; Yu, Hongnian

2013-09-01

It is desired to require a walking robot for the elderly and the disabled to have large capacity, high stiffness, stability, etc. However, the existing walking robots cannot achieve these requirements because of the weight-payload ratio and simple function. Therefore, Improvement of enhancing capacity and functions of the walking robot is an important research issue. According to walking requirements and combining modularization and reconfigurable ideas, a quadruped/biped reconfigurable walking robot with parallel leg mechanism is proposed. The proposed robot can be used for both a biped and a quadruped walking robot. The kinematics and performance analysis of a 3-UPU parallel mechanism which is the basic leg mechanism of a quadruped walking robot are conducted and the structural parameters are optimized. The results show that performance of the walking robot is optimal when the circumradius R, r of the upper and lower platform of leg mechanism are 161.7 mm, 57.7 mm, respectively. Based on the optimal results, the kinematics and dynamics of the quadruped walking robot in the static walking mode are derived with the application of parallel mechanism and influence coefficient theory, and the optimal coordination distribution of the dynamic load for the quadruped walking robot with over-determinate inputs is analyzed, which solves dynamic load coupling caused by the branches’ constraint of the robot in the walk process. Besides laying a theoretical foundation for development of the prototype, the kinematics and dynamics studies on the quadruped walking robot also boost the theoretical research of the quadruped walking and the practical applications of parallel mechanism.

Robotic tool positioning process using a multi-line off-axis laser triangulation sensor

Science.gov (United States)

Pinto, T. C.; Matos, G.

2018-03-01

Proper positioning of a friction stir welding head for pin insertion, driven by a closed chain robot, is important to ensure quality repair of cracks. A multi-line off-axis laser triangulation sensor was designed to be integrated to the robot, allowing relative measurements of the surface to be repaired. This work describes the sensor characteristics, its evaluation and the measurement process for tool positioning to a surface point of interest. The developed process uses a point of interest image and a measured point cloud to define the translation and rotation for tool positioning. Sensor evaluation and tests are described. Keywords: laser triangulation, 3D measurement, tool positioning, robotics.

Continuous path control of a 5-DOF parallel-serial hybrid robot

International Nuclear Information System (INIS)

Uchiyama, Takuma; Terada, Hidetsugu; Mitsuya, Hironori

2010-01-01

Using the 5-degree of freedom parallel-serial hybrid robot, to realize the de-burring, new forward and inverse kinematic calculation methods based on the 'off-line teaching' method are proposed. This hybrid robot consists of a parallel stage section and a serial stage section. Considering this point, each section is calculated individually. And the continuous path control algorithm of this hybrid robot is proposed. To verify the usefulness, a prototype robot is tested which is controlled based on the proposed methods. This verification includes a positioning test and a pose test. The positioning test evaluates the continuous path of the tool center point. The pose test evaluates the pose on the tool center point. As the result, it is confirmed that this hybrid robot moves correctly using the proposed methods

Evaluation of the power consumption of a high-speed parallel robot

Science.gov (United States)

Han, Gang; Xie, Fugui; Liu, Xin-Jun

2018-06-01

An inverse dynamic model of a high-speed parallel robot is established based on the virtual work principle. With this dynamic model, a new evaluation method is proposed to measure the power consumption of the robot during pick-and-place tasks. The power vector is extended in this method and used to represent the collinear velocity and acceleration of the moving platform. Afterward, several dynamic performance indices, which are homogenous and possess obvious physical meanings, are proposed. These indices can evaluate the power input and output transmissibility of the robot in a workspace. The distributions of the power input and output transmissibility of the high-speed parallel robot are derived with these indices and clearly illustrated in atlases. Furtherly, a low-power-consumption workspace is selected for the robot.

2nd International Conference on Cable-Driven Parallel Robots

CERN Document Server

Bruckmann, Tobias

2015-01-01

This volume presents the outcome of the second forum to cable-driven parallel robots, bringing the cable robot community together. It shows the new ideas of the active researchers developing cable-driven robots. The book presents the state of the art, including both summarizing contributions as well as latest research and future options. The book cover all topics which are essential for cable-driven robots: Classification Kinematics, Workspace and Singularity Analysis Statics and Dynamics Cable Modeling Control and Calibration Design Methodology Hardware Development Experimental Evaluation Prototypes, Application Reports and new Application concepts

On the Minimum Cable Tensions for the Cable-Based Parallel Robots

Directory of Open Access Journals (Sweden)

Peng Liu

2014-01-01

Full Text Available This paper investigates the minimum cable tension distributions in the workspace for cable-based parallel robots to find out more information on the stability. First, the kinematic model of a cable-based parallel robot is derived based on the wrench matrix. Then, a noniterative polynomial-based optimization algorithm with the proper optimal objective function is presented based on the convex optimization theory, in which the minimum cable tension at any pose is determined. Additionally, three performance indices are proposed to show the distributions of the minimum cable tensions in a specified region of the workspace. An important thing is that the three performance indices can be used to evaluate the stability of the cable-based parallel robots. Furthermore, a new workspace, the Specified Minimum Cable Tension Workspace (SMCTW, is introduced, within which all the minimum tensions exceed a specified value, therefore meeting the specified stability requirement. Finally, a camera robot parallel driven by four cables for aerial panoramic photographing is selected to illustrate the distributions of the minimum cable tensions in the workspace and the relationship between the three performance indices and the stability.

Development of a 3D parallel mechanism robot arm with three vertical-axial pneumatic actuators combined with a stereo vision system.

Science.gov (United States)

Chiang, Mao-Hsiung; Lin, Hao-Ting

2011-01-01

This study aimed to develop a novel 3D parallel mechanism robot driven by three vertical-axial pneumatic actuators with a stereo vision system for path tracking control. The mechanical system and the control system are the primary novel parts for developing a 3D parallel mechanism robot. In the mechanical system, a 3D parallel mechanism robot contains three serial chains, a fixed base, a movable platform and a pneumatic servo system. The parallel mechanism are designed and analyzed first for realizing a 3D motion in the X-Y-Z coordinate system of the robot's end-effector. The inverse kinematics and the forward kinematics of the parallel mechanism robot are investigated by using the Denavit-Hartenberg notation (D-H notation) coordinate system. The pneumatic actuators in the three vertical motion axes are modeled. In the control system, the Fourier series-based adaptive sliding-mode controller with H(∞) tracking performance is used to design the path tracking controllers of the three vertical servo pneumatic actuators for realizing 3D path tracking control of the end-effector. Three optical linear scales are used to measure the position of the three pneumatic actuators. The 3D position of the end-effector is then calculated from the measuring position of the three pneumatic actuators by means of the kinematics. However, the calculated 3D position of the end-effector cannot consider the manufacturing and assembly tolerance of the joints and the parallel mechanism so that errors between the actual position and the calculated 3D position of the end-effector exist. In order to improve this situation, sensor collaboration is developed in this paper. A stereo vision system is used to collaborate with the three position sensors of the pneumatic actuators. The stereo vision system combining two CCD serves to measure the actual 3D position of the end-effector and calibrate the error between the actual and the calculated 3D position of the end-effector. Furthermore, to

A Multi-Sensorial Hybrid Control for Robotic Manipulation in Human-Robot Workspaces

Directory of Open Access Journals (Sweden)

Juan A. Corrales

2011-10-01

Full Text Available Autonomous manipulation in semi-structured environments where human operators can interact is an increasingly common task in robotic applications. This paper describes an intelligent multi-sensorial approach that solves this issue by providing a multi-robotic platform with a high degree of autonomy and the capability to perform complex tasks. The proposed sensorial system is composed of a hybrid visual servo control to efficiently guide the robot towards the object to be manipulated, an inertial motion capture system and an indoor localization system to avoid possible collisions between human operators and robots working in the same workspace, and a tactile sensor algorithm to correctly manipulate the object. The proposed controller employs the whole multi-sensorial system and combines the measurements of each one of the used sensors during two different phases considered in the robot task: a first phase where the robot approaches the object to be grasped, and a second phase of manipulation of the object. In both phases, the unexpected presence of humans is taken into account. This paper also presents the successful results obtained in several experimental setups which verify the validity of the proposed approach.

Multi-Robot, Multi-Target Particle Swarm Optimization Search in Noisy Wireless Environments

Energy Technology Data Exchange (ETDEWEB)

Kurt Derr; Milos Manic

2009-05-01

Multiple small robots (swarms) can work together using Particle Swarm Optimization (PSO) to perform tasks that are difficult or impossible for a single robot to accomplish. The problem considered in this paper is exploration of an unknown environment with the goal of finding a target(s) at an unknown location(s) using multiple small mobile robots. This work demonstrates the use of a distributed PSO algorithm with a novel adaptive RSS weighting factor to guide robots for locating target(s) in high risk environments. The approach was developed and analyzed on multiple robot single and multiple target search. The approach was further enhanced by the multi-robot-multi-target search in noisy environments. The experimental results demonstrated how the availability of radio frequency signal can significantly affect robot search time to reach a target.

Neural Behavior Chain Learning of Mobile Robot Actions

Directory of Open Access Journals (Sweden)

Lejla Banjanovic-Mehmedovic

2012-01-01

Full Text Available This paper presents a visual/motor behavior learning approach, based on neural networks. We propose Behavior Chain Model (BCM in order to create a way of behavior learning. Our behavior-based system evolution task is a mobile robot detecting a target and driving/acting towards it. First, the mapping relations between the image feature domain of the object and the robot action domain are derived. Second, a multilayer neural network for offline learning of the mapping relations is used. This learning structure through neural network training process represents a connection between the visual perceptions and motor sequence of actions in order to grip a target. Last, using behavior learning through a noticed action chain, we can predict mobile robot behavior for a variety of similar tasks in similar environment. Prediction results suggest that the methodology is adequate and could be recognized as an idea for designing different mobile robot behaviour assistance.

On Open- source Multi-robot simulators

CSIR Research Space (South Africa)

Namoshe, M

2008-07-01

Full Text Available Open source software simulators play a major role in robotics design and research as platforms for developing, testing and improving architectures, concepts and algorithms for cooperative/multi-robot systems. Simulation environment enables control...

Multi-Robot Item Delivery and Foraging: Two Sides of a Coin

Directory of Open Access Journals (Sweden)

Somchaya Liemhetcharat

2015-09-01

Full Text Available Multi-robot foraging has been widely studied in the literature, and the general assumption is that the robots are simple, i.e., with limited processing and carrying capacity. We previously studied continuous foraging with slightly more capable robots, and in this article, we are interested in using similar robots for item delivery. Interestingly, item delivery and foraging are two sides of the same coin: foraging an item from a location is similar to satisfying a demand. We formally define the multi-robot item delivery problem and show that the continuous foraging problem is a special case of it. We contribute distributed multi-robot algorithms that solve the item delivery and foraging problems and describe how our shared world model is synchronized across the multi-robot team. We performed extensive experiments on simulated robots using a Java simulator, and we present our results to demonstrate that we outperform benchmark algorithms from multi-robot foraging.

Multi-robot Cooperation Behavior Decision Based on Psychological Values

Directory of Open Access Journals (Sweden)

Jian JIANG

2014-01-01

Full Text Available The method based on psychology concept has been proved to be a successful tool used for human-robot interaction. But its related research in multi-robot cooperation has remained scarce until recent studies. To solve the problem, a decision-making mechanism based on psychological values is presented to be regarded as the basis of the multi-robot cooperation. Robots give birth to psychological values based on the estimations of environment, teammates and themselves. The mapping relationship between psychological values and cooperation tendency threshold values is set up with artificial neural network. Robots can make decision on the bases of these threshold values in cooperation scenes. Experiments show that the multi-robot cooperation method presented in the paper not only can ensure the rationality of robots’ decision-making, but also can ensure the speediness of robots’ decision-making.

Towards Coordination and Control of Multi-robot Systems

DEFF Research Database (Denmark)

Quottrup, Michael Melholt

This thesis focuses on control and coordination of mobile multi-robot systems (MRS). MRS can often deal with tasks that are difficult to be accomplished by a single robot. One of the challenges is the need to control, coordinate and synchronize the operation of several robots to perform some...... specified task. This calls for new strategies and methods which allow the desired system behavior to be specified in a formal and succinct way. Two different frameworks for the coordination and control of MRS have been investigated. Framework I - A network of robots is modeled as a network of multi...... a requirement specification in Computational Tree Logic (CTL) for a network of robots. The result is a set of motion plans for the robots which satisfy the specification. Framework II - A framework for controller synthesis for a single robot with respect to requirement specification in Linear-time Temporal...

Parallelized event chain algorithm for dense hard sphere and polymer systems

International Nuclear Information System (INIS)

Kampmann, Tobias A.; Boltz, Horst-Holger; Kierfeld, Jan

2015-01-01

We combine parallelization and cluster Monte Carlo for hard sphere systems and present a parallelized event chain algorithm for the hard disk system in two dimensions. For parallelization we use a spatial partitioning approach into simulation cells. We find that it is crucial for correctness to ensure detailed balance on the level of Monte Carlo sweeps by drawing the starting sphere of event chains within each simulation cell with replacement. We analyze the performance gains for the parallelized event chain and find a criterion for an optimal degree of parallelization. Because of the cluster nature of event chain moves massive parallelization will not be optimal. Finally, we discuss first applications of the event chain algorithm to dense polymer systems, i.e., bundle-forming solutions of attractive semiflexible polymers

Research status of multi - robot systems task allocation and uncertainty treatment

Science.gov (United States)

Li, Dahui; Fan, Qi; Dai, Xuefeng

2017-08-01

The multi-robot coordination algorithm has become a hot research topic in the field of robotics in recent years. It has a wide range of applications and good application prospects. This paper analyzes and summarizes the current research status of multi-robot coordination algorithms at home and abroad. From task allocation and dealing with uncertainty, this paper discusses the multi-robot coordination algorithm and presents the advantages and disadvantages of each method commonly used.

Screw Theory Based Singularity Analysis of Lower-Mobility Parallel Robots considering the Motion/Force Transmissibility and Constrainability

Directory of Open Access Journals (Sweden)

Xiang Chen

2015-01-01

Full Text Available Singularity is an inherent characteristic of parallel robots and is also a typical mathematical problem in engineering application. In general, to identify singularity configuration, the singular solution in mathematics should be derived. This work introduces an alternative approach to the singularity identification of lower-mobility parallel robots considering the motion/force transmissibility and constrainability. The theory of screws is used as the mathematic tool to define the transmission and constraint indices of parallel robots. The singularity is hereby classified into four types concerning both input and output members of a parallel robot, that is, input transmission singularity, output transmission singularity, input constraint singularity, and output constraint singularity. Furthermore, we take several typical parallel robots as examples to illustrate the process of singularity analysis. Particularly, the input and output constraint singularities which are firstly proposed in this work are depicted in detail. The results demonstrate that the method can not only identify all possible singular configurations, but also explain their physical meanings. Therefore, the proposed approach is proved to be comprehensible and effective in solving singularity problems in parallel mechanisms.

Distributed consensus with visual perception in multi-robot systems

CERN Document Server

Montijano, Eduardo

2015-01-01

This monograph introduces novel responses to the different problems that arise when multiple robots need to execute a task in cooperation, each robot in the team having a monocular camera as its primary input sensor. Its central proposition is that a consistent perception of the world is crucial for the good development of any multi-robot application. The text focuses on the high-level problem of cooperative perception by a multi-robot system: the idea that, depending on what each robot sees and its current situation, it will need to communicate these things to its fellows whenever possible to share what it has found and keep updated by them in its turn. However, in any realistic scenario, distributed solutions to this problem are not trivial and need to be addressed from as many angles as possible. Distributed Consensus with Visual Perception in Multi-Robot Systems covers a variety of related topics such as: ·         distributed consensus algorithms; ·         data association and robustne...

Kinematics and Dynamics of an Asymmetrical Parallel Robotic Wrist

DEFF Research Database (Denmark)

Wu, Guanglei

2014-01-01

This paper introduces an asymmetrical parallel robotic wrist, which can generate a decoupled unlimited-torsion motion and achieve high positioning accuracy. The kinematics, dexterity, and singularities of the manipulator are investigated to visualize the performance contours of the manipulator...

Multi-sensor measurement system for robotic drilling

OpenAIRE

Frommknecht, Andreas; Kühnle, Jens; Pidan, Sergej; Effenberger, Ira

2015-01-01

A multi-sensor measurement system for robotic drilling is presented. The system enables a robot to measure its 6D pose with respect to the work piece and to establish a reference coordinate system for drilling. The robot approaches the drill point and performs an orthogonal alignment with the work piece. Although the measurement systems are readily capable of achieving high position accuracy and low deviation to perpendicularity, experiments show that inaccuracies in the robot's 6D-pose and e...

Fast robot kinematics modeling by using a parallel simulator (PSIM)

International Nuclear Information System (INIS)

El-Gazzar, H.M.; Ayad, N.M.A.

2002-01-01

High-speed computers are strongly needed not only for solving scientific and engineering problems, but also for numerous industrial applications. Such applications include computer-aided design, oil exploration, weather predication, space applications and safety of nuclear reactors. The rapid development in VLSI technology makes it possible to implement time consuming algorithms in real-time situations. Parallel processing approaches can now be used to reduce the processing-time for models of very high mathematical structure such as the kinematics molding of robot manipulator. This system is used to construct and evaluate the performance and cost effectiveness of several proposed methods to solve the Jacobian algorithm. Parallelism is introduced to the algorithms by using different task-allocations and dividing the whole job into sub tasks. Detailed analysis is performed and results are obtained for the case of six DOF (degree of freedom) robot arms (Stanford Arm). Execution times comparisons between Von Neumann (uni processor) and parallel processor architectures by using parallel simulator package (PSIM) are presented. The gained results are much in favour for the parallel techniques by at least fifty-percent improvements. Of course, further studies are needed to achieve the convenient and optimum number of processors has to be done

Fast robot kinematics modeling by using a parallel simulator (PSIM)

Energy Technology Data Exchange (ETDEWEB)

El-Gazzar, H M; Ayad, N M.A. [Atomic Energy Authority, Reactor Dept., Computer and Control Lab., P.O. Box no 13759 (Egypt)

2002-09-15

High-speed computers are strongly needed not only for solving scientific and engineering problems, but also for numerous industrial applications. Such applications include computer-aided design, oil exploration, weather predication, space applications and safety of nuclear reactors. The rapid development in VLSI technology makes it possible to implement time consuming algorithms in real-time situations. Parallel processing approaches can now be used to reduce the processing-time for models of very high mathematical structure such as the kinematics molding of robot manipulator. This system is used to construct and evaluate the performance and cost effectiveness of several proposed methods to solve the Jacobian algorithm. Parallelism is introduced to the algorithms by using different task-allocations and dividing the whole job into sub tasks. Detailed analysis is performed and results are obtained for the case of six DOF (degree of freedom) robot arms (Stanford Arm). Execution times comparisons between Von Neumann (uni processor) and parallel processor architectures by using parallel simulator package (PSIM) are presented. The gained results are much in favour for the parallel techniques by at least fifty-percent improvements. Of course, further studies are needed to achieve the convenient and optimum number of processors has to be done.

Robot-assisted ultrasound imaging: overview and development of a parallel telerobotic system.

Science.gov (United States)

Monfaredi, Reza; Wilson, Emmanuel; Azizi Koutenaei, Bamshad; Labrecque, Brendan; Leroy, Kristen; Goldie, James; Louis, Eric; Swerdlow, Daniel; Cleary, Kevin

2015-02-01

Ultrasound imaging is frequently used in medicine. The quality of ultrasound images is often dependent on the skill of the sonographer. Several researchers have proposed robotic systems to aid in ultrasound image acquisition. In this paper we first provide a short overview of robot-assisted ultrasound imaging (US). We categorize robot-assisted US imaging systems into three approaches: autonomous US imaging, teleoperated US imaging, and human-robot cooperation. For each approach several systems are introduced and briefly discussed. We then describe a compact six degree of freedom parallel mechanism telerobotic system for ultrasound imaging developed by our research team. The long-term goal of this work is to enable remote ultrasound scanning through teleoperation. This parallel mechanism allows for both translation and rotation of an ultrasound probe mounted on the top plate along with force control. Our experimental results confirmed good mechanical system performance with a positioning error of < 1 mm. Phantom experiments by a radiologist showed promising results with good image quality.

Adaptive Controller for 6-DOF Parallel Robot Using T-S Fuzzy Inference

Directory of Open Access Journals (Sweden)

Xue Jian

2013-02-01

Full Text Available 6-DOF parallel robot always appears in the form of Stewart platform. It has been widely used in industry for the benefits such as strong structural stiffness, high movement accuracy and so on. Space docking technology makes higher requirements of motion accuracy and dynamic performance to the control method on 6-DOF parallel robot. In this paper, a hydraulic 6-DOF parallel robot was used to simulate the docking process. Based on this point, this paper gave a thorough study on the design of an adaptive controller to eliminate the asymmetric of controlled plant and uncertain load force interference. Takagi-Sugeno (T-S fuzzy inference model was used to build the fuzzy adaptive controller. With T-S model, the controller directly imposes adaptive control signal on the plant to make sure that the output of plant could track the reference model output. The controller has simple structure and is easy to implement. Experiment results show that the controller can eliminate asymmetric and achieve good dynamic performance, and has good robustness to load interference.

Kinematics and Application of a Hybrid Industrial Robot – Delta-RST

Directory of Open Access Journals (Sweden)

Ning Liu

2014-04-01

Full Text Available Serial robots and parallel robots have their own pros and cons. While hybrid robots consisting of both of them are possible and expected to retain their merits and minimize the disadvantages. The Delta-RST presented here is such a hybrid robot built up by integrating a 3-DoFs traditional Delta parallel structure and a 3-DoFs RST robotic wrist. In this paper, we focus on its kinematics analysis and its applications in industry. Firstly, the robotic system of the Delta-RST will be described briefly. Then the complete and systemic kinematics of this kind of robot will be presented in detail, followed by simulations and applications to demonstrate the correctness of the analysis, as well as the effectiveness of the developed robotic system. The closed-form kinematic analysis results are universal for similar hybrid robots constructing with the Delta parallel mechanism and serial chains.

Advantages of Task-Specific Multi-Objective Optimisation in Evolutionary Robotics.

Science.gov (United States)

Trianni, Vito; López-Ibáñez, Manuel

2015-01-01

The application of multi-objective optimisation to evolutionary robotics is receiving increasing attention. A survey of the literature reveals the different possibilities it offers to improve the automatic design of efficient and adaptive robotic systems, and points to the successful demonstrations available for both task-specific and task-agnostic approaches (i.e., with or without reference to the specific design problem to be tackled). However, the advantages of multi-objective approaches over single-objective ones have not been clearly spelled out and experimentally demonstrated. This paper fills this gap for task-specific approaches: starting from well-known results in multi-objective optimisation, we discuss how to tackle commonly recognised problems in evolutionary robotics. In particular, we show that multi-objective optimisation (i) allows evolving a more varied set of behaviours by exploring multiple trade-offs of the objectives to optimise, (ii) supports the evolution of the desired behaviour through the introduction of objectives as proxies, (iii) avoids the premature convergence to local optima possibly introduced by multi-component fitness functions, and (iv) solves the bootstrap problem exploiting ancillary objectives to guide evolution in the early phases. We present an experimental demonstration of these benefits in three different case studies: maze navigation in a single robot domain, flocking in a swarm robotics context, and a strictly collaborative task in collective robotics.

Advantages of Task-Specific Multi-Objective Optimisation in Evolutionary Robotics.

Directory of Open Access Journals (Sweden)

Vito Trianni

Full Text Available The application of multi-objective optimisation to evolutionary robotics is receiving increasing attention. A survey of the literature reveals the different possibilities it offers to improve the automatic design of efficient and adaptive robotic systems, and points to the successful demonstrations available for both task-specific and task-agnostic approaches (i.e., with or without reference to the specific design problem to be tackled. However, the advantages of multi-objective approaches over single-objective ones have not been clearly spelled out and experimentally demonstrated. This paper fills this gap for task-specific approaches: starting from well-known results in multi-objective optimisation, we discuss how to tackle commonly recognised problems in evolutionary robotics. In particular, we show that multi-objective optimisation (i allows evolving a more varied set of behaviours by exploring multiple trade-offs of the objectives to optimise, (ii supports the evolution of the desired behaviour through the introduction of objectives as proxies, (iii avoids the premature convergence to local optima possibly introduced by multi-component fitness functions, and (iv solves the bootstrap problem exploiting ancillary objectives to guide evolution in the early phases. We present an experimental demonstration of these benefits in three different case studies: maze navigation in a single robot domain, flocking in a swarm robotics context, and a strictly collaborative task in collective robotics.

Multi-robot team design for real-world applications

Energy Technology Data Exchange (ETDEWEB)

Parker, L.E.

1996-10-01

Many of these applications are in dynamic environments requiring capabilities distributed in functionality, space, or time, and therefore often require teams of robots to work together. While much research has been done in recent years, current robotics technology is still far from achieving many of the real world applications. Two primary reasons for this technology gap are that (1) previous work has not adequately addressed the issues of fault tolerance and adaptivity in multi-robot teams, and (2) existing robotics research is often geared at specific applications and is not easily generalized to different, but related, applications. This paper addresses these issues by first describing the design issues of key importance in these real-world cooperative robotics applications: fault tolerance, reliability, adaptivity, and coherence. We then present a general architecture addressing these design issues (called ALLIANCE) that facilities multi-robot cooperation of small- to medium-sized teams in dynamic environments, performing missions composed of loosely coupled subtasks. We illustrate an implementation of ALLIANCE in a real-world application, called Bounding Overwatch, and then discuss how this architecture addresses our key design issues.

IMPERA: Integrated Mission Planning for Multi-Robot Systems

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Daniel Saur

2015-10-01

Full Text Available This paper presents the results of the project IMPERA (Integrated Mission Planning for Distributed Robot Systems. The goal of IMPERA was to realize an extraterrestrial exploration scenario using a heterogeneous multi-robot system. The main challenge was the development of a multi-robot planning and plan execution architecture. The robot team consists of three heterogeneous robots, which have to explore an unknown environment and collect lunar drill samples. The team activities are described using the language ALICA (A Language for Interactive Agents. Furthermore, we use the mission planning system pRoPhEt MAS (Reactive Planning Engine for Multi-Agent Systems to provide an intuitive interface to generate team activities. Therefore, we define the basic skills of our team with ALICA and define the desired goal states by using a logic description. Based on the skills, pRoPhEt MAS creates a valid ALICA plan, which will be executed by the team. The paper describes the basic components for communication, coordinated exploration, perception and object transportation. Finally, we evaluate the planning engine pRoPhEt MAS in the IMPERA scenario. In addition, we present further evaluation of pRoPhEt MAS in more dynamic environments.

Design and Nonlinear Control of a 2-DOF Flexible Parallel Humanoid Arm Joint Robot

Directory of Open Access Journals (Sweden)

Leijie Jiang

2017-01-01

Full Text Available The paper focuses on the design and nonlinear control of the humanoid wrist/shoulder joint based on the cable-driven parallel mechanism which can realize roll and pitch movement. In view of the existence of the flexible parts in the mechanism, it is necessary to solve the vibration control of the flexible wrist/shoulder joint. In this paper, a cable-driven parallel robot platform is developed for the experiment study of the humanoid wrist/shoulder joint. And the dynamic model of the mechanism is formulated by using the coupling theory of the flexible body’s large global motion and small flexible deformation. Based on derived dynamics, antivibration control of the joint robot is studied with a nonlinear control method. Finally, simulations and experiments were performed to validate the feasibility of the developed parallel robot prototype and the proposed control scheme.

Development of a novel soft parallel robot equipped with polymeric artificial muscles

International Nuclear Information System (INIS)

Moghadam, Amir Ali Amiri; Kouzani, Abbas; Kaynak, Akif; Torabi, Keivan; Shahinpoor, Mohsen

2015-01-01

This paper presents the design, analysis and fabrication of a novel low-cost soft parallel robot for biomedical applications, including bio-micromanipulation devices. The robot consists of two active flexible polymer actuator-based links, which are connected to two rigid links by means of flexible joints. A mathematical model is established between the input voltage to the polymer actuators and the robot’s end effector position. The robot has two degrees-of-freedom, making it suitable for handling planar micromanipulation tasks. Moreover, a number of robots can be configured to operate in a cooperative manner for increasing micromanipulation dexterity. Finally, the experimental results demonstrate two main motion modes of the robot. (paper)

A Review of Parallel Processing Approaches to Robot Kinematics and Jacobian

OpenAIRE

Henrich, Dominik; Karl, Joachim; Wörn, Heinz

1997-01-01

Due to continuously increasing demands in the area of advanced robot control, it became necessary to speed up the computation. One way to reduce the computation time is to distribute the computation onto several processing units. In this survey we present different approaches to parallel computation of robot kinematics and Jacobian. Thereby, we discuss both the forward and the reverse problem. We introduce a classification scheme and class...

A Spatial Queuing-Based Algorithm for Multi-Robot Task Allocation

Directory of Open Access Journals (Sweden)

William Lenagh

2015-08-01

Full Text Available Multi-robot task allocation (MRTA is an important area of research in autonomous multi-robot systems. The main problem in MRTA is to allocate a set of tasks to a set of robots so that the tasks can be completed by the robots while ensuring that a certain metric, such as the time required to complete all tasks, or the distance traveled, or the energy expended by the robots is reduced. We consider a scenario where tasks can appear dynamically and a task needs to be performed by multiple robots to be completed. We propose a new algorithm called SQ-MRTA (Spatial Queueing-MRTA that uses a spatial queue-based model to allocate tasks between robots in a distributed manner. We have implemented the SQ-MRTA algorithm on accurately simulated models of Corobot robots within the Webots simulator for different numbers of robots and tasks and compared its performance with other state-of-the-art MRTA algorithms. Our results show that the SQ-MRTA algorithm is able to scale up with the number of tasks and robots in the environment, and it either outperforms or performs comparably with respect to other distributed MRTA algorithms.

Heterogeneous Multi-Robot System for Mapping Environmental Variables of Greenhouses.

Science.gov (United States)

Roldán, Juan Jesús; Garcia-Aunon, Pablo; Garzón, Mario; de León, Jorge; Del Cerro, Jaime; Barrientos, Antonio

2016-07-01

The productivity of greenhouses highly depends on the environmental conditions of crops, such as temperature and humidity. The control and monitoring might need large sensor networks, and as a consequence, mobile sensory systems might be a more suitable solution. This paper describes the application of a heterogeneous robot team to monitor environmental variables of greenhouses. The multi-robot system includes both ground and aerial vehicles, looking to provide flexibility and improve performance. The multi-robot sensory system measures the temperature, humidity, luminosity and carbon dioxide concentration in the ground and at different heights. Nevertheless, these measurements can be complemented with other ones (e.g., the concentration of various gases or images of crops) without a considerable effort. Additionally, this work addresses some relevant challenges of multi-robot sensory systems, such as the mission planning and task allocation, the guidance, navigation and control of robots in greenhouses and the coordination among ground and aerial vehicles. This work has an eminently practical approach, and therefore, the system has been extensively tested both in simulations and field experiments.

Heterogeneous Multi-Robot System for Mapping Environmental Variables of Greenhouses

Directory of Open Access Journals (Sweden)

Juan Jesús Roldán

2016-07-01

Full Text Available The productivity of greenhouses highly depends on the environmental conditions of crops, such as temperature and humidity. The control and monitoring might need large sensor networks, and as a consequence, mobile sensory systems might be a more suitable solution. This paper describes the application of a heterogeneous robot team to monitor environmental variables of greenhouses. The multi-robot system includes both ground and aerial vehicles, looking to provide flexibility and improve performance. The multi-robot sensory system measures the temperature, humidity, luminosity and carbon dioxide concentration in the ground and at different heights. Nevertheless, these measurements can be complemented with other ones (e.g., the concentration of various gases or images of crops without a considerable effort. Additionally, this work addresses some relevant challenges of multi-robot sensory systems, such as the mission planning and task allocation, the guidance, navigation and control of robots in greenhouses and the coordination among ground and aerial vehicles. This work has an eminently practical approach, and therefore, the system has been extensively tested both in simulations and field experiments.

Cooperative multi-robot observation of multiple moving targets

International Nuclear Information System (INIS)

Parker, L.E.; Emmons, B.A.

1997-01-01

An important issue that arises in the automation of many security, surveillance, and reconnaissance tasks is that of monitoring, or observing, the movements of targets navigating in a bounded area of interest. A key research issue in these problems is that of sensor placement--determining where sensors should be located to maintain the targets in view. In complex applications of this type, the use of multiple sensors dynamically moving over time is required. In this paper, the authors investigate the sue of a cooperative team of autonomous sensor-based robots for multi-robot observation of multiple moving targets. They focus primarily on developing the distributed control strategies that allow the robot team to attempt to maximize the collective tie during which each object is being observed by at least one robot in the area of interest. The initial efforts in this problem address the aspects of distributed control in homogeneous robot teams with equivalent sensing and movement capabilities working in an uncluttered, bounded area. This paper first formalizes the problem, discusses related work, and then shows that this problem is NP-hard. They then present a distributed approximate approach to solving this problem that combines low-level multi-robot control with higher-level control

Dynamical Behavior of Multi-Robot Systems Using Lattice Gas Automata

Energy Technology Data Exchange (ETDEWEB)

Cameron, S.M.; Robinett, R.; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

1999-03-11

Recent attention has been given to the deployment of an adaptable sensor array realized by multi-robotic systems. Our group has been studying the collective behavior of autonomous, multi-agent systems and their applications in the area of remote-sensing and emerging threats. To accomplish such tasks, an interdisciplinary research effort at Sandia National Laboratories are conducting tests in the fields of sensor technology, robotics, and multi-robotic and multi-agents architectures. Our goal is to coordinate a constellation of point sensors that optimizes spatial coverage and multivariate signal analysis using unmanned robotic vehicles (e.g., RATLERs, Robotic All-ten-sin Lunar Exploration Rover-class vehicles). Overall design methodology is to evolve complex collective behaviors realized through simple interaction (kinetic) physics and artificial intelligence to enable real-time operational responses to emerging threats. This paper focuses on our recent work understanding the dynamics of many-body systems using the physics-based hydrodynamic model of lattice gas automata. Three design features are investigated. One, for single-speed robots, a hexagonal nearest-neighbor interaction topology is necessary to preserve standard hydrodynamic flow. Two, adaptability, defined by the swarm's deformation rate, can be controlled through the hydrodynamic viscosity term, which, in turn, is defined by the local robotic interaction rules. Three, due to the inherent non-linearity of the dynamical equations describing large ensembles, development of stability criteria ensuring convergence to equilibrium states is developed by scaling information flow rates relative to a swarm's hydrodynamic flow rate. An initial test case simulates a swarm of twenty-five robots that maneuvers past an obstacle while following a moving target. A genetic algorithm optimizes applied nearest-neighbor forces in each of five spatial regions distributed over the simulation domain. Armed with

Parallel Execution of Multi Set Constraint Rewrite Rules

DEFF Research Database (Denmark)

Sulzmann, Martin; Lam, Edmund Soon Lee

2008-01-01

that the underlying constraint rewrite implementation executes rewrite steps in parallel on increasingly popular becoming multi-core architectures. We design and implement efficient algorithms which allow for the parallel execution of multi-set constraint rewrite rules. Our experiments show that we obtain some......Multi-set constraint rewriting allows for a highly parallel computational model and has been used in a multitude of application domains such as constraint solving, agent specification etc. Rewriting steps can be applied simultaneously as long as they do not interfere with each other.We wish...

Design of parallel intersector weld/cut robot for machining processes in ITER vacuum vessel

International Nuclear Information System (INIS)

Wu Huapeng; Handroos, Heikki; Kovanen, Janne; Rouvinen, Asko; Hannukainen, Petri; Saira, Tanja; Jones, Lawrence

2003-01-01

This paper presents a new parallel robot Penta-WH, which has five degrees of freedom driven by hydraulic cylinders. The manipulator has a large, singularity-free workspace and high stiffness and it acts as a transport device for welding, machining and inspection end-effectors inside the ITER vacuum vessel. The presented kinematic structure of a parallel robot is particularly suitable for the ITER environment. Analysis of the machining process for ITER, such as the machining methods and forces are given, and the kinematic analyses, such as workspace and force capacity are discussed

Multi-robot Task Allocation for Search and Rescue Missions

International Nuclear Information System (INIS)

Hussein, Ahmed; Adel, Mohamed; Bakr, Mohamed; Shehata, Omar M; Khamis, Alaa

2014-01-01

Many researchers from academia and industry are attracted to investigate how to design and develop robust versatile multi-robot systems by solving a number of challenging and complex problems such as task allocation, group formation, self-organization and much more. In this study, the problem of multi-robot task allocation (MRTA) is tackled. MRTA is the problem of optimally allocating a set of tasks to a group of robots to optimize the overall system performance while being subjected to a set of constraints. A generic market-based approach is proposed in this paper to solve this problem. The efficacy of the proposed approach is quantitatively evaluated through simulation and real experimentation using heterogeneous Khepera-III mobile robots. The results from both simulation and experimentation indicate the high performance of the proposed algorithms and their applicability in search and rescue missions

Octopus-inspired multi-arm robotic swimming.

Science.gov (United States)

Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

2015-05-13

The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems.

Kinematics modeling and experimentation of the multi-manipulator tooth-arrangement robot for full denture manufacturing.

Science.gov (United States)

Zhang, Yong-de; Jiang, Jin-gang; Liang, Ting; Hu, Wei-ping

2011-12-01

Artificial teeth are very complicated in shape, and not easy to be grasped and manipulated accurately by a single robot. The method of tooth-arrangement by multi-manipulator for complete denture manufacturing proposed in this paper. A novel complete denture manufacturing mechanism is designed based on multi-manipulator and dental arch generator. Kinematics model of the multi-manipulator tooth-arrangement robot is built by analytical method based on tooth-arrangement principle for full denture. Preliminary experiments on tooth-arrangement are performed using the multi-manipulator tooth-arrangement robot prototype system. The multi-manipulator tooth-arrangement robot prototype system can automatically design and manufacture a set of complete denture that is suitable for a patient according to the jaw arch parameters. The experimental results verified the validity of kinematics model of the multi-manipulator tooth-arrangement robot and the feasibility of the manufacture strategy of complete denture fulfilled by multi-manipulator tooth-arrangement robot.

Grasp planning for a reconfigurable parallel robot with an underactuated arm structure

Directory of Open Access Journals (Sweden)

M. Riedel

2010-12-01

Full Text Available In this paper, a novel approach of grasp planning is applied to find out the appropriate grasp points for a reconfigurable parallel robot called PARAGRIP (Parallel Gripping. This new handling system is able to manipulate objects in the six-dimensional Cartesian space by several robotic arms using only six actuated joints. After grasping, the contact elements at the end of the underactuated arm mechanisms are connected to the object which forms a closed loop mechanism similar to the architecture of parallel manipulators. As the mounting and grasp points of the arms can easily be changed, the manipulator can be reconfigured to match the user's preferences and needs. This paper raises the question, how and where these grasp points are to be placed on the object to perform well for a certain manipulation task.

This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010, 19 August 2010, Montréal, Canada.

State-space Generalized Predicitve Control for redundant parallel robots

Czech Academy of Sciences Publication Activity Database

Belda, Květoslav; Böhm, Josef; Valášek, M.

2003-01-01

Roč. 31, č. 3 (2003), s. 413-432 ISSN 1539-7734 R&D Projects: GA ČR GA101/03/0620 Grant - others:CTU(CZ) 0204512 Institutional research plan: CEZ:AV0Z1075907 Keywords : parallel robot construction * generalized predictive control * drive redundancy Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/historie/belda-0411126.pdf

Development of a Survivable Cloud Multi-Robot Framework for Heterogeneous Environments

Directory of Open Access Journals (Sweden)

Isaac Osunmakinde

2014-10-01

Full Text Available Cloud robotics is a paradigm that allows for robots to offload computationally intensive and data storage requirements into the cloud by providing a secure and customizable environment. The challenge for cloud robotics is the inherent problem of cloud disconnection. A major assumption made in the development of the current cloud robotics frameworks is that the connection between the cloud and the robot is always available. However, for multi-robots working in heterogeneous environments, the connection between the cloud and the robots cannot always be guaranteed. This work serves to assist with the challenge of disconnection in cloud robotics by proposing a survivable cloud multi-robotics (SCMR framework for heterogeneous environments. The SCMR framework leverages the combination of a virtual ad hoc network formed by robot-to-robot communication and a physical cloud infrastructure formed by robot-to-cloud communications. The quality of service (QoS on the SCMR framework was tested and validated by determining the optimal energy utilization and time of response (ToR on drivability analysis with and without cloud connection. The design trade-off, including the result, is between the computation energy for the robot execution and the offloading energy for the cloud execution.

Dynamic modelling of a 3-CPU parallel robot via screw theory

Directory of Open Access Journals (Sweden)

L. Carbonari

2013-04-01

Full Text Available The article describes the dynamic modelling of I.Ca.Ro., a novel Cartesian parallel robot recently designed and prototyped by the robotics research group of the Polytechnic University of Marche. By means of screw theory and virtual work principle, a computationally efficient model has been built, with the final aim of realising advanced model based controllers. Then a dynamic analysis has been performed in order to point out possible model simplifications that could lead to a more efficient run time implementation.

Proposed Methodology for Application of Human-like gradual Multi-Agent Q-Learning (HuMAQ) for Multi-robot Exploration

International Nuclear Information System (INIS)

Ray, Dip Narayan; Majumder, Somajyoti

2014-01-01

Several attempts have been made by the researchers around the world to develop a number of autonomous exploration techniques for robots. But it has been always an important issue for developing the algorithm for unstructured and unknown environments. Human-like gradual Multi-agent Q-leaming (HuMAQ) is a technique developed for autonomous robotic exploration in unknown (and even unimaginable) environments. It has been successfully implemented in multi-agent single robotic system. HuMAQ uses the concept of Subsumption architecture, a well-known Behaviour-based architecture for prioritizing the agents of the multi-agent system and executes only the most common action out of all the different actions recommended by different agents. Instead of using new state-action table (Q-table) each time, HuMAQ uses the immediate past table for efficient and faster exploration. The proof of learning has also been established both theoretically and practically. HuMAQ has the potential to be used in different and difficult situations as well as applications. The same architecture has been modified to use for multi-robot exploration in an environment. Apart from all other existing agents used in the single robotic system, agents for inter-robot communication and coordination/ co-operation with the other similar robots have been introduced in the present research. Current work uses a series of indigenously developed identical autonomous robotic systems, communicating with each other through ZigBee protocol

Characterization of robotics parallel algorithms and mapping onto a reconfigurable SIMD machine

Science.gov (United States)

Lee, C. S. G.; Lin, C. T.

1989-01-01

The kinematics, dynamics, Jacobian, and their corresponding inverse computations are six essential problems in the control of robot manipulators. Efficient parallel algorithms for these computations are discussed and analyzed. Their characteristics are identified and a scheme on the mapping of these algorithms to a reconfigurable parallel architecture is presented. Based on the characteristics including type of parallelism, degree of parallelism, uniformity of the operations, fundamental operations, data dependencies, and communication requirement, it is shown that most of the algorithms for robotic computations possess highly regular properties and some common structures, especially the linear recursive structure. Moreover, they are well-suited to be implemented on a single-instruction-stream multiple-data-stream (SIMD) computer with reconfigurable interconnection network. The model of a reconfigurable dual network SIMD machine with internal direct feedback is introduced. A systematic procedure internal direct feedback is introduced. A systematic procedure to map these computations to the proposed machine is presented. A new scheduling problem for SIMD machines is investigated and a heuristic algorithm, called neighborhood scheduling, that reorders the processing sequence of subtasks to reduce the communication time is described. Mapping results of a benchmark algorithm are illustrated and discussed.

An Approach to Evaluate Stability for Cable-Based Parallel Camera Robots with Hybrid Tension-Stiffness Properties

Directory of Open Access Journals (Sweden)

Huiling Wei

2015-12-01

Full Text Available This paper focuses on studying the effect of cable tensions and stiffness on the stability of cable-based parallel camera robots. For this purpose, the tension factor and the stiffness factor are defined, and the expression of stability is deduced. A new approach is proposed to calculate the hybrid-stability index with the minimum cable tension and the minimum singular value. Firstly, the kinematic model of a cable-based parallel camera robot is established. Based on the model, the tensions are solved and a tension factor is defined. In order to obtain the tension factor, an optimization of the cable tensions is carried out. Then, an expression of the system's stiffness is deduced and a stiffness factor is defined. Furthermore, an approach to evaluate the stability of the cable-based camera robots with hybrid tension-stiffness properties is presented. Finally, a typical three-degree-of-freedom cable-based parallel camera robot with four cables is studied as a numerical example. The simulation results show that the approach is both reasonable and effective.

Continuum Reconfigurable Parallel Robots for Surgery: Shape Sensing and State Estimation with Uncertainty.

Science.gov (United States)

Anderson, Patrick L; Mahoney, Arthur W; Webster, Robert J

2017-07-01

This paper examines shape sensing for a new class of surgical robot that consists of parallel flexible structures that can be reconfigured inside the human body. Known as CRISP robots, these devices provide access to the human body through needle-sized entry points, yet can be configured into truss-like structures capable of dexterous movement and large force application. They can also be reconfigured as needed during a surgical procedure. Since CRISP robots are elastic, they will deform when subjected to external forces or other perturbations. In this paper, we explore how to combine sensor information with mechanics-based models for CRISP robots to estimate their shapes under applied loads. The end result is a shape sensing framework for CRISP robots that will enable future research on control under applied loads, autonomous motion, force sensing, and other robot behaviors.

Chained Iron Microparticles for Directionally Controlled Actuation of Soft Robots.

Science.gov (United States)

Schmauch, Marissa M; Mishra, Sumeet R; Evans, Benjamin A; Velev, Orlin D; Tracy, Joseph B

2017-04-05

Magnetic field-directed self-assembly of magnetic particles in chains is useful for developing directionally responsive materials for applications in soft robotics. Using materials with greater complexity allows advanced functions, while still using simple device architectures. Elastomer films containing chained magnetic microparticles were prepared through solvent casting and formed into magnetically actuated lifters, accordions, valves, and pumps. Chaining both enhances actuation and imparts a directional response. Cantilevers used as lifters were able to lift up to 50 times the mass of the polymer film. We introduce the "specific torque", the torque per field per mass of magnetic particles, as a figure of merit for assessing and comparing the performance of lifters and related devices. Devices in this work generated specific torques of 68 Nm/kgT, which is significantly higher than in previously reported actuators. Applying magnetic fields to folded accordion structures caused extension and compression, depending on the accordion's orientation. In peristaltic pumps comprised of composite tubes containing embedded chains, magnetic fields caused a section of the tube to pinch closed where the field was applied. These results will facilitate both the further development of soft robots based on chained magnetic particles and efforts to engineer materials with higher specific torque.

Direct kinematics solution architectures for industrial robot manipulators: Bit-serial versus parallel

Science.gov (United States)

Lee, J.; Kim, K.

1991-01-01

A Very Large Scale Integration (VLSI) architecture for robot direct kinematic computation suitable for industrial robot manipulators was investigated. The Denavit-Hartenberg transformations are reviewed to exploit a proper processing element, namely an augmented CORDIC. Specifically, two distinct implementations are elaborated on, such as the bit-serial and parallel. Performance of each scheme is analyzed with respect to the time to compute one location of the end-effector of a 6-links manipulator, and the number of transistors required.

Direct kinematics solution architectures for industrial robot manipulators: Bit-serial versus parallel

Science.gov (United States)

Lee, J.; Kim, K.

A Very Large Scale Integration (VLSI) architecture for robot direct kinematic computation suitable for industrial robot manipulators was investigated. The Denavit-Hartenberg transformations are reviewed to exploit a proper processing element, namely an augmented CORDIC. Specifically, two distinct implementations are elaborated on, such as the bit-serial and parallel. Performance of each scheme is analyzed with respect to the time to compute one location of the end-effector of a 6-links manipulator, and the number of transistors required.

Scalable Task Assignment for Heterogeneous Multi-Robot Teams

Directory of Open Access Journals (Sweden)

Paula García

2013-02-01

Full Text Available This work deals with the development of a dynamic task assignment strategy for heterogeneous multi-robot teams in typical real world scenarios. The strategy must be efficiently scalable to support problems of increasing complexity with minimum designer intervention. To this end, we have selected a very simple auction-based strategy, which has been implemented and analysed in a multi-robot cleaning problem that requires strong coordination and dynamic complex subtask organization. We will show that the selection of a simple auction strategy provides a linear computational cost increase with the number of robots that make up the team and allows the solving of highly complex assignment problems in dynamic conditions by means of a hierarchical sub-auction policy. To coordinate and control the team, a layered behaviour-based architecture has been applied that allows the reusing of the auction-based strategy to achieve different coordination levels.

An Adaptive Multi-Objective Particle Swarm Optimization Algorithm for Multi-Robot Path Planning

Directory of Open Access Journals (Sweden)

Nizar Hadi Abbas

2016-07-01

Full Text Available This paper discusses an optimal path planning algorithm based on an Adaptive Multi-Objective Particle Swarm Optimization Algorithm (AMOPSO for two case studies. First case, single robot wants to reach a goal in the static environment that contain two obstacles and two danger source. The second one, is improving the ability for five robots to reach the shortest way. The proposed algorithm solves the optimization problems for the first case by finding the minimum distance from initial to goal position and also ensuring that the generated path has a maximum distance from the danger zones. And for the second case, finding the shortest path for every robot and without any collision between them with the shortest time. In order to evaluate the proposed algorithm in term of finding the best solution, six benchmark test functions are used to make a comparison between AMOPSO and the standard MOPSO. The results show that the AMOPSO has a better ability to get away from local optimums with a quickest convergence than the MOPSO. The simulation results using Matlab 2014a, indicate that this methodology is extremely valuable for every robot in multi-robot framework to discover its own particular proper pa‌th from the start to the destination position with minimum distance and time.

Design and implementation of a novel modal space active force control concept for spatial multi-DOF parallel robotic manipulators actuated by electrical actuators.

Science.gov (United States)

Yang, Chifu; Zhao, Jinsong; Li, Liyi; Agrawal, Sunil K

2018-01-01

Robotic spine brace based on parallel-actuated robotic system is a new device for treatment and sensing of scoliosis, however, the strong dynamic coupling and anisotropy problem of parallel manipulators result in accuracy loss of rehabilitation force control, including big error in direction and value of force. A novel active force control strategy named modal space force control is proposed to solve these problems. Considering the electrical driven system and contact environment, the mathematical model of spatial parallel manipulator is built. The strong dynamic coupling problem in force field is described via experiments as well as the anisotropy problem of work space of parallel manipulators. The effects of dynamic coupling on control design and performances are discussed, and the influences of anisotropy on accuracy are also addressed. With mass/inertia matrix and stiffness matrix of parallel manipulators, a modal matrix can be calculated by using eigenvalue decomposition. Making use of the orthogonality of modal matrix with mass matrix of parallel manipulators, the strong coupled dynamic equations expressed in work space or joint space of parallel manipulator may be transformed into decoupled equations formulated in modal space. According to this property, each force control channel is independent of others in the modal space, thus we proposed modal space force control concept which means the force controller is designed in modal space. A modal space active force control is designed and implemented with only a simple PID controller employed as exampled control method to show the differences, uniqueness, and benefits of modal space force control. Simulation and experimental results show that the proposed modal space force control concept can effectively overcome the effects of the strong dynamic coupling and anisotropy problem in the physical space, and modal space force control is thus a very useful control framework, which is better than the current joint

Design and Control System of a Modular Parallel Robot for Medical Applications

Directory of Open Access Journals (Sweden)

Florin Covaciu

2015-06-01

Full Text Available Brachytherapy (BT, a cancer treatment method, is a type of internal radiation therapy which implies that radiation doses (seeds are placed inside the tumor, aiming to destroy only the cancerous cells, without affecting the surrounding healthy tissue. For a successful brachytherapy procedure, the accurate radiation seeds placement is an important issue, which is why a robotic system has been built for this task. The paper presents the design of a parallel robotic system for brachytherapy procedures and the control system architecture and its implementation.

Development of structural schemes of parallel structure manipulators using screw calculus

Science.gov (United States)

Rashoyan, G. V.; Shalyukhin, K. A.; Gaponenko, EV

2018-03-01

The paper considers the approach to the structural analysis and synthesis of parallel structure robots based on the mathematical apparatus of groups of screws and on a concept of reciprocity of screws. The results are depicted of synthesis of parallel structure robots with different numbers of degrees of freedom, corresponding to the different groups of screws. Power screws are applied with this aim, based on the principle of static-kinematic analogy; the power screws are similar to the orts of axes of not driven kinematic pairs of a corresponding connecting chain. Accordingly, kinematic screws of the outlet chain of a robot are simultaneously determined which are reciprocal to power screws of kinematic sub-chains. Solution of certain synthesis problems is illustrated with practical applications. Closed groups of screws can have eight types. The three-membered groups of screws are of greatest significance, as well as four-membered screw groups [1] and six-membered screw groups. Three-membered screw groups correspond to progressively guiding mechanisms, to spherical mechanisms, and to planar mechanisms. The four-membered group corresponds to the motion of the SCARA robot. The six-membered group includes all possible motions. From the works of A.P. Kotelnikov, F.M. Dimentberg, it is known that closed fifth-order screw groups do not exist. The article presents examples of the mechanisms corresponding to the given groups.

A Multi-Agent Control Architecture for a Robotic Wheelchair

Directory of Open Access Journals (Sweden)

C. Galindo

2006-01-01

Full Text Available Assistant robots like robotic wheelchairs can perform an effective and valuable work in our daily lives. However, they eventually may need external help from humans in the robot environment (particularly, the driver in the case of a wheelchair to accomplish safely and efficiently some tricky tasks for the current technology, i.e. opening a locked door, traversing a crowded area, etc. This article proposes a control architecture for assistant robots designed under a multi-agent perspective that facilitates the participation of humans into the robotic system and improves the overall performance of the robot as well as its dependability. Within our design, agents have their own intentions and beliefs, have different abilities (that include algorithmic behaviours and human skills and also learn autonomously the most convenient method to carry out their actions through reinforcement learning. The proposed architecture is illustrated with a real assistant robot: a robotic wheelchair that provides mobility to impaired or elderly people.

A formation control strategy with coupling weights for the multi-robot system

Science.gov (United States)

Liang, Xudong; Wang, Siming; Li, Weijie

2017-12-01

The distributed formation problem of the multi-robot system with general linear dynamic characteristics and directed communication topology is discussed. In order to avoid that the multi-robot system can not maintain the desired formation in the complex communication environment, the distributed cooperative algorithm with coupling weights based on zipf distribution is designed. The asymptotic stability condition for the formation of the multi-robot system is given, and the theory of the graph and the Lyapunov theory are used to prove that the formation can converge to the desired geometry formation and the desired motion rules of the virtual leader under this condition. Nontrivial simulations are performed to validate the effectiveness of the distributed cooperative algorithm with coupling weights.

Multi-robots to micro-surgery: Selected robotic applications at Sandia National Laboratories

Energy Technology Data Exchange (ETDEWEB)

Bennett, P.C. [Sandia National Labs., Albuquerque, NM (United States). Intelligent Systems and Robotics Center

1996-11-01

The Intelligent Systems and Robotics Center (ISRC) at Sandia National Laboratories is a multi-program organization, pursuing research, development and applications in a wide range of field. Activities range from large-scale applications such as nuclear facility dismantlement for the US Department of Energy (DOE), to aircraft inspection and refurbishment, to automated script and program generation for robotic manufacturing and assembly, to miniature robotic devices and sensors for remote sensing and micro-surgery. This paper describes six activities in the large and small scale that are underway and either nearing technology transfer stage or seeking industrial partners to continue application development. The topics of the applications include multiple arm coordination for intuitively maneuvering large, ungainly work pieces; simulation, analysis and graphical training capability for CP-5 research reactor dismantlement; miniature robots with volumes of 16 cubic centimeters and less developed for inspection and sensor deployment; and biomedical sensors to enhance automated prosthetic device production and fill laparoscopic surgery information gap.

Towards Human-Friendly Efficient Control of Multi-Robot Teams

Science.gov (United States)

Stoica, Adrian; Theodoridis, Theodoros; Barrero, David F.; Hu, Huosheng; McDonald-Maiers, Klaus

2013-01-01

This paper explores means to increase efficiency in performing tasks with multi-robot teams, in the context of natural Human-Multi-Robot Interfaces (HMRI) for command and control. The motivating scenario is an emergency evacuation by a transport convoy of unmanned ground vehicles (UGVs) that have to traverse, in shortest time, an unknown terrain. In the experiments the operator commands, in minimal time, a group of rovers through a maze. The efficiency of performing such tasks depends on both, the levels of robots' autonomy, and the ability of the operator to command and control the team. The paper extends the classic framework of levels of autonomy (LOA), to levels/hierarchy of autonomy characteristic of Groups (G-LOA), and uses it to determine new strategies for control. An UGVoriented command language (UGVL) is defined, and a mapping is performed from the human-friendly gesture-based HMRI into the UGVL. The UGVL is used to control a team of 3 robots, exploring the efficiency of different G-LOA; specifically, by (a) controlling each robot individually through the maze, (b) controlling a leader and cloning its controls to followers, and (c) controlling the entire group. Not surprisingly, commands at increased G-LOA lead to a faster traverse, yet a number of aspects are worth discussing in this context.

Conceptual design and kinematic analysis of a novel parallel robot for high-speed pick-and-place operations

Science.gov (United States)

Meng, Qizhi; Xie, Fugui; Liu, Xin-Jun

2018-06-01

This paper deals with the conceptual design, kinematic analysis and workspace identification of a novel four degrees-of-freedom (DOFs) high-speed spatial parallel robot for pick-and-place operations. The proposed spatial parallel robot consists of a base, four arms and a 1½ mobile platform. The mobile platform is a major innovation that avoids output singularity and offers the advantages of both single and double platforms. To investigate the characteristics of the robot's DOFs, a line graph method based on Grassmann line geometry is adopted in mobility analysis. In addition, the inverse kinematics is derived, and the constraint conditions to identify the correct solution are also provided. On the basis of the proposed concept, the workspace of the robot is identified using a set of presupposed parameters by taking input and output transmission index as the performance evaluation criteria.

The Emergence of Multi-Cellular Robot Organisms through On-line On-board Evolution

NARCIS (Netherlands)

Weel, B.P.M.; Haasdijk, E.W.; Eiben, A.E.

2012-01-01

We investigate whether a swarm of robots can evolve controllers that cause aggregation into 'multi-cellular' robot organisms without a specific reward to do so. To this end, we create a world where aggregated robots receive more energy than individual ones and enable robots to evolve their

An intelligent space for mobile robot localization using a multi-camera system.

Science.gov (United States)

Rampinelli, Mariana; Covre, Vitor Buback; de Queiroz, Felippe Mendonça; Vassallo, Raquel Frizera; Bastos-Filho, Teodiano Freire; Mazo, Manuel

2014-08-15

This paper describes an intelligent space, whose objective is to localize and control robots or robotic wheelchairs to help people. Such an intelligent space has 11 cameras distributed in two laboratories and a corridor. The cameras are fixed in the environment, and image capturing is done synchronously. The system was programmed as a client/server with TCP/IP connections, and a communication protocol was defined. The client coordinates the activities inside the intelligent space, and the servers provide the information needed for that. Once the cameras are used for localization, they have to be properly calibrated. Therefore, a calibration method for a multi-camera network is also proposed in this paper. A robot is used to move a calibration pattern throughout the field of view of the cameras. Then, the captured images and the robot odometry are used for calibration. As a result, the proposed algorithm provides a solution for multi-camera calibration and robot localization at the same time. The intelligent space and the calibration method were evaluated under different scenarios using computer simulations and real experiments. The results demonstrate the proper functioning of the intelligent space and validate the multi-camera calibration method, which also improves robot localization.

An Intelligent Space for Mobile Robot Localization Using a Multi-Camera System

Directory of Open Access Journals (Sweden)

Mariana Rampinelli

2014-08-01

Full Text Available This paper describes an intelligent space, whose objective is to localize and control robots or robotic wheelchairs to help people. Such an intelligent space has 11 cameras distributed in two laboratories and a corridor. The cameras are fixed in the environment, and image capturing is done synchronously. The system was programmed as a client/server with TCP/IP connections, and a communication protocol was defined. The client coordinates the activities inside the intelligent space, and the servers provide the information needed for that. Once the cameras are used for localization, they have to be properly calibrated. Therefore, a calibration method for a multi-camera network is also proposed in this paper. A robot is used to move a calibration pattern throughout the field of view of the cameras. Then, the captured images and the robot odometry are used for calibration. As a result, the proposed algorithm provides a solution for multi-camera calibration and robot localization at the same time. The intelligent space and the calibration method were evaluated under different scenarios using computer simulations and real experiments. The results demonstrate the proper functioning of the intelligent space and validate the multi-camera calibration method, which also improves robot localization.

Identification of human intestinal parasites affecting an asymptomatic peri-urban Argentinian population using multi-parallel quantitative real-time polymerase chain reaction.

Science.gov (United States)

Cimino, Rubén O; Jeun, Rebecca; Juarez, Marisa; Cajal, Pamela S; Vargas, Paola; Echazú, Adriana; Bryan, Patricia E; Nasser, Julio; Krolewiecki, Alejandro; Mejia, Rojelio

2015-07-17

In resource-limited countries, stool microscopy is the diagnostic test of choice for intestinal parasites (soil-transmitted helminths and/or intestinal protozoa). However, sensitivity and specificity is low. Improved diagnosis of intestinal parasites is especially important for accurate measurements of prevalence and intensity of infections in endemic areas. The study was carried out in Orán, Argentina. A total of 99 stool samples from a local surveillance campaign were analyzed by concentration microscopy and McMaster egg counting technique compared to the analysis by multi-parallel quantitative real-time polymerase chain reaction (qPCR). This study compared the performance of qPCR assay and stool microscopy for 8 common intestinal parasites that infect humans including the helminths Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, and the protozoa Giardia lamblia, Cryptosporidium parvum/hominis, and Entamoeba histolytica, and investigated the prevalence of polyparasitism in an endemic area. qPCR showed higher detection rates for all parasites as compared to stool microscopy except T. trichiura. Species-specific primers and probes were able to distinguish between A. duodenale (19.1%) and N. americanus (36.4%) infections. There were 48.6% of subjects co-infected with both hookworms, and a significant increase in hookworm DNA for A. duodenale versus N. americanus (119.6 fg/μL: 0.63 fg/μL, P parasites in an endemic area that has improved diagnostic accuracy compared to stool microscopy. This first time use of multi-parallel qPCR in Argentina has demonstrated the high prevalence of intestinal parasites in a peri-urban area. These results will contribute to more accurate epidemiological survey, refined treatment strategies on a public scale, and better health outcomes in endemic settings.

Towards Real-Time Distributed Planning in Multi-Robot Systems

KAUST Repository

Abdelkader, Mohamed

2018-04-01

Recently, there has been an increasing interest in robotics related to multi-robot applications. Such systems can be involved in several tasks such as collaborative search and rescue, aerial transportation, surveillance, and monitoring, to name a few. There are two possible architectures for the autonomous control of multi-robot systems. In the centralized architecture, a master controller communicates with all the robots to collect information. It uses this information to make decisions for the entire system and then sends commands to each robot. In contrast, in the distributed architecture, each robot makes its own decision independent from a central authority. While distributed architecture is a more portable solution, it comes at the expense of extensive information exchange (communication). The extensive communication between robots can result in decision delays because of which distributed architecture is often impractical for systems with strict real-time constraints, e.g. when decisions have to be taken in the order of milliseconds. In this thesis, we propose a distributed framework that strikes a balance between limited communicated information and reasonable system-wide performance while running in real-time. We implement the proposed approach in a game setting of two competing teams of drones, defenders and attackers. Defending drones execute a proposed linear program algorithm (using only onboard computing modules) to obstruct attackers from infiltrating a defense zone while having minimal local message passing. Another main contribution is that we developed a realistic simulation environment as well as lab and outdoor hardware setups of customized drones for testing the system in realistic scenarios. Our software is completely open-source and fully integrated with the well-known Robot Operating System (ROS) in hopes to make our work easily reproducible and for rapid future improvements.

Particularities of fully-parallel manipulators in 6-DOFs robots design: a review of critical aspects

Directory of Open Access Journals (Sweden)

Milica Lucian

2017-01-01

Full Text Available A whole range of industrial applications requires the presence of parallel mechanisms with six degrees of freedom (6-DOF which have been developed in the last fifteen years, and one of the reasons why they still are a current topic is that present-day computers are capable of performing real-time motion laws of great complexity associated with these types of parallel mechanisms. The present work underlines particularities of parallel manipulators and their importance in the design of 6-DOF robots. The paper reveals the progress made in the last twenty years in the development of 6-DOF parallel manipulators, which increasingly find a wide scope of applications in different industrial areas such as robotics, manufacture and assisted medicine. It also emphasizes the need to determine singular configurations and the effect of cinematic redundancy which can increase the working space of the manipulators by adding active joints in one or more branches of the manipulator. Throughout the work, there were outlined three types of singularities encountered in the modelling of different types of parallel manipulators, and three types of redundancy. Furthermore, an analysis was made of the dimension of the workspace for a series of parallel manipulators, highlighting a number of factors that influence its size.

Foraging behavior analysis of swarm robotics system

Directory of Open Access Journals (Sweden)

Sakthivelmurugan E.

2018-01-01

Full Text Available Swarm robotics is a number of small robots that are synchronically works together to accomplish a given task. Swarm robotics faces many problems in performing a given task. The problems are pattern formation, aggregation, Chain formation, self-assembly, coordinated movement, hole avoidance, foraging and self-deployment. Foraging is most essential part in swarm robotics. Foraging is the task to discover the item and get back into the shell. The researchers conducted foraging experiments with random-movement of robots and they have end up with unique solutions. Most of the researchers have conducted experiments using the circular arena. The shell is placed at the centre of the arena and environment boundary is well known. In this study, an attempt is made to different strategic movements like straight line approach, parallel line approach, divider approach, expanding square approach, and parallel sweep approach. All these approaches are to be simulated by using player/stage open-source simulation software based on C and C++ programming language in Linux operating system. Finally statistical comparison will be done with task completion time of all these strategies using ANOVA to identify the significant searching strategy.

A 6-DOF parallel bone-grinding robot for cervical disc replacement surgery.

Science.gov (United States)

Tian, Heqiang; Wang, Chenchen; Dang, Xiaoqing; Sun, Lining

2017-12-01

Artificial cervical disc replacement surgery has become an effective and main treatment method for cervical disease, which has become a more common and serious problem for people with sedentary work. To improve cervical disc replacement surgery significantly, a 6-DOF parallel bone-grinding robot is developed for cervical bone-grinding by image navigation and surgical plan. The bone-grinding robot including mechanical design and low level control is designed. The bone-grinding robot navigation is realized by optical positioning with spatial registration coordinate system defined. And a parametric robot bone-grinding plan and high level control have been developed for plane grinding for cervical top endplate and tail endplate grinding by a cylindrical grinding drill and spherical grinding for two articular surfaces of bones by a ball grinding drill. Finally, the surgical flow for a robot-assisted cervical disc replacement surgery procedure is present. The final experiments results verified the key technologies and performance of the robot-assisted surgery system concept excellently, which points out a promising clinical application with higher operability. Finally, study innovations, study limitations, and future works of this present study are discussed, and conclusions of this paper are also summarized further. This bone-grinding robot is still in the initial stage, and there are many problems to be solved from a clinical point of view. Moreover, the technique is promising and can give a good support for surgeons in future clinical work.

Multi-agent robotic systems and applications for satellite missions

Science.gov (United States)

Nunes, Miguel A.

A revolution in the space sector is happening. It is expected that in the next decade there will be more satellites launched than in the previous sixty years of space exploration. Major challenges are associated with this growth of space assets such as the autonomy and management of large groups of satellites, in particular with small satellites. There are two main objectives for this work. First, a flexible and distributed software architecture is presented to expand the possibilities of spacecraft autonomy and in particular autonomous motion in attitude and position. The approach taken is based on the concept of distributed software agents, also referred to as multi-agent robotic system. Agents are defined as software programs that are social, reactive and proactive to autonomously maximize the chances of achieving the set goals. Part of the work is to demonstrate that a multi-agent robotic system is a feasible approach for different problems of autonomy such as satellite attitude determination and control and autonomous rendezvous and docking. The second main objective is to develop a method to optimize multi-satellite configurations in space, also known as satellite constellations. This automated method generates new optimal mega-constellations designs for Earth observations and fast revisit times on large ground areas. The optimal satellite constellation can be used by researchers as the baseline for new missions. The first contribution of this work is the development of a new multi-agent robotic system for distributing the attitude determination and control subsystem for HiakaSat. The multi-agent robotic system is implemented and tested on the satellite hardware-in-the-loop testbed that simulates a representative space environment. The results show that the newly proposed system for this particular case achieves an equivalent control performance when compared to the monolithic implementation. In terms on computational efficiency it is found that the multi

Optimization Design by Genetic Algorithm Controller for Trajectory Control of a 3-RRR Parallel Robot

Directory of Open Access Journals (Sweden)

Lianchao Sheng

2018-01-01

Full Text Available In order to improve the control precision and robustness of the existing proportion integration differentiation (PID controller of a 3-Revolute–Revolute–Revolute (3-RRR parallel robot, a variable PID parameter controller optimized by a genetic algorithm controller is proposed in this paper. Firstly, the inverse kinematics model of the 3-RRR parallel robot was established according to the vector method, and the motor conversion matrix was deduced. Then, the error square integral was chosen as the fitness function, and the genetic algorithm controller was designed. Finally, the control precision of the new controller was verified through the simulation model of the 3-RRR planar parallel robot—built in SimMechanics—and the robustness of the new controller was verified by adding interference. The results show that compared with the traditional PID controller, the new controller designed in this paper has better control precision and robustness, which provides the basis for practical application.

Design, fabrication and characterization of a micro-fluxgate intended for parallel robot application

Science.gov (United States)

Kirchhoff, M. R.; Bogdanski, G.; Büttgenbach, S.

2009-05-01

This paper presents a micro-magnetometer based on the fluxgate principle. Fluxgates detect the magnitude and direction of DC and low-frequency AC magnetic fields. The detectable flux density typically ranges from several 10 nT to about 1 mT. The introduced fluxgate sensor is fabricated using MEMS-technologies, basically UV depth lithography and electroplating for manufacturing high aspect ratio structures. It consists of helical copper coils around a soft magnetic nickel-iron (NiFe) core. The core is designed in so-called racetrack geometry, whereby the directional sensitivity of the sensor is considerably higher compared to common ring-core fluxgates. The electrical operation is based on analyzing the 2nd harmonic of the AC output signal. Configuration, manufacturing and selected characteristics of the fluxgate magnetometer are discussed in this work. The fluxgate builds the basis of an innovative angular sensor system for a parallel robot with HEXA-structure. Integrated into the passive joints of the parallel robot, the fluxgates are combined with permanent magnets rotating on the joint shafts. The magnet transmits the angular information via its magnetic orientation. In this way, the angles between the kinematic elements are measured, which allows self-calibration of the robot and the fast analytical solution of direct kinematics for an advanced workspace monitoring.

Multi-physics modelling of a compliant humanoid robot

Energy Technology Data Exchange (ETDEWEB)

Zobova, Alexandra A., E-mail: azobova@mech.math.msu.su [Lomonosov Moscow State University, Faculty of Mechanics and Mathematics (Russian Federation); Habra, Timothée, E-mail: timothee.habra@uclouvain.be [Université catholique de Louvain (UCL), Center for Research in Mechatronics, Institute of Mechanics, Materials, and Civil Engineering (Belgium); Van der Noot, Nicolas, E-mail: nicolas.vandernoot@uclouvain.be, E-mail: nicolas.vandernoot@epfl.ch [EPFL STI IBI BIOROB, Biorobotics Laboratory, Institute of Bioengineering, École polytechnique fédérale de Lausanne (EPFL) (Switzerland); Dallali, Houman, E-mail: houman.dallali@iit.it; Tsagarakis, Nikolaos G., E-mail: nikos.tsagarakis@iit.it [Istituto Italiano di Tecnologia, Department of Advanced Robotics (Italy); Fisette, Paul, E-mail: paul.fisette@uclouvain.be; Ronsse, Renaud, E-mail: renaud.ronsse@uclouvain.be [Université catholique de Louvain (UCL), Center for Research in Mechatronics, Institute of Mechanics, Materials, and Civil Engineering (Belgium)

2017-01-15

We present a multibody simulator being used for compliant humanoid robot modelling and report our reasoning for choosing the settings of the simulator’s key features. First, we provide a study on how the numerical integration speed and accuracy depend on the coordinate representation of the multibody system. This choice is particularly critical for mechanisms with long serial chains (e.g. legs and arms). Our second contribution is a full electromechanical model of the inner dynamics of the compliant actuators embedded in the COMAN robot, since joints’ compliance is needed for the robot safety and energy efficiency. Third, we discuss the different approaches for modelling contacts and selecting an appropriate contact library. The recommended solution is to couple our simulator with an open-source contact library offering both accurate and fast contact modelling. The simulator performances are assessed by two different tasks involving contacts: a bimanual manipulation task and a squatting tasks. The former shows reliability of the simulator. For the latter, we report a comparison between the robot behaviour as predicted by our simulation environment, and the real one.

Multi-physics modelling of a compliant humanoid robot

International Nuclear Information System (INIS)

Zobova, Alexandra A.; Habra, Timothée; Van der Noot, Nicolas; Dallali, Houman; Tsagarakis, Nikolaos G.; Fisette, Paul; Ronsse, Renaud

2017-01-01

We present a multibody simulator being used for compliant humanoid robot modelling and report our reasoning for choosing the settings of the simulator’s key features. First, we provide a study on how the numerical integration speed and accuracy depend on the coordinate representation of the multibody system. This choice is particularly critical for mechanisms with long serial chains (e.g. legs and arms). Our second contribution is a full electromechanical model of the inner dynamics of the compliant actuators embedded in the COMAN robot, since joints’ compliance is needed for the robot safety and energy efficiency. Third, we discuss the different approaches for modelling contacts and selecting an appropriate contact library. The recommended solution is to couple our simulator with an open-source contact library offering both accurate and fast contact modelling. The simulator performances are assessed by two different tasks involving contacts: a bimanual manipulation task and a squatting tasks. The former shows reliability of the simulator. For the latter, we report a comparison between the robot behaviour as predicted by our simulation environment, and the real one.

Human-Robot Teaming in a Multi-Agent Space Assembly Task

Science.gov (United States)

Rehnmark, Fredrik; Currie, Nancy; Ambrose, Robert O.; Culbert, Christopher

2004-01-01

NASA's Human Space Flight program depends heavily on spacewalks performed by pairs of suited human astronauts. These Extra-Vehicular Activities (EVAs) are severely restricted in both duration and scope by consumables and available manpower. An expanded multi-agent EVA team combining the information-gathering and problem-solving skills of humans with the survivability and physical capabilities of robots is proposed and illustrated by example. Such teams are useful for large-scale, complex missions requiring dispersed manipulation, locomotion and sensing capabilities. To study collaboration modalities within a multi-agent EVA team, a 1-g test is conducted with humans and robots working together in various supporting roles.

Improving parallel imaging by jointly reconstructing multi-contrast data.

Science.gov (United States)

Bilgic, Berkin; Kim, Tae Hyung; Liao, Congyu; Manhard, Mary Kate; Wald, Lawrence L; Haldar, Justin P; Setsompop, Kawin

2018-08-01

To develop parallel imaging techniques that simultaneously exploit coil sensitivity encoding, image phase prior information, similarities across multiple images, and complementary k-space sampling for highly accelerated data acquisition. We introduce joint virtual coil (JVC)-generalized autocalibrating partially parallel acquisitions (GRAPPA) to jointly reconstruct data acquired with different contrast preparations, and show its application in 2D, 3D, and simultaneous multi-slice (SMS) acquisitions. We extend the joint parallel imaging concept to exploit limited support and smooth phase constraints through Joint (J-) LORAKS formulation. J-LORAKS allows joint parallel imaging from limited autocalibration signal region, as well as permitting partial Fourier sampling and calibrationless reconstruction. We demonstrate highly accelerated 2D balanced steady-state free precession with phase cycling, SMS multi-echo spin echo, 3D multi-echo magnetization-prepared rapid gradient echo, and multi-echo gradient recalled echo acquisitions in vivo. Compared to conventional GRAPPA, proposed joint acquisition/reconstruction techniques provide more than 2-fold reduction in reconstruction error. JVC-GRAPPA takes advantage of additional spatial encoding from phase information and image similarity, and employs different sampling patterns across acquisitions. J-LORAKS achieves a more parsimonious low-rank representation of local k-space by considering multiple images as additional coils. Both approaches provide dramatic improvement in artifact and noise mitigation over conventional single-contrast parallel imaging reconstruction. Magn Reson Med 80:619-632, 2018. © 2018 International Society for Magnetic Resonance in Medicine. © 2018 International Society for Magnetic Resonance in Medicine.

Adaptive query parallelization in multi-core column stores

NARCIS (Netherlands)

M.M. Gawade (Mrunal); M.L. Kersten (Martin); M.M. Gawade (Mrunal); M.L. Kersten (Martin)

2016-01-01

htmlabstractWith the rise of multi-core CPU platforms, their optimal utilization for in-memory OLAP workloads using column store databases has become one of the biggest challenges. Some of the inherent limi- tations in the achievable query parallelism are due to the degree of parallelism

Stochastic multi-period multi-product multi-objective Aggregate Production Planning model in multi-echelon supply chain

Directory of Open Access Journals (Sweden)

Kaveh Khalili-Damghani

2017-07-01

Full Text Available In this paper a multi-period multi-product multi-objective aggregate production planning (APP model is proposed for an uncertain multi-echelon supply chain considering financial risk, customer satisfaction, and human resource training. Three conflictive objective functions and several sets of real constraints are considered concurrently in the proposed APP model. Some parameters of the proposed model are assumed to be uncertain and handled through a two-stage stochastic programming (TSSP approach. The proposed TSSP is solved using three multi-objective solution procedures, i.e., the goal attainment technique, the modified ε-constraint method, and STEM method. The whole procedure is applied in an automotive resin and oil supply chain as a real case study wherein the efficacy and applicability of the proposed approaches are illustrated in comparison with existing experimental production planning method.

Fusion reactor handling operations with cable-driven parallel robots

Energy Technology Data Exchange (ETDEWEB)

Izard, Jean-Baptiste, E-mail: jeanbaptiste.izard@tecnalia.com; Michelin, Micael; Baradat, Cédric

2015-10-15

Highlights: • CDPR allow 6DOF positioning of loads using cable as links without payload swag. • Conceptual design of a CDPR for carrying and positioning tokamak sectors is given. • A CDPR for threading stellarator coils (6D trajectory following) is provided. • Both designs are capable of fullfilling the required precision without tooling. - Abstract: Cable-driven parallel robots (CDPR) are in their concept cranes with inclined cables which allow control of all the degrees of freedom of its payload, and therefore stability of all the degrees of freedom, including rotations. The workspace of a CDPR is only limited by the length of the cables, and the payload capacity related to the mass of the whole robot is very important. Besides, the control being based on kinematic models, the behavior of a CDPR is really that of a robot capable of automated trajectories or remote handling. The present paper gives a presentation of two use case studies based on some of the assembly phases and remote handling actions as designed for the recent fusion machines. Based on the use cases already in place in fusion reactor baselines, the opportunity of using CDPR for assembly of structural elements and coils is discussed. Finally, prospects for remote handling equipment from the reactor in hot cells are envisioned based on current CDPR research.

Optimum Design of Multi-Function Robot Arm Gripper for Varying Shape Green Product

Directory of Open Access Journals (Sweden)

Razali Zol Bahri

2016-01-01

Full Text Available The project focuses on thorough experimentally studies of the optimum design of Multi-function Robot Arm Gripper for varying shape green product. The purpose of this project is to design a few of robot arm gripper for multi-functionally grip a green product with varying shape. The main character of the gripper is that it can automated adjust its finger to suit with the shape of the product. An optimum design of multi-function robot arm gripper is verified through experimental study. The expected result is a series of analytical results on the proposal of gripper design and material that will be selected for the gripper. The analysis of the gripper design proposal by using ANSYS and CATIA software is described in detail in this paper.

Multi-sensors multi-baseline mapping system for mobile robot using stereovision camera and laser-range device

Directory of Open Access Journals (Sweden)

Mohammed Faisal

2016-06-01

Full Text Available Countless applications today are using mobile robots, including autonomous navigation, security patrolling, housework, search-and-rescue operations, material handling, manufacturing, and automated transportation systems. Regardless of the application, a mobile robot must use a robust autonomous navigation system. Autonomous navigation remains one of the primary challenges in the mobile-robot industry; many control algorithms and techniques have been recently developed that aim to overcome this challenge. Among autonomous navigation methods, vision-based systems have been growing in recent years due to rapid gains in computational power and the reliability of visual sensors. The primary focus of research into vision-based navigation is to allow a mobile robot to navigate in an unstructured environment without collision. In recent years, several researchers have looked at methods for setting up autonomous mobile robots for navigational tasks. Among these methods, stereovision-based navigation is a promising approach for reliable and efficient navigation. In this article, we create and develop a novel mapping system for a robust autonomous navigation system. The main contribution of this article is the fuse of the multi-baseline stereovision (narrow and wide baselines and laser-range reading data to enhance the accuracy of the point cloud, to reduce the ambiguity of correspondence matching, and to extend the field of view of the proposed mapping system to 180°. Another contribution is the pruning the region of interest of the three-dimensional point clouds to reduce the computational burden involved in the stereo process. Therefore, we called the proposed system multi-sensors multi-baseline mapping system. The experimental results illustrate the robustness and accuracy of the proposed system.

Control system of the inspection robots group applying auctions and multi-criteria analysis for task allocation

Science.gov (United States)

Panfil, Wawrzyniec; Moczulski, Wojciech

2017-10-01

In the paper presented is a control system of a mobile robots group intended for carrying out inspection missions. The main research problem was to define such a control system in order to facilitate a cooperation of the robots resulting in realization of the committed inspection tasks. Many of the well-known control systems use auctions for tasks allocation, where a subject of an auction is a task to be allocated. It seems that in the case of missions characterized by much larger number of tasks than number of robots it will be better if robots (instead of tasks) are subjects of auctions. The second identified problem concerns the one-sided robot-to-task fitness evaluation. Simultaneous assessment of the robot-to-task fitness and task attractiveness for robot should affect positively for the overall effectiveness of the multi-robot system performance. The elaborated system allows to assign tasks to robots using various methods for evaluation of fitness between robots and tasks, and using some tasks allocation methods. There is proposed the method for multi-criteria analysis, which is composed of two assessments, i.e. robot's concurrency position for task among other robots and task's attractiveness for robot among other tasks. Furthermore, there are proposed methods for tasks allocation applying the mentioned multi-criteria analysis method. The verification of both the elaborated system and the proposed tasks' allocation methods was carried out with the help of simulated experiments. The object under test was a group of inspection mobile robots being a virtual counterpart of the real mobile-robot group.

Interacting with Multi-Robot Systems Using BML

Science.gov (United States)

2013-06-01

presented to the operator. 1. Introduction There are many operations in which a multi-robot system (MRS) can be deployed to support the human forces...within the MRS easily. © Fraunhofer FKIE Communication Architecture ~ ~ Fraunhofer FKIE © Fraunhofer FKIE Battle Mangement Language BML...Fraunhofer FKIE Battle Mangement Language Orders Orders move patrol observe distribute guard recce imagery intelligence gathering

Muecas: A Multi-Sensor Robotic Head for Affective Human Robot Interaction and Imitation

Directory of Open Access Journals (Sweden)

Felipe Cid

2014-04-01

Full Text Available This paper presents a multi-sensor humanoid robotic head for human robot interaction. The design of the robotic head, Muecas, is based on ongoing research on the mechanisms of perception and imitation of human expressions and emotions. These mechanisms allow direct interaction between the robot and its human companion through the different natural language modalities: speech, body language and facial expressions. The robotic head has 12 degrees of freedom, in a human-like configuration, including eyes, eyebrows, mouth and neck, and has been designed and built entirely by IADeX (Engineering, Automation and Design of Extremadura and RoboLab. A detailed description of its kinematics is provided along with the design of the most complex controllers. Muecas can be directly controlled by FACS (Facial Action Coding System, the de facto standard for facial expression recognition and synthesis. This feature facilitates its use by third party platforms and encourages the development of imitation and of goal-based systems. Imitation systems learn from the user, while goal-based ones use planning techniques to drive the user towards a final desired state. To show the flexibility and reliability of the robotic head, the paper presents a software architecture that is able to detect, recognize, classify and generate facial expressions in real time using FACS. This system has been implemented using the robotics framework, RoboComp, which provides hardware-independent access to the sensors in the head. Finally, the paper presents experimental results showing the real-time functioning of the whole system, including recognition and imitation of human facial expressions.

Low-communication parallel quantum multi-target preimage search

NARCIS (Netherlands)

Banegas, G.S.; Bernstein, D.J.; Adams, Carlisle; Camenisch, Jan

2017-01-01

The most important pre-quantum threat to AES-128 is the 1994 van Oorschot–Wiener “parallel rho method”, a low-communication parallel pre-quantum multi-target preimage-search algorithm. This algorithm uses a mesh of p small processors, each running for approximately 2 128 /pt 2128/pt fast steps, to

A Parallel Solver for Large-Scale Markov Chains

Czech Academy of Sciences Publication Activity Database

Benzi, M.; Tůma, Miroslav

2002-01-01

Roč. 41, - (2002), s. 135-153 ISSN 0168-9274 R&D Projects: GA AV ČR IAA2030801; GA ČR GA101/00/1035 Keywords : parallel preconditioning * iterative methods * discrete Markov chains * generalized inverses * singular matrices * graph partitioning * AINV * Bi-CGSTAB Subject RIV: BA - General Mathematics Impact factor: 0.504, year: 2002

Multi-robot task allocation based on two dimensional artificial fish swarm algorithm

Science.gov (United States)

Zheng, Taixiong; Li, Xueqin; Yang, Liangyi

2007-12-01

The problem of task allocation for multiple robots is to allocate more relative-tasks to less relative-robots so as to minimize the processing time of these tasks. In order to get optimal multi-robot task allocation scheme, a twodimensional artificial swarm algorithm based approach is proposed in this paper. In this approach, the normal artificial fish is extended to be two dimension artificial fish. In the two dimension artificial fish, each vector of primary artificial fish is extended to be an m-dimensional vector. Thus, each vector can express a group of tasks. By redefining the distance between artificial fish and the center of artificial fish, the behavior of two dimension fish is designed and the task allocation algorithm based on two dimension artificial swarm algorithm is put forward. At last, the proposed algorithm is applied to the problem of multi-robot task allocation and comparer with GA and SA based algorithm is done. Simulation and compare result shows the proposed algorithm is effective.

Using Multi-Robot Systems for Engineering Education: Teaching and Outreach with Large Numbers of an Advanced, Low-Cost Robot

Science.gov (United States)

McLurkin, J.; Rykowski, J.; John, M.; Kaseman, Q.; Lynch, A. J.

2013-01-01

This paper describes the experiences of using an advanced, low-cost robot in science, technology, engineering, and mathematics (STEM) education. It presents three innovations: It is a powerful, cheap, robust, and small advanced personal robot; it forms the foundation of a problem-based learning curriculum; and it enables a novel multi-robot…

Optimal Orientation Planning and Control Deviation Estimation on FAST Cable-Driven Parallel Robot

Directory of Open Access Journals (Sweden)

Hui Li

2014-03-01

Full Text Available The paper is devoted theoretically to the optimal orientation planning and control deviation estimation of FAST cable-driven parallel robot. Regarding the robot characteristics, the solutions are obtained from two constrained optimizations, both of which are based on the equilibrium of the cabin and the attention on force allocation among 6 cable tensions. A kind of control algorithm is proposed based on the position and force feedbacks. The analysis proves that the orientation control depends on force feedback and the optimal tension solution corresponding to the planned orientation. Finally, the estimation of orientation deviation is given under the limit range of tension errors.

Distributed Circumnavigation Control with Dynamic Spacings for a Heterogeneous Multi-robot System

OpenAIRE

Yao, Weijia; Luo, Sha; Lu, Huimin; Xiao, Junhao

2018-01-01

Circumnavigation control is useful in real-world applications such as entrapping a hostile target. In this paper, we consider a heterogeneous multi-robot system where robots have different physical properties, such as maximum movement speeds. Instead of equal-spacings, dynamic spacings according to robots' properties, which are termed utilities in this paper, will be more desirable in a scenario such as target entrapment. A distributed circumnavigation control algorithm based on utilities is ...

Multi-robot motion control for cooperative observation

Energy Technology Data Exchange (ETDEWEB)

Parker, L.E. [Oak Ridge National Lab., TN (United States). Center for Engineering Systems Advanced Research

1997-06-01

An important issue that arises in the automation of many security, surveillance, and reconnaissance tasks is that of monitoring (or observing) the movements of targets navigating in a bounded area of interest. A key research issue in these problems is that of sensor placement--determining where sensors should be located to maintain the targets in view. In complex applications involving limited-range sensors, the use of multiple sensors dynamically moving over time is required. In this paper, the authors investigate the use of a cooperative team of autonomous sensor-based robots for the observation of multiple moving targets. They focus primarily on developing the distributed control strategies that allow the robot team to attempt to minimize the total time in which targets escape observation by some robot team member in the area of interest. This paper first formalizes the problem and discusses related work. The authors then present a distributed approximate approach to solving this problem that combines low-level multi-robot control with higher-level reasoning control based on the ALLIANCE formalism. They analyze the effectiveness of the approach by comparing it to 3 other feasible algorithms for cooperative control, showing the superiority of the approach for a large class of problems.

Multi-robot motion control for cooperative observation

International Nuclear Information System (INIS)

Parker, L.E.

1997-01-01

An important issue that arises in the automation of many security, surveillance, and reconnaissance tasks is that of monitoring (or observing) the movements of targets navigating in a bounded area of interest. A key research issue in these problems is that of sensor placement--determining where sensors should be located to maintain the targets in view. In complex applications involving limited-range sensors, the use of multiple sensors dynamically moving over time is required. In this paper, the authors investigate the use of a cooperative team of autonomous sensor-based robots for the observation of multiple moving targets. They focus primarily on developing the distributed control strategies that allow the robot team to attempt to minimize the total time in which targets escape observation by some robot team member in the area of interest. This paper first formalizes the problem and discusses related work. The authors then present a distributed approximate approach to solving this problem that combines low-level multi-robot control with higher-level reasoning control based on the ALLIANCE formalism. They analyze the effectiveness of the approach by comparing it to 3 other feasible algorithms for cooperative control, showing the superiority of the approach for a large class of problems

Motion and operation planning of robotic systems background and practical approaches

CERN Document Server

Gomez-Barvo, Fernando

2015-01-01

This book addresses the broad multi-disciplinary topic of robotics, and presents the basic techniques for motion and operation planning in robotics systems. Gathering contributions from experts in diverse and wide ranging fields, it offers an overview of the most recent and cutting-edge practical applications of these methodologies. It covers both theoretical and practical approaches, and elucidates the transition from theory to implementation. An extensive analysis is provided, including humanoids, manipulators, aerial robots and ground mobile robots. ‘Motion and Operation Planning of Robotic Systems’ addresses the following topics: *The theoretical background of robotics. *Application of motion planning techniques to manipulators, such as serial and parallel manipulators. *Mobile robots planning, including robotic applications related to aerial robots, large scale robots and traditional wheeled robots. *Motion planning for humanoid robots. An invaluable reference text for graduate students and researche...

Integrable multi parametric SU(N) chain

International Nuclear Information System (INIS)

Foerster, Angela; Roditi, Itzhak; Rodrigues, Ligia M.C.S.

1996-03-01

We analyse integrable models associated to a multi parametric SU(N) R-matrix. We show that the Hamiltonians describe SU(N) chains with twisted boundary conditions and that the underlying algebraic structure is the multi parametric deformation of SU(N) enlarged by the introduction of a central element. (author). 15 refs

Motion control of planar parallel robot using the fuzzy descriptor system approach.

Science.gov (United States)

Vermeiren, Laurent; Dequidt, Antoine; Afroun, Mohamed; Guerra, Thierry-Marie

2012-09-01

This work presents the control of a two-degree of freedom parallel robot manipulator. A quasi-LPV approach, through the so-called TS fuzzy model and LMI constraints problems is used. Moreover, in this context a way to derive interesting control laws is to keep the descriptor form of the mechanical system. Therefore, new LMI problems have to be defined that helps to reduce the conservatism of the usual results. Some relaxations are also proposed to leave the pure quadratic stability/stabilization framework. A comparison study between the classical control strategies from robotics and the control design using TS fuzzy descriptor models is carried out to show the interest of the proposed approach. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

FRAMEWORK FOR AD HOC NETWORK COMMUNICATION IN MULTI-ROBOT SYSTEMS

Directory of Open Access Journals (Sweden)

Khilda Slyusar

2016-11-01

Full Text Available Assume a team of mobile robots operating in environments where no communication infrastructure like routers or access points is available. The robots have to create a mobile ad hoc network, in that case, it provides communication on peer-to-peer basis. The paper gives an overview of existing solutions how to route messages in such ad hoc networks between robots that are not directly connected and introduces a design of a software framework for realization of such communication. Feasibility of the proposed framework is shown on the example of distributed multi-robot exploration of an a priori unknown environment. Testing of developed functionality in an exploration scenario is based on results of several experiments with various input conditions of the exploration process and various sizes of a team and is described herein.

Multi-Robot Interfaces and Operator Situational Awareness: Study of the Impact of Immersion and Prediction.

Science.gov (United States)

Roldán, Juan Jesús; Peña-Tapia, Elena; Martín-Barrio, Andrés; Olivares-Méndez, Miguel A; Del Cerro, Jaime; Barrientos, Antonio

2017-07-27

Multi-robot missions are a challenge for operators in terms of workload and situational awareness. These operators have to receive data from the robots, extract information, understand the situation properly, make decisions, generate the adequate commands, and send them to the robots. The consequences of excessive workload and lack of awareness can vary from inefficiencies to accidents. This work focuses on the study of future operator interfaces of multi-robot systems, taking into account relevant issues such as multimodal interactions, immersive devices, predictive capabilities and adaptive displays. Specifically, four interfaces have been designed and developed: a conventional, a predictive conventional, a virtual reality and a predictive virtual reality interface. The four interfaces have been validated by the performance of twenty-four operators that supervised eight multi-robot missions of fire surveillance and extinguishing. The results of the workload and situational awareness tests show that virtual reality improves the situational awareness without increasing the workload of operators, whereas the effects of predictive components are not significant and depend on their implementation.

Multi-Robot Interfaces and Operator Situational Awareness: Study of the Impact of Immersion and Prediction

Science.gov (United States)

Peña-Tapia, Elena; Martín-Barrio, Andrés; Olivares-Méndez, Miguel A.

2017-01-01

Multi-robot missions are a challenge for operators in terms of workload and situational awareness. These operators have to receive data from the robots, extract information, understand the situation properly, make decisions, generate the adequate commands, and send them to the robots. The consequences of excessive workload and lack of awareness can vary from inefficiencies to accidents. This work focuses on the study of future operator interfaces of multi-robot systems, taking into account relevant issues such as multimodal interactions, immersive devices, predictive capabilities and adaptive displays. Specifically, four interfaces have been designed and developed: a conventional, a predictive conventional, a virtual reality and a predictive virtual reality interface. The four interfaces have been validated by the performance of twenty-four operators that supervised eight multi-robot missions of fire surveillance and extinguishing. The results of the workload and situational awareness tests show that virtual reality improves the situational awareness without increasing the workload of operators, whereas the effects of predictive components are not significant and depend on their implementation. PMID:28749407

Multi-Robot Interfaces and Operator Situational Awareness: Study of the Impact of Immersion and Prediction

Directory of Open Access Journals (Sweden)

Juan Jesús Roldán

2017-07-01

Full Text Available Multi-robot missions are a challenge for operators in terms of workload and situational awareness. These operators have to receive data from the robots, extract information, understand the situation properly, make decisions, generate the adequate commands, and send them to the robots. The consequences of excessive workload and lack of awareness can vary from inefficiencies to accidents. This work focuses on the study of future operator interfaces of multi-robot systems, taking into account relevant issues such as multimodal interactions, immersive devices, predictive capabilities and adaptive displays. Specifically, four interfaces have been designed and developed: a conventional, a predictive conventional, a virtual reality and a predictive virtual reality interface. The four interfaces have been validated by the performance of twenty-four operators that supervised eight multi-robot missions of fire surveillance and extinguishing. The results of the workload and situational awareness tests show that virtual reality improves the situational awareness without increasing the workload of operators, whereas the effects of predictive components are not significant and depend on their implementation.

A Robotic Coach Architecture for Elder Care (ROCARE) Based on Multi-User Engagement Models.

Science.gov (United States)

Fan, Jing; Bian, Dayi; Zheng, Zhi; Beuscher, Linda; Newhouse, Paul A; Mion, Lorraine C; Sarkar, Nilanjan

2017-08-01

The aging population with its concomitant medical conditions, physical and cognitive impairments, at a time of strained resources, establishes the urgent need to explore advanced technologies that may enhance function and quality of life. Recently, robotic technology, especially socially assistive robotics has been investigated to address the physical, cognitive, and social needs of older adults. Most system to date have predominantly focused on one-on-one human robot interaction (HRI). In this paper, we present a multi-user engagement-based robotic coach system architecture (ROCARE). ROCARE is capable of administering both one-on-one and multi-user HRI, providing implicit and explicit channels of communication, and individualized activity management for long-term engagement. Two preliminary feasibility studies, a one-on-one interaction and a triadic interaction with two humans and a robot, were conducted and the results indicated potential usefulness and acceptance by older adults, with and without cognitive impairment.

Modelling and Control of the Multi-Stage Cable Pulley-Driven Flexible-Joint Robot

Directory of Open Access Journals (Sweden)

Phongsaen Pitakwatchara

2014-07-01

Full Text Available This work is concerned with the task space impedance control of a robot driven through a multi-stage nonlinear flexible transmission system. Specifically, a two degrees-of-freedom cable pulley-driven flexible-joint robot is considered. Realistic modelling of the system is developed within the bond graph modelling framework. The model captures the nonlinear compliance behaviour of the multi-stage cable pulley transmission system, the spring effect of the augmented counterbalancing mechanism, the major loss throughout the system elements, and the typical inertial dynamics of the robot. Next, a task space impedance controller based on limited information about the angle and the current of the motors is designed. The motor current is used to infer the transmitted torque, by which the motor inertia may be modulated. The motor angle is employed to estimate the stationary distal robot link angle and the robot joint velocity. They are used in the controller to generate the desired damping force and to shape the potential energy of the flexible joint robot system to the desired configuration. Simulation and experimental results of the controlled system signify the competency of the proposed control law.

Novel Robot Solutions for Carrying out Field Joint Welding and Machining in the Assembly of the Vacuum Vessel of ITER

International Nuclear Information System (INIS)

Pessi, P.

2009-01-01

It is necessary to use highly specialized robots in ITER (International Thermonuclear Experimental Reactor) both in the manufacturing and maintenance of the reactor due to a demanding environment. The sectors of the ITER vacuum vessel (VV) require more stringent tolerances than normally expected for the size of the structure involved. VV consists of nine sectors that are to be welded together. The vacuum vessel has a toroidal chamber structure. The task of the designed robot is to carry the welding apparatus along a path with a stringent tolerance during the assembly operation. In addition to the initial vacuum vessel assembly, after a limited running period, sectors need to be replaced for repair. Mechanisms with closed-loop kinematic chains are used in the design of robots in this work. One version is a purely parallel manipulator and another is a hybrid manipulator where the parallel and serial structures are combined. Traditional industrial robots that generally have the links actuated in series are inherently not very rigid and have poor dynamic performance in high speed and high dynamic loading conditions. Compared with open chain manipulators, parallel manipulators have high stiffness, high accuracy and a high force/torque capacity in a reduced workspace. Parallel manipulators have a mechanical architecture where all of the links are connected to the base and to the end-effector of the robot. The purpose of this thesis is to develop special parallel robots for the assembly, machining and repairing of the VV of the ITER. The process of the assembly and machining of the vacuum vessel needs a special robot. By studying the structure of the vacuum vessel, two novel parallel robots were designed and built; they have six and ten degrees of freedom driven by hydraulic cylinders and electrical servo motors. Kinematic models for the proposed robots were defined and two prototypes built. Experiments for machine cutting and laser welding with the 6-DOF robot were

Novel Robot Solutions for Carrying out Field Joint Welding and Machining in the Assembly of the Vacuum Vessel of ITER

Energy Technology Data Exchange (ETDEWEB)

Pessi, P.

2009-07-01

It is necessary to use highly specialized robots in ITER (International Thermonuclear Experimental Reactor) both in the manufacturing and maintenance of the reactor due to a demanding environment. The sectors of the ITER vacuum vessel (VV) require more stringent tolerances than normally expected for the size of the structure involved. VV consists of nine sectors that are to be welded together. The vacuum vessel has a toroidal chamber structure. The task of the designed robot is to carry the welding apparatus along a path with a stringent tolerance during the assembly operation. In addition to the initial vacuum vessel assembly, after a limited running period, sectors need to be replaced for repair. Mechanisms with closed-loop kinematic chains are used in the design of robots in this work. One version is a purely parallel manipulator and another is a hybrid manipulator where the parallel and serial structures are combined. Traditional industrial robots that generally have the links actuated in series are inherently not very rigid and have poor dynamic performance in high speed and high dynamic loading conditions. Compared with open chain manipulators, parallel manipulators have high stiffness, high accuracy and a high force/torque capacity in a reduced workspace. Parallel manipulators have a mechanical architecture where all of the links are connected to the base and to the end-effector of the robot. The purpose of this thesis is to develop special parallel robots for the assembly, machining and repairing of the VV of the ITER. The process of the assembly and machining of the vacuum vessel needs a special robot. By studying the structure of the vacuum vessel, two novel parallel robots were designed and built; they have six and ten degrees of freedom driven by hydraulic cylinders and electrical servo motors. Kinematic models for the proposed robots were defined and two prototypes built. Experiments for machine cutting and laser welding with the 6-DOF robot were

Design Analysis and Dynamic Modeling of a High-Speed 3T1R Pick-and-Place Parallel Robot

DEFF Research Database (Denmark)

Wu, Guanglei; Bai, Shaoping; Hjørnet, Preben

2015-01-01

This paper introduces a four degree-of-freedom parallel robot producing three translation and one rotation (Schönflies motion). This robot can generate a rectangular workspace that is close to the applicable work envelope and suitable for pick-and-place operations. The kinematics of the robot...... is studied to analyze the workspace and the isocontours of the local dexterity over the representative regular workspace are visualized. The simplified dynamics is modeled and compared with Adams model to show its effectiveness....

L-ALLIANCE: a mechanism for adaptive action selection in heterogeneous multi-robot teams

Energy Technology Data Exchange (ETDEWEB)

Parker, L.E.

1995-11-01

In practical applications of robotics, it is usually quite difficult, if not impossible, for the system designer to fully predict the environmental states in which the robots will operate. The complexity of the problem is further increased when dealing with teams of robots which themselves may be incompletely known and characterized in advance. It is thus highly desirable for robot teams to be able to adapt their performance during the mission due to changes in the environment, or to changes in other robot team members. In previous work, we introduced a behavior-based mechanism called the ALLIANCE architecture -- that facilitates the fault tolerant cooperative control of multi-robot teams. However, this previous work did not address the issue of how to dynamically update the control parameters during a mission to adapt to ongoing changes in the environment or in the robot team, and to ensure the efficiency of the collective team actions. In this paper, we address this issue by proposing the L-ALLIANCE mechanism, which defines an automated method whereby robots can use knowledge learned from previous experience to continually improve their collective action selection when working on missions composed of loosely coupled, discrete subtasks. This ability to dynamically update robotic control parameters provides a number of distinct advantages: it alleviates the need for human tuning of control parameters, it facilitates the use of custom-designed multi-robot teams for any given application, it improves the efficiency of the mission performance, and It allows robots to continually adapt their performance over time due to changes in the robot team and/or the environment. We describe the L-ALLIANCE mechanism, present the results of various alternative update strategies we investigated, present the formal model of the L-ALLIANCE mechanism, and present the results of a simple proof of concept implementation on a small team of heterogeneous mobile robots.

Parallel Computational Intelligence-Based Multi-Camera Surveillance System

Directory of Open Access Journals (Sweden)

Sergio Orts-Escolano

2014-04-01

Full Text Available In this work, we present a multi-camera surveillance system based on the use of self-organizing neural networks to represent events on video. The system processes several tasks in parallel using GPUs (graphic processor units. It addresses multiple vision tasks at various levels, such as segmentation, representation or characterization, analysis and monitoring of the movement. These features allow the construction of a robust representation of the environment and interpret the behavior of mobile agents in the scene. It is also necessary to integrate the vision module into a global system that operates in a complex environment by receiving images from multiple acquisition devices at video frequency. Offering relevant information to higher level systems, monitoring and making decisions in real time, it must accomplish a set of requirements, such as: time constraints, high availability, robustness, high processing speed and re-configurability. We have built a system able to represent and analyze the motion in video acquired by a multi-camera network and to process multi-source data in parallel on a multi-GPU architecture.

Medical Image Retrieval Based On the Parallelization of the Cluster Sampling Algorithm

OpenAIRE

Ali, Hesham Arafat; Attiya, Salah; El-henawy, Ibrahim

2017-01-01

In this paper we develop parallel cluster sampling algorithms and show that a multi-chain version is embarrassingly parallel and can be used efficiently for medical image retrieval among other applications.

Development and human factors analysis of an augmented reality interface for multi-robot tele-operation and control

Science.gov (United States)

Lee, Sam; Lucas, Nathan P.; Ellis, R. Darin; Pandya, Abhilash

2012-06-01

This paper presents a seamlessly controlled human multi-robot system comprised of ground and aerial robots of semiautonomous nature for source localization tasks. The system combines augmented reality interfaces capabilities with human supervisor's ability to control multiple robots. The role of this human multi-robot interface is to allow an operator to control groups of heterogeneous robots in real time in a collaborative manner. It used advanced path planning algorithms to ensure obstacles are avoided and that the operators are free for higher-level tasks. Each robot knows the environment and obstacles and can automatically generate a collision-free path to any user-selected target. It displayed sensor information from each individual robot directly on the robot in the video view. In addition, a sensor data fused AR view is displayed which helped the users pin point source information or help the operator with the goals of the mission. The paper studies a preliminary Human Factors evaluation of this system in which several interface conditions are tested for source detection tasks. Results show that the novel Augmented Reality multi-robot control (Point-and-Go and Path Planning) reduced mission completion times compared to the traditional joystick control for target detection missions. Usability tests and operator workload analysis are also investigated.

Structure Assembly by a Heterogeneous Team of Robots Using State Estimation, Generalized Joints, and Mobile Parallel Manipulators

Science.gov (United States)

Komendera, Erik E.; Adhikari, Shaurav; Glassner, Samantha; Kishen, Ashwin; Quartaro, Amy

2017-01-01

Autonomous robotic assembly by mobile field robots has seen significant advances in recent decades, yet practicality remains elusive. Identified challenges include better use of state estimation to and reasoning with uncertainty, spreading out tasks to specialized robots, and implementing representative joining methods. This paper proposes replacing 1) self-correcting mechanical linkages with generalized joints for improved applicability, 2) assembly serial manipulators with parallel manipulators for higher precision and stability, and 3) all-in-one robots with a heterogeneous team of specialized robots for agent simplicity. This paper then describes a general assembly algorithm utilizing state estimation. Finally, these concepts are tested in the context of solar array assembly, requiring a team of robots to assemble, bond, and deploy a set of solar panel mockups to a backbone truss to an accuracy not built into the parts. This paper presents the results of these tests.

A concept of distributed architecture for maintenance robot systems

International Nuclear Information System (INIS)

Asama, Hajime

1990-01-01

Aiming at development of a robot system for maintenance tasks in nuclear power plants, a concept of distributed architecture for autonomous robot systems is discussed. At first, based on investigation of maintenance tasks, requirements for maintenance robots are introduced, and structures to realize multi-functions are discussed. Then, as a new design strategy of maintenance robot system, an autonomous and decentralized robot systems is proposed, which is composed of multiple robots, computers, and equipments, and concept of ACTRESS (ACTor-based Robots and Equipments Synthetic System) including communication framework between robotic components is designed. Finally, as a model of ACTRESS, a experimental system is developed, which deals with object-pushing tasks by two micromice and an environment modeler with communicating with each other. Both of parallel independent motion and cooperative motion based on communication is reconciled, and the efficiency of the distributed architecture is verified. (author)

On the effective parallel programming of multi-core processors

NARCIS (Netherlands)

Varbanescu, A.L.

2010-01-01

Multi-core processors are considered now the only feasible alternative to the large single-core processors which have become limited by technological aspects such as power consumption and heat dissipation. However, due to their inherent parallel structure and their diversity, multi-cores are

Automatic approach to stabilization and control for multi robot teams by multilayer network operator

Directory of Open Access Journals (Sweden)

Diveev Askhat

2016-01-01

Full Text Available The paper describes a novel methodology for synthesis a high-level control of autonomous multi robot teams. The approach is based on multilayer network operator method that belongs to a symbolic regression class. Synthesis is accomplished in three steps: stabilizing robots about some given position in a state space, finding optimal trajectories of robots’ motion as sets of stabilizing points and then approximating all the points of optimal trajectories by some multi-dimensional function of state variables. The feasibility and effectiveness of the proposed approach is verified on simulations of the task of control synthesis for three mobile robots parking in the constrained space.

Multi-sensor integration for autonomous robots in nuclear power plants

International Nuclear Information System (INIS)

Mann, R.C.; Jones, J.P.; Beckerman, M.; Glover, C.W.; Farkas, L.; Bilbro, G.L.; Snyder, W.

1989-01-01

As part of a concerted RandD program in advanced robotics for hazardous environments, scientists and engineers at the Oak Ridge National Laboratory (ORNL) are performing research in the areas of systems integration, range-sensor-based 3-D world modeling, and multi-sensor integration. This program features a unique teaming arrangement that involves the universities of Florida, Michigan, Tennessee, and Texas; Odetics Corporation; and ORNL. This paper summarizes work directed at integrating information extracted from data collected with range sensors and CCD cameras on-board a mobile robot, in order to produce reliable descriptions of the robot's environment. Specifically, the paper describes the integration of two-dimensional vision and sonar range information, and an approach to integrate registered luminance and laser range images. All operations are carried out on-board the mobile robot using a 16-processor hypercube computer. 14 refs., 4 figs

Multi-core parallelism in a column-store

NARCIS (Netherlands)

Gawade, M.M.

2017-01-01

The research reported in this thesis addresses several challenges of improving the efficiency and effectiveness of parallel processing of analytical database queries on modern multi- and many-core systems, using an open-source column-oriented analytical database management system, MonetDB, for

A Framework for Multi-Robot Motion Planning from Temporal Logic Specifications

DEFF Research Database (Denmark)

Koo, T. John; Li, Rongqing; Quottrup, Michael Melholt

2012-01-01

-time Temporal Logic, Computation Tree Logic, and -calculus can be preserved. Motion planning can then be performed at a discrete level by considering the parallel composition of discrete abstractions of the robots with a requirement specification given in a suitable temporal logic. The bisimilarity ensures...

Robust Visual Control of Parallel Robots under Uncertain Camera Orientation

Directory of Open Access Journals (Sweden)

Miguel A. Trujano

2012-10-01

Full Text Available This work presents a stability analysis and experimental assessment of a visual control algorithm applied to a redundant planar parallel robot under uncertainty in relation to camera orientation. The key feature of the analysis is a strict Lyapunov function that allows the conclusion of asymptotic stability without invoking the Barbashin-Krassovsky-LaSalle invariance theorem. The controller does not rely on velocity measurements and has a structure similar to a classic Proportional Derivative control algorithm. Experiments in a laboratory prototype show that uncertainty in camera orientation does not significantly degrade closed-loop performance.

Multi-Axis Force Sensor for Human-Robot Interaction Sensing in a Rehabilitation Robotic Device.

Science.gov (United States)

Grosu, Victor; Grosu, Svetlana; Vanderborght, Bram; Lefeber, Dirk; Rodriguez-Guerrero, Carlos

2017-06-05

Human-robot interaction sensing is a compulsory feature in modern robotic systems where direct contact or close collaboration is desired. Rehabilitation and assistive robotics are fields where interaction forces are required for both safety and increased control performance of the device with a more comfortable experience for the user. In order to provide an efficient interaction feedback between the user and rehabilitation device, high performance sensing units are demanded. This work introduces a novel design of a multi-axis force sensor dedicated for measuring pelvis interaction forces in a rehabilitation exoskeleton device. The sensor is conceived such that it has different sensitivity characteristics for the three axes of interest having also movable parts in order to allow free rotations and limit crosstalk errors. Integrated sensor electronics make it easy to acquire and process data for a real-time distributed system architecture. Two of the developed sensors are integrated and tested in a complex gait rehabilitation device for safe and compliant control.

Development of a Stereo Vision Measurement System for a 3D Three-Axial Pneumatic Parallel Mechanism Robot Arm

Directory of Open Access Journals (Sweden)

Chien-Lun Hou

2011-02-01

Full Text Available In this paper, a stereo vision 3D position measurement system for a three-axial pneumatic parallel mechanism robot arm is presented. The stereo vision 3D position measurement system aims to measure the 3D trajectories of the end-effector of the robot arm. To track the end-effector of the robot arm, the circle detection algorithm is used to detect the desired target and the SAD algorithm is used to track the moving target and to search the corresponding target location along the conjugate epipolar line in the stereo pair. After camera calibration, both intrinsic and extrinsic parameters of the stereo rig can be obtained, so images can be rectified according to the camera parameters. Thus, through the epipolar rectification, the stereo matching process is reduced to a horizontal search along the conjugate epipolar line. Finally, 3D trajectories of the end-effector are computed by stereo triangulation. The experimental results show that the stereo vision 3D position measurement system proposed in this paper can successfully track and measure the fifth-order polynomial trajectory and sinusoidal trajectory of the end-effector of the three- axial pneumatic parallel mechanism robot arm.

Development and control towards a parallel water hydraulic weld/cut robot for machining processes in ITER vacuum vessel

International Nuclear Information System (INIS)

Wu Huapeng; Handroos, Heikki; Pessi, Pekka; Kilkki, Juha; Jones, Lawrence

2005-01-01

This paper presents a special robot, able to carry out welding and machining processes from inside the ITER vacuum vessel (VV), consisting of a five degree-of-freedom parallel mechanism, mounted on a carriage driven by two electric motors on a rack. The kinematic design of the robot has been optimised for ITER access and a hydraulically actuated pre-prototype built. A hybrid controller is designed for the robot, including position, speed and pressure feedback loops to achieve high accuracy and high dynamic performances. Finally, the experimental tests are given and discussed

Demand management in Multi-Stage Distribution Chain

NARCIS (Netherlands)

de Kok, T.; Janssen, F.B.S.L.P.

1996-01-01

In this paper we discuss demand management problems in a multi-stage distribution chain.We focus on distribution chains where demand processes have high variability due to a few large customer orders.We give a possible explanation, and suggest two simple procedures that help to smooth demand.It is

A language for data-parallel and task parallel programming dedicated to multi-SIMD computers. Contributions to hydrodynamic simulation with lattice gases

International Nuclear Information System (INIS)

Pic, Marc Michel

1995-01-01

Parallel programming covers task-parallelism and data-parallelism. Many problems need both parallelisms. Multi-SIMD computers allow hierarchical approach of these parallelisms. The T++ language, based on C++, is dedicated to exploit Multi-SIMD computers using a programming paradigm which is an extension of array-programming to tasks managing. Our language introduced array of independent tasks to achieve separately (MIMD), on subsets of processors of identical behaviour (SIMD), in order to translate the hierarchical inclusion of data-parallelism in task-parallelism. To manipulate in a symmetrical way tasks and data we propose meta-operations which have the same behaviour on tasks arrays and on data arrays. We explain how to implement this language on our parallel computer SYMPHONIE in order to profit by the locally-shared memory, by the hardware virtualization, and by the multiplicity of communications networks. We analyse simultaneously a typical application of such architecture. Finite elements scheme for Fluid mechanic needs powerful parallel computers and requires large floating points abilities. Lattice gases is an alternative to such simulations. Boolean lattice bases are simple, stable, modular, need to floating point computation, but include numerical noise. Boltzmann lattice gases present large precision of computation, but needs floating points and are only locally stable. We propose a new scheme, called multi-bit, who keeps the advantages of each boolean model to which it is applied, with large numerical precision and reduced noise. Experiments on viscosity, physical behaviour, noise reduction and spurious invariants are shown and implementation techniques for parallel Multi-SIMD computers detailed. (author) [fr

Towards Sociable Robots

DEFF Research Database (Denmark)

Ngo, Trung Dung

This thesis studies aspects of self-sufficient energy (energy autonomy) for truly autonomous robots and towards sociable robots. Over sixty years of history of robotics through three developmental ages containing single robot, multi-robot systems, and social (sociable) robots, the main objective...... of roboticists mostly focuses on how to make a robotic system function autonomously and further, socially. However, such approaches mostly emphasize behavioural autonomy, rather than energy autonomy which is the key factor for not only any living machine, but for life on the earth. Consequently, self......-sufficient energy is one of the challenges for not only single robot or multi-robot systems, but also social and sociable robots. This thesis is to deal with energy autonomy for multi-robot systems through energy sharing (trophallaxis) in which each robot is equipped with two capabilities: self-refueling energy...

Optimization of multi-phase compressible lattice Boltzmann codes on massively parallel multi-core systems

NARCIS (Netherlands)

Biferale, L.; Mantovani, F.; Pivanti, M.; Pozzati, F.; Sbragaglia, M.; Schifano, S.F.; Toschi, F.; Tripiccione, R.

2011-01-01

We develop a Lattice Boltzmann code for computational fluid-dynamics and optimize it for massively parallel systems based on multi-core processors. Our code describes 2D multi-phase compressible flows. We analyze the performance bottlenecks that we find as we gradually expose a larger fraction of

Experimental Study of Active Vibration Control of Planar 3-RRR Flexible Parallel Robots Mechanism

Directory of Open Access Journals (Sweden)

Qinghua Zhang

2016-01-01

Full Text Available An active vibration control experiment of planar 3-RRR flexible parallel robots is implemented in this paper. Considering the direct and inverse piezoelectric effect of PZT material, a general motion equation is established. A strain rate feedback controller is designed based on the established general motion equation. Four control schemes are designed in this experiment: three passive flexible links are controlled at the same time, only passive flexible link 1 is controlled, only passive flexible link 2 is controlled, and only passive flexible link 3 is controlled. The experimental results show that only one flexible link controlled scheme  suppresses elastic vibration and cannot suppress the elastic vibration of the other flexible links, whereas when three passive flexible links are controlled at the same time, they are able to effectively suppress the elastic vibration of all of the flexible links. In general, the experiment verifies that a strain rate feedback controller is able to effectively suppress the elastic vibration of the flexible links of plane 3-RRR flexible parallel robots.

Trajectory control of an articulated robot with a parallel drive arm based on splines under tension

Science.gov (United States)

Yi, Seung-Jong

Today's industrial robots controlled by mini/micro computers are basically simple positioning devices. The positioning accuracy depends on the mathematical description of the robot configuration to place the end-effector at the desired position and orientation within the workspace and on following the specified path which requires the trajectory planner. In addition, the consideration of joint velocity, acceleration, and jerk trajectories are essential for trajectory planning of industrial robots to obtain smooth operation. The newly designed 6 DOF articulated robot with a parallel drive arm mechanism which permits the joint actuators to be placed in the same horizontal line to reduce the arm inertia and to increase load capacity and stiffness is selected. First, the forward kinematic and inverse kinematic problems are examined. The forward kinematic equations are successfully derived based on Denavit-Hartenberg notation with independent joint angle constraints. The inverse kinematic problems are solved using the arm-wrist partitioned approach with independent joint angle constraints. Three types of curve fitting methods used in trajectory planning, i.e., certain degree polynomial functions, cubic spline functions, and cubic spline functions under tension, are compared to select the best possible method to satisfy both smooth joint trajectories and positioning accuracy for a robot trajectory planner. Cubic spline functions under tension is the method selected for the new trajectory planner. This method is implemented for a 6 DOF articulated robot with a parallel drive arm mechanism to improve the smoothness of the joint trajectories and the positioning accuracy of the manipulator. Also, this approach is compared with existing trajectory planners, 4-3-4 polynomials and cubic spline functions, via circular arc motion simulations. The new trajectory planner using cubic spline functions under tension is implemented into the microprocessor based robot controller and

Design and characterization of a multi-articulated robotic bat wing

International Nuclear Information System (INIS)

Bahlman, Joseph W; Swartz, Sharon M; Breuer, Kenneth S

2013-01-01

There are many challenges to measuring power input and force output from a flapping vertebrate. Animals can vary a multitude of kinematic parameters simultaneously, and methods for measuring power and force are either not possible in a flying vertebrate or are very time and equipment intensive. To circumvent these challenges, we constructed a robotic, multi-articulated bat wing that allows us to measure power input and force output simultaneously, across a range of kinematic parameters. The robot is modeled after the lesser dog-faced fruit bat, Cynopterus brachyotis, and contains seven joints powered by three servo motors. Collectively, this joint and motor arrangement allows the robot to vary wingbeat frequency, wingbeat amplitude, stroke plane, downstroke ratio, and wing folding. We describe the design, construction, programing, instrumentation, characterization, and analysis of the robot. We show that the kinematics, inputs, and outputs demonstrate good repeatability both within and among trials. Finally, we describe lessons about the structure of living bats learned from trying to mimic their flight in a robotic wing. (paper)

Multi-petascale highly efficient parallel supercomputer

Science.gov (United States)

Asaad, Sameh; Bellofatto, Ralph E.; Blocksome, Michael A.; Blumrich, Matthias A.; Boyle, Peter; Brunheroto, Jose R.; Chen, Dong; Cher, Chen-Yong; Chiu, George L.; Christ, Norman; Coteus, Paul W.; Davis, Kristan D.; Dozsa, Gabor J.; Eichenberger, Alexandre E.; Eisley, Noel A.; Ellavsky, Matthew R.; Evans, Kahn C.; Fleischer, Bruce M.; Fox, Thomas W.; Gara, Alan; Giampapa, Mark E.; Gooding, Thomas M.; Gschwind, Michael K.; Gunnels, John A.; Hall, Shawn A.; Haring, Rudolf A.; Heidelberger, Philip; Inglett, Todd A.; Knudson, Brant L.; Kopcsay, Gerard V.; Kumar, Sameer; Mamidala, Amith R.; Marcella, James A.; Megerian, Mark G.; Miller, Douglas R.; Miller, Samuel J.; Muff, Adam J.; Mundy, Michael B.; O'Brien, John K.; O'Brien, Kathryn M.; Ohmacht, Martin; Parker, Jeffrey J.; Poole, Ruth J.; Ratterman, Joseph D.; Salapura, Valentina; Satterfield, David L.; Senger, Robert M.; Steinmacher-Burow, Burkhard; Stockdell, William M.; Stunkel, Craig B.; Sugavanam, Krishnan; Sugawara, Yutaka; Takken, Todd E.; Trager, Barry M.; Van Oosten, James L.; Wait, Charles D.; Walkup, Robert E.; Watson, Alfred T.; Wisniewski, Robert W.; Wu, Peng

2018-05-15

A Multi-Petascale Highly Efficient Parallel Supercomputer of 100 petaflop-scale includes node architectures based upon System-On-a-Chip technology, where each processing node comprises a single Application Specific Integrated Circuit (ASIC). The ASIC nodes are interconnected by a five dimensional torus network that optimally maximize the throughput of packet communications between nodes and minimize latency. The network implements collective network and a global asynchronous network that provides global barrier and notification functions. Integrated in the node design include a list-based prefetcher. The memory system implements transaction memory, thread level speculation, and multiversioning cache that improves soft error rate at the same time and supports DMA functionality allowing for parallel processing message-passing.

Multi-chain Markov chain Monte Carlo methods for computationally expensive models

Science.gov (United States)

Huang, M.; Ray, J.; Ren, H.; Hou, Z.; Bao, J.

2017-12-01

Markov chain Monte Carlo (MCMC) methods are used to infer model parameters from observational data. The parameters are inferred as probability densities, thus capturing estimation error due to sparsity of the data, and the shortcomings of the model. Multiple communicating chains executing the MCMC method have the potential to explore the parameter space better, and conceivably accelerate the convergence to the final distribution. We present results from tests conducted with the multi-chain method to show how the acceleration occurs i.e., for loose convergence tolerances, the multiple chains do not make much of a difference. The ensemble of chains also seems to have the ability to accelerate the convergence of a few chains that might start from suboptimal starting points. Finally, we show the performance of the chains in the estimation of O(10) parameters using computationally expensive forward models such as the Community Land Model, where the sampling burden is distributed over multiple chains.

Brain-state dependent robotic reaching movement with a multi-joint arm exoskeleton: combining brain-machine interfacing and robotic rehabilitation

Directory of Open Access Journals (Sweden)

Daniel eBrauchle

2015-10-01

Full Text Available While robot-assisted arm and hand training after stroke allows for intensive task-oriented practice, it has provided only limited additional benefit over dose-matched physiotherapy up to now. These rehabilitation devices are possibly too supportive during the exercises. Neurophysiological signals might be one way of avoiding slacking and providing robotic support only when the brain is particularly responsive to peripheral input.We tested the feasibility of three-dimensional robotic assistance for reach-to-grasp movements with a multi-joint exoskeleton during motor imagery-related desynchronization of sensorimotor oscillations in the β-band only. We also registered task-related network changes of cortical functional connectivity by electroencephalography via the imaginary part of the coherence function.Healthy subjects and stroke survivors showed similar patterns – but different aptitudes – of controlling the robotic movement. All participants in this pilot study with nine healthy subjects and two stroke patients achieved their maximum performance during the early stages of the task. Robotic control was significantly higher and less variable when proprioceptive feedback was provided in addition to visual feedback, i.e. when the orthosis was actually attached to the subject’s arm during the task. A distributed cortical network of task-related coherent activity in the θ-band showed significant differences between healthy subjects and stroke patients as well as between early and late periods of the task.Brain-robot interfaces may successfully link three-dimensional robotic training to the participants’ efforts and allow for task-oriented practice of activities of daily living with a physiologically controlled multi-joint exoskeleton. Changes of cortical physiology during the task might also help to make subject-specific adjustments of task difficulty and guide adjunct interventions to facilitate motor learning for functional restoration.

Rendezvous with connectivity preservation for multi-robot systems with an unknown leader

Science.gov (United States)

Dong, Yi

2018-02-01

This paper studies the leader-following rendezvous problem with connectivity preservation for multi-agent systems composed of uncertain multi-robot systems subject to external disturbances and an unknown leader, both of which are generated by a so-called exosystem with parametric uncertainty. By combining internal model design, potential function technique and adaptive control, two distributed control strategies are proposed to maintain the connectivity of the communication network, to achieve the asymptotic tracking of all the followers to the output of the unknown leader system, as well as to reject unknown external disturbances. It is also worth to mention that the uncertain parameters in the multi-robot systems and exosystem are further allowed to belong to unknown and unbounded sets when applying the second fully distributed control law containing a dynamic gain inspired by high-gain adaptive control or self-tuning regulator.

Design and Programming for Cable-Driven Parallel Robots in the German Pavilion at the EXPO 2015

Directory of Open Access Journals (Sweden)

Philipp Tempel

2015-08-01

Full Text Available In the German Pavilion at the EXPO 2015, two large cable-driven parallel robots are flying over the heads of the visitors representing two bees flying over Germany and displaying everyday life in Germany. Each robot consists of a mobile platform and eight cables suspended by winches and follows a desired trajectory, which needs to be computed in advance taking technical limitations, safety considerations and visual aspects into account. In this paper, a path planning software is presented, which includes the design process from developing a robot design and workspace estimation via planning complex trajectories considering technical limitations through to exporting a complete show. For a test trajectory, simulation results are given, which display the relevant trajectories and cable force distributions.

The Control Based on Internal Average Kinetic Energy in Complex Environment for Multi-robot System

Science.gov (United States)

Yang, Mao; Tian, Yantao; Yin, Xianghua

In this paper, reference trajectory is designed according to minimum energy consumed for multi-robot system, which nonlinear programming and cubic spline interpolation are adopted. The control strategy is composed of two levels, which lower-level is simple PD control and the upper-level is based on the internal average kinetic energy for multi-robot system in the complex environment with velocity damping. Simulation tests verify the effectiveness of this control strategy.

Design and Analysis of a Bio-Inspired Wire-Driven Multi-Section Flexible Robot

OpenAIRE

Li, Zheng; Du, Ruxu

2013-01-01

This paper presents a bio-inspired wire-driven multi-section flexible robot. It is inspired by the snake skeleton and octopus arm muscle arrangements. The robot consists of three sections and each section is made up of several identical vertebras, which are articulated by both spherical joints and a flexible backbone. Each section is driven by two groups of wires, controlling the bending motion in X and Y directions. This design integrates the serpentine robots' structure and the continuum ro...

multiPDEVS: A Parallel Multicomponent System Specification Formalism

Directory of Open Access Journals (Sweden)

Damien Foures

2018-01-01

Full Text Available Based on multiDEVS formalism, we introduce multiPDEVS, a parallel and nonmodular formalism for discrete event system specification. This formalism provides combined advantages of PDEVS and multiDEVS approaches, such as excellent simulation capabilities for simultaneously scheduled events and components able to influence each other using exclusively their state transitions. We next show the soundness of the formalism by giving a construction showing that any multiPDEVS model is equivalent to a PDEVS atomic model. We then present the simulation procedure associated, usually called abstract simulator. As a well-adapted formalism to express cellular automata, we finally propose to compare an implementation of multiPDEVS formalism with a more classical Cell-DEVS implementation through a fire spread application.

TRUST MODEL FOR INFORMATION SECURITY OF MULTI-AGENT ROBOTIC SYSTEMS WITH A DECENTRALIZED MANAGEMENT

Directory of Open Access Journals (Sweden)

I. A. Zikratov

2014-03-01

Full Text Available The paper deals with the issues on protection of multi-agent robotic systems against attacks by robots-saboteurs. The operation analysis of such systems with decentralized control is carried out. Concept of harmful information impact (attack from a robot-saboteur to the multi-agent robotic system is given. The class of attacks is considered using interception of messages, formation and transfer of misinformation to group of robots, and also carrying out other actions with vulnerabilities of multiagent algorithms without obviously identified signs of invasion of robots-saboteurs. The model of information security is developed, in which robots-agents work out trust levels to each other analyzing the events occurring in the system. The idea of trust model consists in the analysis of transferred information by each robot and the executed actions of other members in a group, comparison of chosen decision on iteration step k with objective function of the group. Distinctive feature of the trust model in comparison with the closest analogue - Buddy Security Model in which the exchange between the agents security tokens is done — is involvement of the time factor during which agents have to "prove" by their actions the usefulness in achievement of a common goal to members of the group. Variants of this model realization and ways of an assessment of trust levels for agents in view of the security policy accepted in the group are proposed.

COMPARISON OF CLASSICAL AND INTERACTIVE MULTI-ROBOT EXPLORATION STRATEGIES IN POPULATED ENVIRONMENTS

Directory of Open Access Journals (Sweden)

Nassim Kalde

2015-06-01

Full Text Available Multi-robot exploration consists in coordinating robots for mapping an unknown environment. It raises several issues concerning task allocation, robot control, path planning and communication. We study exploration in populated environments, in which pedestrian flows can severely impact performances. However, humans have adaptive skills for taking advantage of these flows while moving. Therefore, in order to exploit these human abilities, we propose a novel exploration strategy that explicitly allows for human-robot interactions. Our model for exploration in populated environments combines the classical frontier-based strategy with our interactive approach. We implement interactions where robots can locally choose a human guide to follow and define a parametric heuristic to balance interaction and frontier assignments. Finally, we evaluate to which extent human presence impacts our exploration model in terms of coverage ratio, travelled distance and elapsed time to completion.

Primitive-path statistics of entangled polymers: mapping multi-chain simulations onto single-chain mean-field models

International Nuclear Information System (INIS)

Steenbakkers, Rudi J A; Schieber, Jay D; Tzoumanekas, Christos; Li, Ying; Liu, Wing Kam; Kröger, Martin

2014-01-01

We present a method to map the full equilibrium distribution of the primitive-path (PP) length, obtained from multi-chain simulations of polymer melts, onto a single-chain mean-field ‘target’ model. Most previous works used the Doi–Edwards tube model as a target. However, the average number of monomers per PP segment, obtained from multi-chain PP networks, has consistently shown a discrepancy of a factor of two with respect to tube-model estimates. Part of the problem is that the tube model neglects fluctuations in the lengths of PP segments, the number of entanglements per chain and the distribution of monomers among PP segments, while all these fluctuations are observed in multi-chain simulations. Here we use a recently proposed slip-link model, which includes fluctuations in all these variables as well as in the spatial positions of the entanglements. This turns out to be essential to obtain qualitative and quantitative agreement with the equilibrium PP-length distribution obtained from multi-chain simulations. By fitting this distribution, we are able to determine two of the three parameters of the model, which govern its equilibrium properties. This mapping is executed for four different linear polymers and for different molecular weights. The two parameters are found to depend on chemistry, but not on molecular weight. The model predicts a constant plateau modulus minus a correction inversely proportional to molecular weight. The value for well-entangled chains, with the parameters determined ab initio, lies in the range of experimental data for the materials investigated. (paper)

Obstacle traversal and self-righting of bio-inspired robots reveal the physics of multi-modal locomotion

Science.gov (United States)

Li, Chen; Fearing, Ronald; Full, Robert

Most animals move in nature in a variety of locomotor modes. For example, to traverse obstacles like dense vegetation, cockroaches can climb over, push across, reorient their bodies to maneuver through slits, or even transition among these modes forming diverse locomotor pathways; if flipped over, they can also self-right using wings or legs to generate body pitch or roll. By contrast, most locomotion studies have focused on a single mode such as running, walking, or jumping, and robots are still far from capable of life-like, robust, multi-modal locomotion in the real world. Here, we present two recent studies using bio-inspired robots, together with new locomotion energy landscapes derived from locomotor-environment interaction physics, to begin to understand the physics of multi-modal locomotion. (1) Our experiment of a cockroach-inspired legged robot traversing grass-like beam obstacles reveals that, with a terradynamically ``streamlined'' rounded body like that of the insect, robot traversal becomes more probable by accessing locomotor pathways that overcome lower potential energy barriers. (2) Our experiment of a cockroach-inspired self-righting robot further suggests that body vibrations are crucial for exploring locomotion energy landscapes and reaching lower barrier pathways. Finally, we posit that our new framework of locomotion energy landscapes holds promise to better understand and predict multi-modal biological and robotic movement.

Multi-robot caravanning

KAUST Repository

Denny, Jory; Giese, Andrew; Mahadevan, Aditya; Marfaing, Arnaud; Glockenmeier, Rachel; Revia, Colton; Rodriguez, Samuel; Amato, Nancy M.

2013-01-01

of waypoints. At the heart of our algorithm is the use of leader election to efficiently exploit the unique environmental knowledge available to each robot in order to plan paths for the group, which makes it general enough to work with robots that have

Parallel algorithms for simulating continuous time Markov chains

Science.gov (United States)

Nicol, David M.; Heidelberger, Philip

1992-01-01

We have previously shown that the mathematical technique of uniformization can serve as the basis of synchronization for the parallel simulation of continuous-time Markov chains. This paper reviews the basic method and compares five different methods based on uniformization, evaluating their strengths and weaknesses as a function of problem characteristics. The methods vary in their use of optimism, logical aggregation, communication management, and adaptivity. Performance evaluation is conducted on the Intel Touchstone Delta multiprocessor, using up to 256 processors.

Virtual Sensor for Kinematic Estimation of Flexible Links in Parallel Robots.

Science.gov (United States)

Bengoa, Pablo; Zubizarreta, Asier; Cabanes, Itziar; Mancisidor, Aitziber; Pinto, Charles; Mata, Sara

2017-08-23

The control of flexible link parallel manipulators is still an open area of research, endpoint trajectory tracking being one of the main challenges in this type of robot. The flexibility and deformations of the limbs make the estimation of the Tool Centre Point (TCP) position a challenging one. Authors have proposed different approaches to estimate this deformation and deduce the location of the TCP. However, most of these approaches require expensive measurement systems or the use of high computational cost integration methods. This work presents a novel approach based on a virtual sensor which can not only precisely estimate the deformation of the flexible links in control applications (less than 2% error), but also its derivatives (less than 6% error in velocity and 13% error in acceleration) according to simulation results. The validity of the proposed Virtual Sensor is tested in a Delta Robot, where the position of the TCP is estimated based on the Virtual Sensor measurements with less than a 0.03% of error in comparison with the flexible approach developed in ADAMS Multibody Software.

Research on Multi - Person Parallel Modeling Method Based on Integrated Model Persistent Storage

Science.gov (United States)

Qu, MingCheng; Wu, XiangHu; Tao, YongChao; Liu, Ying

2018-03-01

This paper mainly studies the multi-person parallel modeling method based on the integrated model persistence storage. The integrated model refers to a set of MDDT modeling graphics system, which can carry out multi-angle, multi-level and multi-stage description of aerospace general embedded software. Persistent storage refers to converting the data model in memory into a storage model and converting the storage model into a data model in memory, where the data model refers to the object model and the storage model is a binary stream. And multi-person parallel modeling refers to the need for multi-person collaboration, the role of separation, and even real-time remote synchronization modeling.

Multi-dimensional quasitoeplitz Markov chains

Directory of Open Access Journals (Sweden)

Alexander N. Dudin

1999-01-01

Full Text Available This paper deals with multi-dimensional quasitoeplitz Markov chains. We establish a sufficient equilibrium condition and derive a functional matrix equation for the corresponding vector-generating function, whose solution is given algorithmically. The results are demonstrated in the form of examples and applications in queues with BMAP-input, which operate in synchronous random environment.

Kinematic Model of NAO Humanoid Robot

Directory of Open Access Journals (Sweden)

Miloš D. Jovanović

2014-06-01

Full Text Available This paper presents synthesis of kinematic model of NAO humanoid robot of Aldebaran Robotics. NAO humanoid robot has complex kinematic structure with 25 active degrees of freedom (DOF. Humanoid system is formed through 5 mutually depended kinematic chains. After that we applied standard aspects of kinematic chains synthesis and Denavit-Hartenberg parameters of each of 5 chains of robotic structure were introduced. Also, mutual relationships between chains were described, as well as their physical and structural dependence. Generated kinematic model will be the starting point for further dynamical modeling of NAO humanoid robot and motion synthesis on actual platform.

Design and Analysis of a Bio-Inspired Wire-Driven Multi-Section Flexible Robot

Directory of Open Access Journals (Sweden)

Zheng Li

2013-04-01

Full Text Available This paper presents a bio-inspired wire-driven multi-section flexible robot. It is inspired by the snake skeleton and octopus arm muscle arrangements. The robot consists of three sections and each section is made up of several identical vertebras, which are articulated by both spherical joints and a flexible backbone. Each section is driven by two groups of wires, controlling the bending motion in X and Y directions. This design integrates the serpentine robots' structure and the continuum robots' actuation. As a result, it is more compact than traditional serpentine robots and has a higher positioning accuracy than typical continuum soft robots, such as OctArm V. A Kinematics model and a workspace model of the robot are developed based on the piece wise constant curvature assumption. To evaluate the design, a prototype is built and experiments are carried out. The average distal end positioning error is less than 4%. Characteristics of the wire-driven robot are also discussed, including the leverage effect and the manipulability under constraint. These features makes the proposed robot well suited to confined spaces, especially for working in minimally invasive surgery, nuclear reactor pipelines, disaster debris, etc.

Control system for a multi-joint inspection robot

International Nuclear Information System (INIS)

Asano, K.

1984-01-01

Remote systems, in which a human operator in a safe zone determines pertinent circumstances and makes decisions on work procedures, while a robot does direct work in hazardous environments, have been becoming more and more important in accordance with the increase in nuclear facilities. In such remote systems, to perform tasks which are merely ambiguously defined beforehand, it is very important that the systems have the ability to execute desired tasks easily and immediately without any programming or teaching work on the spot. A control system, named Self Approach System (SAS), for a multi-joint inspection robot has been developed as a key component in a remote inspection system for use in physically difficult or dangerous environments. It has 8 joints and 17 degrees-of-freedom and was designed taking many of the above points into account. This paper describes SAS details

Parallel kinematics robot with five legs

NARCIS (Netherlands)

Lambert, P.

2011-01-01

Robot with multiple degrees of freedom comprising five legs (2) linked at a first of their ends to a base ( 3), and at a second of their ends opposite to the first ends to a mobile platform (4), which platform carries at least one tool (5, 6, 121, 12 "), and wherein the robot further comprises an

Multi-robot system using low-cost infrared sensors

Directory of Open Access Journals (Sweden)

Anubhav Kakkar

2013-03-01

Full Text Available This paper presents a proposed set of the novel technique, methods, and algorithm for simultaneous path planning, area exploration, area retrieval, obstacle avoidance, object detection, and object retrieval   autonomously by a multi-robot system. The proposed methods and algorithms are built considering the use of low cost infrared sensors with the ultimate function of efficiently exploring the given unknown area and simultaneously identifying desired objects by analyzing the physical characteristics of several of the objects that come across during exploration. In this paper, we have explained the scenario by building a coordinative multi-robot system consisting of two autonomously operated robots equipped with low-cost and low-range infrared sensors to perform the assigned task by analyzing some of the sudden changes in their environment. Along with identifying and retrieving the desired object, the proposed methodology also provide an inclusive analysis of the area being explored. The novelties presented in the paper may significantly provide a cost-effective solution to the problem of area exploration and finding a known object in an unknown environment by demonstrating an innovative approach of using the infrared sensors instead of high cost long range sensors and cameras. Additionally, the methodology provides a speedy and uncomplicated method of traversing a complicated arena while performing all the necessary and inter-related tasks of avoiding the obstacles, analyzing the area as well as objects, and reconstructing the area using all these information collected and interpreted for an unknown environment. The methods and algorithms proposed are simulated over a complex arena to depict the operations and manually tested over a physical environment which provided 78% correct results with respect to various complex parameters set randomly.

Trajectory control of robot manipulators with closed-kinematic chain mechanism

Science.gov (United States)

Nguyen, Charles C.; Pooran, Farhad J.; Premack, Timothy

1987-01-01

The problem of Cartesian trajectory control of a closed-kinematic chain mechanism robot manipulator, recently built at CAIR to study the assembly of NASA hardware for the future Space Station, is considered. The study is performed by both computer simulation and experimentation for tracking of three different paths: a straight line, a sinusoid, and a circle. Linearization and pole placement methods are employed to design controller gains. Results show that the controllers are robust and there are good agreements between simulation and experimentation. The results also show excellent tracking quality and small overshoots.

An Inexpensive Method for Kinematic Calibration of a Parallel Robot by Using One Hand-Held Camera as Main Sensor

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Ricardo Carelli

2013-08-01

Full Text Available This paper presents a novel method for the calibration of a parallel robot, which allows a more accurate configuration instead of a configuration based on nominal parameters. It is used, as the main sensor with one camera installed in the robot hand that determines the relative position of the robot with respect to a spherical object fixed in the working area of the robot. The positions of the end effector are related to the incremental positions of resolvers of the robot motors. A kinematic model of the robot is used to find a new group of parameters, which minimizes errors in the kinematic equations. Additionally, properties of the spherical object and intrinsic camera parameters are utilized to model the projection of the object in the image and thereby improve spatial measurements. Finally, several working tests, static and tracking tests are executed in order to verify how the robotic system behaviour improves by using calibrated parameters against nominal parameters. In order to emphasize that, this proposed new method uses neither external nor expensive sensor. That is why new robots are useful in teaching and research activities.

The design of multi-core DSP parallel model based on message passing and multi-level pipeline

Science.gov (United States)

Niu, Jingyu; Hu, Jian; He, Wenjing; Meng, Fanrong; Li, Chuanrong

2017-10-01

Currently, the design of embedded signal processing system is often based on a specific application, but this idea is not conducive to the rapid development of signal processing technology. In this paper, a parallel processing model architecture based on multi-core DSP platform is designed, and it is mainly suitable for the complex algorithms which are composed of different modules. This model combines the ideas of multi-level pipeline parallelism and message passing, and summarizes the advantages of the mainstream model of multi-core DSP (the Master-Slave model and the Data Flow model), so that it has better performance. This paper uses three-dimensional image generation algorithm to validate the efficiency of the proposed model by comparing with the effectiveness of the Master-Slave and the Data Flow model.

Reference trajectory tracking for a multi-DOF robot arm

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Krasňanský Róbert

2015-12-01

Full Text Available This paper presents the problem of tracking the generated reference trajectory by the simulation model of a multi-DOF robot arm. The kinematic transformation between task space and joint configuration coordinates is nonlinear and configuration dependent. To obtain the solution of the forward kinematics problem, the homogeneous transformation matrix is used. A solution to the inverse kinematics is a vector of joint configuration coordinates calculated using of pseudoinverse Jacobian technique. These coordinates correspond to a set of task space coordinates. The algorithm is presented which uses iterative solution and is simplified by considering stepper motors in robot arm joints. The reference trajectory in Cartesian coordinate system is generated on-line by the signal generator previously developed in MS Excel. Dynamic Data Exchange communication protocol allows sharing data with Matlab-Simulink. These data represent the reference tracking trajectory of the end effector. Matlab-Simulink software is used to calculate the representative joint rotations. The proposed algorithm is demonstrated experimentally on the model of 7-DOF robot arm system.

Building a ROS-Based Testbed for Realistic Multi-Robot Simulation: Taking the Exploration as an Example

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Zhi Yan

2017-09-01

Full Text Available While the robotics community agrees that the benchmarking is of high importance to objectively compare different solutions, there are only few and limited tools to support it. To address this issue in the context of multi-robot systems, we have defined a benchmarking process based on experimental designs, which aimed at improving the reproducibility of experiments by making explicit all elements of a benchmark such as parameters, measurements and metrics. We have also developed a ROS (Robot Operating System-based testbed with the goal of making it easy for users to validate, benchmark, and compare different algorithms including coordination strategies. Our testbed uses the MORSE (Modular OpenRobots Simulation Engine simulator for realistic simulation and a computer cluster for decentralized computation. In this paper, we present our testbed in details with the architecture and infrastructure, the issues encountered in implementing the infrastructure, and the automation of the deployment. We also report a series of experiments on multi-robot exploration, in order to demonstrate the capabilities of our testbed.

An Efficient Parallel Multi-Scale Segmentation Method for Remote Sensing Imagery

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Haiyan Gu

2018-04-01

Full Text Available Remote sensing (RS image segmentation is an essential step in geographic object-based image analysis (GEOBIA to ultimately derive “meaningful objects”. While many segmentation methods exist, most of them are not efficient for large data sets. Thus, the goal of this research is to develop an efficient parallel multi-scale segmentation method for RS imagery by combining graph theory and the fractal net evolution approach (FNEA. Specifically, a minimum spanning tree (MST algorithm in graph theory is proposed to be combined with a minimum heterogeneity rule (MHR algorithm that is used in FNEA. The MST algorithm is used for the initial segmentation while the MHR algorithm is used for object merging. An efficient implementation of the segmentation strategy is presented using data partition and the “reverse searching-forward processing” chain based on message passing interface (MPI parallel technology. Segmentation results of the proposed method using images from multiple sensors (airborne, SPECIM AISA EAGLE II, WorldView-2, RADARSAT-2 and different selected landscapes (residential/industrial, residential/agriculture covering four test sites indicated its efficiency in accuracy and speed. We conclude that the proposed method is applicable and efficient for the segmentation of a variety of RS imagery (airborne optical, satellite optical, SAR, high-spectral, while the accuracy is comparable with that of the FNEA method.

Multi-criteria decision making approaches for green supply chains

NARCIS (Netherlands)

Banasik, Aleksander; Bloemhof-Ruwaard, Jacqueline M.; Kanellopoulos, Argyris; Claassen, G.D.H.; Vorst, van der Jack G.A.J.

2016-01-01

Designing Green Supply Chains (GSCs) requires complex decision-support models that can deal with multiple dimensions of sustainability while taking into account specific characteristics of products and their supply chain. Multi-Criteria Decision Making (MCDM) approaches can be used to quantify

Advanced mechanics in robotic systems

CERN Document Server

Nava Rodríguez, Nestor Eduardo

2011-01-01

Illustrates original and ambitious mechanical designs and techniques for the development of new robot prototypes Includes numerous figures, tables and flow charts Discusses relevant applications in robotics fields such as humanoid robots, robotic hands, mobile robots, parallel manipulators and human-centred robots

A Soft Parallel Kinematic Mechanism.

Science.gov (United States)

White, Edward L; Case, Jennifer C; Kramer-Bottiglio, Rebecca

2018-02-01

In this article, we describe a novel holonomic soft robotic structure based on a parallel kinematic mechanism. The design is based on the Stewart platform, which uses six sensors and actuators to achieve full six-degree-of-freedom motion. Our design is much less complex than a traditional platform, since it replaces the 12 spherical and universal joints found in a traditional Stewart platform with a single highly deformable elastomer body and flexible actuators. This reduces the total number of parts in the system and simplifies the assembly process. Actuation is achieved through coiled-shape memory alloy actuators. State observation and feedback is accomplished through the use of capacitive elastomer strain gauges. The main structural element is an elastomer joint that provides antagonistic force. We report the response of the actuators and sensors individually, then report the response of the complete assembly. We show that the completed robotic system is able to achieve full position control, and we discuss the limitations associated with using responsive material actuators. We believe that control demonstrated on a single body in this work could be extended to chains of such bodies to create complex soft robots.

Robots, multi-user virtual environments and healthcare: synergies for future directions.

Science.gov (United States)

Moon, Ajung; Grajales, Francisco J; Van der Loos, H F Machiel

2011-01-01

The adoption of technology in healthcare over the last twenty years has steadily increased, particularly as it relates to medical robotics and Multi-User Virtual Environments (MUVEs) such as Second Life. Both disciplines have been shown to improve the quality of care and have evolved, for the most part, in isolation from each other. In this paper, we present four synergies between medical robotics and MUVEs that have the potential to decrease resource utilization and improve the quality of healthcare delivery. We conclude with some foreseeable barriers and future research directions for researchers in these fields.

Open middleware for robotics

CSIR Research Space (South Africa)

Namoshe, M

2008-12-01

Full Text Available and their technologies within the field of multi-robot systems to ease the difficulty of realizing robot applications. And lastly, an example of algorithm development for multi-robot co-operation using one of the discussed software architecture is presented...

Adaptive heterogeneous multi-robot teams

Energy Technology Data Exchange (ETDEWEB)

Parker, L.E.

1998-11-01

This research addresses the problem of achieving fault tolerant cooperation within small- to medium-sized teams of heterogeneous mobile robots. The author describes a novel behavior-based, fully distributed architecture, called ALLIANCE, that utilizes adaptive action selection to achieve fault tolerant cooperative control in robot missions involving loosely coupled, largely independent tasks. The robots in this architecture possess a variety of high-level functions that they can perform during a mission, and must at all times select an appropriate action based on the requirements of the mission, the activities of other robots, the current environmental conditions, and their own internal states. Since such cooperative teams often work in dynamic and unpredictable environments, the software architecture allows the team members to respond robustly and reliably to unexpected environmental changes and modifications in the robot team that may occur due to mechanical failure, the learning of new skills, or the addition or removal of robots from the team by human intervention. After presenting ALLIANCE, the author describes in detail the experimental results of an implementation of this architecture on a team of physical mobile robots performing a cooperative box pushing demonstration. These experiments illustrate the ability of ALLIANCE to achieve adaptive, fault-tolerant cooperative control amidst dynamic changes in the capabilities of the robot team.

CRUX: A compliant robotic upper-extremity exosuit for lightweight, portable, multi-joint muscular augmentation.

Science.gov (United States)

Lessard, Steven; Pansodtee, Pattawong; Robbins, Ash; Baltaxe-Admony, Leya Breanna; Trombadore, James M; Teodorescu, Mircea; Agogino, Adrian; Kurniawan, Sri

2017-07-01

Wearable robots can potentially offer their users enhanced stability and strength. These augmentations are ideally designed to actuate harmoniously with the user's movements and provide extra force as needed. The creation of such robots, however, is particularly challenging due to the underlying complexity of the human body. In this paper, we present a compliant, robotic exosuit for upper extremities called CRUX. This exosuit, inspired by tensegrity models of the human arm, features a lightweight (1.3 kg), flexible multi-joint design for portable augmentation. We also illustrate how CRUX maintains the full range of motion of the upper-extremities for its users while providing multi-DoF strength amplification to the major muscles of the arm, as evident by tracking the heart rate of an individual exercising said arm. Exosuits such as CRUX may be useful in physical therapy and in extreme environments where users are expected to exert their bodies to the fullest extent.

Analysis of flow distribution instability in parallel thin rectangular multi-channel system

Energy Technology Data Exchange (ETDEWEB)

Xia, G.L. [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an City 710049 (China); Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, Harbin Engineering University, Harbin City 150001 (China); Su, G.H., E-mail: ghsu@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an City 710049 (China); Peng, M.J. [Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, Harbin Engineering University, Harbin City 150001 (China)

2016-08-15

Highlights: • Flow distribution instability in parallel thin rectangular multi-channel system is studied using RELAP5 codes. • Flow excursion may bring parallel heating channel into the density wave oscillations region. • Flow distribution instability is more likely to happen at low power/flow ratio conditions. • The increase of channel number will not affect the flow distribution instability boundary. • Asymmetry inlet throttling and heating will make system more unstable. - Abstract: The flow distribution instability in parallel thin rectangular multi-channel system has been researched in the present study. The research model of parallel channel system is established by using RELAP5/MOD3.4 codes. The transient process of flow distribution instability is studied at imposed inlet mass flow rate and imposed pressure drop conditions. The influence of heating power, mass flow rate, system pressure and channel number on flow distribution instability are analyzed. Furthermore, the flow distribution instability of parallel two-channel system under asymmetric inlet throttling and heating power is studied. The results show that, if multi-channel system operates at the negative slope region of channel ΔP–G curve, small disturbance in pressure drop will lead to flow redistribution between parallel channels. Flow excursion may bring the operating point of heating channel into the density-wave oscillations region, this will result in out-phase or in-phase flow oscillations. Flow distribution instability is more likely to happen at low power/flow ratio conditions, the stability of parallel channel system increases with system pressure, the channel number has a little effect on system stability, but the asymmetry inlet throttling or heating power will make the system more unstable.

Novel Door-opening Method for Six-legged Robots Based on Only Force Sensing

Science.gov (United States)

Chen, Zhi-Jun; Gao, Feng; Pan, Yang

2017-09-01

Current door-opening methods are mainly developed on tracked, wheeled and biped robots by applying multi-DOF manipulators and vision systems. However, door-opening methods for six-legged robots are seldom studied, especially using 0-DOF tools to operate and only force sensing to detect. A novel door-opening method for six-legged robots is developed and implemented to the six-parallel-legged robot. The kinematic model of the six-parallel-legged robot is established and the model of measuring the positional relationship between the robot and the door is proposed. The measurement model is completely based on only force sensing. The real-time trajectory planning method and the control strategy are designed. The trajectory planning method allows the maximum angle between the sagittal axis of the robot body and the normal line of the door plane to be 45º. A 0-DOF tool mounted to the robot body is applied to operate. By integrating with the body, the tool has 6 DOFs and enough workspace to operate. The loose grasp achieved by the tool helps release the inner force in the tool. Experiments are carried out to validate the method. The results show that the method is effective and robust in opening doors wider than 1 m. This paper proposes a novel door-opening method for six-legged robots, which notably uses a 0-DOF tool and only force sensing to detect and open the door.

Performance impact of mutation operators of a subpopulation-based genetic algorithm for multi-robot task allocation problems.

Science.gov (United States)

Liu, Chun; Kroll, Andreas

2016-01-01

Multi-robot task allocation determines the task sequence and distribution for a group of robots in multi-robot systems, which is one of constrained combinatorial optimization problems and more complex in case of cooperative tasks because they introduce additional spatial and temporal constraints. To solve multi-robot task allocation problems with cooperative tasks efficiently, a subpopulation-based genetic algorithm, a crossover-free genetic algorithm employing mutation operators and elitism selection in each subpopulation, is developed in this paper. Moreover, the impact of mutation operators (swap, insertion, inversion, displacement, and their various combinations) is analyzed when solving several industrial plant inspection problems. The experimental results show that: (1) the proposed genetic algorithm can obtain better solutions than the tested binary tournament genetic algorithm with partially mapped crossover; (2) inversion mutation performs better than other tested mutation operators when solving problems without cooperative tasks, and the swap-inversion combination performs better than other tested mutation operators/combinations when solving problems with cooperative tasks. As it is difficult to produce all desired effects with a single mutation operator, using multiple mutation operators (including both inversion and swap) is suggested when solving similar combinatorial optimization problems.

Robotic intelligence kernel

Science.gov (United States)

Bruemmer, David J [Idaho Falls, ID

2009-11-17

A robot platform includes perceptors, locomotors, and a system controller. The system controller executes a robot intelligence kernel (RIK) that includes a multi-level architecture and a dynamic autonomy structure. The multi-level architecture includes a robot behavior level for defining robot behaviors, that incorporate robot attributes and a cognitive level for defining conduct modules that blend an adaptive interaction between predefined decision functions and the robot behaviors. The dynamic autonomy structure is configured for modifying a transaction capacity between an operator intervention and a robot initiative and may include multiple levels with at least a teleoperation mode configured to maximize the operator intervention and minimize the robot initiative and an autonomous mode configured to minimize the operator intervention and maximize the robot initiative. Within the RIK at least the cognitive level includes the dynamic autonomy structure.

Multi-Robot Search for a Moving Target: Integrating World Modeling, Task Assignment and Context

Science.gov (United States)

2016-12-01

Gemignani1, Daniele Nardi1 Abstract— In this paper, we address coordination within a team of cooperative autonomous robots that need to accomplish a common... cooperate to achieve a common goal. During the last years, the approaches to Multi-Robot Systems have been noticed and categorized in different survey...the environment). To highlight how our contribution compares to existing approaches, we categorize existing works on Fig. 2 by con - sidering their

A neuro-inspired spike-based PID motor controller for multi-motor robots with low cost FPGAs.

Science.gov (United States)

Jimenez-Fernandez, Angel; Jimenez-Moreno, Gabriel; Linares-Barranco, Alejandro; Dominguez-Morales, Manuel J; Paz-Vicente, Rafael; Civit-Balcells, Anton

2012-01-01

In this paper we present a neuro-inspired spike-based close-loop controller written in VHDL and implemented for FPGAs. This controller has been focused on controlling a DC motor speed, but only using spikes for information representation, processing and DC motor driving. It could be applied to other motors with proper driver adaptation. This controller architecture represents one of the latest layers in a Spiking Neural Network (SNN), which implements a bridge between robotics actuators and spike-based processing layers and sensors. The presented control system fuses actuation and sensors information as spikes streams, processing these spikes in hard real-time, implementing a massively parallel information processing system, through specialized spike-based circuits. This spike-based close-loop controller has been implemented into an AER platform, designed in our labs, that allows direct control of DC motors: the AER-Robot. Experimental results evidence the viability of the implementation of spike-based controllers, and hardware synthesis denotes low hardware requirements that allow replicating this controller in a high number of parallel controllers working together to allow a real-time robot control.

Modified bug-1 algorithm based strategy for obstacle avoidance in multi robot system

Directory of Open Access Journals (Sweden)

Kandathil Jom J.

2018-01-01

Full Text Available One of the primary ability of an intelligent mobile robot system is obstacle avoidance. BUG algorithms are classic examples of the algorithms used for achieving obstacle avoidance. Unlike many other planning algorithms based on global knowledge, BUG algorithms assume only local knowledge of the environment and a global goal. Among the variations of the BUG algorithms that prevail, BUG-0, BUG-1 and BUG-2 are the more prominent versions. The exhaustive search algorithm present in BUG-1 makes it more reliable and safer for practical applications. Overall, this provides a more predictable and dependable performance. Hence, the essential focus in this paper is on implementing the BUG-1 algorithm across a group of robots to move them from a start location to a target location. The results are compared with the results from BUG-1 algorithm implemented on a single robot. The strategy developed in this work reduces the time involved in moving the robots from starting location to the target location. Further, the paper shows that the total distance covered by each robot in a multi robot-system is always lesser than or equal to that travelled by a single robot executing the same problem.

Toward a model framework of generalized parallel componential processing of multi-symbol numbers.

Science.gov (United States)

Huber, Stefan; Cornelsen, Sonja; Moeller, Korbinian; Nuerk, Hans-Christoph

2015-05-01

In this article, we propose and evaluate a new model framework of parallel componential multi-symbol number processing, generalizing the idea of parallel componential processing of multi-digit numbers to the case of negative numbers by considering the polarity signs similar to single digits. In a first step, we evaluated this account by defining and investigating a sign-decade compatibility effect for the comparison of positive and negative numbers, which extends the unit-decade compatibility effect in 2-digit number processing. Then, we evaluated whether the model is capable of accounting for previous findings in negative number processing. In a magnitude comparison task, in which participants had to single out the larger of 2 integers, we observed a reliable sign-decade compatibility effect with prolonged reaction times for incompatible (e.g., -97 vs. +53; in which the number with the larger decade digit has the smaller, i.e., negative polarity sign) as compared with sign-decade compatible number pairs (e.g., -53 vs. +97). Moreover, an analysis of participants' eye fixation behavior corroborated our model of parallel componential processing of multi-symbol numbers. These results are discussed in light of concurrent theoretical notions about negative number processing. On the basis of the present results, we propose a generalized integrated model framework of parallel componential multi-symbol processing. (c) 2015 APA, all rights reserved).

Distributed Fault Detection and Isolation for Flocking in a Multi-robot System with Imperfect Communication

Directory of Open Access Journals (Sweden)

Shao Shiliang

2014-06-01

Full Text Available In this paper, we focus on distributed fault detection and isolation (FDI for a multi-robot system where multiple robots execute a flocking task. Firstly, we propose a fault detection method based on the local-information-exchange and sensor-measurement technologies to cover cases of both perfect communication and imperfect communication. The two detection technologies can be adaptively selected according to the packet loss rate (PLR. Secondly, we design a fault isolation method, considering a situation in which faulty robots still influence the behaviours of other robots. Finally, a complete FDI scheme, based on the proposed detection and isolation methods, is simulated in various scenarios. The results demonstrate that our FDI scheme is effective.

A New Approach of Multi-robot Cooperative Pursuit Based on Association Rule Data Mining

Directory of Open Access Journals (Sweden)

Jun Li

2010-02-01

Full Text Available An approach of cooperative hunting for multiple mobile targets by multi-robot is presented, which divides the pursuit process into forming the pursuit teams and capturing the targets. The data sets of attribute relationship is built by consulting all of factors about capturing evaders, then the interesting rules can be found by data mining from the data sets to build the pursuit teams. Through doping out the positions of targets, the pursuit game can be transformed into multi-robot path planning. Reinforcement learning is used to find the best path. The simulation results show that the mobile evaders can be captured effectively and efficiently, and prove the feasibility and validity of the given algorithm under a dynamic environment.

A New Approach of Multi-Robot Cooperative Pursuit Based on Association Rule Data Mining

Directory of Open Access Journals (Sweden)

Jun Li

2009-12-01

Full Text Available An approach of cooperative hunting for multiple mobile targets by multi-robot is presented, which divides the pursuit process into forming the pursuit teams and capturing the targets. The data sets of attribute relationship is built by consulting all of factors about capturing evaders, then the interesting rules can be found by data mining from the data sets to build the pursuit teams. Through doping out the positions of targets, the pursuit game can be transformed into multi-robot path planning. Reinforcement learning is used to find the best path. The simulation results show that the mobile evaders can be captured effectively and efficiently, and prove the feasibility and validity of the given algorithm under a dynamic environment.

Semi-autonomous exploration of multi-floor buildings with a legged robot

Science.gov (United States)

Wenger, Garrett J.; Johnson, Aaron M.; Taylor, Camillo J.; Koditschek, Daniel E.

2015-05-01

This paper presents preliminary results of a semi-autonomous building exploration behavior using the hexapedal robot RHex. Stairwells are used in virtually all multi-floor buildings, and so in order for a mobile robot to effectively explore, map, clear, monitor, or patrol such buildings it must be able to ascend and descend stairwells. However most conventional mobile robots based on a wheeled platform are unable to traverse stairwells, motivating use of the more mobile legged machine. This semi-autonomous behavior uses a human driver to provide steering input to the robot, as would be the case in, e.g., a tele-operated building exploration mission. The gait selection and transitions between the walking and stair climbing gaits are entirely autonomous. This implementation uses an RGBD camera for stair acquisition, which offers several advantages over a previously documented detector based on a laser range finder, including significantly reduced acquisition time. The sensor package used here also allows for considerable expansion of this behavior. For example, complete automation of the building exploration task driven by a mapping algorithm and higher level planner is presently under development.

Fused Smart Sensor Network for Multi-Axis Forward Kinematics Estimation in Industrial Robots

Directory of Open Access Journals (Sweden)

Rene de Jesus Romero-Troncoso

2011-04-01

Full Text Available Flexible manipulator robots have a wide industrial application. Robot performance requires sensing its position and orientation adequately, known as forward kinematics. Commercially available, motion controllers use high-resolution optical encoders to sense the position of each joint which cannot detect some mechanical deformations that decrease the accuracy of the robot position and orientation. To overcome those problems, several sensor fusion methods have been proposed but at expenses of high-computational load, which avoids the online measurement of the joint’s angular position and the online forward kinematics estimation. The contribution of this work is to propose a fused smart sensor network to estimate the forward kinematics of an industrial robot. The developed smart processor uses Kalman filters to filter and to fuse the information of the sensor network. Two primary sensors are used: an optical encoder, and a 3-axis accelerometer. In order to obtain the position and orientation of each joint online a field-programmable gate array (FPGA is used in the hardware implementation taking advantage of the parallel computation capabilities and reconfigurability of this device. With the aim of evaluating the smart sensor network performance, three real-operation-oriented paths are executed and monitored in a 6-degree of freedom robot.

Fused smart sensor network for multi-axis forward kinematics estimation in industrial robots.

Science.gov (United States)

Rodriguez-Donate, Carlos; Osornio-Rios, Roque Alfredo; Rivera-Guillen, Jesus Rooney; Romero-Troncoso, Rene de Jesus

2011-01-01

Flexible manipulator robots have a wide industrial application. Robot performance requires sensing its position and orientation adequately, known as forward kinematics. Commercially available, motion controllers use high-resolution optical encoders to sense the position of each joint which cannot detect some mechanical deformations that decrease the accuracy of the robot position and orientation. To overcome those problems, several sensor fusion methods have been proposed but at expenses of high-computational load, which avoids the online measurement of the joint's angular position and the online forward kinematics estimation. The contribution of this work is to propose a fused smart sensor network to estimate the forward kinematics of an industrial robot. The developed smart processor uses Kalman filters to filter and to fuse the information of the sensor network. Two primary sensors are used: an optical encoder, and a 3-axis accelerometer. In order to obtain the position and orientation of each joint online a field-programmable gate array (FPGA) is used in the hardware implementation taking advantage of the parallel computation capabilities and reconfigurability of this device. With the aim of evaluating the smart sensor network performance, three real-operation-oriented paths are executed and monitored in a 6-degree of freedom robot.

Sistema multi-robot para localización e identificación de vehículos

Directory of Open Access Journals (Sweden)

C. Sagues

2012-01-01

Full Text Available Resumen: En este trabajo se presenta un sistema multi-robot para localización e identificación de vehículos que están estacionados en un recinto abierto o cerrado. El sistema realiza una planificación a priori y una asignación de tareas a los miembros del equipo optimizando el tiempo de la misión. El equipo de robots está dotado de sensores de visión que permiten la localización de los vehículos y la identificación de su matrícula. El controlador de movimiento de cada robot utiliza un sensor láser para el posicionamiento frente al vehículo a identificar y un sistema de control basado en visión realiza el posicionamiento preciso para la adquisición de la imagen de la matrícula que permita su posterior identificación. El sistema multi-robot dispone de capacidad de comunicaciones entre ellos y con una estación central de mando, con la que se intercambian comandos e incidencias y eventualmente datos, con restricciones de tiempo real. Los sensores utilizados están comercialmente disponibles y los algoritmos han sido desarrollados por el grupo Robótica, Percepción y Tiempo Real de la Universidad de Zaragoza en el marco de proyectos financiados por el Ministerio de Ciencia e Innovación. Integra diversas tecnologías de planificación, navegación, percepción y comunicaciones, adaptadas en el proyecto a la aplicación concreta. Palabras clave: Sistemas multi-robot, Robótica móvil, Navegación, Planificación y asignación de tareas, Protocolos de comunicación, Visión porcomputador, Tiempo real

Spatial data analytics on heterogeneous multi- and many-core parallel architectures using python

Science.gov (United States)

Laura, Jason R.; Rey, Sergio J.

2017-01-01

Parallel vector spatial analysis concerns the application of parallel computational methods to facilitate vector-based spatial analysis. The history of parallel computation in spatial analysis is reviewed, and this work is placed into the broader context of high-performance computing (HPC) and parallelization research. The rise of cyber infrastructure and its manifestation in spatial analysis as CyberGIScience is seen as a main driver of renewed interest in parallel computation in the spatial sciences. Key problems in spatial analysis that have been the focus of parallel computing are covered. Chief among these are spatial optimization problems, computational geometric problems including polygonization and spatial contiguity detection, the use of Monte Carlo Markov chain simulation in spatial statistics, and parallel implementations of spatial econometric methods. Future directions for research on parallelization in computational spatial analysis are outlined.

Supply chain model in a multi-echelon system with inflationary implications

NARCIS (Netherlands)

Jain, R.; Singh, S.R.

2010-01-01

The present study, formulates a multi-echelon supply chain network with a single producer, multi-distributors and multi-retailers for a deteriorating inventory during a finite planning horizon. The inventory levels of the producer and the distributors are assumed to be decreasing by discrete amounts

An Interactive Tool for Creating Multi-Agent Systems and Interactive Agent-based Games

DEFF Research Database (Denmark)

Lund, Henrik Hautop; Pagliarini, Luigi

2011-01-01

Utilizing principles from parallel and distributed processing combined with inspiration from modular robotics, we developed the modular interactive tiles. As an educational tool, the modular interactive tiles facilitate the learning of multi-agent systems and interactive agent-based games...

Interaction Admittance Based Modeling of Multi-Paralleled Grid-Connected Inverter with LCL-Filter

DEFF Research Database (Denmark)

Lu, Minghui; Blaabjerg, Frede; Wang, Xiongfei

2016-01-01

This paper investigates the mutual interaction and stability issues of multi-parallel LCL-filtered inverters. The stability and power quality of multiple grid-tied inverters are gaining more and more research attention as the penetration of renewables increases. In this paper, interactions...... and coupling effects among the multi-paralleled inverters and power grid are explicitly revealed. An Interaction Admittance concept is introduced to express and model the interaction through the physical admittances of the network. Compared to the existing modeling methods, the proposed analysis provides...

A crawling robot driven by multi-stable origami

Science.gov (United States)

Pagano, Alexander; Yan, Tongxi; Chien, Brian; Wissa, A.; Tawfick, S.

2017-09-01

Using origami folding to construct and actuate mechanisms and machines offers attractive opportunities from small, scalable, and cheap robots to deployable adaptive structures. This paper presents the design of a bio-inspired origami crawling robot constructed by folding sheets of paper. The origami building block structure is based on the Kresling crease pattern (CP), a chiral tower with a polygonal base, which expands and contracts through coupled longitudinal and rotational motion similar to a screw. We design the origami to have multi-stable structural equilibria which can be tuned by changing the folding CP. Kinematic analysis of these structures based on rigid-plates and hinges at fold lines precludes the shape transformation associated with the bistability of the physical models. To capture the kinematics of the bi-stable origami, the panels’ deformation behavior is modeled utilizing principles of virtual folds. Virtual folds approximate material bending by hinged, rigid panels, which facilitates the development of a kinematic solution via rigid-plate rotation analysis. As such, the kinetics and stability of folded structures are investigated by assigning suitable torsional spring constants to the fold lines. The results presented demonstrate the effect of fold-pattern geometries on the snapping behavior of the bi-stable origami structure based on the Kresling pattern. The crawling robot is presented as a case study for the use of this origami structure to mimic crawling locomotion. The robot is comprised of two origami towers nested inside a paper bellow, and connected by 3D printed end plates. DC motors are used to actuate the expansion and contraction of the internal origami structures to achieve forward locomotion and steering. Beyond locomotion, this simple design can find applications in manipulators, booms, and active structures.

Artificial emotion triggered stochastic behavior transitions with motivational gain effects for multi-objective robot tasks

Science.gov (United States)

Dağlarli, Evren; Temeltaş, Hakan

2007-04-01

This paper presents artificial emotional system based autonomous robot control architecture. Hidden Markov model developed as mathematical background for stochastic emotional and behavior transitions. Motivation module of architecture considered as behavioral gain effect generator for achieving multi-objective robot tasks. According to emotional and behavioral state transition probabilities, artificial emotions determine sequences of behaviors. Also motivational gain effects of proposed architecture can be observed on the executing behaviors during simulation.

Statistical properties of multi-theta polymer chains

Science.gov (United States)

Uehara, Erica; Deguchi, Tetsuo

2018-04-01

We study statistical properties of polymer chains with complex structures whose chemical connectivities are expressed by graphs. The multi-theta curve of m subchains with two branch points connected by them is one of the simplest graphs among those graphs having closed paths, i.e. loops. We denoted it by θm , and for m  =  2 it is given by a ring. We derive analytically the pair distribution function and the scattering function for the θm -shaped polymer chains consisting of m Gaussian random walks of n steps. Surprisingly, it is shown rigorously that the mean-square radius of gyration for the Gaussian θm -shaped polymer chain does not depend on the number m of subchains if each subchain has the same fixed number of steps. For m  =  3 we show the Kratky plot for the theta-shaped polymer chain consisting of hard cylindrical segments by the Monte-Carlo method including reflection at trivalent vertices.

Software protocol design: Communication and control in a multi-task robot machine for ITER vacuum vessel assembly and maintenance

International Nuclear Information System (INIS)

Li, Ming; Wu, Huapeng; Handroos, Heikki; Yang, Guangyou; Wang, Yongbo

2015-01-01

Highlights: • A high-level protocol is proposed for the data inter-transmission. • The protocol design is task-oriented for the robot control in the software system. • The protocol functions as a role of middleware in the software. • The protocol running stand-alone as an independent process in the software provides greater security. • Providing a reference design protocol for the multi-task robot machine in the industry. - Abstract: A specific communication and control protocol for software design of a multi-task robot machine is proposed. In order to fulfill the requirements on the complicated multi machining functions and the high performance motion control, the software design of robot is divided into two main parts accordingly, which consists of the user-oriented HMI part and robot control-oriented real-time control system. The two parts of software are deployed in the different hardware for the consideration of run-time performance, which forms a client–server-control architecture. Therefore a high-level task-oriented protocol is designed for the data inter-communication between the HMI part and the control system part, in which all the transmitting data related to a machining task is divided into three categories: trajectory-oriented data, task control-oriented data and status monitoring-oriented data. The protocol consists of three sub-protocols accordingly – a trajectory protocol, task control protocol and status protocol – which are deployed over the Ethernet and run as independent processes in both the client and server computers. The protocols are able to manage the vast amounts of data streaming due to the multi machining functions in a more efficient way. Since the protocol is functioning in the software as a role of middleware, and providing the data interface standards for the developing groups of two parts of software, it also permits greater focus of both software parts developers on their own requirements-oriented design. By

Software protocol design: Communication and control in a multi-task robot machine for ITER vacuum vessel assembly and maintenance

Energy Technology Data Exchange (ETDEWEB)

Li, Ming, E-mail: ming.li@lut.fi [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland); Wu, Huapeng; Handroos, Heikki [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland); Yang, Guangyou [School of Mechanical Engineering, Hubei University of Technology, Wuhan (China); Wang, Yongbo [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland)

2015-10-15

Highlights: • A high-level protocol is proposed for the data inter-transmission. • The protocol design is task-oriented for the robot control in the software system. • The protocol functions as a role of middleware in the software. • The protocol running stand-alone as an independent process in the software provides greater security. • Providing a reference design protocol for the multi-task robot machine in the industry. - Abstract: A specific communication and control protocol for software design of a multi-task robot machine is proposed. In order to fulfill the requirements on the complicated multi machining functions and the high performance motion control, the software design of robot is divided into two main parts accordingly, which consists of the user-oriented HMI part and robot control-oriented real-time control system. The two parts of software are deployed in the different hardware for the consideration of run-time performance, which forms a client–server-control architecture. Therefore a high-level task-oriented protocol is designed for the data inter-communication between the HMI part and the control system part, in which all the transmitting data related to a machining task is divided into three categories: trajectory-oriented data, task control-oriented data and status monitoring-oriented data. The protocol consists of three sub-protocols accordingly – a trajectory protocol, task control protocol and status protocol – which are deployed over the Ethernet and run as independent processes in both the client and server computers. The protocols are able to manage the vast amounts of data streaming due to the multi machining functions in a more efficient way. Since the protocol is functioning in the software as a role of middleware, and providing the data interface standards for the developing groups of two parts of software, it also permits greater focus of both software parts developers on their own requirements-oriented design. By

A Neuro-Inspired Spike-Based PID Motor Controller for Multi-Motor Robots with Low Cost FPGAs

Directory of Open Access Journals (Sweden)

Anton Civit-Balcells

2012-03-01

Full Text Available In this paper we present a neuro-inspired spike-based close-loop controller written in VHDL and implemented for FPGAs. This controller has been focused on controlling a DC motor speed, but only using spikes for information representation, processing and DC motor driving. It could be applied to other motors with proper driver adaptation. This controller architecture represents one of the latest layers in a Spiking Neural Network (SNN, which implements a bridge between robotics actuators and spike-based processing layers and sensors. The presented control system fuses actuation and sensors information as spikes streams, processing these spikes in hard real-time, implementing a massively parallel information processing system, through specialized spike-based circuits. This spike-based close-loop controller has been implemented into an AER platform, designed in our labs, that allows direct control of DC motors: the AER-Robot. Experimental results evidence the viability of the implementation of spike-based controllers, and hardware synthesis denotes low hardware requirements that allow replicating this controller in a high number of parallel controllers working together to allow a real-time robot control.

FY 1998 Report on research and development project. Research and development of human-cooperative/coexisting robot systems; 1998 nendo ningen kyocho kyozongata robot system kenkyu kaihatsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

This R and D project is aimed at development of the human-cooperative/coexisting robot systems with high safety and reliability, capable of performing complicated works cooperatively and in a coexisting manner with humans in human working and living spaces, in order to help improve safety and efficiency in various industrial areas, improve services and convenience in manufacturing and service areas, and create new industries. The trend surveys cover humanoid robot systems, remote control systems and simulators, and the application surveys cover services for humans, basic humanoids and entertainment communication. The 1998 R and D efforts include research and development, fabrication and surveys for the following themes; (1) fabrication of robot platforms for supporting manual works, (2) development of surrounded visual display systems, (3) development of robot arm manipulation and force displaying systems, (4) development of a dynamic simulator, (5) development of a distributed software platform, (6) researches and development of computation algorithm for kinematic chain dynamics, (7) development of motion teaching system for multi-functional robots, (8) investigation of trends in robotics technology, and (9) researches and surveys of robot application. (NEDO)

Study on the Workspace of a 6-DOF Parallel Topology Robot Related to Binary Link Lengths

Directory of Open Access Journals (Sweden)

Calin-Octavian Miclosina

2016-12-01

Full Text Available The paper presents a study on the workspace of a parallel topology robot with the structure FP3+6•SPS+MP3. The variable parameters are the binary link lengths, from both upper and lower levels, and the driving kinematical joint strokes. The workspace boundary is determined by SolidWorks software simulations. For different binary link lengths, workspace volume is determined and sections through the workspace are presented.

Distributed Robotics Education

DEFF Research Database (Denmark)

Lund, Henrik Hautop; Pagliarini, Luigi

2011-01-01

Distributed robotics takes many forms, for instance, multirobots, modular robots, and self-reconfigurable robots. The understanding and development of such advanced robotic systems demand extensive knowledge in engineering and computer science. In this paper, we describe the concept of a distribu......Distributed robotics takes many forms, for instance, multirobots, modular robots, and self-reconfigurable robots. The understanding and development of such advanced robotic systems demand extensive knowledge in engineering and computer science. In this paper, we describe the concept...... to be changed, related to multirobot control and human-robot interaction control from virtual to physical representation. The proposed system is valuable for bringing a vast number of issues into education – such as parallel programming, distribution, communication protocols, master dependency, connectivity...

Heterogeneous Multi-Robot Cooperation

Science.gov (United States)

1994-02-01

express my heartfelt thanks to my thesis advisor . Rod Brooks. who supported and encouraged me throughout my time at MIT. He provided a good mixture of...group than is possible with individual robots alone. 25 26 CHAPTER 3. ALLIANCE: THE COOPERATIVE ROBO ,ARCHITECTURE’ discuss the implications of these...available, robot teams should take advantage of it; however, I do not want the team to experience total breakdown when communication becomes unavailable

Robotic multi-well planar patch-clamp for native and primary mammalian cells

Science.gov (United States)

Milligan, Carol J; Li, Jing; Sukumar, Piruthivi; Majeed, Yasser; Dallas, Mark L; English, Anne; Emery, Paul; Porter, Karen E; Smith, Andrew M; McFadzean, Ian; Beccano-Kelly, Dayne; Bahnasi, Yahya; Cheong, Alex; Naylor, Jacqueline; Zeng, Fanning; Liu, Xing; Gamper, Nikita; Jiang, Lin-Hua; Pearson, Hugh A; Peers, Chris; Robertson, Brian; Beech, David J

2009-01-01

Multi-well robotic planar patch-clamp has become common in drug development and safety programmes because it enables efficient and systematic testing of compounds against ion channels during voltage-clamp. It has not, however, been adopted significantly in other important areas of ion channel research, where conventional patch-clamp remains the favoured method. Here we show the wider potential of the multi-well approach with the capability for efficient intracellular solution exchange, describing protocols and success rates for recording from a range of native and primary mammalian cells derived from blood vessels, arthritic joints, and the immune and central nervous systems. The protocol involves preparing a suspension of single cells to be dispensed robotically into 4-8 microfluidic chambers each containing a glass chip with a small aperture. Under automated control, giga-seals and whole-cell access are achieved followed by pre-programmed routines of voltage paradigms and fast extracellular or intracellular solution exchange. Recording from 48 chambers usually takes 1-6 hr depending on the experimental design and yields 16-33 cell recordings. PMID:19197268

Parallel Computational Intelligence-Based Multi-Camera Surveillance System

OpenAIRE

Orts-Escolano, Sergio; Garcia-Rodriguez, Jose; Morell, Vicente; Cazorla, Miguel; Azorin-Lopez, Jorge; García-Chamizo, Juan Manuel

2014-01-01

In this work, we present a multi-camera surveillance system based on the use of self-organizing neural networks to represent events on video. The system processes several tasks in parallel using GPUs (graphic processor units). It addresses multiple vision tasks at various levels, such as segmentation, representation or characterization, analysis and monitoring of the movement. These features allow the construction of a robust representation of the environment and interpret the behavior of mob...

Acceleration of stereo-matching on multi-core CPU and GPU

OpenAIRE

Tian, Xu; Cockshott, Paul; Oehler, Susanne

2014-01-01

This paper presents an accelerated version of a\\ud dense stereo-correspondence algorithm for two different parallelism\\ud enabled architectures, multi-core CPU and GPU. The\\ud algorithm is part of the vision system developed for a binocular\\ud robot-head in the context of the CloPeMa 1 research project.\\ud This research project focuses on the conception of a new clothes\\ud folding robot with real-time and high resolution requirements\\ud for the vision system. The performance analysis shows th...

Tracking control of a closed-chain five-bar robot with two degrees of freedom by integration of an approximation-based approach and mechanical design.

Science.gov (United States)

Cheng, Long; Hou, Zeng-Guang; Tan, Min; Zhang, W J

2012-10-01

The trajectory tracking problem of a closed-chain five-bar robot is studied in this paper. Based on an error transformation function and the backstepping technique, an approximation-based tracking algorithm is proposed, which can guarantee the control performance of the robotic system in both the stable and transient phases. In particular, the overshoot, settling time, and final tracking error of the robotic system can be all adjusted by properly setting the parameters in the error transformation function. The radial basis function neural network (RBFNN) is used to compensate the complicated nonlinear terms in the closed-loop dynamics of the robotic system. The approximation error of the RBFNN is only required to be bounded, which simplifies the initial "trail-and-error" configuration of the neural network. Illustrative examples are given to verify the theoretical analysis and illustrate the effectiveness of the proposed algorithm. Finally, it is also shown that the proposed approximation-based controller can be simplified by a smart mechanical design of the closed-chain robot, which demonstrates the promise of the integrated design and control philosophy.

Multi-objective parallel particle swarm optimization for day-ahead Vehicle-to-Grid scheduling

DEFF Research Database (Denmark)

Soares, Joao; Vale, Zita; Canizes, Bruno

2013-01-01

This paper presents a methodology for multi-objective day-ahead energy resource scheduling for smart grids considering intensive use of distributed generation and Vehicle-To-Grid (V2G). The main focus is the application of weighted Pareto to a multi-objective parallel particle swarm approach aiming...... to solve the dual-objective V2G scheduling: minimizing total operation costs and maximizing V2G income. A realistic mathematical formulation, considering the network constraints and V2G charging and discharging efficiencies is presented and parallel computing is applied to the Pareto weights. AC power flow...

A multi-perspective evaluation of a service robot for seniors: the voice of different stakeholders.

Science.gov (United States)

Bedaf, Sandra; Marti, Patrizia; Amirabdollahian, Farshid; de Witte, Luc

2017-07-31

The potential of service robots for seniors is given increasing attention as the ageing population in Western countries will continue to grow as well as the demand for home care. In order to capture the experience of living with a robot at home, a multi-perspective evaluation was conducted. Older adults (n = 10) were invited to execute an actual interaction scenario with the Care-O-bot ® robot in a home-like environment and were questioned about their experiences. Additionally, interviews were conducted with the elderly participants, informal carers (n = 7) and professional caregivers (n = 11). Seniors showed to be more keen to accept the robot than their caregivers and relatives. However, the robot in its current form was found to be too limited and participants wished the robot could perform more complex tasks. In order to be acceptable a future robot should execute these complex tasks based on the personal preferences of the user which would require the robot to be flexible and extremely smart, comparable to the care that is delivered by a human carer. Developing the functional features to perform activities is not the only challenge in robot development that deserves the attention of robot developers. The development of social behaviour and skills should be addressed as well. This is possible adopting a person-centred design approach, which relies on validation activities with actual users in realistic environments, similar to those described in this paper. Implications for rehabilitation Attitude of older adults towards service robots Potential of service robots for older adults.

Design of a Multi Agent Architecture for Robot Soccer. A Case Study

NARCIS (Netherlands)

Poel, Mannes; Seesink, R.A.; Schoute, Albert L.; Dierssen, W.; Kooij, N.

A Multi Agent System (MAS) for the FIRA Mirosot League is presented. This MAS allows a general number of players and is used in the 5 against 5 and 7 against 7 competition. In the MAS there is coach agent and n (the number of robots in the team) player agents. There is a one to one correspondence

A MULTI-CORE PARALLEL MOSAIC ALORITHM FOR MULTI-VIEW UAV IMAGES

Directory of Open Access Journals (Sweden)

X. Pan

2017-09-01

Full Text Available As the spread of the error and accumulation often lead to distortion or failure of image mosaic during the multi-view UAV (Unmanned Aerial Vehicle images stitching. In this paper, to solve the problem we propose a mosaic strategy to construct a mosaic ring and multi-level grouping parallel acceleration as an auxiliary. First, the input images will be divided into several groups, each group in the ring way to stitch. Then, use SIFT for matching, RANSAC to remove the wrong matching points. And then, calculate the perspective transformation matrix. Finally weaken the error by using the adjustment equation. All these steps run between different groups at the same time. By using real UAV images, the experiment results show that this method can effectively reduce the influence of accumulative error, improve the precision of mosaic and reduce the mosaic time by 60 %. The proposed method can be used as one of the effective ways to minimize the accumulative error.

Robotics for nuclear facilities

International Nuclear Information System (INIS)

Abe, Akira; Nakayama, Ryoichi; Kubo, Katsumi

1988-01-01

It is highly desirable that automatic or remotely controlled machines perform inspection and maintenance tasks in nuclear facilities. Toshiba has been working to develop multi-functional robots, with one typical example being a master-slave manipulator for use in reprocessing facilities. At the same time, the company is also working on the development of multi-purpose intelligent robots. One such device, an automatic inspection robot, to be deployed along a monorail, performs inspection by means of image processing technology, while and advanced intelligent maintenance robot is equipped with a special wheel-locomotion mechanism and manipulator and is designed to perform maintenance tasks. (author)

TRUST AND REPUTATION MODEL DESIGN FOR OBJECTS OF MULTI-AGENT ROBOTICS SYSTEMS WITH DECENTRALIZED CONTROL

Directory of Open Access Journals (Sweden)

I. A. Zikratov

2014-03-01

Full Text Available The problem of mechanisms design for protection of multi-agent robotics systems from attacks of robots-saboteurs is considered. Functioning analysis of these systems with decentralized control is carried out. The type of the so-called soft attacks using interception of messages, misinformation formation and transmission to group of robots which are also realizing other actions without identified signs of invasion of robots-saboteurs. Analysis of existing information security models of the system based on the trust level computation, calculated in the process of agents’ interaction is carried out. Information security model is offered in which robots-agents produce the trust levels to each other on the basis of situation analysis emerging on a certain step of iterative algorithm with usage of onboard sensor devices. On the basis of calculated trust levels, recognition of “saboteur” objects in the group of legitimate robots-agents is done. For measure of likeness (adjacency increase for objects from the same category (“saboteur” or “legitimate agent”, calculation algorithm for agents reputation is offered as a measure of public opinion about qualities of this or that agent-subject. Implementation alternatives of the algorithms for detection of saboteurs on the example of the basic algorithm for distribution of purposes in the group of robots are considered.

Deviation from Trajectory Detection in Vision based Robotic Navigation using SURF and Subsequent Restoration by Dynamic Auto Correction Algorithm

Directory of Open Access Journals (Sweden)

Ray Debraj

2015-01-01

Full Text Available Speeded Up Robust Feature (SURF is used to position a robot with respect to an environment and aid in vision-based robotic navigation. During the course of navigation irregularities in the terrain, especially in an outdoor environment may deviate a robot from the track. Another reason for deviation can be unequal speed of the left and right robot wheels. Hence it is essential to detect such deviations and perform corrective operations to bring the robot back to the track. In this paper we propose a novel algorithm that uses image matching using SURF to detect deviation of a robot from the trajectory and subsequent restoration by corrective operations. This algorithm is executed in parallel to positioning and navigation algorithms by distributing tasks among different CPU cores using Open Multi-Processing (OpenMP API.

GTfold: Enabling parallel RNA secondary structure prediction on multi-core desktops

DEFF Research Database (Denmark)

Swenson, M Shel; Anderson, Joshua; Ash, Andrew

2012-01-01

achieved significant improvements in runtime, but their implementations were not portable from niche high-performance computers or easily accessible to most RNA researchers. With the increasing prevalence of multi-core desktop machines, a new parallel prediction program is needed to take full advantage...

Multi-LED parallel transmission for long distance underwater VLC system with one SPAD receiver

Science.gov (United States)

Wang, Chao; Yu, Hong-Yi; Zhu, Yi-Jun; Wang, Tao; Ji, Ya-Wei

2018-03-01

In this paper, a multiple light emitting diode (LED) chips parallel transmission (Multi-LED-PT) scheme for underwater visible light communication system with one photon-counting single photon avalanche diode (SPAD) receiver is proposed. As the lamp always consists of multi-LED chips, the data rate could be improved when we drive these multi-LED chips parallel by using the interleaver-division-multiplexing technique. For each chip, the on-off-keying modulation is used to reduce the influence of clipping. Then a serial successive interference cancellation detection algorithm based on ideal Poisson photon-counting channel by the SPAD is proposed. Finally, compared to the SPAD-based direct current-biased optical orthogonal frequency division multiplexing system, the proposed Multi-LED-PT system could improve the error-rate performance and anti-nonlinearity performance significantly under the effects of absorption, scattering and weak turbulence-induced channel fading together.

Mechatronic Design of a New Humanoid Robot with Hybrid Parallel Actuation

Directory of Open Access Journals (Sweden)

Vítor Santos

2012-10-01

Full Text Available Humanoid robotics is unquestionably a challenging and long-term field of research. Of the numerous and most urgent challenges to tackle, autonomous and efficient locomotion may possibly be the most underdeveloped at present in the research community. Therefore, to pursue studies in relation to autonomy with efficient locomotion, the authors have been developing a new teen-sized humanoid platform with hybrid characteristics. The hybrid nature is clear in the mixed actuation based on common electrical motors and passive actuators attached in parallel to the motors. This paper presents the mechatronic design of the humanoid platform, focusing mainly on the mechanical structure, the design and simulation of the hybrid joints, and the different subsystems implemented. Trying to keep the appropriate human proportions and main degrees of freedom, the developed platform utilizes a distributed control architecture and a rich set of sensing capabilities, both ripe for future development and research.

Design and Dynamics Analysis of a Bio-Inspired Intermittent Hopping Robot for Planetary Surface Exploration

Directory of Open Access Journals (Sweden)

Long Bai

2012-10-01

Full Text Available A small, bio-inspired and minimally actuated intermittent hopping robot for planetary surface exploration is proposed in this paper. The robot uses a combined-geared six-bar linkage/spring mechanism, which has a possible rich trajectory and metamorphic characteristics and, due to this, the robot is able to recharge, lock/release and jump by using just a micro-power motor as the actuator. Since the robotic system has a closed-chain structure and employs underactuated redundant motion, the constrained multi-body dynamics are derived with time-varying driving parameters and ground unilateral constraint both taken into consideration. In addition, the established dynamics equations, mixed of higher order differential and algebraic expressions, are solved by the immediate integration algorithm. A prototype is implemented and experiments are carried out. The results show that the robot, using a micro-power motor as the actuator and solar cells as the power supply, can achieve a biomimetic multi-body hopping stance and a nonlinearly increasing driving force. Typically, the robot can jump a horizontal distance of about 1 m and a vertical height of about 0.3 m, with its trunk and foot moving stably during takeoff. In addition, the computational and experimental results are consistent as regards the hopping performance of the robot, which suggests that the proposed dynamics model and its solution have general applicability to motion prediction and the performance analysis of intermittent hopping robots.

The Creation of a Multi-Human, Multi-Robot Interactive Jam Session

OpenAIRE

Weinberg, Gil; Blosser, Brian; Mallikarjuna, Trishul; Raman, Aparna

2009-01-01

This paper presents an interactive and improvisational jam session, including human players and two robotic musicians. The project was developed in an effort to create novel and inspiring music through human-robot collaboration. The jam session incorporates Shimon, a newly-developed socially-interactive robotic marimba player, and Haile, a perceptual robotic percussionist developed in previous work. The paper gives an overview of the musical perception modules, adaptive improvisation modes an...

Computational cost of isogeometric multi-frontal solvers on parallel distributed memory machines

KAUST Repository

Woźniak, Maciej; Paszyński, Maciej R.; Pardo, D.; Dalcin, Lisandro; Calo, Victor M.

2015-01-01

This paper derives theoretical estimates of the computational cost for isogeometric multi-frontal direct solver executed on parallel distributed memory machines. We show theoretically that for the Cp-1 global continuity of the isogeometric solution

Self-Organized Multi-Camera Network for a Fast and Easy Deployment of Ubiquitous Robots in Unknown Environments

Science.gov (United States)

Canedo-Rodriguez, Adrián; Iglesias, Roberto; Regueiro, Carlos V.; Alvarez-Santos, Victor; Pardo, Xose Manuel

2013-01-01

To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposal. PMID:23271604

Self-organized multi-camera network for a fast and easy deployment of ubiquitous robots in unknown environments.

Science.gov (United States)

Canedo-Rodriguez, Adrián; Iglesias, Roberto; Regueiro, Carlos V; Alvarez-Santos, Victor; Pardo, Xose Manuel

2012-12-27

To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposal.

A study of the LCA based biofuel supply chain multi-objective optimization model with multi-conversion paths in China

International Nuclear Information System (INIS)

Liu, Zhexuan; Qiu, Tong; Chen, Bingzhen

2014-01-01

Highlights: • A LCA based biofuel supply chain model considering 3E criteria was proposed. • The model was used to design a supply chain considering three conversion pathways. • An experimental biofuel supply chain for China was designed. • A Pareto-optimal solution surface of this multi-objective problem was obtained. • The designed supply chain was rather robust to price variation. - Abstract: In this paper we present a life cycle assessment (LCA) based biofuel supply chain model with multi-conversion pathways. This model was formulated as a mixed integer linear programming (MILP) problem which took economic, energy, and environmental criteria (3E) into consideration. The economic objective was measured by the total annual profit. The energy objective was measured by using the average fossil energy input per megajoule (MJ) of biofuel. The environmental objective was measured by greenhouse gas (GHG) emissions per MJ of biofuel. After carefully consideration of the current situation in China, we chose to examine three conversion pathways: bio-ethanol (BE), bio-methanol (BM) and bio-diesel (BD). LCA was integrated to a multi-objective supply chain model by dividing each pathway into several individual parts and analyzing each part. The multi-objective MILP problem was solved using a ε-constraint method by defining the total annual profit as the optimization objective and assigning the average fossil energy input per MJ biofuel and GHG emissions per MJ biofuel as constraints. This model was then used to design an experimental biofuel supply chain for China. A surface of the Pareto optimal solutions was obtained by linear interpolation of the non-inferior solutions. The optimal results included the choice of optimal conversion pathway, biomass type, biomass locations, facility locations, and network topology structure in the biofuel supply chain. Distributed and centralized systems were also factored into our experimental system design. In addition, the

Development and anti-swing control of an automated measurement robot system for multi-stud tensioning machine

International Nuclear Information System (INIS)

Li Haoyuan; Li Meng; Duan Xingguang; Gao Liang; Cui Tengfei; Guo Yanjun

2017-01-01

During nuclear power plant maintenance, the multi-stud tensioning machine is used to perform opening/sealing the cap of the reactor pressure vessel. This process incorporates elongations of 58 studs, whose extension values are monitored in real time by measurement meters. Conventionally, the placements of the meters are performed by human labor, which is time consuming and radioactively hazardous. In this paper, we introduce an automated measurement robot system, consisting of 58 node robots and multiple field bus based distributed control devices, to complete meter placement and data acquisition tasks without human involvement in the hazardous working site. In order to eliminate the swing phenomenon of the wire-driven meter adaptor on the robot distal end, extra-insensitive input shaper is employed for robot motion control, thus saving the overall operation time from traditionally over 10 minutes to less than 22 s. (author)

Navigation control of a multi-functional eye robot

International Nuclear Information System (INIS)

Ali, F.A.M.; Hashmi, B.; Younas, A.; Abid, B.

2016-01-01

The advancement in robotic field is enhanced rigorously in the past Few decades. Robots are being used in different fields of science as well as warfare. The research shows that in the near future, robots would be able to serve in fighting wars. Different countries and their armies have already deployed several military robots. However, there exist some drawbacks of robots like their inefficiency and inability to work under abnormal conditions. Ascent of artificial intelligence may resolve this issue in the coming future. The main focus of this paper is to provide a low cost and long range most efficient mechanical as well as software design of an Eye Robot. Using a blend of robotics and image processing with an addition of artificial intelligence path navigation techniques, this project is designed and implemented by controlling the robot (including robotic arm and camera) through a 2.4 GHz RF module manually. Autonomous function of the robot includes navigation based on the path assigned to the robot. The path is drawn on a VB based application and then transferred to the robot wirelessly or through serial port. A Wi-Fi based Optical Character Recognition (OCR) implemented video streaming can also be observed at remote devices like laptops. (author)

Selective maintenance for multi-state series–parallel systems under economic dependence

International Nuclear Information System (INIS)

Dao, Cuong D.; Zuo, Ming J.; Pandey, Mayank

2014-01-01

This paper presents a study on selective maintenance for multi-state series–parallel systems with economically dependent components. In the selective maintenance problem, the maintenance manager has to decide which components should receive maintenance activities within a finite break between missions. All the system reliabilities in the next operating mission, the available budget and the maintenance time for each component from its current state to a higher state are taken into account in the optimization models. In addition, the components in series–parallel systems are considered to be economically dependent. Time and cost savings will be achieved when several components are simultaneously repaired in a selective maintenance strategy. As the number of repaired components increases, the saved time and cost will also increase due to the share of setting up between components and another additional reduction amount resulting from the repair of multiple identical components. Different optimization models are derived to find the best maintenance strategy for multi-state series–parallel systems. A genetic algorithm is used to solve the optimization models. The decision makers may select different components to be repaired to different working states based on the maintenance objective, resource availabilities and how dependent the repair time and cost of each component are

Design and implementation of wormlike creeping mobile robot for EAST remote maintenance system

Energy Technology Data Exchange (ETDEWEB)

Zhang, Qiang, E-mail: zhangqiang@iim.ac.cn [Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Department of Automation, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhou, Ling [Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Wang, Zengfu, E-mail: zfwang@ustc.edu.cn [Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Department of Automation, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2017-05-15

Highlights: • Wormlike creeping robot walking on the V-shaped circular slot in EAST fusion vessel. • Mobile platform to carry equipments or assist manipulators for maintenance tasks. • Chain structure design with n(n ≥ 2) creeping units each of which has three segments. • Creeping gait planning to construct a multi-axis coordinating control scheme. • Evaluation and verification of basic motion performance and mechanical properties. - Abstract: Maintenance for nuclear fusion vessel is crucial, yet it faces great difficulty due to the complex internal physical and geometric conditions. Since the limitation on inherent strength, load, size, etc, a manipulator robot can only complete very limited tasks. Robotic arm systems for remote operation such as JET and MPD can carry certain tools to complete a variety of operating tasks, but it is difficult to achieve the system which is very complex. Therefore, if the inherent idea of using a single robot to complete the specified functions can change, it is possible to make the problems simpler and easier to solve by adding auxiliary robots working together with the robotic arm systems to complete the assigned tasks. Under the above background, based on the deeply analyzing and refining the functional requirements of the vessel operation robot, proceeding from the perspective of ability to move and carry a certain operating device, this paper presents a wormlike creeping mobile robot walking on the V-shaped circular slot inside a nuclear fusion vessel such as EAST (Experimental Advanced Superconducting Tokamak). We have designed and implemented the principle prototype of the robot which has chain structure with n (n ≥2) creeping units. Each creeping unit is of three-part structure, which consists of fore segment, mid segment and back segment connected by bidirectional universal joint. The fore and back segments stretch the paws to contact the surface of V-shaped slot, while the mid segment realizes the overall

Design and implementation of wormlike creeping mobile robot for EAST remote maintenance system

International Nuclear Information System (INIS)

Zhang, Qiang; Zhou, Ling; Wang, Zengfu

2017-01-01

Highlights: • Wormlike creeping robot walking on the V-shaped circular slot in EAST fusion vessel. • Mobile platform to carry equipments or assist manipulators for maintenance tasks. • Chain structure design with n(n ≥ 2) creeping units each of which has three segments. • Creeping gait planning to construct a multi-axis coordinating control scheme. • Evaluation and verification of basic motion performance and mechanical properties. - Abstract: Maintenance for nuclear fusion vessel is crucial, yet it faces great difficulty due to the complex internal physical and geometric conditions. Since the limitation on inherent strength, load, size, etc, a manipulator robot can only complete very limited tasks. Robotic arm systems for remote operation such as JET and MPD can carry certain tools to complete a variety of operating tasks, but it is difficult to achieve the system which is very complex. Therefore, if the inherent idea of using a single robot to complete the specified functions can change, it is possible to make the problems simpler and easier to solve by adding auxiliary robots working together with the robotic arm systems to complete the assigned tasks. Under the above background, based on the deeply analyzing and refining the functional requirements of the vessel operation robot, proceeding from the perspective of ability to move and carry a certain operating device, this paper presents a wormlike creeping mobile robot walking on the V-shaped circular slot inside a nuclear fusion vessel such as EAST (Experimental Advanced Superconducting Tokamak). We have designed and implemented the principle prototype of the robot which has chain structure with n (n ≥2) creeping units. Each creeping unit is of three-part structure, which consists of fore segment, mid segment and back segment connected by bidirectional universal joint. The fore and back segments stretch the paws to contact the surface of V-shaped slot, while the mid segment realizes the overall

A Formal Model of Trust Chain based on Multi-level Security Policy

OpenAIRE

Kong Xiangying

2013-01-01

Trust chain is the core technology of trusted computing. A formal model of trust chain based on finite state automata theory is proposed. We use communicating sequential processes to describe the system state transition in trust chain and by combining with multi-level security strategy give the definition of trust system and trust decision theorem of trust chain transfer which is proved meantime. Finally, a prototype system is given to show the efficiency of the model.

A multi-objective optimization problem for multi-state series-parallel systems: A two-stage flow-shop manufacturing system

International Nuclear Information System (INIS)

Azadeh, A.; Maleki Shoja, B.; Ghanei, S.; Sheikhalishahi, M.

2015-01-01

This research investigates a redundancy-scheduling optimization problem for a multi-state series parallel system. The system is a flow shop manufacturing system with multi-state machines. Each manufacturing machine may have different performance rates including perfect performance, decreased performance and complete failure. Moreover, warm standby redundancy is considered for the redundancy allocation problem. Three objectives are considered for the problem: (1) minimizing system purchasing cost, (2) minimizing makespan, and (3) maximizing system reliability. Universal generating function is employed to evaluate system performance and overall reliability of the system. Since the problem is in the NP-hard class of combinatorial problems, genetic algorithm (GA) is used to find optimal/near optimal solutions. Different test problems are generated to evaluate the effectiveness and efficiency of proposed approach and compared to simulated annealing optimization method. The results show the proposed approach is capable of finding optimal/near optimal solution within a very reasonable time. - Highlights: • A redundancy-scheduling optimization problem for a multi-state series parallel system. • A flow shop with multi-state machines and warm standby redundancy. • Objectives are to optimize system purchasing cost, makespan and reliability. • Different test problems are generated and evaluated by a unique genetic algorithm. • It locates optimal/near optimal solution within a very reasonable time

Multi-GPU parallel algorithm design and analysis for improved inversion of probability tomography with gravity gradiometry data

Science.gov (United States)

Hou, Zhenlong; Huang, Danian

2017-09-01

In this paper, we make a study on the inversion of probability tomography (IPT) with gravity gradiometry data at first. The space resolution of the results is improved by multi-tensor joint inversion, depth weighting matrix and the other methods. Aiming at solving the problems brought by the big data in the exploration, we present the parallel algorithm and the performance analysis combining Compute Unified Device Architecture (CUDA) with Open Multi-Processing (OpenMP) based on Graphics Processing Unit (GPU) accelerating. In the test of the synthetic model and real data from Vinton Dome, we get the improved results. It is also proved that the improved inversion algorithm is effective and feasible. The performance of parallel algorithm we designed is better than the other ones with CUDA. The maximum speedup could be more than 200. In the performance analysis, multi-GPU speedup and multi-GPU efficiency are applied to analyze the scalability of the multi-GPU programs. The designed parallel algorithm is demonstrated to be able to process larger scale of data and the new analysis method is practical.

Multi states electromechanical switch for energy efficient parallel data processing

KAUST Repository

Kloub, Hussam; Smith, Casey; Hussain, Muhammad Mustafa

2011-01-01

We present a design, simulation results and fabrication of electromechanical switches enabling parallel data processing and multi functionality. The device is applied in logic gates AND, NOR, XNOR, and Flip-Flops. The device footprint size is 2μm by 0.5μm, and has a pull-in voltage of 5.15V which is verified by FEM simulation. © 2011 IEEE.

Multi states electromechanical switch for energy efficient parallel data processing

KAUST Repository

Kloub, Hussam

2011-04-01

We present a design, simulation results and fabrication of electromechanical switches enabling parallel data processing and multi functionality. The device is applied in logic gates AND, NOR, XNOR, and Flip-Flops. The device footprint size is 2μm by 0.5μm, and has a pull-in voltage of 5.15V which is verified by FEM simulation. © 2011 IEEE.

A new macro-micro dual drive parallel robot for chromosome dissection

Energy Technology Data Exchange (ETDEWEB)

Feng, Jin; Gao, Feng; Zhao, Xianchao; Yue, Yi; Liu, Renqiang [Shanghai Jiao Tong University, Shanghai (China)

2012-01-15

This paper presents a parallel-structure system dually driven by six servo motors and six piezoelectric actuators. Due to the combination of macro and micro manipulators which are both of orthogonal structures, the proposed system possesses a concise structure as well as actuation isolation and output motion decoupling properties. By using a glass needle mounted on a six-dimensional force sensor in endpoint operating, this system can be applied to chromosome dissection that to make the whole process more efficient and automatic. The glass needle tip has a stroke of 106 mm in three linear motions and 18.7-arc-degrees in three angle motion directions, with servo motors adopted. It also has the resolution of 20 nanometers with the adoption of piezoelectric actuators. The kinematics, isotropy, decoupling and design considerations of the proposed robot are discussed. Workspace and resolution of both macro and micro manipulators are measured separately. The experiments are also conducted to show its capability in dissecting chromosomes.

Effects of Assist-As-Needed Upper Extremity Robotic Therapy after Incomplete Spinal Cord Injury: A Parallel-Group Controlled Trial

Directory of Open Access Journals (Sweden)

John Michael Frullo

2017-06-01

Full Text Available BackgroundRobotic rehabilitation of the upper limb following neurological injury has been supported through several large clinical studies for individuals with chronic stroke. The application of robotic rehabilitation to the treatment of other neurological injuries is less developed, despite indications that strategies successful for restoration of motor capability following stroke may benefit individuals with incomplete spinal cord injury (SCI as well. Although recent studies suggest that robot-aided rehabilitation might be beneficial after incomplete SCI, it is still unclear what type of robot-aided intervention contributes to motor recovery.MethodsWe developed a novel assist-as-needed (AAN robotic controller to adjust challenge and robotic assistance continuously during rehabilitation therapy delivered via an upper extremity exoskeleton, the MAHI Exo-II, to train independent elbow and wrist joint movements. We further enrolled seventeen patients with incomplete spinal cord injury (AIS C and D levels in a parallel-group balanced controlled trial to test the efficacy of the AAN controller, compared to a subject-triggered (ST controller that does not adjust assistance or challenge levels continuously during therapy. The conducted study is a stage two, development-of-concept pilot study.ResultsWe validated the AAN controller in its capability of modulating assistance and challenge during therapy via analysis of longitudinal robotic metrics. For the selected primary outcome measure, the pre–post difference in ARAT score, no statistically significant change was measured in either group of subjects. Ancillary analysis of secondary outcome measures obtained via robotic testing indicates gradual improvement in movement quality during the therapy program in both groups, with the AAN controller affording greater increases in movement quality over the ST controller.ConclusionThe present study demonstrates feasibility of subject-adaptive robotic therapy

Joint redundancy and imperfect preventive maintenance optimization for series–parallel multi-state degraded systems

International Nuclear Information System (INIS)

Nourelfath, Mustapha; Châtelet, Eric; Nahas, Nabil

2012-01-01

This paper formulates a joint redundancy and imperfect preventive maintenance planning optimization model for series–parallel multi-state degraded systems. Non identical multi-state components can be used in parallel to improve the system availability by providing redundancy in subsystems. Multiple component choices are available in the market for each subsystem. The status of each component is considered to degrade with use. The objective is to determine jointly the maximal-availability series–parallel system structure and the appropriate preventive maintenance actions, subject to a budget constraint. System availability is defined as the ability to satisfy consumer demand that is represented as a piecewise cumulative load curve. A procedure is used, based on Markov processes and universal moment generating function, to evaluate the multi-state system availability and the cost function. A heuristic approach is also proposed to solve the formulated problem. This heuristic is based on a combination of space partitioning, genetic algorithms (GA) and tabu search (TS). After dividing the search space into a set of disjoint subsets, this approach uses GA to select the subspaces, and applies TS to each selected sub-space.

An Integer Programming Model for Multi-Echelon Supply Chain Decision Problem Considering Inventories

Science.gov (United States)

Harahap, Amin; Mawengkang, Herman; Siswadi; Effendi, Syahril

2018-01-01

In this paper we address a problem that is of significance to the industry, namely the optimal decision of a multi-echelon supply chain and the associated inventory systems. By using the guaranteed service approach to model the multi-echelon inventory system, we develop a mixed integer; programming model to simultaneously optimize the transportation, inventory and network structure of a multi-echelon supply chain. To solve the model we develop a direct search approach using a strategy of releasing nonbasic variables from their bounds, combined with the “active constraint” method. This strategy is used to force the appropriate non-integer basic variables to move to their neighbourhood integer points.

A Multi-Armed Bandit Approach to Following a Markov Chain

Science.gov (United States)

2017-06-01

Introduction to online convex optimization ,” Foundations and Trends in Optimization , vol. 2, no. 3-4, pp. 157–325, 2016. [3] A. Mahajan and D. Teneketzis...stochastic optimization , machine learning, discrete time Markov chains, stochastic Multi-Armed Bandit, combinatorial Multi-Armed Bandit, online learning, and...fulfillment of the requirements for the degree of MASTER OF SCIENCE IN OPERATIONS RESEARCH from the NAVAL POSTGRADUATE SCHOOL June 2017 Approved by: Roberto

Massively Parallel Sort-Merge Joins in Main Memory Multi-Core Database Systems

OpenAIRE

Albutiu, Martina-Cezara; Kemper, Alfons; Neumann, Thomas

2012-01-01

Two emerging hardware trends will dominate the database system technology in the near future: increasing main memory capacities of several TB per server and massively parallel multi-core processing. Many algorithmic and control techniques in current database technology were devised for disk-based systems where I/O dominated the performance. In this work we take a new look at the well-known sort-merge join which, so far, has not been in the focus of research in scalable massively parallel mult...

A Novel Reconfiguration Strategy of a Delta-Type Parallel Manipulator

Directory of Open Access Journals (Sweden)

Albert Lester Balmaceda-Santamaría

2016-02-01

Full Text Available This work introduces a novel reconfiguration strategy for a Delta-type parallel robot. The robot at hand, whose patent is pending, is equipped with an intermediate mechanism that allows for modifying the operational Cartesian workspace. Furthermore, singularities of the robot may be ameliorated owing to the inherent kinematic redundancy introduced by four actuable kinematic joints. The velocity and acceleration analyses of the parallel manipulator are carried out by resorting to reciprocal-screw theory. Finally, the manipulability of the new robot is investigated based on the computation of the condition number associated with the active Jacobian matrix, a well-known procedure. The results obtained show improved performance of the robot introduced when compared with results generated for another Delta-type robot.

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

Directory of Open Access Journals (Sweden)

Pingxia Zhang

2016-05-01

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

Parallel manipulators with two end-effectors : Getting a grip on Jacobian-based stiffness analysis

NARCIS (Netherlands)

Hoevenaars, A.G.L.

2016-01-01

Robots that are developed for applications which require a high stiffness-over-inertia ratio, such as pick-and-place robots, machining robots, or haptic devices, are often based on parallel manipulators. Parallel manipulators connect an end-effector to an inertial base using multiple serial

Robotic inspection of fiber reinforced composites using phased array UT

Science.gov (United States)

Stetson, Jeffrey T.; De Odorico, Walter

2014-02-01

Ultrasound is the current NDE method of choice to inspect large fiber reinforced airframe structures. Over the last 15 years Cartesian based scanning machines using conventional ultrasound techniques have been employed by all airframe OEMs and their top tier suppliers to perform these inspections. Technical advances in both computing power and commercially available, multi-axis robots now facilitate a new generation of scanning machines. These machines use multiple end effector tools taking full advantage of phased array ultrasound technologies yielding substantial improvements in inspection quality and productivity. This paper outlines the general architecture for these new robotic scanning systems as well as details the variety of ultrasonic techniques available for use with them including advances such as wide area phased array scanning and sound field adaptation for non-flat, non-parallel surfaces.

Multi-fingered robotic hand

Science.gov (United States)

Ruoff, Carl F. (Inventor); Salisbury, Kenneth, Jr. (Inventor)

1990-01-01

A robotic hand is presented having a plurality of fingers, each having a plurality of joints pivotally connected one to the other. Actuators are connected at one end to an actuating and control mechanism mounted remotely from the hand and at the other end to the joints of the fingers for manipulating the fingers and passing externally of the robot manipulating arm in between the hand and the actuating and control mechanism. The fingers include pulleys to route the actuators within the fingers. Cable tension sensing structure mounted on a portion of the hand are disclosed, as is covering of the tip of each finger with a resilient and pliable friction enhancing surface.

MÓDULO CONDUCTUAL INMERSO EN UNA ARQUITECTURA DE CONTROL PARA SISTEMAS MULTI-ROBOTS

Directory of Open Access Journals (Sweden)

Ángel Eduardo Gil Pérez

2016-03-01

Full Text Available El presente trabajo describe el diseño de un módulo conductual para robots de propósito general, implementado en el marco de una arquitectura de control para sistemas multi-robots.El mismo está estructurado en cuatro capas: reactiva, cognitiva, social, y una capa transversal que gestiona un conjunto de emociones básicas, que afectan de forma directael comportamiento del robot y su disposición hacia la ejecución de las tareas y hacia la interrelación con los otros individuos del sistema (es decir, a las otras capas. El objetivo de la arquitectura es brindar una plataforma que facilite los procesos de auto-organización y emergencia del sistema.Se propone un modelo emocional, que toma en consideración cuatro emociones básicas y un estado neutro; esto con el fin de dotar a los robots de un factor adicional que influya en su funcionamiento, que puede ser determinante cuando estos enfrentan situaciones donde la incertidumbre se hace presente. De esta forma, se busca mejorar su proceso de toma de decisión y su adaptación a las dinámicas presentes en el entorno, en particular analizando la influencia de las emociones en sistemas de este tipo.

Static stiffness modeling of a novel hybrid redundant robot machine

International Nuclear Information System (INIS)

Li Ming; Wu Huapeng; Handroos, Heikki

2011-01-01

This paper presents a modeling method to study the stiffness of a hybrid serial-parallel robot IWR (Intersector Welding Robot) for the assembly of ITER vacuum vessel. The stiffness matrix of the basic element in the robot is evaluated using matrix structural analysis (MSA); the stiffness of the parallel mechanism is investigated by taking account of the deformations of both hydraulic limbs and joints; the stiffness of the whole integrated robot is evaluated by employing the virtual joint method and the principle of virtual work. The obtained stiffness model of the hybrid robot is analytical and the deformation results of the robot workspace under certain external load are presented.

Introduction to humanoid robotics

CERN Document Server

Kajita, Shuuji; Harada, Kensuke; Yokoi, Kazuhito

2014-01-01

This book is for researchers, engineers, and students who are willing to understand how humanoid robots move and be controlled. The book starts with an overview of the humanoid robotics research history and state of the art. Then it explains the required mathematics and physics such as kinematics of multi-body system, Zero-Moment Point (ZMP) and its relationship with body motion. Biped walking control is discussed in depth, since it is one of the main interests of humanoid robotics. Various topics of the whole body motion generation are also discussed. Finally multi-body dynamics is presented to simulate the complete dynamic behavior of a humanoid robot. Throughout the book, Matlab codes are shown to test the algorithms and to help the reader´s understanding.

Robots and lattice automata

CERN Document Server

Adamatzky, Andrew

2015-01-01

The book gives a comprehensive overview of the state-of-the-art research and engineering in theory and application of Lattice Automata in design and control of autonomous Robots. Automata and robots share the same notional meaning. Automata (originated from the latinization of the Greek word “αυτόματον”) as self-operating autonomous machines invented from ancient years can be easily considered the first steps of robotic-like efforts. Automata are mathematical models of Robots and also they are integral parts of robotic control systems. A Lattice Automaton is a regular array or a collective of finite state machines, or automata. The Automata update their states by the same rules depending on states of their immediate neighbours. In the context of this book, Lattice Automata are used in developing modular reconfigurable robotic systems, path planning and map exploration for robots, as robot controllers, synchronisation of robot collectives, robot vision, parallel robotic actuators. All chapters are...

A Method for Improving the Pose Accuracy of a Robot Manipulator Based on Multi-Sensor Combined Measurement and Data Fusion

Science.gov (United States)

Liu, Bailing; Zhang, Fumin; Qu, Xinghua

2015-01-01

An improvement method for the pose accuracy of a robot manipulator by using a multiple-sensor combination measuring system (MCMS) is presented. It is composed of a visual sensor, an angle sensor and a series robot. The visual sensor is utilized to measure the position of the manipulator in real time, and the angle sensor is rigidly attached to the manipulator to obtain its orientation. Due to the higher accuracy of the multi-sensor, two efficient data fusion approaches, the Kalman filter (KF) and multi-sensor optimal information fusion algorithm (MOIFA), are used to fuse the position and orientation of the manipulator. The simulation and experimental results show that the pose accuracy of the robot manipulator is improved dramatically by 38%∼78% with the multi-sensor data fusion. Comparing with reported pose accuracy improvement methods, the primary advantage of this method is that it does not require the complex solution of the kinematics parameter equations, increase of the motion constraints and the complicated procedures of the traditional vision-based methods. It makes the robot processing more autonomous and accurate. To improve the reliability and accuracy of the pose measurements of MCMS, the visual sensor repeatability is experimentally studied. An optimal range of 1 × 0.8 × 1 ∼ 2 × 0.8 × 1 m in the field of view (FOV) is indicated by the experimental results. PMID:25850067

Mathematical Methods and Algorithms of Mobile Parallel Computing on the Base of Multi-core Processors

Directory of Open Access Journals (Sweden)

Alexander B. Bakulev

2012-11-01

Full Text Available This article deals with mathematical models and algorithms, providing mobility of sequential programs parallel representation on the high-level language, presents formal model of operation environment processes management, based on the proposed model of programs parallel representation, presenting computation process on the base of multi-core processors.

Stepwise multi-criteria optimization for robotic radiosurgery

International Nuclear Information System (INIS)

Schlaefer, A.; Schweikard, A.

2008-01-01

Achieving good conformality and a steep dose gradient around the target volume remains a key aspect of radiosurgery. Clearly, this involves a trade-off between target coverage, conformality of the dose distribution, and sparing of critical structures. Yet, image guidance and robotic beam placement have extended highly conformal dose delivery to extracranial and moving targets. Therefore, the multi-criteria nature of the optimization problem becomes even more apparent, as multiple conflicting clinical goals need to be considered coordinate to obtain an optimal treatment plan. Typically, planning for robotic radiosurgery is based on constrained optimization, namely linear programming. An extension of that approach is presented, such that each of the clinical goals can be addressed separately and in any sequential order. For a set of common clinical goals the mapping to a mathematical objective and a corresponding constraint is defined. The trade-off among the clinical goals is explored by modifying the constraints and optimizing a simple objective, while retaining feasibility of the solution. Moreover, it becomes immediately obvious whether a desired goal can be achieved and where a trade-off is possible. No importance factors or predefined prioritizations of clinical goals are necessary. The presented framework forms the basis for interactive and automated planning procedures. It is demonstrated for a sample case that the linear programming formulation is suitable to search for a clinically optimal treatment, and that the optimization steps can be performed quickly to establish that a Pareto-efficient solution has been found. Furthermore, it is demonstrated how the stepwise approach is preferable compared to modifying importance factors

Advances in robot kinematics

CERN Document Server

Khatib, Oussama

2014-01-01

The topics addressed in this book cover the whole range of kinematic analysis, synthesis and design and consider robotic systems possessing serial, parallel and cable driven mechanisms. The robotic systems range from being less than fully mobile to kinematically redundant to overconstrained.  The fifty-six contributions report the latest results in robot kinematics with emphasis on emerging areas such as design and control of humanoids or humanoid subsystems. The book is of interest to researchers wanting to bring their knowledge up to date regarding modern topics in one of the basic disciplines in robotics, which relates to the essential property of robots, the motion of mechanisms.

R and D on robots for nuclear power plants in 'advanced robot technology' project

International Nuclear Information System (INIS)

Ando, Hiroaki

1987-01-01

The project aims at developing a safe man-robot system of high mobility and workability, highly adaptable to the working environment, and readily and reliably remote-controlled. The plan is to develop 'multi-purpose robots' that can do monitoring, inspection and light work quickly and correctly in areas where access of humans is difficult (e.g. hot spots and the inner space of the primary containment vessel), and 'robots used exclusively for valves, pumps, and other equipment, multi-functional to be used only for specific purposes'. This can be expected to be completed on the basis of results in research and development for the multi-purpose robots. R and D on the total system means manufacturing an optimum system with sufficient functions and performance required for the robot by combining existing technologies most adequately on the basis of the results of research and development on the project. After conceptual drawing and conceptual design, the system will be manufactured and demonstration tests will be completed by fiscal 1987 or 1988. This report describes the total image of the robots concerning the shape, locomotion, manipulation, perception, communication, control management, reliability and environmental durability, and then outlines the research and development activities regarding locomotion, manipulator, tectile sensor, actuator, single-eye three-dimensional measurement, visual data processing, optical spacial transmission, failure repair controller, functional reduction, robot health care and radiation resistance. (Nogami, K.)

Solving the Selective Multi-Category Parallel-Servicing Problem

DEFF Research Database (Denmark)

Range, Troels Martin; Lusby, Richard Martin; Larsen, Jesper

In this paper we present a new scheduling problem and describe a shortest path based heuristic as well as a dynamic programming based exact optimization algorithm to solve it. The Selective Multi-Category Parallel-Servicing Problem (SMCPSP) arises when a set of jobs has to be scheduled on a server...... (machine) with limited capacity. Each job requests service in a prespecified time window and belongs to a certain category. Jobs may be serviced partially, incurring a penalty; however, only jobs of the same category can be processed simultaneously. One must identify the best subset of jobs to process...

Solving the selective multi-category parallel-servicing problem

DEFF Research Database (Denmark)

Range, Troels Martin; Lusby, Richard Martin; Larsen, Jesper

2015-01-01

In this paper, we present a new scheduling problem and describe a shortest path-based heuristic as well as a dynamic programming-based exact optimization algorithm to solve it. The selective multi-category parallel-servicing problem arises when a set of jobs has to be scheduled on a server (machine......) with limited capacity. Each job requests service in a prespecified time window and belongs to a certain category. Jobs may be serviced partially, incurring a penalty; however, only jobs of the same category can be processed simultaneously. One must identify the best subset of jobs to process in each time...

Modelling cooperation of industrial robots as multi-agent systems

Science.gov (United States)

Hryniewicz, P.; Banas, W.; Foit, K.; Gwiazda, A.; Sekala, A.

2017-08-01

Nowadays, more and more often in a cell is more than one robot, there is also a dual arm robots, because of this cooperation of two robots in the same space becomes more and more important. Programming robotic cell consisting of two or more robots are currently performed separately for each element of the robot and the cell. It is performed only synchronization programs, but no robot movements. In such situations often placed industrial robots so they do not have common space so the robots are operated separately. When industrial robots are a common space this space can occupy only one robot the other one must be outside the common space. It is very difficult to find applications where two robots are in the same workspace. It was tested but one robot did not do of movement when moving the second and waited for permission to move from the second when it sent a permit - stop the move. Such programs are very difficult and require a lot of experience from the programmer and must be tested separately at the beginning and then very slowly under control. Ideally, the operator takes care of exactly one robot during the test and it is very important to take special care.

Adaptive Load Balancing of Parallel Applications with Multi-Agent Reinforcement Learning on Heterogeneous Systems

Directory of Open Access Journals (Sweden)

Johan Parent

2004-01-01

Full Text Available We report on the improvements that can be achieved by applying machine learning techniques, in particular reinforcement learning, for the dynamic load balancing of parallel applications. The applications being considered in this paper are coarse grain data intensive applications. Such applications put high pressure on the interconnect of the hardware. Synchronization and load balancing in complex, heterogeneous networks need fast, flexible, adaptive load balancing algorithms. Viewing a parallel application as a one-state coordination game in the framework of multi-agent reinforcement learning, and by using a recently introduced multi-agent exploration technique, we are able to improve upon the classic job farming approach. The improvements are achieved with limited computation and communication overhead.

Hand-held multi-DOF robotic forceps for neurosurgery designed for dexterous manipulation in deep and narrow space.

Science.gov (United States)

Okubo, Takuro; Harada, Kanako; Fujii, Masahiro; Tanaka, Shinichi; Ishimaru, Tetsuya; Iwanaka, Tadashi; Nakatomi, Hirohumi; Sora, Sigeo; Morita, Akio; Sugita, Naohiko; Mitsuishi, Mamoru

2014-01-01

Neurosurgical procedures require precise and dexterous manipulation of a surgical suture in narrow and deep spaces in the brain. This is necessary for surgical tasks such as the anastomosis of microscopic blood vessels and dura mater suturing. A hand-held multi-degree of freedom (DOF) robotic forceps was developed to aid the performance of such difficult tasks. The diameter of the developed robotic forceps is 3.5 mm, and its tip has three DOFs, namely, bending, rotation, and grip. Experimental results showed that the robotic forceps had an average needle insertion force of 1.7 N. Therefore, an increase in the needle insertion force is necessary for practical application of the developed device.

Analytic hierarchy process-based approach for selecting a Pareto-optimal solution of a multi-objective, multi-site supply-chain planning problem

Science.gov (United States)

Ayadi, Omar; Felfel, Houssem; Masmoudi, Faouzi

2017-07-01

The current manufacturing environment has changed from traditional single-plant to multi-site supply chain where multiple plants are serving customer demands. In this article, a tactical multi-objective, multi-period, multi-product, multi-site supply-chain planning problem is proposed. A corresponding optimization model aiming to simultaneously minimize the total cost, maximize product quality and maximize the customer satisfaction demand level is developed. The proposed solution approach yields to a front of Pareto-optimal solutions that represents the trade-offs among the different objectives. Subsequently, the analytic hierarchy process method is applied to select the best Pareto-optimal solution according to the preferences of the decision maker. The robustness of the solutions and the proposed approach are discussed based on a sensitivity analysis and an application to a real case from the textile and apparel industry.

Dynamic Analysis of Planar 3-RRR Flexible Parallel Robots with Dynamic Stiffening

Directory of Open Access Journals (Sweden)

Qinghua Zhang

2014-01-01

Full Text Available In consideration of the second-order coupling quantity of the axial displacement caused by the transverse displacement of flexible beam, the first-order approximation coupling model of planar 3-RRR flexible parallel robots is presented, in which the rigid body motion constraints, elastic deformation motion constraints, and dynamic constraints of the moving platform are considered. Based on the different speed of the moving platform, numerical simulation results using the conventional zero-order approximation coupling model and the proposed firstorder approximation coupling model show that the effect of “dynamic stiffening” term on dynamic characteristics of the system is insignificant and can be neglected, and the zero-order approximation coupling model is enough precisely for catching essentially dynamic characteristics of the system. Then, the commercial software ANSYS 13.0 is used to confirm the validity of the zero-order approximation coupling model.

Bayesian inversion of seismic and electromagnetic data for marine gas reservoir characterization using multi-chain Markov chain Monte Carlo sampling

International Nuclear Information System (INIS)

Ren, Huiying; Ray, Jaideep; Hou, Zhangshuan; Huang, Maoyi; Bao, Jie; Swiler, Laura

2017-01-01

In this paper we developed an efficient Bayesian inversion framework for interpreting marine seismic Amplitude Versus Angle and Controlled-Source Electromagnetic data for marine reservoir characterization. The framework uses a multi-chain Markov-chain Monte Carlo sampler, which is a hybrid of DiffeRential Evolution Adaptive Metropolis and Adaptive Metropolis samplers. The inversion framework is tested by estimating reservoir-fluid saturations and porosity based on marine seismic and Controlled-Source Electromagnetic data. The multi-chain Markov-chain Monte Carlo is scalable in terms of the number of chains, and is useful for computationally demanding Bayesian model calibration in scientific and engineering problems. As a demonstration, the approach is used to efficiently and accurately estimate the porosity and saturations in a representative layered synthetic reservoir. The results indicate that the seismic Amplitude Versus Angle and Controlled-Source Electromagnetic joint inversion provides better estimation of reservoir saturations than the seismic Amplitude Versus Angle only inversion, especially for the parameters in deep layers. The performance of the inversion approach for various levels of noise in observational data was evaluated — reasonable estimates can be obtained with noise levels up to 25%. Sampling efficiency due to the use of multiple chains was also checked and was found to have almost linear scalability.

Bayesian inversion of seismic and electromagnetic data for marine gas reservoir characterization using multi-chain Markov chain Monte Carlo sampling

Science.gov (United States)

Ren, Huiying; Ray, Jaideep; Hou, Zhangshuan; Huang, Maoyi; Bao, Jie; Swiler, Laura

2017-12-01

In this study we developed an efficient Bayesian inversion framework for interpreting marine seismic Amplitude Versus Angle and Controlled-Source Electromagnetic data for marine reservoir characterization. The framework uses a multi-chain Markov-chain Monte Carlo sampler, which is a hybrid of DiffeRential Evolution Adaptive Metropolis and Adaptive Metropolis samplers. The inversion framework is tested by estimating reservoir-fluid saturations and porosity based on marine seismic and Controlled-Source Electromagnetic data. The multi-chain Markov-chain Monte Carlo is scalable in terms of the number of chains, and is useful for computationally demanding Bayesian model calibration in scientific and engineering problems. As a demonstration, the approach is used to efficiently and accurately estimate the porosity and saturations in a representative layered synthetic reservoir. The results indicate that the seismic Amplitude Versus Angle and Controlled-Source Electromagnetic joint inversion provides better estimation of reservoir saturations than the seismic Amplitude Versus Angle only inversion, especially for the parameters in deep layers. The performance of the inversion approach for various levels of noise in observational data was evaluated - reasonable estimates can be obtained with noise levels up to 25%. Sampling efficiency due to the use of multiple chains was also checked and was found to have almost linear scalability.

Parallel Task Processing on a Multicore Platform in a PC-based Control System for Parallel Kinematics

Directory of Open Access Journals (Sweden)

Harald Michalik

2009-02-01

Full Text Available Multicore platforms are such that have one physical processor chip with multiple cores interconnected via a chip level bus. Because they deliver a greater computing power through concurrency, offer greater system density multicore platforms provide best qualifications to address the performance bottleneck encountered in PC-based control systems for parallel kinematic robots with heavy CPU-load. Heavy load control tasks are generated by new control approaches that include features like singularity prediction, structure control algorithms, vision data integration and similar tasks. In this paper we introduce the parallel task scheduling extension of a communication architecture specially tailored for the development of PC-based control of parallel kinematics. The Sche-duling is specially designed for the processing on a multicore platform. It breaks down the serial task processing of the robot control cycle and extends it with parallel task processing paths in order to enhance the overall control performance.

Concurrent particle-in-cell plasma simulation on a multi-transputer parallel computer

International Nuclear Information System (INIS)

Khare, A.N.; Jethra, A.; Patel, Kartik

1992-01-01

This report describes the parallelization of a Particle-in-Cell (PIC) plasma simulation code on a multi-transputer parallel computer. The algorithm used in the parallelization of the PIC method is described. The decomposition schemes related to the distribution of the particles among the processors are discussed. The implementation of the algorithm on a transputer network connected as a torus is presented. The solutions of the problems related to global communication of data are presented in the form of a set of generalized communication functions. The performance of the program as a function of data size and the number of transputers show that the implementation is scalable and represents an effective way of achieving high performance at acceptable cost. (author). 11 refs., 4 figs., 2 tabs., appendices

Dynamic and Control Analysis of Modular Multi-Parallel Rectifiers (MMR)

DEFF Research Database (Denmark)

Zare, Firuz; Ghosh, Arindam; Davari, Pooya

2017-01-01

This paper presents dynamic analysis of a Modular Multi-Parallel Rectifier (MMR) based on state-space modelling and analysis. The proposed topology is suitable for high power application which can reduce line current harmonics emissions significantly. However, a proper controller is required...... to share and control current through each rectifier. Mathematical analysis and preliminary simulations have been carried out to verify the proposed controller under different operating conditions....

Large-Scale, Parallel, Multi-Sensor Atmospheric Data Fusion Using Cloud Computing

Science.gov (United States)

Wilson, B. D.; Manipon, G.; Hua, H.; Fetzer, E. J.

2013-12-01

NASA's Earth Observing System (EOS) is an ambitious facility for studying global climate change. The mandate now is to combine measurements from the instruments on the 'A-Train' platforms (AIRS, AMSR-E, MODIS, MISR, MLS, and CloudSat) and other Earth probes to enable large-scale studies of climate change over decades. Moving to multi-sensor, long-duration analyses of important climate variables presents serious challenges for large-scale data mining and fusion. For example, one might want to compare temperature and water vapor retrievals from one instrument (AIRS) to another (MODIS), and to a model (MERRA), stratify the comparisons using a classification of the 'cloud scenes' from CloudSat, and repeat the entire analysis over 10 years of data. To efficiently assemble such datasets, we are utilizing Elastic Computing in the Cloud and parallel map/reduce-based algorithms. However, these problems are Data Intensive computing so the data transfer times and storage costs (for caching) are key issues. SciReduce is a Hadoop-like parallel analysis system, programmed in parallel python, that is designed from the ground up for Earth science. SciReduce executes inside VMWare images and scales to any number of nodes in the Cloud. Unlike Hadoop, SciReduce operates on bundles of named numeric arrays, which can be passed in memory or serialized to disk in netCDF4 or HDF5. Figure 1 shows the architecture of the full computational system, with SciReduce at the core. Multi-year datasets are automatically 'sharded' by time and space across a cluster of nodes so that years of data (millions of files) can be processed in a massively parallel way. Input variables (arrays) are pulled on-demand into the Cloud using OPeNDAP URLs or other subsetting services, thereby minimizing the size of the cached input and intermediate datasets. We are using SciReduce to automate the production of multiple versions of a ten-year A-Train water vapor climatology under a NASA MEASURES grant. We will

Representation and shape estimation of Odin, a parallel under-actuated modular robot

DEFF Research Database (Denmark)

Lyder, Andreas; Petersen, Henrik Gordon; Støy, Kasper

2009-01-01

To understand the capabilities and behavior of a robot it is important to have knowledge about its physical structure and how its actuators control its shape. In this paper we analyze the kinematics and develop a general representation of a configuration of the heterogeneous modular robot Odin....... The basics of estimating the shape of the Odin robot is presented, which leads the way for further research on the Odin robot and similar robots. We present an example of how to represent and estimate the shape of a tetrahedron configuration with various types of modules. We conclude that this representation...... can be used to find the physical constraints of the Odin robot and estimate the shape of a configuration....

Multi-functionalized side-chain supramolecular polymers: A methodology towards tunable functional materials

Science.gov (United States)

Nair, Kamlesh Prabhakaran

Even as we see a significant growth in the field of supramolecular polymers in the last ten years, multi-functionalized systems have been scarcely studied. Noncovalent multi-functionalization provides unique advantages such as rapid materials optimization via reversible functionalization as well as for the tuning of materials properties by exploiting the differences in the nature of these reversible interactions. This thesis involves the design principles, synthesis & methodology of supramolecular side-chain multi-functionalized polymers. The combination of a functionally tolerant & controlled polymerization technique such as ROMP with multiple noncovalent interactions such as hydrogen bonding, metal coordination and ionic interactions has been successfully used to synthesize these polymers. Furthermore, the orthogonality between the above interactions in block/random copolymers has been studied in detail. It has been found that the studied interactions were orthogonal to each other. To validate the viability of this methodology using multiple orthogonal interactions towards materials design noncovalent crosslinking of polymers has been used as a potential application. Three classes of networks have been studied: complementary multiple hydrogen bonded networks, metal crosslinked networks, & multi-functionalized hydrogen bonded and metal coordinated networks. The first room temperature decrosslinking by exclusive complementary hydrogen bonded interactions has been successfully achieved. Furthermore network properties have been successfully tuned by varying the network micro-structure which in turn was tuned by the hydrogen bonding motifs used for inter-chain crosslinking. By combining two different noncovalent interactions used for inter-chain crosslinking, it was possible to make multi-functionalized materials whose properties could be controlled by varying the crosslinking strategy. Hence by employing multi-functionalization methodology, important materials

ALLIANCE: An architecture for fault tolerant multi-robot cooperation

Energy Technology Data Exchange (ETDEWEB)

Parker, L.E.

1995-02-01

ALLIANCE is a software architecture that facilitates the fault tolerant cooperative control of teams of heterogeneous mobile robots performing missions composed of loosely coupled, largely independent subtasks. ALLIANCE allows teams of robots, each of which possesses a variety of high-level functions that it can perform during a mission, to individually select appropriate actions throughout the mission based on the requirements of the mission, the activities of other robots, the current environmental conditions, and the robot`s own internal states. ALLIANCE is a fully distributed, behavior-based architecture that incorporates the use of mathematically modeled motivations (such as impatience and acquiescence) within each robot to achieve adaptive action selection. Since cooperative robotic teams usually work in dynamic and unpredictable environments, this software architecture allows the robot team members to respond robustly, reliably, flexibly, and coherently to unexpected environmental changes and modifications in the robot team that may occur due to mechanical failure, the learning of new skills, or the addition or removal of robots from the team by human intervention. The feasibility of this architecture is demonstrated in an implementation on a team of mobile robots performing a laboratory version of hazardous waste cleanup.

A MOORA based fuzzy multi-criteria decision making approach for supply chain strategy selection

Directory of Open Access Journals (Sweden)

Bijan Sarkar

2012-08-01

Full Text Available To acquire the competitive advantages in order to survive in the global business scenario, modern companies are now facing the problems of selecting key supply chain strategies. Strategy selection becomes difficult as the number of alternatives and conflicting criteria increases. Multi criteria decision making (MCDM methodologies help the supply chain managers take a lead in a complex industrial set-up. The present investigation applies fuzzy MCDM technique entailing multi-objective optimization on the basis of ratio analysis (MOORA in selection of alternatives in a supply chain. The MOORA method is utilized to three suitable numerical examples for the selection of supply chain strategies (warehouse location selection and vendor/supplier selection. The results obtained by using current approach almost match with those of previous research works published in various open journals. The empirical study has demonstrated the simplicity and applicability of this method as a strategic decision making tool in a supply chain.

A new decomposition method for parallel processing multi-level optimization

International Nuclear Information System (INIS)

Park, Hyung Wook; Kim, Min Soo; Choi, Dong Hoon

2002-01-01

In practical designs, most of the multidisciplinary problems have a large-size and complicate design system. Since multidisciplinary problems have hundreds of analyses and thousands of variables, the grouping of analyses and the order of the analyses in the group affect the speed of the total design cycle. Therefore, it is very important to reorder and regroup the original design processes in order to minimize the total computational cost by decomposing large multidisciplinary problems into several MultiDisciplinary Analysis SubSystems (MDASS) and by processing them in parallel. In this study, a new decomposition method is proposed for parallel processing of multidisciplinary design optimization, such as Collaborative Optimization (CO) and Individual Discipline Feasible (IDF) method. Numerical results for two example problems are presented to show the feasibility of the proposed method

Large-Scale, Parallel, Multi-Sensor Data Fusion in the Cloud

Science.gov (United States)

Wilson, B. D.; Manipon, G.; Hua, H.

2012-12-01

NASA's Earth Observing System (EOS) is an ambitious facility for studying global climate change. The mandate now is to combine measurements from the instruments on the "A-Train" platforms (AIRS, AMSR-E, MODIS, MISR, MLS, and CloudSat) and other Earth probes to enable large-scale studies of climate change over periods of years to decades. However, moving from predominantly single-instrument studies to a multi-sensor, measurement-based model for long-duration analysis of important climate variables presents serious challenges for large-scale data mining and data fusion. For example, one might want to compare temperature and water vapor retrievals from one instrument (AIRS) to another instrument (MODIS), and to a model (ECMWF), stratify the comparisons using a classification of the "cloud scenes" from CloudSat, and repeat the entire analysis over years of AIRS data. To perform such an analysis, one must discover & access multiple datasets from remote sites, find the space/time "matchups" between instruments swaths and model grids, understand the quality flags and uncertainties for retrieved physical variables, assemble merged datasets, and compute fused products for further scientific and statistical analysis. To efficiently assemble such decade-scale datasets in a timely manner, we are utilizing Elastic Computing in the Cloud and parallel map/reduce-based algorithms. "SciReduce" is a Hadoop-like parallel analysis system, programmed in parallel python, that is designed from the ground up for Earth science. SciReduce executes inside VMWare images and scales to any number of nodes in the Cloud. Unlike Hadoop, in which simple tuples (keys & values) are passed between the map and reduce functions, SciReduce operates on bundles of named numeric arrays, which can be passed in memory or serialized to disk in netCDF4 or HDF5. Thus, SciReduce uses the native datatypes (geolocated grids, swaths, and points) that geo-scientists are familiar with. We are deploying within Sci

A 3-DOF parallel robot with spherical motion for the rehabilitation and evaluation of balance performance.

Science.gov (United States)

Patanè, Fabrizio; Cappa, Paolo

2011-04-01

In this paper a novel electrically actuated parallel robot with three degrees-of-freedom (3 DOF) for dynamic postural studies is presented. The design has been described, the solution to the inverse kinematics has been found, and a numerical solution for the direct kinematics has been proposed. The workspace of the implemented robot is characterized by an angular range of motion of about ±10° for roll and pitch when yaw is in the range ±15°. The robot was constructed and the orientation accuracy was tested by means of an optoelectronic system and by imposing a sinusoidal input, with a frequency of 1 Hz and amplitude of 10°, along the three axes, in sequence. The collected data indicated a phase delay of 1° and an amplitude error of 0.5%-1.5%; similar values were observed for cross-axis sensitivity errors. We also conducted a clinical application on a group of normal subjects, who were standing in equilibrium on the robot base with eyes open (EO) and eyes closed (EC), which was rotated with a tri-axial sinusoidal trajectory with a frequency of 0.5 Hz and amplitude 5° for roll and pitch and 10° for the yaw. The postural configuration of the subjects was recorded with an optoelectronic system. However, due to the mainly technical nature of this paper, only initial validation outcomes are reported here. The clinical application showed that only the tilt and displacement on the sagittal pane of head, trunk, and pelvis in the trials conducted with eyes closed were affected by drift and that the reduction of the yaw rotation and of the mediolateral translation was not a controlled parameter, as happened, instead, for the other anatomical directions.

R3D3 in the Wild: Using A Robot for Turn Management in Multi-Party Interaction with a Virtual Human

NARCIS (Netherlands)

Theune, Mariet; Wiltenburg, Daan; Bode, Max; Linssen, Jeroen

R3D3 is a combination of a virtual human with a non-speaking robot capable of head gestures and emotive gaze behaviour. We use the robot to implement various turn management functions for use in multi-party interaction with R3D3, and present the results of a field study investigating their effects

Mobile robot multi-sensor unit for unsupervised gas discrimination in uncontrolled environments

OpenAIRE

Xing, Yuxin; Vincent, Timothy A.; Cole, Marina; Gardner, Julian W.; Fan, Han; Hernandez Bennetts, Victor; Schaffernicht, Erik; Lilienthal, Achim

2017-01-01

In this work we present a novel multi-sensor unit to detect and discriminate unknown gases in uncontrolled environments. The unit includes three metal oxide (MOX) sensors with CMOS micro heaters, a plasmonic enhanced non-dispersive infra-red (NDIR) sensor, a commercial temperature humidity sensor, and a flow sensor. The proposed sensing unit was evaluated with plumes of gases (propanol, ethanol and acetone) in both, a laboratory setup on a gas testing bench and on-board a mobile robot operati...

An integrated multi-stage supply chain inventory model with imperfect production process

Directory of Open Access Journals (Sweden)

Soumita Kundu

2015-09-01

Full Text Available This paper deals with an integrated multi-stage supply chain inventory model with the objective of cost minimization by synchronizing the replenishment decisions for procurement, production and delivery activities. The supply chain structure examined here consists of a single manufacturer with multi-buyer where manufacturer orders a fixed quantity of raw material from outside suppliers, processes the materials and delivers the finished products in unequal shipments to each customer. In this paper, we consider an imperfect production system, which produces defective items randomly and assumes that all defective items could be reworked. A simple algorithm is developed to obtain an optimal production policy, which minimizes the expected average total cost of the integrated production-inventory system.

Bayesian inversion of seismic and electromagnetic data for marine gas reservoir characterization using multi-chain Markov chain Monte Carlo sampling

Energy Technology Data Exchange (ETDEWEB)

Ren, Huiying; Ray, Jaideep; Hou, Zhangshuan; Huang, Maoyi; Bao, Jie; Swiler, Laura

2017-12-01

In this study we developed an efficient Bayesian inversion framework for interpreting marine seismic amplitude versus angle (AVA) and controlled source electromagnetic (CSEM) data for marine reservoir characterization. The framework uses a multi-chain Markov-chain Monte Carlo (MCMC) sampler, which is a hybrid of DiffeRential Evolution Adaptive Metropolis (DREAM) and Adaptive Metropolis (AM) samplers. The inversion framework is tested by estimating reservoir-fluid saturations and porosity based on marine seismic and CSEM data. The multi-chain MCMC is scalable in terms of the number of chains, and is useful for computationally demanding Bayesian model calibration in scientific and engineering problems. As a demonstration, the approach is used to efficiently and accurately estimate the porosity and saturations in a representative layered synthetic reservoir. The results indicate that the seismic AVA and CSEM joint inversion provides better estimation of reservoir saturations than the seismic AVA-only inversion, especially for the parameters in deep layers. The performance of the inversion approach for various levels of noise in observational data was evaluated – reasonable estimates can be obtained with noise levels up to 25%. Sampling efficiency due to the use of multiple chains was also checked and was found to have almost linear scalability.

ALLIANCE: An architecture for fault tolerant multi-robot cooperation

International Nuclear Information System (INIS)

Parker, L.E.

1995-02-01

ALLIANCE is a software architecture that facilitates the fault tolerant cooperative control of teams of heterogeneous mobile robots performing missions composed of loosely coupled, largely independent subtasks. ALLIANCE allows teams of robots, each of which possesses a variety of high-level functions that it can perform during a mission, to individually select appropriate actions throughout the mission based on the requirements of the mission, the activities of other robots, the current environmental conditions, and the robot's own internal states. ALLIANCE is a fully distributed, behavior-based architecture that incorporates the use of mathematically modeled motivations (such as impatience and acquiescence) within each robot to achieve adaptive action selection. Since cooperative robotic teams usually work in dynamic and unpredictable environments, this software architecture allows the robot team members to respond robustly, reliably, flexibly, and coherently to unexpected environmental changes and modifications in the robot team that may occur due to mechanical failure, the learning of new skills, or the addition or removal of robots from the team by human intervention. The feasibility of this architecture is demonstrated in an implementation on a team of mobile robots performing a laboratory version of hazardous waste cleanup

Parallel processing architecture for H.264 deblocking filter on multi-core platforms

Science.gov (United States)

Prasad, Durga P.; Sonachalam, Sekar; Kunchamwar, Mangesh K.; Gunupudi, Nageswara Rao

2012-03-01

Massively parallel computing (multi-core) chips offer outstanding new solutions that satisfy the increasing demand for high resolution and high quality video compression technologies such as H.264. Such solutions not only provide exceptional quality but also efficiency, low power, and low latency, previously unattainable in software based designs. While custom hardware and Application Specific Integrated Circuit (ASIC) technologies may achieve lowlatency, low power, and real-time performance in some consumer devices, many applications require a flexible and scalable software-defined solution. The deblocking filter in H.264 encoder/decoder poses difficult implementation challenges because of heavy data dependencies and the conditional nature of the computations. Deblocking filter implementations tend to be fixed and difficult to reconfigure for different needs. The ability to scale up for higher quality requirements such as 10-bit pixel depth or a 4:2:2 chroma format often reduces the throughput of a parallel architecture designed for lower feature set. A scalable architecture for deblocking filtering, created with a massively parallel processor based solution, means that the same encoder or decoder will be deployed in a variety of applications, at different video resolutions, for different power requirements, and at higher bit-depths and better color sub sampling patterns like YUV, 4:2:2, or 4:4:4 formats. Low power, software-defined encoders/decoders may be implemented using a massively parallel processor array, like that found in HyperX technology, with 100 or more cores and distributed memory. The large number of processor elements allows the silicon device to operate more efficiently than conventional DSP or CPU technology. This software programing model for massively parallel processors offers a flexible implementation and a power efficiency close to that of ASIC solutions. This work describes a scalable parallel architecture for an H.264 compliant deblocking

Multi-Robot FastSLAM for Large Domains

National Research Council Canada - National Science Library

Koperski, Choyong G

2007-01-01

For a robot to build a map of its surrounding area, it must have accurate position information within the area, and to obtain accurate position information within the area, the robot needs to have an...

A Case-Study for Life-Long Learning and Adaptation in Cooperative Robot Teams

International Nuclear Information System (INIS)

Parker, L.E.

1999-01-01

While considerable progress has been made in recent years toward the development of multi-robot teams, much work remains to be done before these teams are used widely in real-world applications. Two particular needs toward this end are the development of mechanisms that enable robot teams to generate cooperative behaviors on their own, and the development of techniques that allow these teams to autonomously adapt their behavior over time as the environment or the robot team changes. This paper proposes the use of the Cooperative Multi-Robot Observation of Multiple Moving Targets (CMOMMT) application as a rich domain for studying the issues of multi-robot learning and adaptation. After discussing the need for learning and adaptation in multi-robot teams, this paper describes the CMOMMT application and its relevance to multi-robot learning. We discuss the results of the previously- developed, hand-generated algorithm for CMOMMT and the potential for learning that was discovered from the hand-generated approach. We then describe the early work that has been done (by us and others) to generate multi- robot learning techniques for the CMOMMT application, as well as our ongoing research to develop approaches that give performance as good, or better, than the hand-generated approach. The ultimate goal of this research is to develop techniques for multi-robot learning and adaptation in the CMOMMT application domain that will generalize to cooperative robot applications in other domains, thus making the practical use of multi-robot teams in a wide variety of real-world applications much closer to reality

Exploring backbone-cation alkyl spacers for multi-cation side chain anion exchange membranes

Science.gov (United States)

Zhu, Liang; Yu, Xuedi; Hickner, Michael A.

2018-01-01

In order to systematically study how the arrangement of cations on the side chain and length of alkyl spacers between cations impact the performance of multi-cation AEMs for alkaline fuel cells, a series of polyphenylene oxide (PPO)-based AEMs with different cationic side chains were synthesized. This work resulted in samples with two or three cations in a side chain pendant to the PPO backbone. More importantly, the length of the spacer between cations varied from 3 methylene (-CH2-) (C3) groups to 8 methylene (C8) groups. The highest conductivity, up to 99 mS/cm in liquid water at room temperature, was observed for the triple-cation side chain AEM with pentyl (C5) or hexyl (C6) spacers. The multi-cation AEMs were found to have decreased water uptake and ionic conductivity when the spacer chains between cations were lengthened from pentyl (C5) or hexyl (C6) to octyl (C8) linking groups. The triple-cation membranes with pentyl (C5) or hexyl (C6) groups between cations showed greatest stability after immersion in 1 M NaOH at 80 °C for 500 h.

Integrated multi-sensory control of space robot hand

Science.gov (United States)

Bejczy, A. K.; Kan, E. P.; Killion, R. R.

1985-01-01

Dexterous manipulation of a robot hand requires the use of multiple sensors integrated into the mechanical hand under distributed microcomputer control. Where space applications such as construction, assembly, servicing and repair tasks are desired of smart robot arms and robot hands, several critical drives influence the design, engineering and integration of such an electromechanical hand. This paper describes a smart robot hand developed at the Jet Propulsion Laboratory for experimental use and evaluation with the Protoflight Manipulator Arm (PFMA) at the Marshall Space Flight Center (MSFC).

A Low-Cost Open Source 3D-Printable Dexterous Anthropomorphic Robotic Hand with a Parallel Spherical Joint Wrist for Sign Languages Reproduction

Directory of Open Access Journals (Sweden)

Andrea Bulgarelli

2016-06-01

Full Text Available We present a novel open-source 3D-printable dexterous anthropomorphic robotic hand specifically designed to reproduce Sign Languages’ hand poses for deaf and deaf-blind users. We improved the InMoov hand, enhancing dexterity by adding abduction/adduction degrees of freedom of three fingers (thumb, index and middle fingers and a three-degrees-of-freedom parallel spherical joint wrist. A systematic kinematic analysis is provided. The proposed robotic hand is validated in the framework of the PARLOMA project. PARLOMA aims at developing a telecommunication system for deaf-blind people, enabling remote transmission of signs from tactile Sign Languages. Both hardware and software are provided online to promote further improvements from the community.

Parallel Atomistic Simulations

Energy Technology Data Exchange (ETDEWEB)

HEFFELFINGER,GRANT S.

2000-01-18

Algorithms developed to enable the use of atomistic molecular simulation methods with parallel computers are reviewed. Methods appropriate for bonded as well as non-bonded (and charged) interactions are included. While strategies for obtaining parallel molecular simulations have been developed for the full variety of atomistic simulation methods, molecular dynamics and Monte Carlo have received the most attention. Three main types of parallel molecular dynamics simulations have been developed, the replicated data decomposition, the spatial decomposition, and the force decomposition. For Monte Carlo simulations, parallel algorithms have been developed which can be divided into two categories, those which require a modified Markov chain and those which do not. Parallel algorithms developed for other simulation methods such as Gibbs ensemble Monte Carlo, grand canonical molecular dynamics, and Monte Carlo methods for protein structure determination are also reviewed and issues such as how to measure parallel efficiency, especially in the case of parallel Monte Carlo algorithms with modified Markov chains are discussed.

Extensions of Parallel Coordinates for Interactive Exploration of Large Multi-Timepoint Data Sets

NARCIS (Netherlands)

Blaas, J.; Botha, C.P.; Post, F.H.

2008-01-01

Parallel coordinate plots (PCPs) are commonly used in information visualization to provide insight into multi-variate data. These plots help to spot correlations between variables. PCPs have been successfully applied to unstructured datasets up to a few millions of points. In this paper, we present

A Hybrid FPGA/Coarse Parallel Processing Architecture for Multi-modal Visual Feature Descriptors

DEFF Research Database (Denmark)

Jensen, Lars Baunegaard With; Kjær-Nielsen, Anders; Alonso, Javier Díaz

2008-01-01

This paper describes the hybrid architecture developed for speeding up the processing of so-called multi-modal visual primitives which are sparse image descriptors extracted along contours. In the system, the first stages of visual processing are implemented on FPGAs due to their highly parallel...

Multi-Sensor SLAM Approach for Robot Navigation

Directory of Open Access Journals (Sweden)

Sid Ahmed BERRABAH

2010-12-01

Full Text Available o be able to operate and act successfully, the robot needs to know at any time where it is. This means the robot has to find out its location relative to the environment. This contribution introduces the increase of accuracy of mobile robot positioning in large outdoor environments based on data fusion from different sensors: camera, GPS, inertial navigation system (INS, and wheel encoders. The fusion is done in a Simultaneous Localization and Mapping (SLAM approach. The paper gives an overview on the proposed algorithm and discusses the obtained results.

Computational cost of isogeometric multi-frontal solvers on parallel distributed memory machines

KAUST Repository

Woźniak, Maciej

2015-02-01

This paper derives theoretical estimates of the computational cost for isogeometric multi-frontal direct solver executed on parallel distributed memory machines. We show theoretically that for the Cp-1 global continuity of the isogeometric solution, both the computational cost and the communication cost of a direct solver are of order O(log(N)p2) for the one dimensional (1D) case, O(Np2) for the two dimensional (2D) case, and O(N4/3p2) for the three dimensional (3D) case, where N is the number of degrees of freedom and p is the polynomial order of the B-spline basis functions. The theoretical estimates are verified by numerical experiments performed with three parallel multi-frontal direct solvers: MUMPS, PaStiX and SuperLU, available through PETIGA toolkit built on top of PETSc. Numerical results confirm these theoretical estimates both in terms of p and N. For a given problem size, the strong efficiency rapidly decreases as the number of processors increases, becoming about 20% for 256 processors for a 3D example with 1283 unknowns and linear B-splines with C0 global continuity, and 15% for a 3D example with 643 unknowns and quartic B-splines with C3 global continuity. At the same time, one cannot arbitrarily increase the problem size, since the memory required by higher order continuity spaces is large, quickly consuming all the available memory resources even in the parallel distributed memory version. Numerical results also suggest that the use of distributed parallel machines is highly beneficial when solving higher order continuity spaces, although the number of processors that one can efficiently employ is somehow limited.

Position Based Visual Servoing control of a Wheelchair Mounter Robotic Arm using Parallel Tracking and Mapping of task objects

Directory of Open Access Journals (Sweden)

Alessandro Palla

2017-05-01

Full Text Available In the last few years power wheelchairs have been becoming the only device able to provide autonomy and independence to people with motor skill impairments. In particular, many power wheelchairs feature robotic arms for gesture emulation, like the interaction with objects. However, complex robotic arms often require a joystic to be controlled; this feature make the arm hard to be controlled by impaired users. Paradoxically, if the user were able to proficiently control such devices, he would not need them. For that reason, this paper presents a highly autonomous robotic arm, designed in order to minimize the effort necessary for the control of the arm. In order to do that, the arm feature an easy to use human - machine interface and is controlled by Computer Vison algorithm, implementing a Position Based Visual Servoing (PBVS control. It was realized by extracting features by the camera and fusing them with the distance from the target, obtained by a proximity sensor. The Parallel Tracking and Mapping (PTAM algorithm was used to find the 3D position of the task object in the camera reference system. The visual servoing algorithm was implemented in an embedded platform, in real time. Each part of the control loop was developed in Robotic Operative System (ROS Environment, which allows to implement the previous algorithms as different nodes. Theoretical analysis, simulations and in system measurements proved the effectiveness of the proposed solution.

Dynamic supply chain network design with capacity planning and multi-period pricing

DEFF Research Database (Denmark)

Fattahi, Mohammad; Mahootchi, Masoud; Govindan, Kannan

2015-01-01

This paper addresses a new problem in designing and planning a multi-echelon and multi-product supply chain network over a multi-period horizon in which customer zones have price-sensitive demands. Based on price-demand relationships, a generic method is presented to obtain price levels...... for products and then, a mixed-integer linear programming model is developed. Due to the problem intractability, a simulated annealing algorithm that uses some developed linear relaxation-based heuristics for capacity planning and pricing is presented. Numerical results demonstrate the significance...

Colias: An Autonomous Micro Robot for Swarm Robotic Applications

Directory of Open Access Journals (Sweden)

Farshad Arvin

2014-07-01

Full Text Available Robotic swarms that take inspiration from nature are becoming a fascinating topic for multi-robot researchers. The aim is to control a large number of simple robots in order to solve common complex tasks. Due to the hardware complexities and cost of robot platforms, current research in swarm robotics is mostly performed by simulation software. The simulation of large numbers of these robots in robotic swarm applications is extremely complex and often inaccurate due to the poor modelling of external conditions. In this paper, we present the design of a low-cost, open-platform, autonomous micro-robot (Colias for robotic swarm applications. Colias employs a circular platform with a diameter of 4 cm. It has a maximum speed of 35 cm/s which enables it to be used in swarm scenarios very quickly over large arenas. Long-range infrared modules with an adjustable output power allow the robot to communicate with its direct neighbours at a range of 0.5 cm to 2 m. Colias has been designed as a complete platform with supporting software development tools for robotics education and research. It has been tested in both individual and swarm scenarios, and the observed results demonstrate its feasibility for use as a micro-sized mobile robot and as a low-cost platform for robot swarm applications.

Integration of Fiber-Optic Sensor Arrays into a Multi-Modal Tactile Sensor Processing System for Robotic End-Effectors

Directory of Open Access Journals (Sweden)

Peter Kampmann

2014-04-01

Full Text Available With the increasing complexity of robotic missions and the development towards long-term autonomous systems, the need for multi-modal sensing of the environment increases. Until now, the use of tactile sensor systems has been mostly based on sensing one modality of forces in the robotic end-effector. The use of a multi-modal tactile sensory system is motivated, which combines static and dynamic force sensor arrays together with an absolute force measurement system. This publication is focused on the development of a compact sensor interface for a fiber-optic sensor array, as optic measurement principles tend to have a bulky interface. Mechanical, electrical and software approaches are combined to realize an integrated structure that provides decentralized data pre-processing of the tactile measurements. Local behaviors are implemented using this setup to show the effectiveness of this approach.

Multi-area market clearing in wind-integrated interconnected power systems: A fast parallel decentralized method

International Nuclear Information System (INIS)

Doostizadeh, Meysam; Aminifar, Farrokh; Lesani, Hamid; Ghasemi, Hassan

2016-01-01

Highlights: • A parallel-decentralized multi-area energy & reserve clearance model is proposed. • A fictitious area and joint variables coordinate & parallelize area market models. • Adjustable intervals of random variables compromise optimality and robustness. • The stochastic nature of problem is tackled in an efficient deterministic manner. • The model is compact and applicable in multi-area real-scale systems. - Abstract: The growing evolution of regional electricity markets and proliferation of wind power penetration underline the prominence of coordinated operation of interconnected regional power systems. This paper develops a parallel decentralized methodology for multi-area energy and reserve clearance under wind power uncertainty. Preserving the independency of regional markets while fully taking the advantages of interconnection is a salient feature of the new model. Additionally, the parallel procedure simultaneously clears regional markets for the sake of acceleration particularly in large-scale systems. In order to achieve the optimal solution in a distributed fashion, the augmented Lagrangian relaxation along with alternative direction method of multipliers are applied. The wind power intermittency and uncertainty are tackled through the interval optimization approach. Opposed to the conventional wisdom, adjustable intervals, as subsets of conventional predefined intervals, are introduced here to compromise the cost and conservatism of the solution. The confidence level approach is employed to accommodate the stochastic nature of wind power in a computationally efficient deterministic manner. The effectiveness and robustness of the proposed method are evaluated through several case studies on a two-area 6-bus and the modified three-area IEEE 118-bus test systems.

Morphology Independent Learning in Modular Robots

DEFF Research Database (Denmark)

Christensen, David Johan; Bordignon, Mirko; Schultz, Ulrik Pagh

2009-01-01

speed its modules independently and in parallel adjust their behavior based on a single global reward signal. In simulation, we study the learning strategy’s performance on different robot configurations. On the physical platform, we perform learning experiments with ATRON robots learning to move as fast...

Morphology Independent Learning in Modular Robots

DEFF Research Database (Denmark)

Christensen, David Johan; Bordignon, Mirko; Schultz, Ulrik Pagh

2009-01-01

speed its modules independently and in parallel adjust their behavior based on a single global reward signal. In simulation, we study the learning strategy?s performance on different robot con?gurations. On the physical platform, we perform learning experiments with ATRON robots learning to move as fast...

A Human-Robot Interaction Perspective on Assistive and Rehabilitation Robotics.

Science.gov (United States)

Beckerle, Philipp; Salvietti, Gionata; Unal, Ramazan; Prattichizzo, Domenico; Rossi, Simone; Castellini, Claudio; Hirche, Sandra; Endo, Satoshi; Amor, Heni Ben; Ciocarlie, Matei; Mastrogiovanni, Fulvio; Argall, Brenna D; Bianchi, Matteo

2017-01-01

Assistive and rehabilitation devices are a promising and challenging field of recent robotics research. Motivated by societal needs such as aging populations, such devices can support motor functionality and subject training. The design, control, sensing, and assessment of the devices become more sophisticated due to a human in the loop. This paper gives a human-robot interaction perspective on current issues and opportunities in the field. On the topic of control and machine learning, approaches that support but do not distract subjects are reviewed. Options to provide sensory user feedback that are currently missing from robotic devices are outlined. Parallels between device acceptance and affective computing are made. Furthermore, requirements for functional assessment protocols that relate to real-world tasks are discussed. In all topic areas, the design of human-oriented frameworks and methods is dominated by challenges related to the close interaction between the human and robotic device. This paper discusses the aforementioned aspects in order to open up new perspectives for future robotic solutions.

Food chain design using multi criteria decision making, an approach to complex design issues

NARCIS (Netherlands)

Linnemann, A.R.; Hendrix, E.M.T.; Apaiah, R.K.; Boekel, van M.A.J.S.

2015-01-01

Designing a food supply chain for a completely new product involves many stakeholders and knowledge from disciplines in natural and social sciences. This paper describes how Multi Criteria Decision Making (MCDM) facilitated designing a food supply chain in a case of Novel Protein Foods. It made the

Diseño de modelo de patrullaje multi-robot basado en Teoría de Juegos para la protección de grandes infraestructuras

OpenAIRE

Alberte Rey, Marta

2015-01-01

Los sistemas multi-robot han sido objeto de numerosos estudios en los últimos años debido, entre otras razones, a su potencial aplicación en diferentes escenarios o misiones. Una de estas misiones, donde el uso de los sistemas multi-robot es de especial interés, es el desarrollo de tareas de seguridad y vigilancia en las denominadas “grandes infraestructuras críticas exteriores” que, entre otras necesidades, precisan tener bajo vigilancia áreas o puntos sensibles (accesos, zonas de mando, aco...

Expressing Parallelism with ROOT

Energy Technology Data Exchange (ETDEWEB)

Piparo, D. [CERN; Tejedor, E. [CERN; Guiraud, E. [CERN; Ganis, G. [CERN; Mato, P. [CERN; Moneta, L. [CERN; Valls Pla, X. [CERN; Canal, P. [Fermilab

2017-11-22

The need for processing the ever-increasing amount of data generated by the LHC experiments in a more efficient way has motivated ROOT to further develop its support for parallelism. Such support is being tackled both for shared-memory and distributed-memory environments. The incarnations of the aforementioned parallelism are multi-threading, multi-processing and cluster-wide executions. In the area of multi-threading, we discuss the new implicit parallelism and related interfaces, as well as the new building blocks to safely operate with ROOT objects in a multi-threaded environment. Regarding multi-processing, we review the new MultiProc framework, comparing it with similar tools (e.g. multiprocessing module in Python). Finally, as an alternative to PROOF for cluster-wide executions, we introduce the efforts on integrating ROOT with state-of-the-art distributed data processing technologies like Spark, both in terms of programming model and runtime design (with EOS as one of the main components). For all the levels of parallelism, we discuss, based on real-life examples and measurements, how our proposals can increase the productivity of scientists.

Expressing Parallelism with ROOT

Science.gov (United States)

Piparo, D.; Tejedor, E.; Guiraud, E.; Ganis, G.; Mato, P.; Moneta, L.; Valls Pla, X.; Canal, P.

2017-10-01

The need for processing the ever-increasing amount of data generated by the LHC experiments in a more efficient way has motivated ROOT to further develop its support for parallelism. Such support is being tackled both for shared-memory and distributed-memory environments. The incarnations of the aforementioned parallelism are multi-threading, multi-processing and cluster-wide executions. In the area of multi-threading, we discuss the new implicit parallelism and related interfaces, as well as the new building blocks to safely operate with ROOT objects in a multi-threaded environment. Regarding multi-processing, we review the new MultiProc framework, comparing it with similar tools (e.g. multiprocessing module in Python). Finally, as an alternative to PROOF for cluster-wide executions, we introduce the efforts on integrating ROOT with state-of-the-art distributed data processing technologies like Spark, both in terms of programming model and runtime design (with EOS as one of the main components). For all the levels of parallelism, we discuss, based on real-life examples and measurements, how our proposals can increase the productivity of scientists.

Simulation model of multi-compartment distribution in the catering supply chain

NARCIS (Netherlands)

Jansen, D.R.; Weert, van A.; Beulens, A.J.M.; Huirne, R.B.M.

2001-01-01

An efficient distribution system of high performance is needed to anticipate market developments in the catering supply chain (CSC) in the Netherlands. A simulation model was developed to analyse a multi-compartment distribution system which should satisfy customer demands for shorter lead times,

KINEMATICS ANALYSIS OF A PARALLEL ROBOT WITH A PASSIVE SEGMENT ANÁLISIS DE LA CINEMÁTICA DE UN ROBOT PARALELO CON UN SEGMENTO PASIVO

Directory of Open Access Journals (Sweden)

Abdelhakim Cherfia

2007-08-01

Full Text Available This paper presents a geometrical model of a constrained robot of three degrees of freedom (d.o.f added to a PPP passive central segment. This structure provides a pure translation motion. We will also determine the relations between generalized and articular velocities by using the inverse Jacobian matrix. Further, we determine the reciprocal relations between cartesian and angular velocities of the end-effector via articular velocities by simple derivation of the direct geometrical model expressions. A determination of the workspace based on the geometrical model analysis is derived followed by a numerical calculation of all the atteignables points enabling a graphical visualisation of such a workspace. Moreover, the analysis of the Jacobian matrix has permitted to ensure that there are no singularities of type 1 and 2 in such a structure. A prototype of a parallel robot has been built up in our laboratory in order to validate the proposed models.Este trabajo presenta el modelo geométrico de un robot paralelo con tres grados de libertad (d.o.f agregados a un segmento central pasivo del PPP. Esta estructura proporciona un movimiento de translación pura. También determinaremos las relaciones entre las velocidades generalizadas y articulares usando la matriz Jacobiana inversa. Además, determinamos las relaciones recíprocas entre las velocidades cartesianas y angulares del end-effector vía velocidades articulares por la derivación simple de las expresiones del modelo geométrico directo. Una determinación del espacio de trabajo basado en el análisis del modelo geométrico es derivado seguido por un cálculo numérico de todos los puntos que deben alcanzarse permitiendo una visualización gráfica de tal espacio de trabajo. Por otra parte, el análisis de los coeficientes de la matriz Jacobiana permite asegurar que no haya singularidades del tipo 1 y 2 en tal estructura. Se ha realizado un prototipo de robot paralelo en nuestro laboratorio

Partitioning of electron flux between the respiratory chains of the yeast Candida parapsilosis: parallel working of the two chains.

Science.gov (United States)

Guerin, M G; Camougrand, N M

1994-02-08

Partitioning of the electron flux between the classical and the alternative respiratory chains of the yeast Candida parapsilosis, was measured as a function of the oxidation rate and of the Q-pool redox poise. At low respiration rate, electrons from external NADH travelled preferentially through the alternative pathway as indicated by the antimycin A-insensitivity of electron flow. Inhibition of the alternative pathway by SHAM restored full antimycin A-sensitivity to the remaining electro flow. The dependence of the respiratory rate on the redox poise of the quinone pool was investigated when the electron flux was mediated either by the main respiratory chain (growth in the absence of antimycin A) or by the second respiratory chain (growth in the presence of antimycin A). In the former case, a linear relationship was found between these two parameters. In contrast, in the latter case, the relationship between Q-pool reduction level and electron flux was non-linear, but it could be resolved into two distinct curves. This second quinone is not reducible in the presence of antimycin A but only in the presence of high concentrations of myxothiazol or cyanide. Since two quinone species exist in C. parapsilosis, UQ9 and Qx (C33H54O4), we hypothesized that these two curves could correspond to the functioning of the second quinone engaged during the alternative pathway activity. Partitioning of electrons between both respiratory chains could occur upstream of complex III with the second chain functioning in parallel to the main one, and with the additional possibility of merging into the main one at the complex IV level.

Intelligent manipulation technique for multi-branch robotic systems

Science.gov (United States)

Chen, Alexander Y. K.; Chen, Eugene Y. S.

1990-01-01

New analytical development in kinematics planning is reported. The INtelligent KInematics Planner (INKIP) consists of the kinematics spline theory and the adaptive logic annealing process. Also, a novel framework of robot learning mechanism is introduced. The FUzzy LOgic Self Organized Neural Networks (FULOSONN) integrates fuzzy logic in commands, control, searching, and reasoning, the embedded expert system for nominal robotics knowledge implementation, and the self organized neural networks for the dynamic knowledge evolutionary process. Progress on the mechanical construction of SRA Advanced Robotic System (SRAARS) and the real time robot vision system is also reported. A decision was made to incorporate the Local Area Network (LAN) technology in the overall communication system.

Optimization and design of a laser-cutting machine using delta robot

OpenAIRE

Moharana, B.; Gupta, Rakesh; Kushwaha, Bashishth Kumar

2014-01-01

Industrial high speed laser operations the use of delta parallel robots potentially offers many benefits due to their structural stiffness and limited moving masses. This paper deals with a particular Delta, developed for high speed laser cutting. Parallel delta robot has numerous advantages in comparison with serial robots Higher stiffness and connected with that a lower mass of links the possibility of transporting heavier loads, and higher accuracy. The main drawback is however a smaller w...

Surgical outcomes of robot-assisted rectal cancer surgery using the da Vinci Surgical System: a multi-center pilot Phase II study.

Science.gov (United States)

Tsukamoto, Shunsuke; Nishizawa, Yuji; Ochiai, Hiroki; Tsukada, Yuichiro; Sasaki, Takeshi; Shida, Dai; Ito, Masaaki; Kanemitsu, Yukihide

2017-12-01

We conducted a multi-center pilot Phase II study to examine the safety of robotic rectal cancer surgery performed using the da Vinci Surgical System during the introduction period of robotic rectal surgery at two institutes based on surgical outcomes. This study was conducted with a prospective, multi-center, single-arm, open-label design to assess the safety and feasibility of robotic surgery for rectal cancer (da Vinci Surgical System). The primary endpoint was the rate of adverse events during and after robotic surgery. The secondary endpoint was the completion rate of robotic surgery. Between April 2014 and July 2016, 50 patients were enrolled in this study. Of these, 10 (20%) had rectosigmoid cancer, 17 (34%) had upper rectal cancer, and 23 (46%) had lower rectal cancer; six underwent high anterior resection, 32 underwent low anterior resection, 11 underwent intersphincteric resection, and one underwent abdominoperineal resection. Pathological stages were Stage 0 in 1 patient, Stage I in 28 patients, Stage II in 7 patients and Stage III in 14 patients. Pathologically complete resection was achieved in all patients. There was no intraoperative organ damage or postoperative mortality. Eight (16%) patients developed complications of all grades, of which 2 (4%) were Grade 3 or higher, including anastomotic leakage (2%) and conversion to open surgery (2%). The present study demonstrates the feasibility and safety of robotic rectal cancer surgery, as reflected by low morbidity and low conversion rates, during the introduction period. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

A Robotic Guide for Blind People. Part 1. A Multi-National Survey of the Attitudes, Requirements and Preferences of Potential End-Users

Directory of Open Access Journals (Sweden)

Marion A. Hersh

2010-01-01

Full Text Available This paper reports the results of a multi-national survey in several different countries on the attitudes, requirements and preferences of blind and visually impaired people for a robotic guide. The survey is introduced by a brief overview of existing work on robotic travel aids and other mobile robotic devices. The questionnaire comprises three sections on personal information about respondents, existing use of mobility and navigation devices and the functions and other features of a robotic guide. The survey found that respondents were very interested in the robotic guide having a number of different functions and being useful in a wide range of circumstances. They considered the robot's appearance to be very important but did not like any of the proposed designs. From their comments, respondents wanted the robot to be discreet and inconspicuous, small, light weight and portable, easy to use, robust to damage, require minimal maintenance, have a long life and a long battery life.

Computational cost estimates for parallel shared memory isogeometric multi-frontal solvers

KAUST Repository

Woźniak, Maciej; Kuźnik, Krzysztof M.; Paszyński, Maciej R.; Calo, Victor M.; Pardo, D.

2014-01-01

In this paper we present computational cost estimates for parallel shared memory isogeometric multi-frontal solvers. The estimates show that the ideal isogeometric shared memory parallel direct solver scales as O( p2log(N/p)) for one dimensional problems, O(Np2) for two dimensional problems, and O(N4/3p2) for three dimensional problems, where N is the number of degrees of freedom, and p is the polynomial order of approximation. The computational costs of the shared memory parallel isogeometric direct solver are compared with those corresponding to the sequential isogeometric direct solver, being the latest equal to O(N p2) for the one dimensional case, O(N1.5p3) for the two dimensional case, and O(N2p3) for the three dimensional case. The shared memory version significantly reduces both the scalability in terms of N and p. Theoretical estimates are compared with numerical experiments performed with linear, quadratic, cubic, quartic, and quintic B-splines, in one and two spatial dimensions. © 2014 Elsevier Ltd. All rights reserved.

Computational cost estimates for parallel shared memory isogeometric multi-frontal solvers

KAUST Repository

Woźniak, Maciej

2014-06-01

In this paper we present computational cost estimates for parallel shared memory isogeometric multi-frontal solvers. The estimates show that the ideal isogeometric shared memory parallel direct solver scales as O( p2log(N/p)) for one dimensional problems, O(Np2) for two dimensional problems, and O(N4/3p2) for three dimensional problems, where N is the number of degrees of freedom, and p is the polynomial order of approximation. The computational costs of the shared memory parallel isogeometric direct solver are compared with those corresponding to the sequential isogeometric direct solver, being the latest equal to O(N p2) for the one dimensional case, O(N1.5p3) for the two dimensional case, and O(N2p3) for the three dimensional case. The shared memory version significantly reduces both the scalability in terms of N and p. Theoretical estimates are compared with numerical experiments performed with linear, quadratic, cubic, quartic, and quintic B-splines, in one and two spatial dimensions. © 2014 Elsevier Ltd. All rights reserved.

A New Cancer Radiotherapy System Using Multi Robotic Manipulators

International Nuclear Information System (INIS)

Kim, Seung Ho; Lee, Nam Ho; Lee, Byung Chul; Jeung, Kyung Min; Lee, Seong Uk; Bae, Yeong Geol; Na, Hyun Seok

2013-01-01

The CyberKnife system is state-of-the-art cancer treatment equipment that combines an image tracking technique, artificial intelligence software, robot technology, accelerator technology, and treatment simulation technology. The current CyberKnife System has significant shortcomings. The biggest problem is that it takes a longer time to treat a tumor. A long treatment time gives stress to patients. Furthermore it makes the patients uncomfortable with radiation and thus it is difficult to measure the exact radiation dose rate to the tumor in the processing. Linear accelerators for radiation treatment are dependent on imports, and demand high maintenance cost. This also makes the treatment cost higher and prevents the popularization of radiation. To solve the disadvantages of the existing CyberKnife, a radiation treatment robot system applied to several articulated robots is suggested. Essential element techniques for new radiotherapy robot system are investigated and some problems of similar existing systems are analyzed. This paper presents a general configuration of a new radiation robot treatment system including with a quantitative goal of the requirement techniques. This paper described a new radiotherapy robot system to track the tumor using multiple articulated robots in real time. The existing CyberKnife system using a single robot arm has disadvantages of a long radiotherapy time, high medical fee, and inaccurate measurement of the radiotherapy dose. So a new radiotherapy robot system for tumors has been proposed to solve the above problems of conventional CyberKnife systems. Necessary technologies to configure new the radiotherapy robot system have been identified. Quantitative targets of each technology have been established. Multiple robot arms are adopted to decrease the radiotherapy time. The results of this research are provided as a requisite technology for a domestic radiotherapy system and are expected to be the foundation of new technology. The

A New Cancer Radiotherapy System Using Multi Robotic Manipulators

Energy Technology Data Exchange (ETDEWEB)

Kim, Seung Ho; Lee, Nam Ho; Lee, Byung Chul; Jeung, Kyung Min; Lee, Seong Uk; Bae, Yeong Geol; Na, Hyun Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

The CyberKnife system is state-of-the-art cancer treatment equipment that combines an image tracking technique, artificial intelligence software, robot technology, accelerator technology, and treatment simulation technology. The current CyberKnife System has significant shortcomings. The biggest problem is that it takes a longer time to treat a tumor. A long treatment time gives stress to patients. Furthermore it makes the patients uncomfortable with radiation and thus it is difficult to measure the exact radiation dose rate to the tumor in the processing. Linear accelerators for radiation treatment are dependent on imports, and demand high maintenance cost. This also makes the treatment cost higher and prevents the popularization of radiation. To solve the disadvantages of the existing CyberKnife, a radiation treatment robot system applied to several articulated robots is suggested. Essential element techniques for new radiotherapy robot system are investigated and some problems of similar existing systems are analyzed. This paper presents a general configuration of a new radiation robot treatment system including with a quantitative goal of the requirement techniques. This paper described a new radiotherapy robot system to track the tumor using multiple articulated robots in real time. The existing CyberKnife system using a single robot arm has disadvantages of a long radiotherapy time, high medical fee, and inaccurate measurement of the radiotherapy dose. So a new radiotherapy robot system for tumors has been proposed to solve the above problems of conventional CyberKnife systems. Necessary technologies to configure new the radiotherapy robot system have been identified. Quantitative targets of each technology have been established. Multiple robot arms are adopted to decrease the radiotherapy time. The results of this research are provided as a requisite technology for a domestic radiotherapy system and are expected to be the foundation of new technology. The

Sensor-guided parking system for a carlike robot

Science.gov (United States)

Jiang, Kaichum; Seneviratne, L. D.

1998-07-01

This paper presents an automated parking strategy for a car- like mobile robot. The study considers general parking manoeuvre cases for a rectangular robot, including parallel parking. The robot is constructed simulating a conventional car, which is subject to non-holonomic constraints and thus only has two degrees of freedom. The parking space is considered as rectangular, and detected by ultrasonic sensors mounted on the robot. A motion planning algorithm develops a collision-free path for parking, taking into account the non- holonomic constraints acting on the car-like robot. A research into general car maneuvers has been conducted and useful results have been achieved. The motion planning algorithm uses these results, combined with configuration space method, to produce a collision-free path for parallel parking, depending on the parking space detected. A control program in the form of a graphical user interface has been developed for users to operate the system with ease. The strategy is implemented on a modified B12 mobile robot. The strategy presented has the potential for application in automobiles.

Real-time SHVC software decoding with multi-threaded parallel processing

Science.gov (United States)

Gudumasu, Srinivas; He, Yuwen; Ye, Yan; He, Yong; Ryu, Eun-Seok; Dong, Jie; Xiu, Xiaoyu

2014-09-01

This paper proposes a parallel decoding framework for scalable HEVC (SHVC). Various optimization technologies are implemented on the basis of SHVC reference software SHM-2.0 to achieve real-time decoding speed for the two layer spatial scalability configuration. SHVC decoder complexity is analyzed with profiling information. The decoding process at each layer and the up-sampling process are designed in parallel and scheduled by a high level application task manager. Within each layer, multi-threaded decoding is applied to accelerate the layer decoding speed. Entropy decoding, reconstruction, and in-loop processing are pipeline designed with multiple threads based on groups of coding tree units (CTU). A group of CTUs is treated as a processing unit in each pipeline stage to achieve a better trade-off between parallelism and synchronization. Motion compensation, inverse quantization, and inverse transform modules are further optimized with SSE4 SIMD instructions. Simulations on a desktop with an Intel i7 processor 2600 running at 3.4 GHz show that the parallel SHVC software decoder is able to decode 1080p spatial 2x at up to 60 fps (frames per second) and 1080p spatial 1.5x at up to 50 fps for those bitstreams generated with SHVC common test conditions in the JCT-VC standardization group. The decoding performance at various bitrates with different optimization technologies and different numbers of threads are compared in terms of decoding speed and resource usage, including processor and memory.

Multi-petascale highly efficient parallel supercomputer

Science.gov (United States)

Asaad, Sameh; Bellofatto, Ralph E.; Blocksome, Michael A.; Blumrich, Matthias A.; Boyle, Peter; Brunheroto, Jose R.; Chen, Dong; Cher, Chen -Yong; Chiu, George L.; Christ, Norman; Coteus, Paul W.; Davis, Kristan D.; Dozsa, Gabor J.; Eichenberger, Alexandre E.; Eisley, Noel A.; Ellavsky, Matthew R.; Evans, Kahn C.; Fleischer, Bruce M.; Fox, Thomas W.; Gara, Alan; Giampapa, Mark E.; Gooding, Thomas M.; Gschwind, Michael K.; Gunnels, John A.; Hall, Shawn A.; Haring, Rudolf A.; Heidelberger, Philip; Inglett, Todd A.; Knudson, Brant L.; Kopcsay, Gerard V.; Kumar, Sameer; Mamidala, Amith R.; Marcella, James A.; Megerian, Mark G.; Miller, Douglas R.; Miller, Samuel J.; Muff, Adam J.; Mundy, Michael B.; O'Brien, John K.; O'Brien, Kathryn M.; Ohmacht, Martin; Parker, Jeffrey J.; Poole, Ruth J.; Ratterman, Joseph D.; Salapura, Valentina; Satterfield, David L.; Senger, Robert M.; Smith, Brian; Steinmacher-Burow, Burkhard; Stockdell, William M.; Stunkel, Craig B.; Sugavanam, Krishnan; Sugawara, Yutaka; Takken, Todd E.; Trager, Barry M.; Van Oosten, James L.; Wait, Charles D.; Walkup, Robert E.; Watson, Alfred T.; Wisniewski, Robert W.; Wu, Peng

2015-07-14

A Multi-Petascale Highly Efficient Parallel Supercomputer of 100 petaOPS-scale computing, at decreased cost, power and footprint, and that allows for a maximum packaging density of processing nodes from an interconnect point of view. The Supercomputer exploits technological advances in VLSI that enables a computing model where many processors can be integrated into a single Application Specific Integrated Circuit (ASIC). Each ASIC computing node comprises a system-on-chip ASIC utilizing four or more processors integrated into one die, with each having full access to all system resources and enabling adaptive partitioning of the processors to functions such as compute or messaging I/O on an application by application basis, and preferably, enable adaptive partitioning of functions in accordance with various algorithmic phases within an application, or if I/O or other processors are underutilized, then can participate in computation or communication nodes are interconnected by a five dimensional torus network with DMA that optimally maximize the throughput of packet communications between nodes and minimize latency.

Hierarchical coordination control of mobile robots

NARCIS (Netherlands)

Adinandra, S.

2012-01-01

In the last decade, robotic systems have penetrated human life more than human can imagine. In particular, the multi-mobile robotic systems have faced a fast growing due to the fact that by deploying a large collection of mobile robots the overall system has a high redundancy and offers the

Parallel algorithm for dominant points correspondences in robot binocular stereo vision

Science.gov (United States)

Al-Tammami, A.; Singh, B.

1993-01-01

This paper presents an algorithm to find the correspondences of points representing dominant feature in robot stereo vision. The algorithm consists of two main steps: dominant point extraction and dominant point matching. In the feature extraction phase, the algorithm utilizes the widely used Moravec Interest Operator and two other operators: the Prewitt Operator and a new operator called Gradient Angle Variance Operator. The Interest Operator in the Moravec algorithm was used to exclude featureless areas and simple edges which are oriented in the vertical, horizontal, and two diagonals. It was incorrectly detecting points on edges which are not on the four main directions (vertical, horizontal, and two diagonals). The new algorithm uses the Prewitt operator to exclude featureless areas, so that the Interest Operator is applied only on the edges to exclude simple edges and to leave interesting points. This modification speeds-up the extraction process by approximately 5 times. The Gradient Angle Variance (GAV), an operator which calculates the variance of the gradient angle in a window around the point under concern, is then applied on the interesting points to exclude the redundant ones and leave the actual dominant ones. The matching phase is performed after the extraction of the dominant points in both stereo images. The matching starts with dominant points in the left image and does a local search, looking for corresponding dominant points in the right image. The search is geometrically constrained the epipolar line of the parallel-axes stereo geometry and the maximum disparity of the application environment. If one dominant point in the right image lies in the search areas, then it is the corresponding point of the reference dominant point in the left image. A parameter provided by the GAV is thresholded and used as a rough similarity measure to select the corresponding dominant point if there is more than one point the search area. The correlation is used as

Low Cost Multi-Sensor Robot Laser Scanning System and its Accuracy Investigations for Indoor Mapping Application

Science.gov (United States)

Chen, C.; Zou, X.; Tian, M.; Li, J.; Wu, W.; Song, Y.; Dai, W.; Yang, B.

2017-11-01

In order to solve the automation of 3D indoor mapping task, a low cost multi-sensor robot laser scanning system is proposed in this paper. The multiple-sensor robot laser scanning system includes a panorama camera, a laser scanner, and an inertial measurement unit and etc., which are calibrated and synchronized together to achieve simultaneously collection of 3D indoor data. Experiments are undertaken in a typical indoor scene and the data generated by the proposed system are compared with ground truth data collected by a TLS scanner showing an accuracy of 99.2% below 0.25 meter, which explains the applicability and precision of the system in indoor mapping applications.

Trajectory generation to suppress oscillations in under-constrained cable-driven parallel robots

Energy Technology Data Exchange (ETDEWEB)

Hwang, Sung Wook; Bak, Jeong Hyeon; Yoon, Jong Hyun; Park, Jong Hyeon [Dept. of Mechanical Engineering, Hanyang University, Seoul (Korea, Republic of); Park, Jong Oh [School of Mechanical Engineering, Chonnam National University, Gwangju (Korea, Republic of)

2016-12-15

Cable-driven parallel robots (CDPRs) have many advantages over conventional link-based robot manipulators in terms of acceleration due to their low inertia. This paper concerns about under-constrained CDPRs, which have a less number of cables than six, often used favorably due to their simpler structures. Since a smaller number of cables than 6 are employed, however, their payloads have extra degrees of motion freedom and exhibit swaying motions or oscillation. In this paper, a scheme to suppress unwanted oscillatory motions of the payload of a 4-cable-driven CDPR based on a Zero-vibration (ZV) input-shaping scheme is proposed. In this method, a motion in the 3-dimensional space is projected onto the independent motions on two vertical planes perpendicular to each other. On each of the vertical plane, the natural frequency of the CDPR is computed based on a 2-cable-driven planar CDPR model. The precise dynamic model of a planar CDPR is obtained in order to find the natural frequency, which depends on the payload position. The advantage of the proposed scheme is that it is possible to generate an oscillation-free trajectory based on a ZV input-shaping scheme despite the complexity in the dynamics of the CDPR and the difficulty in computing the natural frequencies of the CDPR, which is required in any ZV input-shaping scheme. To verify the effectiveness of the proposed method, a series of computer simulations and experiments were conducted for 3- dimensional motions with a 4-cable-driven CDPR. Their results showed that the motions of the CDPR with the proposed method exhibited a significant reduction in oscillations of the payload. However, when the payload moves near the edges of its workspace, the improvement in oscillation reduction diminished as expected due to the errors in model projection.

Multi-Robot Motion Planning: A Timed Automata Approach

OpenAIRE

Quottrup, Michael Melholt; Bak, Thomas; Izadi-Zamanabadi, Roozbeh

2004-01-01

This paper describes how a network of interacting timed automata can be used to model, analyze, and verify motion planning problems in a scenario with multiple robotic vehicles. The method presupposes an infra-structure of robots with feed-back controllers obeying simple restriction on a planar grid. The automata formalism merely presents a high-level model of environment, robots and control, but allows composition and formal symbolic reasoning about coordinated solutions. Composition is achi...

Intelligent computational control of multi-fingered dexterous robotic hand

OpenAIRE

Chen, Disi; Li, Gongfa; Jiang, Guozhang; Fang, Yinfeng; Ju, Zhaojie; Liu, Honghai

2015-01-01

We discuss the intelligent computational control theory and introduce the hardware structure of HIT/DLR II dexterous robotic hand, which is the typical dexterous robotic hand. We show that how DSP or FPGA controller can be used in the dexterous robotic hand. A popular intelligent dexterous robotic hand control system, which named Electromyography (EMG) control is investigated. We introduced some mathematical algorithms in EMG controlling, such as Gauss mixture model (GMM), artificial neural n...

Representation and shape estimation of Odin, a parallel under-actuated modular robot

DEFF Research Database (Denmark)

Lyder, Andreas; Petersen, Henrik Gordon; Støy, Kasper

2009-01-01

To understand the capabilities and behavior of a robot it is important to have knowledge about its physical structure and how its actuators control its shape. In this paper we analyze the kinematics and develop a general representation of a configuration of the heterogeneous modular robot Odin...... can be used to find the physical constraints of the Odin robot and estimate the shape of a configuration....

Optimization and Openmp Parallelization of a Discrete Element Code for Convex Polyhedra on Multi-Core Machines

Science.gov (United States)

Chen, Jian; Matuttis, Hans-Georg

2013-02-01

We report our experiences with the optimization and parallelization of a discrete element code for convex polyhedra on multi-core machines and introduce a novel variant of the sort-and-sweep neighborhood algorithm. While in theory the whole code in itself parallelizes ideally, in practice the results on different architectures with different compilers and performance measurement tools depend very much on the particle number and optimization of the code. After difficulties with the interpretation of the data for speedup and efficiency are overcome, respectable parallelization speedups could be obtained.

Parallel LC circuit model for multi-band absorption and preliminary design of radiative cooling.

Science.gov (United States)

Feng, Rui; Qiu, Jun; Liu, Linhua; Ding, Weiqiang; Chen, Lixue

2014-12-15

We perform a comprehensive analysis of multi-band absorption by exciting magnetic polaritons in the infrared region. According to the independent properties of the magnetic polaritons, we propose a parallel inductance and capacitance(PLC) circuit model to explain and predict the multi-band resonant absorption peaks, which is fully validated by using the multi-sized structure with identical dielectric spacing layer and the multilayer structure with the same strip width. More importantly, we present the application of the PLC circuit model to preliminarily design a radiative cooling structure realized by merging several close peaks together. This omnidirectional and polarization insensitive structure is a good candidate for radiative cooling application.

Multi-Robot Motion Planning: A Timed Automata Approach

DEFF Research Database (Denmark)

Quottrup, Michael Melholt; Bak, Thomas; Izadi-Zamanabadi, Roozbeh

2004-01-01

This paper describes how a network of interacting timed automata can be used to model, analyze, and verify motion planning problems in a scenario with multiple robotic vehicles. The method presupposes an infra-structure of robots with feed-back controllers obeying simple restriction on a planar...... grid. The automata formalism merely presents a high-level model of environment, robots and control, but allows composition and formal symbolic reasoning about coordinated solutions. Composition is achieved through synchronization, and the verification software UPPAAL is used for a symbolic verification...... then subsequently be used as a high-level motion plan for the robots. This paper reports on the timed automata framework, results of two verification experiments, promise of the approach, and gives a perspective for future research....

Multi-Robot Motion Planning: A Timed Automata Approach

DEFF Research Database (Denmark)

Quottrup, Michael Melholt; Bak, Thomas; Izadi-Zamanabadi, Roozbeh

This paper describes how a network of interacting timed automata can be used to model, analyze, and verify motion planning problems in a scenario with multiple robotic vehicles. The method presupposes an infra-structure of robots with feed-back controllers obeying simple restriction on a planar...... grid. The automata formalism merely presents a high-level model of environment, robots and control, but allows composition and formal symbolic reasoning about coordinated solutions. Composition is achieved through synchronization, and the verification software UPPAAL is used for a symbolic verification...... then subsequently be used as a high-level motion plan for the robots. This paper reports on the timed automata framework, results of two verification experiments, promise of the approach, and gives a perspective for future research....

The Effectiveness of Simulated Robots for Supporting the Learning of Introductory Programming: A Multi-Case Case Study

Science.gov (United States)

Major, Louis; Kyriacou, Theocharis; Brereton, Pearl

2014-01-01

This work investigates the effectiveness of simulated robots as tools to support the learning of programming. After the completion of a systematic review and exploratory research, a multi-case case study was undertaken. A simulator, named Kebot, was developed and used to run four 10-hour programming workshops. Twenty-three student participants…

Multi-Robot FastSLAM for Large Domains

Science.gov (United States)

2007-03-01

Derr, D. Fox, A.B. Cremers , Integrating global position estimation and position tracking for mobile robots: The dynamic markov localization approach...Intelligence (AAAI), 2000. 53. Andrew J. Davison and David W. Murray. Simultaneous Localization and Map- Building Using Active Vision. IEEE...Wyeth, Michael Milford and David Prasser. A Modified Particle Filter for Simultaneous Robot Localization and Landmark Tracking in an Indoor

A Human–Robot Interaction Perspective on Assistive and Rehabilitation Robotics

Directory of Open Access Journals (Sweden)

Philipp Beckerle

2017-05-01

Full Text Available Assistive and rehabilitation devices are a promising and challenging field of recent robotics research. Motivated by societal needs such as aging populations, such devices can support motor functionality and subject training. The design, control, sensing, and assessment of the devices become more sophisticated due to a human in the loop. This paper gives a human–robot interaction perspective on current issues and opportunities in the field. On the topic of control and machine learning, approaches that support but do not distract subjects are reviewed. Options to provide sensory user feedback that are currently missing from robotic devices are outlined. Parallels between device acceptance and affective computing are made. Furthermore, requirements for functional assessment protocols that relate to real-world tasks are discussed. In all topic areas, the design of human-oriented frameworks and methods is dominated by challenges related to the close interaction between the human and robotic device. This paper discusses the aforementioned aspects in order to open up new perspectives for future robotic solutions.

A Human–Robot Interaction Perspective on Assistive and Rehabilitation Robotics

Science.gov (United States)

Beckerle, Philipp; Salvietti, Gionata; Unal, Ramazan; Prattichizzo, Domenico; Rossi, Simone; Castellini, Claudio; Hirche, Sandra; Endo, Satoshi; Amor, Heni Ben; Ciocarlie, Matei; Mastrogiovanni, Fulvio; Argall, Brenna D.; Bianchi, Matteo

2017-01-01

Assistive and rehabilitation devices are a promising and challenging field of recent robotics research. Motivated by societal needs such as aging populations, such devices can support motor functionality and subject training. The design, control, sensing, and assessment of the devices become more sophisticated due to a human in the loop. This paper gives a human–robot interaction perspective on current issues and opportunities in the field. On the topic of control and machine learning, approaches that support but do not distract subjects are reviewed. Options to provide sensory user feedback that are currently missing from robotic devices are outlined. Parallels between device acceptance and affective computing are made. Furthermore, requirements for functional assessment protocols that relate to real-world tasks are discussed. In all topic areas, the design of human-oriented frameworks and methods is dominated by challenges related to the close interaction between the human and robotic device. This paper discusses the aforementioned aspects in order to open up new perspectives for future robotic solutions. PMID:28588473

International Conference on Intelligent Robots and Systems - IROS 2011

CERN Document Server

Rosen, Jacob; Redundancy in Robot Manipulators and Multi-Robot Systems

2013-01-01

The trend in the evolution of robotic systems is that the number of degrees of freedom increases. This is visible both in robot manipulator design and in the shift of focus from single to multi-robot systems. Following the principles of evolution in nature, one may infer that adding degrees of freedom to robot systems design is beneficial. However, since nature did not select snake-like bodies for all creatures, it is reasonable to expect the presence of a certain selection pressure on the number of degrees of freedom. Thus, understanding costs and benefits of multiple degrees of freedom, especially those that create redundancy, is a fundamental problem in the field of robotics. This volume is mostly based on the works presented at the workshop on Redundancy in Robot Manipulators and Multi-Robot Systems at the IEEE/RSJ International Conference on Intelligent Robots and Systems - IROS 2011. The workshopwas envisioned as a dialog between researchers from two separate, but obviously relatedfields of robotics: on...

A Model of Parallel Kinematics for Machine Calibration

DEFF Research Database (Denmark)

Pedersen, David Bue; Bæk Nielsen, Morten; Kløve Christensen, Simon

2016-01-01

Parallel kinematics have been adopted by more than 25 manufacturers of high-end desktop 3D printers [Wohlers Report (2015), p.118] as well as by research projects such as the WASP project [WASP (2015)], a 12 meter tall linear delta robot for Additive Manufacture of large-scale components for cons......Parallel kinematics have been adopted by more than 25 manufacturers of high-end desktop 3D printers [Wohlers Report (2015), p.118] as well as by research projects such as the WASP project [WASP (2015)], a 12 meter tall linear delta robot for Additive Manufacture of large-scale components...

Multi-objective based on parallel vector evaluated particle swarm optimization for optimal steady-state performance of power systems

DEFF Research Database (Denmark)

Vlachogiannis, Ioannis (John); Lee, K Y

2009-01-01

In this paper the state-of-the-art extended particle swarm optimization (PSO) methods for solving multi-objective optimization problems are represented. We emphasize in those, the co-evolution technique of the parallel vector evaluated PSO (VEPSO), analysed and applied in a multi-objective problem...

Soft computing in advanced robotics

CERN Document Server

Kobayashi, Ichiro; Kim, Euntai

2014-01-01

Intelligent system and robotics are inevitably bound up; intelligent robots makes embodiment of system integration by using the intelligent systems. We can figure out that intelligent systems are to cell units, while intelligent robots are to body components. The two technologies have been synchronized in progress. Making leverage of the robotics and intelligent systems, applications cover boundlessly the range from our daily life to space station; manufacturing, healthcare, environment, energy, education, personal assistance, logistics. This book aims at presenting the research results in relevance with intelligent robotics technology. We propose to researchers and practitioners some methods to advance the intelligent systems and apply them to advanced robotics technology. This book consists of 10 contributions that feature mobile robots, robot emotion, electric power steering, multi-agent, fuzzy visual navigation, adaptive network-based fuzzy inference system, swarm EKF localization and inspection robot. Th...

Incorporating social benefits in multi-objective optimization of forest-based bioenergy and biofuel supply chains

International Nuclear Information System (INIS)

Cambero, Claudia; Sowlati, Taraneh

2016-01-01

Highlights: • Quantified social benefits of forest- based biomass supply chain. • Developed multi-objective optimization model. • Incorporated social benefits into multi-objective model. • Solved the model using the AUGMECON method. • Applied the model to a case study in Canada. - Abstract: Utilization of forest and wood residues to produce bioenergy and biofuels could generate additional revenue streams for forestry companies, reduce their environmental impacts and generate new development opportunities for forest-dependent communities. Further development of forest-based biorefineries entails addressing complexities and challenges related to biomass procurement, logistics, technologies, and sustainability. Numerous optimization models have been proposed for the economic and environmental design of biomass-to-bioenergy or biofuel supply chains. A few of them also maximized the job creation potential of the supply chain through the use of employment multipliers. The use of a total job creation indicator as the social optimization objective implies that all new jobs generate the same level of social benefit. In this paper, we quantify the potential social benefit of new forest-based biorefinery supply chains considering different impacts of new jobs based on their type and location. This social benefit is incorporated into a multi-objective mixed integer linear programming model that maximizes the social benefit, net present value and greenhouse gas emission saving potential of a forest-based biorefinery supply chain. The applicability of the model is illustrated through a case study in the interior region of British Columbia, Canada where different utilization paths for available forest and wood residues are investigated. The multi-objective optimization model is solved using a Pareto-generating method. The analysis of the generated set of Pareto-optimal solutions show a trade-off between the net present value of the supply chain and the other two

Design Sliding Mode Controller of with Parallel Fuzzy Inference System Compensator to Control of Robot Manipulator

Directory of Open Access Journals (Sweden)

Farzin Piltan

2013-06-01

Full Text Available Sliding mode controller (SMC is a significant nonlinear controller under condition of partly uncertain dynamic parameters of system. This controller is used to control of highly nonlinear systems especially for robot manipulators, because this controller is a robust and stable. Conversely, pure sliding mode controller is used in many applications; it has two important drawbacks namely; chattering phenomenon, and nonlinear equivalent dynamic formulation in uncertain dynamic parameter. The nonlinear equivalent dynamic formulation problem and chattering phenomenon in uncertain system can be solved by using artificial intelligence theorem. However fuzzy logic controller is used to control complicated nonlinear dynamic systems, but it cannot guarantee stability and robustness.  In this research parallel fuzzy logic theory is used to compensate the system dynamic uncertainty.

Towards Optimal Platform-Based Robot Design for Ankle Rehabilitation: The State of the Art and Future Prospects

Directory of Open Access Journals (Sweden)

Qing Miao

2018-01-01

Full Text Available This review aims to compare existing robot-assisted ankle rehabilitation techniques in terms of robot design. Included studies mainly consist of selected papers in two published reviews involving a variety of robot-assisted ankle rehabilitation techniques. A free search was also made in Google Scholar and Scopus by using keywords “ankle∗,” and “robot∗,” and (“rehabilitat∗” or “treat∗”. The search is limited to English-language articles published between January 1980 and September 2016. Results show that existing robot-assisted ankle rehabilitation techniques can be classified into wearable exoskeleton and platform-based devices. Platform-based devices are mostly developed for the treatment of a variety of ankle musculoskeletal and neurological injuries, while wearable ones focus more on ankle-related gait training. In terms of robot design, comparative analysis indicates that an ideal ankle rehabilitation robot should have aligned rotation center as the ankle joint, appropriate workspace, and actuation torque, no matter how many degrees of freedom (DOFs it has. Single-DOF ankle robots are mostly developed for specific applications, while multi-DOF devices are more suitable for comprehensive ankle rehabilitation exercises. Other factors including posture adjustability and sensing functions should also be considered to promote related clinical applications. An ankle rehabilitation robot with reconfigurability to maximize its functions will be a new research point towards optimal design, especially on parallel mechanisms.

Modelling Engagement in Multi-Party Conversations : Data-Driven Approaches to Understanding Human-Human Communication Patterns for Use in Human-Robot Interactions

OpenAIRE

Oertel, Catharine

2016-01-01

The aim of this thesis is to study human-human interaction in order to provide virtual agents and robots with the capability to engage into multi-party-conversations in a human-like-manner. The focus lies with the modelling of conversational dynamics and the appropriate realization of multi-modal feedback behaviour. For such an undertaking, it is important to understand how human-human communication unfolds in varying contexts and constellations over time. To this end, multi-modal human-human...

Robotics for nuclear power plants

International Nuclear Information System (INIS)

Nakayama, Ryoichi; Kimura, Motohiko; Abe, Akira

1993-01-01

A continuing need exists for automatic or remote-controlled machines or robots which can perform inspection and maintenance tasks in nuclear power plants. Toshiba has developed several types of monofunctional and multi- functional robots for such purposes over the past 20 years, some of which have already been used in actual plants. This paper describes new multifunctional robots for inspection and maintenance. An inspection robot has been applied in an actual plant for two years for performance testing. Maintenance robots for grinding tasks have also been developed, which can be easily teleoperated by the operator using automatic control. These new robots are expected to be applied to actual inspection and maintenance work in nuclear power plants. (author)

Parallel Programming with Intel Parallel Studio XE

CERN Document Server

Blair-Chappell , Stephen

2012-01-01

Optimize code for multi-core processors with Intel's Parallel Studio Parallel programming is rapidly becoming a "must-know" skill for developers. Yet, where to start? This teach-yourself tutorial is an ideal starting point for developers who already know Windows C and C++ and are eager to add parallelism to their code. With a focus on applying tools, techniques, and language extensions to implement parallelism, this essential resource teaches you how to write programs for multicore and leverage the power of multicore in your programs. Sharing hands-on case studies and real-world examples, the

Structural brain changes after traditional and robot-assisted multi-domain cognitive training in community-dwelling healthy elderly.

Directory of Open Access Journals (Sweden)

Geon Ha Kim

Full Text Available The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.ClnicalTrials.gov NCT01596205.

Dimensional synthesis of a 3-DOF parallel manipulator with full circle rotation

Science.gov (United States)

Ni, Yanbing; Wu, Nan; Zhong, Xueyong; Zhang, Biao

2015-07-01

Parallel robots are widely used in the academic and industrial fields. In spite of the numerous achievements in the design and dimensional synthesis of the low-mobility parallel robots, few research efforts are directed towards the asymmetric 3-DOF parallel robots whose end-effector can realize 2 translational and 1 rotational(2T1R) motion. In order to develop a manipulator with the capability of full circle rotation to enlarge the workspace, a new 2T1R parallel mechanism is proposed. The modeling approach and kinematic analysis of this proposed mechanism are investigated. Using the method of vector analysis, the inverse kinematic equations are established. This is followed by a vigorous proof that this mechanism attains an annular workspace through its circular rotation and 2 dimensional translations. Taking the first order perturbation of the kinematic equations, the error Jacobian matrix which represents the mapping relationship between the error sources of geometric parameters and the end-effector position errors is derived. With consideration of the constraint conditions of pressure angles and feasible workspace, the dimensional synthesis is conducted with a goal to minimize the global comprehensive performance index. The dimension parameters making the mechanism to have optimal error mapping and kinematic performance are obtained through the optimization algorithm. All these research achievements lay the foundation for the prototype building of such kind of parallel robots.

'Filigree Robotics'

DEFF Research Database (Denmark)

2016-01-01

-scale 3D printed ceramics accompanied by prints, videos and ceramic probes, which introduce the material and design processes of the project.'Filigree Robotics' experiments with a combination of the traditional ceramic technique of ‘Overforming’ with 3d Laserscan and Robotic extrusion technique...... application of reflectivity after an initial 3d print. The consideration and integration of this material practice into a digital workflow took place in an interdisciplinary collaboration of Ceramicist Flemming Tvede Hansen from KADK Superformlab and architectural researchers from CITA (Martin Tamke, Henrik...... to the creation of the form and invites for experimentation. In Filigree Robotics we combine the crafting of the mold with a parallel running generative algorithm, which is fed by a constant laserscan of the 3d surface. This algorithm, analyses the topology of the mold, identifies high and low points and uses...

Interoperability of Standards for Robotics in CIME

DEFF Research Database (Denmark)

Sørensen, Torben

1996-01-01

geometry, kinematics, robotics, dynamics, and control, hence on a coherent neutral information model of the process chain from design to manufacturing. The second main goal was to increase the accuracy of off-line programmed robots. The results were demonstrated in industrial applications....

Developing a multi-joint upper limb exoskeleton robot for diagnosis, therapy, and outcome evaluation in neurorehabilitation.

Science.gov (United States)

Ren, Yupeng; Kang, Sang Hoon; Park, Hyung-Soon; Wu, Yi-Ning; Zhang, Li-Qun

2013-05-01

Arm impairments in patients post stroke involve the shoulder, elbow and wrist simultaneously. It is not very clear how patients develop spasticity and reduced range of motion (ROM) at the multiple joints and the abnormal couplings among the multiple joints and the multiple degrees-of-freedom (DOF) during passive movement. It is also not clear how they lose independent control of individual joints/DOFs and coordination among the joints/DOFs during voluntary movement. An upper limb exoskeleton robot, the IntelliArm, which can control the shoulder, elbow, and wrist, was developed, aiming to support clinicians and patients with the following integrated capabilities: 1) quantitative, objective, and comprehensive multi-joint neuromechanical pre-evaluation capabilities aiding multi-joint/DOF diagnosis for individual patients; 2) strenuous and safe passive stretching of hypertonic/deformed arm for loosening up muscles/joints based on the robot-aided diagnosis; 3) (assistive/resistive) active reaching training after passive stretching for regaining/improving motor control ability; and 4) quantitative, objective, and comprehensive neuromechanical outcome evaluation at the level of individual joints/DOFs, multiple joints, and whole arm. Feasibility of the integrated capabilities was demonstrated through experiments with stroke survivors and healthy subjects.

Autonomous Motion Learning for Intra-Vehicular Activity Space Robot

Science.gov (United States)

Watanabe, Yutaka; Yairi, Takehisa; Machida, Kazuo

Space robots will be needed in the future space missions. So far, many types of space robots have been developed, but in particular, Intra-Vehicular Activity (IVA) space robots that support human activities should be developed to reduce human-risks in space. In this paper, we study the motion learning method of an IVA space robot with the multi-link mechanism. The advantage point is that this space robot moves using reaction force of the multi-link mechanism and contact forces from the wall as space walking of an astronaut, not to use a propulsion. The control approach is determined based on a reinforcement learning with the actor-critic algorithm. We demonstrate to clear effectiveness of this approach using a 5-link space robot model by simulation. First, we simulate that a space robot learn the motion control including contact phase in two dimensional case. Next, we simulate that a space robot learn the motion control changing base attitude in three dimensional case.

Detecting the multi-spin interaction of an XY spin chain by the geometric phase of a coupled qubit

International Nuclear Information System (INIS)

Zhang, Xiu-xing; Zhang, Ai-ping; Li, Fu-li

2012-01-01

We investigate geometric phase (GP) of a qubit symmetrically coupled to a XY spin chain with three-spin interaction in a transverse magnetic field. An analytical expression for the GP is found in the weak coupling limit. It is shown that the GP displays a sharp peak or dip around the quantum phase transition point of the spin chain. Without the three-spin interaction, the GP has a peak or dip around the critical point λ=1. If the three-spin interaction exists, the peak or dip position is obviously shifted away from the original position. This result reveals that the GP may be taken as an observable to detect both the existence and strength of multi-spin interaction in a spin chain. -- Highlights: ► Analytical expression for geometric phase (GP) of a qubit coupled to a spin chain is obtained. ► Relation between GP and multi-spin interaction is investigated. ► Detection of multi-spin interaction by means of GP is proposed.

HyPro: A Multi-DoF Hybrid-Powered Transradial Robotic Prosthesis

Directory of Open Access Journals (Sweden)

C. L. Semasinghe

2018-01-01

Full Text Available This paper proposes a multi-DoF hybrid-powered transradial robotic prosthesis, named HyPro. The HyPro consists of two prosthetic units: hand and wrist that can achieve five grasping patterns such as power grasp, tip grasp, lateral grasp, hook grasp, and index point. It is an underactuated device with 15 degrees of freedom. A hybrid powering concept is proposed and implemented on hand unit of HyPro where the key focus is on restoration of grasp functions of biological hand. A novel underactuated mechanism is introduced to achieve the required hand preshaping for a given grasping pattern using electric power in the pregrasp stage and body power is used in grasp stage to execute the final grasping action with the selected fingers. Unlike existing hybrid prostheses where each of the joints is separately controlled by either electric or body power, the proposed prosthesis is capable of delivering grasping power in combination. The wrist unit of HyPro is designed and developed to achieve flexion-extension and supination-pronation using electric power. Experiments were carried out to evaluate the functionality and performance of the proposed hybrid-powered robotic prosthesis. The results verified the potential of HyPro to perform intended grasping patterns effectively and efficiently.

A multi-objective particle swarm optimization for production-distribution planning in supply chain network

Directory of Open Access Journals (Sweden)

Alireza Pourrousta

2012-04-01

Full Text Available Integrated supply chain includes different components of order, production and distribution and it plays an important role on reducing the cost of manufacturing system. In this paper, an integrated supply chain in a form of multi-objective decision-making problem is presented. The proposed model of this paper considers different parameters with uncertainty using trapezoid numbers. We first implement a ranking method to covert the fuzzy model into a crisp one and using multi-objective particle swarm optimization, we solve the resulted model. The results are compared with the performance of NSGA-II for some randomly generated problems and the preliminary results indicate that the proposed model of the paper performs better than the alternative method.

A parallel solution-adaptive scheme for predicting multi-phase core flows in solid propellant rocket motors

International Nuclear Information System (INIS)

Sachdev, J.S.; Groth, C.P.T.; Gottlieb, J.J.

2003-01-01

The development of a parallel adaptive mesh refinement (AMR) scheme is described for solving the governing equations for multi-phase (gas-particle) core flows in solid propellant rocket motors (SRM). An Eulerian formulation is used to described the coupled motion between the gas and particle phases. A cell-centred upwind finite-volume discretization and the use of limited solution reconstruction, Riemann solver based flux functions for the gas and particle phases, and explicit multi-stage time-stepping allows for high solution accuracy and computational robustness. A Riemann problem is formulated for prescribing boundary data at the burning surface. Efficient and scalable parallel implementations are achieved with domain decomposition on distributed memory multiprocessor architectures. Numerical results are described to demonstrate the capabilities of the approach for predicting SRM core flows. (author)

Intelligent controller of a flexible hybrid robot machine for ITER assembly and maintenance

International Nuclear Information System (INIS)

Al-saedi, Mazin I.; Wu, Huapeng; Handroos, Heikki

2014-01-01

Highlights: • Studying flexible multibody dynamic of hybrid parallel robot. • Investigating fuzzy-PD controller to control a hybrid flexible hydraulically driven robot. • Investigating ANFIS-PD controller to control a hybrid flexible robot. Compare to traditional PID this method gives better performance. • Using the equilibrium of reaction forces between the parallel and serial parts of hybrid robot to control the serial part hydraulically driven. - Abstract: The assembly and maintenance of International Thermonuclear Experimental Reactor (ITER) vacuum vessel (VV) is highly challenging since the tasks performed by the robot involve welding, material handling, and machine cutting from inside the VV. To fulfill the tasks in ITER application, this paper presents a hybrid redundant manipulator with four DOFs provided by serial kinematic axes and six DOFs by parallel mechanism. Thus, in machining, to achieve greater end-effector trajectory tracking accuracy for surface quality, a robust control of the actuators for the flexible link has to be deduced. In this paper, the intelligent control of a hydraulically driven parallel robot part based on the dynamic model and two control schemes have been investigated: (1) fuzzy-PID self tuning controller composed of the conventional PID control and with fuzzy logic; (2) adaptive neuro-fuzzy inference system-PID (ANFIS-PID) self tuning of the gains of the PID controller, which are implemented independently to control each hydraulic cylinder of the parallel robot based on rod position predictions. The obtained results of the fuzzy-PID and ANFIS-PID self tuning controller can reduce more tracking errors than the conventional PID controller. Subsequently, the serial component of the hybrid robot can be analyzed using the equilibrium of reaction forces at the universal joint connections of the hexa-element. To achieve precise positional control of the end effector for maximum precision machining, the hydraulic cylinder should

Intelligent controller of a flexible hybrid robot machine for ITER assembly and maintenance

Energy Technology Data Exchange (ETDEWEB)

Al-saedi, Mazin I., E-mail: mazin.al-saedi@lut.fi; Wu, Huapeng; Handroos, Heikki

2014-10-15

Highlights: • Studying flexible multibody dynamic of hybrid parallel robot. • Investigating fuzzy-PD controller to control a hybrid flexible hydraulically driven robot. • Investigating ANFIS-PD controller to control a hybrid flexible robot. Compare to traditional PID this method gives better performance. • Using the equilibrium of reaction forces between the parallel and serial parts of hybrid robot to control the serial part hydraulically driven. - Abstract: The assembly and maintenance of International Thermonuclear Experimental Reactor (ITER) vacuum vessel (VV) is highly challenging since the tasks performed by the robot involve welding, material handling, and machine cutting from inside the VV. To fulfill the tasks in ITER application, this paper presents a hybrid redundant manipulator with four DOFs provided by serial kinematic axes and six DOFs by parallel mechanism. Thus, in machining, to achieve greater end-effector trajectory tracking accuracy for surface quality, a robust control of the actuators for the flexible link has to be deduced. In this paper, the intelligent control of a hydraulically driven parallel robot part based on the dynamic model and two control schemes have been investigated: (1) fuzzy-PID self tuning controller composed of the conventional PID control and with fuzzy logic; (2) adaptive neuro-fuzzy inference system-PID (ANFIS-PID) self tuning of the gains of the PID controller, which are implemented independently to control each hydraulic cylinder of the parallel robot based on rod position predictions. The obtained results of the fuzzy-PID and ANFIS-PID self tuning controller can reduce more tracking errors than the conventional PID controller. Subsequently, the serial component of the hybrid robot can be analyzed using the equilibrium of reaction forces at the universal joint connections of the hexa-element. To achieve precise positional control of the end effector for maximum precision machining, the hydraulic cylinder should

3D YAG laser cutting robot. 3 jigen YAG laser setsudan robot

Energy Technology Data Exchange (ETDEWEB)

Mukai, Y. (Matsushita Electric Industrial Co. Ltd., Osaka (Japan))

1991-11-01

The present status was introduced of three-dimensional processing by the YAG laser multi-articulation robot to introduce the focusing system. The lowering in locus accuracy of multi-articulation robot is caused by the accuracy and time of computation to interpolate the locus, response characteristics of servo system, and calibration problem of mechanical/structural system. Also as low in output power of laser, it has problem in focusing the energy in the radiating optical system. A focusing system, high in response velocity, is necessary in the processor to use the optical fiber in the optical transfer system. As processing and measuring at an identical spot, the present system can integrate the detection use electrode and nozzle so as to use an electrostatic capacity type sensor, high in response frequency. To avoid the interference with jig, etc., the nozzle of radiating unit was integrated with the detection use electrode so that development was made of height sensor, capable of executing the three-dimensional processing. The present robot is characterized by a standardized equipment of control system with a sliding shaft, independent of the operational shaft properly of robot in order to be exclusively used for the focusing. 9 figs.

Weighing Efficiency-Robustness in Supply Chain Disruption by Multi-Objective Firefly Algorithm

Directory of Open Access Journals (Sweden)

Tong Shu

2016-03-01

Full Text Available This paper investigates various supply chain disruptions in terms of scenario planning, including node disruption and chain disruption; namely, disruptions in distribution centers and disruptions between manufacturing centers and distribution centers. Meanwhile, it also focuses on the simultaneous disruption on one node or a number of nodes, simultaneous disruption in one chain or a number of chains and the corresponding mathematical models and exemplification in relation to numerous manufacturing centers and diverse products. Robustness of the design of the supply chain network is examined by weighing efficiency against robustness during supply chain disruptions. Efficiency is represented by operating cost; robustness is indicated by the expected disruption cost and the weighing issue is calculated by the multi-objective firefly algorithm for consistency in the results. It has been shown that the total cost achieved by the optimal target function is lower than that at the most effective time of supply chains. In other words, the decrease of expected disruption cost by improving robustness in supply chains is greater than the increase of operating cost by reducing efficiency, thus leading to cost advantage. Consequently, by approximating the Pareto Front Chart of weighing between efficiency and robustness, enterprises can choose appropriate efficiency and robustness for their longer-term development.

Optimal Golomb Ruler Sequences Generation for Optical WDM Systems: A Novel Parallel Hybrid Multi-objective Bat Algorithm

Science.gov (United States)

Bansal, Shonak; Singh, Arun Kumar; Gupta, Neena

2017-02-01

In real-life, multi-objective engineering design problems are very tough and time consuming optimization problems due to their high degree of nonlinearities, complexities and inhomogeneity. Nature-inspired based multi-objective optimization algorithms are now becoming popular for solving multi-objective engineering design problems. This paper proposes original multi-objective Bat algorithm (MOBA) and its extended form, namely, novel parallel hybrid multi-objective Bat algorithm (PHMOBA) to generate shortest length Golomb ruler called optimal Golomb ruler (OGR) sequences at a reasonable computation time. The OGRs found their application in optical wavelength division multiplexing (WDM) systems as channel-allocation algorithm to reduce the four-wave mixing (FWM) crosstalk. The performances of both the proposed algorithms to generate OGRs as optical WDM channel-allocation is compared with other existing classical computing and nature-inspired algorithms, including extended quadratic congruence (EQC), search algorithm (SA), genetic algorithms (GAs), biogeography based optimization (BBO) and big bang-big crunch (BB-BC) optimization algorithms. Simulations conclude that the proposed parallel hybrid multi-objective Bat algorithm works efficiently as compared to original multi-objective Bat algorithm and other existing algorithms to generate OGRs for optical WDM systems. The algorithm PHMOBA to generate OGRs, has higher convergence and success rate than original MOBA. The efficiency improvement of proposed PHMOBA to generate OGRs up to 20-marks, in terms of ruler length and total optical channel bandwidth (TBW) is 100 %, whereas for original MOBA is 85 %. Finally the implications for further research are also discussed.

Forward kinematics solutions of a special six-degree-of-freedom parallel manipulator with three limbs

Directory of Open Access Journals (Sweden)

Jianxun Fu

2015-05-01

Full Text Available This article presents a special 6-degree-of freedom parallel manipulator, and the mechanical structure of this robot has been introduced; with this structure, the kinematic constrain equations are decoupled. Based on this character, the polynomial solutions of the forward kinematics problem are also presented. In this method, the closed-loop kinematic chain of the manipulator is divided into two parts, the solution forward position kinematics is obtained by a first-degree polynomial equation first, and then an eighth-degree polynomial equation in a single variable for the forward orientation kinematics is obtained. Based on those solutions, the configurations of the robot, including position and orientation of the end-effector, are graphically displayed. A numerical simulation is given to verify the algorithm, and the result implies that for a given set of input values, the manipulator can be assembled in eight different configurations at most. And a set of experiments illustrate the motion ability for forward kinematics of the prototype of this manipulator.

On the multi-level solution algorithm for Markov chains

Energy Technology Data Exchange (ETDEWEB)

Horton, G. [Univ. of Erlangen, Nuernberg (Germany)

1996-12-31

We discuss the recently introduced multi-level algorithm for the steady-state solution of Markov chains. The method is based on the aggregation principle, which is well established in the literature. Recursive application of the aggregation yields a multi-level method which has been shown experimentally to give results significantly faster than the methods currently in use. The algorithm can be reformulated as an algebraic multigrid scheme of Galerkin-full approximation type. The uniqueness of the scheme stems from its solution-dependent prolongation operator which permits significant computational savings in the evaluation of certain terms. This paper describes the modeling of computer systems to derive information on performance, measured typically as job throughput or component utilization, and availability, defined as the proportion of time a system is able to perform a certain function in the presence of component failures and possibly also repairs.

Morphology Independent Learning in Modular Robots

DEFF Research Database (Denmark)

Christensen, David Johan; Bordignon, Mirko; Schultz, Ulrik Pagh

2009-01-01

Hand-coding locomotion controllers for modular robots is difficult due to their polymorphic nature. Instead, we propose to use a simple and distributed reinforcement learning strategy. ATRON modules with identical controllers can be assembled in any configuration. To optimize the robot’s locomotion...... speed its modules independently and in parallel adjust their behavior based on a single global reward signal. In simulation, we study the learning strategy’s performance on different robot configurations. On the physical platform, we perform learning experiments with ATRON robots learning to move as fast...

Fable: Design of a Modular Robotic Playware Platform

DEFF Research Database (Denmark)

Pacheco, Moises; Moghadam, Mikael; Magnússon, Arnþór

2013-01-01

-based system composed of reconfigurable heterogeneous modules with a reliable and scalable connector. Furthermore, this paper describes tests where the connector design is tested with children, and presents examples of a moving snake and a quadruped robot, as well as an interactive upper humanoid torso.......We are developing the Fable modular robotic system as a playware platform that will enable non-expert users to develop robots ranging from advanced robotic toys to robotic solutions to problems encountered in their daily lives. This paper presents the mechanical design of Fable: a chain...

Coherent transport in a system of periodic linear chain of quantum dots situated between two parallel quantum wires

International Nuclear Information System (INIS)

Petrosyan, Lyudvig S

2016-01-01

We study coherent transport in a system of periodic linear chain of quantum dots situated between two parallel quantum wires. We show that the resonant-tunneling conductance between the wires exhibits a Rabi splitting of the resonance peak as a function of Fermi energy in the wires. This effect is an electron transport analogue of the Rabi splitting in optical spectra of two interacting systems. The conductance peak splitting originates from the anticrossing of Bloch bands in a periodic system that is caused by a strong coupling between the electron states in the quantum dot chain and quantum wires. (paper)

Intelligent robotic tracker

Science.gov (United States)

Otaguro, W. S.; Kesler, L. O.; Land, K. C.; Rhoades, D. E.

1987-01-01

An intelligent tracker capable of robotic applications requiring guidance and control of platforms, robotic arms, and end effectors has been developed. This packaged system capable of supervised autonomous robotic functions is partitioned into a multiple processor/parallel processing configuration. The system currently interfaces to cameras but has the capability to also use three-dimensional inputs from scanning laser rangers. The inputs are fed into an image processing and tracking section where the camera inputs are conditioned for the multiple tracker algorithms. An executive section monitors the image processing and tracker outputs and performs all the control and decision processes. The present architecture of the system is presented with discussion of its evolutionary growth for space applications. An autonomous rendezvous demonstration of this system was performed last year. More realistic demonstrations in planning are discussed.

Advanced real-time multi-display educational system (ARMES): An innovative real-time audiovisual mentoring tool for complex robotic surgery.

Science.gov (United States)

Lee, Joong Ho; Tanaka, Eiji; Woo, Yanghee; Ali, Güner; Son, Taeil; Kim, Hyoung-Il; Hyung, Woo Jin

2017-12-01

The recent scientific and technologic advances have profoundly affected the training of surgeons worldwide. We describe a novel intraoperative real-time training module, the Advanced Robotic Multi-display Educational System (ARMES). We created a real-time training module, which can provide a standardized step by step guidance to robotic distal subtotal gastrectomy with D2 lymphadenectomy procedures, ARMES. The short video clips of 20 key steps in the standardized procedure for robotic gastrectomy were created and integrated with TilePro™ software to delivery on da Vinci Surgical Systems (Intuitive Surgical, Sunnyvale, CA). We successfully performed the robotic distal subtotal gastrectomy with D2 lymphadenectomy for patient with gastric cancer employing this new teaching method without any transfer errors or system failures. Using this technique, the total operative time was 197 min and blood loss was 50 mL and there were no intra- or post-operative complications. Our innovative real-time mentoring module, ARMES, enables standardized, systematic guidance during surgical procedures. © 2017 Wiley Periodicals, Inc.

Robust exponential stabilization of nonholonomic wheeled mobile robots with unknown visual parameters

Institute of Scientific and Technical Information of China (English)

无

2011-01-01

The visual servoing stabilization of nonholonomic mobile robot with unknown camera parameters is investigated.A new kind of uncertain chained model of nonholonomic kinemetic system is obtained based on the visual feedback and the standard chained form of type (1,2) mobile robot.Then,a novel time-varying feedback controller is proposed for exponentially stabilizing the position and orientation of the robot using visual feedback and switching strategy when the camera parameters are not known.The exponential s...

Multi Scale Finite Element Analyses By Using SEM-EBSD Crystallographic Modeling and Parallel Computing

International Nuclear Information System (INIS)

Nakamachi, Eiji

2005-01-01

A crystallographic homogenization procedure is introduced to the conventional static-explicit and dynamic-explicit finite element formulation to develop a multi scale - double scale - analysis code to predict the plastic strain induced texture evolution, yield loci and formability of sheet metal. The double-scale structure consists of a crystal aggregation - micro-structure - and a macroscopic elastic plastic continuum. At first, we measure crystal morphologies by using SEM-EBSD apparatus, and define a unit cell of micro structure, which satisfy the periodicity condition in the real scale of polycrystal. Next, this crystallographic homogenization FE code is applied to 3N pure-iron and 'Benchmark' aluminum A6022 polycrystal sheets. It reveals that the initial crystal orientation distribution - the texture - affects very much to a plastic strain induced texture and anisotropic hardening evolutions and sheet deformation. Since, the multi-scale finite element analysis requires a large computation time, a parallel computing technique by using PC cluster is developed for a quick calculation. In this parallelization scheme, a dynamic workload balancing technique is introduced for quick and efficient calculations

Microstructure and mechanical properties of AZ91 tubes fabricated by Multi-pass Parallel Tubular Channel Angular Pressing

OpenAIRE

Hooman Abdolvand; Ghader Faraji; Javad Shahbazi Karami

2017-01-01

Parallel Tubular Channel Angular Pressing (PTCAP) process is a novel recently developed severe plastic deformation (SPD) method for producing ultrafine grained (UFG) and nanograined (NG) tubular specimens with excellent mechanical and physical properties. This process has several advantageous compared to its TCAP counterparts. In this paper, a fine grained AZ91 tube was fabricated via multi pass parallel tubular channel angular pressing (PTCAP) process. Tubes were processed up to three passes...

Massively Parallel Sort-Merge Joins in Main Memory Multi-Core Database Systems

OpenAIRE

Martina-Cezara Albutiu, Alfons Kemper, Thomas Neumann

2012-01-01

Two emerging hardware trends will dominate the database system technology in the near future: increasing main memory capacities of several TB per server and massively parallel multi-core processing. Many algorithmic and control techniques in current database technology were devised for disk-based systems where I/O dominated the performance. In this work we take a new look at the well-known sort-merge join which, so far, has not been in the focus of research ...

Critical chain construction with multi-resource constraints based on portfolio technology in South-to-North Water Diversion Project

Directory of Open Access Journals (Sweden)

Jing-chun Feng

2011-06-01

Full Text Available Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the system analysis theory and project portfolio theory, this paper discusses the creation of project portfolios based on the similarity principle and gives the definition of priority in multi-resource allocation based on quantitative analysis. A model with multi-resource constraints, which can be applied to the critical chain construction of the A-bid section in the South-to-North Water Diversion Project, was proposed. Contrast analysis with the comprehensive treatment construction method and aggressive treatment construction method was carried out. This paper also makes suggestions for further research directions and subjects, which will be useful in improving the theories in relevant research fields.

Optimization of series-parallel multi-state systems under maintenance policies

International Nuclear Information System (INIS)

Nourelfath, Mustapha; Ait-Kadi, Daoud

2007-01-01

In the redundancy optimization problem, the design goal is achieved by discrete choices made from components available in the market. In this paper, the problem is to find, under reliability constraints, the minimal cost configuration of a multi-state series-parallel system, which is subject to a specified maintenance policy. The number of maintenance teams is less than the number of repairable components, and a maintenance policy specifies the priorities between the system components. To take into account the dependencies resulting from the sharing of maintenance teams, the universal generating function approach is coupled with a Markov model. The resulting optimization approach has the advantage of being mainly analytical

Dynamic modeling and optimal joint torque coordination of advanced robotic systems

Science.gov (United States)

Kang, Hee-Jun

The development is documented of an efficient dynamic modeling algorithm and the subsequent optimal joint input load coordination of advanced robotic systems for industrial application. A closed-form dynamic modeling algorithm for the general closed-chain robotic linkage systems is presented. The algorithm is based on the transfer of system dependence from a set of open chain Lagrangian coordinates to any desired system generalized coordinate set of the closed-chain. Three different techniques for evaluation of the kinematic closed chain constraints allow the representation of the dynamic modeling parameters in terms of system generalized coordinates and have no restriction with regard to kinematic redundancy. The total computational requirement of the closed-chain system model is largely dependent on the computation required for the dynamic model of an open kinematic chain. In order to improve computational efficiency, modification of an existing open-chain KIC based dynamic formulation is made by the introduction of the generalized augmented body concept. This algorithm allows a 44 pct. computational saving over the current optimized one (O(N4), 5995 when N = 6). As means of resolving redundancies in advanced robotic systems, local joint torque optimization is applied for effectively using actuator power while avoiding joint torque limits. The stability problem in local joint torque optimization schemes is eliminated by using fictitious dissipating forces which act in the necessary null space. The performance index representing the global torque norm is shown to be satisfactory. In addition, the resulting joint motion trajectory becomes conservative, after a transient stage, for repetitive cyclic end-effector trajectories. The effectiveness of the null space damping method is shown. The modular robot, which is built of well defined structural modules from a finite-size inventory and is controlled by one general computer system, is another class of evolving

Multi-optimization Criteria-based Robot Behavioral Adaptability and Motion Planning

International Nuclear Information System (INIS)

Pin, Francois G.

2002-01-01

Robotic tasks are typically defined in Task Space (e.g., the 3-D World), whereas robots are controlled in Joint Space (motors). The transformation from Task Space to Joint Space must consider the task objectives (e.g., high precision, strength optimization, torque optimization), the task constraints (e.g., obstacles, joint limits, non-holonomic constraints, contact or tool task constraints), and the robot kinematics configuration (e.g., tools, type of joints, mobile platform, manipulator, modular additions, locked joints). Commercially available robots are optimized for a specific set of tasks, objectives and constraints and, therefore, their control codes are extremely specific to a particular set of conditions. Thus, there exist a multiplicity of codes, each handling a particular set of conditions, but none suitable for use on robots with widely varying tasks, objectives, constraints, or environments. On the other hand, most DOE missions and tasks are typically ''batches of one''. Attempting to use commercial codes for such work requires significant personnel and schedule costs for re-programming or adding code to the robots whenever a change in task objective, robot configuration, number and type of constraint, etc. occurs. The objective of our project is to develop a ''generic code'' to implement this Task-space to Joint-Space transformation that would allow robot behavior adaptation, in real time (at loop rate), to changes in task objectives, number and type of constraints, modes of controls, kinematics configuration (e.g., new tools, added module). Our specific goal is to develop a single code for the general solution of under-specified systems of algebraic equations that is suitable for solving the inverse kinematics of robots, is useable for all types of robots (mobile robots, manipulators, mobile manipulators, etc.) with no limitation on the number of joints and the number of controlled Task-Space variables, can adapt to real time changes in number and

Multiprocessor development for robot control

International Nuclear Information System (INIS)

Lee, Jong Min; Kim, Seung Ho; Hwang, Suk Yeoung; Sohn, Surg Won; Kim, Byung Soo; Kim, Chang Hoi; Lee, Yong Bum; Kim, Woong Ki

1988-12-01

The object of this project is to develop a multiprocessor system which is essential to robot technology. A multiprocessor system interconnecting many single board computer is much faster and flexible than a single processor. The developed multiprocessor will be used to control nuclear mobile robot, so a loosely coupled system is adopted as a robot controller. A total configuration of controller is divided into three main parts in related with its function. It is consisted of supervisory control part, functional control part, remote control part. The designed control system is to be expanded easily for further use with a modular architecture, so the functional independency within sub-systems can be obtained throughout the system structure. Electromagnetic interference affecting to the control system is minimized by using optical fiber as communication media between robot and control system. System performances is enhanced not only by using distributed architecture in hardware, but by adopting real-time, multi-tasking operating system in software. The iRMX86 OS is used and reconfigured for real-time, multi-tasking operation. RS-485 serial communication protocol is used between functional control part and remote control part. Since the developed multiprocessor control system is an essential and fundamental technology for artificial intelligent robot, the result of this project can be applied directly to nuclear mobile robot. (Author)

Implementations of a four-level mechanical architecture for fault-tolerant robots

International Nuclear Information System (INIS)

Hooper, Richard; Sreevijayan, Dev; Tesar, Delbert; Geisinger, Joseph; Kapoor, Chelan

1996-01-01

This paper describes a fault tolerant mechanical architecture with four levels devised and implemented in concert with NASA (Tesar, D. and Sreevijayan, D., Four-level fault tolerance in manipulator design for space operations. In First Int. Symp. Measurement and Control in Robotics (ISMCR '90), Houston, Texas, 20-22 June 1990.) Subsequent work has clarified and revised the architecture. The four levels proceed from fault tolerance at the actuator level, to fault tolerance via in-parallel chains, to fault tolerance using serial kinematic redundancy, and finally to the fault tolerance multiple arm systems provide. This is a subsumptive architecture because each successive layer can incorporate the fault tolerance provided by all layers beneath. For instance a serially-redundant robot can incorporate dual fault-tolerant actuators. Redundant systems provide the fault tolerance, but the guiding principle of this architecture is that functional redundancies actively increase the performance of the system. Redundancies do not simply remain dormant until needed. This paper includes specific examples of hardware and/or software implementation at all four levels

Tuning Bacterial Hydrodynamics with Magnetic Fields: A Path to Bacterial Robotics

Science.gov (United States)

Pierce, Christopher; Mumper, Eric; Brangham, Jack; Wijesinghe, Hiran; Lower, Stephen; Lower, Brian; Yang, Fengyuan; Sooryakumar, Ratnasingham

Magnetotactic Bacteria (MTB) are a group of motile prokaryotes that synthesize chains of lipid-bound, magnetic nano-particles. In this study, the innate magnetism of these flagellated swimmers is exploited to explore their hydrodynamics near confining surfaces, using the magnetic field as a tuning parameter. With weak (Gauss), uniform, external, magnetic ?elds and the field gradients arising from micro-magnetic surface patterns, the relative strength of hydrodynamic, magnetic and ?agellar force components is tuned through magnetic control of the bacteria's orientation and position. In addition to direct measurement of several hydrodynamic quantities related to the motility of individual cells, their tunable dynamics reveal a number of novel, highly controllable swimming behaviors with potential value in micro-robotics applications. Specifically, the experiments permit the MTB cells to be directed along parallel or divergent trajectories, suppress their flagellar forces through magnetic means, and induce transitions between planar, circulating trajectories and drifting, vertically oriented ``top-like'' motion. The implications of the work for fundamental hydrodynamics research as well as bacterially driven robotics applications will be discussed.

Electric field and dielectrophoretic force on a dielectric particle chain in a parallel-plate electrode system

International Nuclear Information System (INIS)

Techaumnat, B; Eua-arporn, B; Takuma, T

2004-01-01

This paper presents results of calculations of the electric field and dielectrophoretic force on a dielectric particle chain suspended in a host liquid lying between parallel-plate electrodes. The method of calculation is based on the method of multipole images using the multipole re-expansion technique. We have investigated the effect of the particle permittivity, the tilt angle (between the chain and the applied field) and the chain arrangement on the electric field and force. The results show that the electric field intensification rises in accordance with the increase in the ratio of the particle-to-liquid permittivity, Γ ε . The electric field at the contact point between the particles decreases with increasing tilt angle, while the maximal field at the contact point between the particles and the plate electrodes is almost unchanged. The maximal field can be approximated by a simple formula, which is a quadratic function of Γ ε . The dielectrophoretic force depends significantly on the distance from other particles or an electrode. However, for the tilt angles in this paper, the horizontal force on the upper particle of the chain always has the direction opposite to the shear direction. The maximal horizontal force of a chain varies proportional to (Γ ε - 1) 1.7 if the particles in the chain are still in contact with each other. The approximated force, based on the force on an isolated chain, has been compared with our calculation results. The comparison shows that no approximation model agrees well with our results throughout the range of permittivity ratios

Design of an Embedded Multi-Camera Vision System—A Case Study in Mobile Robotics

Directory of Open Access Journals (Sweden)

Valter Costa

2018-02-01

Full Text Available The purpose of this work is to explore the design principles for a Real-Time Robotic Multi Camera Vision System, in a case study involving a real world competition of autonomous driving. Design practices from vision and real-time research areas are applied into a Real-Time Robotic Vision application, thus exemplifying good algorithm design practices, the advantages of employing the “zero copy one pass” methodology and associated trade-offs leading to the selection of a controller platform. The vision tasks under study are: (i recognition of a “flat” signal; and (ii track following, requiring 3D reconstruction. This research firstly improves the used algorithms for the mentioned tasks and finally selects the controller hardware. Optimization for the shown algorithms yielded from 1.5 times to 190 times improvements, always with acceptable quality for the target application, with algorithm optimization being more important on lower computing power platforms. Results also include a 3-cm and five-degree accuracy for lane tracking and 100% accuracy for signalling panel recognition, which are better than most results found in the literature for this application. Clear results comparing different PC platforms for the mentioned Robotic Vision tasks are also shown, demonstrating trade-offs between accuracy and computing power, leading to the proper choice of control platform. The presented design principles are portable to other applications, where Real-Time constraints exist.

Discrete Cosserat Approach for Multi-Section Soft Robots Dynamics

OpenAIRE

Renda, Federico; Boyer, Frederic; Dias, Jorge; Seneviratne, Lakmal

2017-01-01

In spite of recent progress, soft robotics still suffers from a lack of unified modeling framework. Nowadays, the most adopted model for the design and control of soft robots is the piece-wise constant curvature model, with its consolidated benefits and drawbacks. In this work, an alternative model for multisection soft robots dynamics is presented based on a discrete Cosserat approach, which, not only takes into account shear and torsional deformations, essentials to cope with out-of-plane e...

Selection of rendezvous points for multi-robot exploration in dynamic environments

NARCIS (Netherlands)

de Hoog, J.; Cameron, S.; Visser, A.; Visser, U.; Asadi, S.; Laue, T.; Mayer, N.M.

2010-01-01

For many robotics applications (such as robotic search and rescue), information about the environment must be gathered by a team of robots and returned to a single, specific location. Coordination of robots and sharing of information is vital, and when environments have severe communication

Localization of Wheeled Mobile Robot Based on Extended Kalman Filtering

Directory of Open Access Journals (Sweden)

Li Guangxu

2015-01-01

Full Text Available A mobile robot localization method which combines relative positioning with absolute orientation is presented. The code salver and gyroscope are used for relative positioning, and the laser radar is used to detect absolute orientation. In this paper, we established environmental map, multi-sensor information fusion model, sensors and robot motion model. The Extended Kalman Filtering (EKF is adopted as multi-sensor data fusion technology to realize the precise localization of wheeled mobile robot.

3rd IFToMM Symposium on Mechanism Design for Robotics

CERN Document Server

Ceccarelli, Marco

2015-01-01

This volume contains the Proceedings of the 3rd IFToMM Symposium on Mechanism Design for Robotics, held in Aalborg, Denmark, 2-4 June, 2015. The book contains papers on recent advances in the design of mechanisms and their robotic applications. It treats the following topics: mechanism design, mechanics of robots, parallel manipulators, actuators and their control, linkage and industrial manipulators, innovative mechanisms/robots and their applications, among others. The book can be used by researchers and engineers in the relevant areas of mechanisms, machines and robotics.

Service orientation in holonic and multi agent manufacturing and robotics

CERN Document Server

Thomas, Andre; Trentesaux, Damien

2013-01-01

The book covers four research domains representing a trend for modern manufacturing control: Holonic and Multi-agent technologies for industrial systems; Intelligent Product and Product-driven Automation; Service Orientation of Enterprise’s strategic and technical processes; and Distributed Intelligent Automation Systems. These evolution lines have in common concepts related to service orientation derived from the Service Oriented Architecture (SOA) paradigm.     The service-oriented multi-agent systems approach discussed in the book is characterized by the use of a set of distributed autonomous and cooperative agents, embedded in smart components that use the SOA principles, being oriented by offer and request of services, in order to fulfil production systems and value chain goals.   A new integrated vision combining emergent technologies is offered, to create control structures with distributed intelligence supporting the vertical and horizontal enterprise integration and running in truly distributed ...

Kullback-Leibler Divergence-Based Differential Evolution Markov Chain Filter for Global Localization of Mobile Robots.

Science.gov (United States)

Martín, Fernando; Moreno, Luis; Garrido, Santiago; Blanco, Dolores

2015-09-16

One of the most important skills desired for a mobile robot is the ability to obtain its own location even in challenging environments. The information provided by the sensing system is used here to solve the global localization problem. In our previous work, we designed different algorithms founded on evolutionary strategies in order to solve the aforementioned task. The latest developments are presented in this paper. The engine of the localization module is a combination of the Markov chain Monte Carlo sampling technique and the Differential Evolution method, which results in a particle filter based on the minimization of a fitness function. The robot's pose is estimated from a set of possible locations weighted by a cost value. The measurements of the perceptive sensors are used together with the predicted ones in a known map to define a cost function to optimize. Although most localization methods rely on quadratic fitness functions, the sensed information is processed asymmetrically in this filter. The Kullback-Leibler divergence is the basis of a cost function that makes it possible to deal with different types of occlusions. The algorithm performance has been checked in a real map. The results are excellent in environments with dynamic and unmodeled obstacles, a fact that causes occlusions in the sensing area.

Robot-assisted 3D-TRUS guided prostate brachytherapy: System integration and validation

International Nuclear Information System (INIS)

Wei Zhouping; Wan Gang; Gardi, Lori; Mills, Gregory; Downey, Donal; Fenster, Aaron

2004-01-01

Current transperineal prostate brachytherapy uses transrectal ultrasound (TRUS) guidance and a template at a fixed position to guide needles along parallel trajectories. However, pubic arch interference (PAI) with the implant path obstructs part of the prostate from being targeted by the brachytherapy needles along parallel trajectories. To solve the PAI problem, some investigators have explored other insertion trajectories than parallel, i.e., oblique. However, parallel trajectory constraints in current brachytherapy procedure do not allow oblique insertion. In this paper, we describe a robot-assisted, three-dimensional (3D) TRUS guided approach to solve this problem. Our prototype consists of a commercial robot, and a 3D TRUS imaging system including an ultrasound machine, image acquisition apparatus and 3D TRUS image reconstruction, and display software. In our approach, we use the robot as a movable needle guide, i.e., the robot positions the needle before insertion, but the physician inserts the needle into the patient's prostate. In a later phase of our work, we will include robot insertion. By unifying the robot, ultrasound transducer, and the 3D TRUS image coordinate systems, the position of the template hole can be accurately related to 3D TRUS image coordinate system, allowing accurate and consistent insertion of the needle via the template hole into the targeted position in the prostate. The unification of the various coordinate systems includes two steps, i.e., 3D image calibration and robot calibration. Our testing of the system showed that the needle placement accuracy of the robot system at the 'patient's' skin position was 0.15 mm±0.06 mm, and the mean needle angulation error was 0.07 deg. . The fiducial localization error (FLE) in localizing the intersections of the nylon strings for image calibration was 0.13 mm, and the FLE in localizing the divots for robot calibration was 0.37 mm. The fiducial registration error for image calibration was 0

Parallel Work of CO2 Ejectors Installed in a Multi-Ejector Module of Refrigeration System

Science.gov (United States)

Bodys, Jakub; Palacz, Michal; Haida, Michal; Smolka, Jacek; Nowak, Andrzej J.; Banasiak, Krzysztof; Hafner, Armin

2016-09-01

A performance analysis on of fixed ejectors installed in a multi-ejector module in a CO2 refrigeration system is presented in this study. The serial and the parallel work of four fixed-geometry units that compose the multi-ejector pack was carried out. The executed numerical simulations were performed with the use of validated Homogeneous Equilibrium Model (HEM). The computational tool ejectorPL for typical transcritical parameters at the motive nozzle were used in all the tests. A wide range of the operating conditions for supermarket applications in three different European climate zones were taken into consideration. The obtained results present the high and stable performance of all the ejectors in the multi-ejector pack.

Hybrid System Design for the Coordination of Multi-Modal Aerial Robots

DEFF Research Database (Denmark)

Koo, T. John; Quottrup, Michael Melholt; Clifton, C. A.

2006-01-01

In this paper we provide a framework for the coordination of a network of heterogeneous aerial robots by using temporal logic to formulate mission speci¯cations for the network of robots. The full dynamics of the aerial robots are considered, and multiple controllers that can cope with various......¯ed. These robots are coordinated by communicating through a single occupancy table. By using the model checker Uppaal, a discrete plan that satis¯es a given temporal logic formula, speci¯ed in CTL, is generated for the robot to execute. Finally, the discrete plan for each robot is re¯ned into a discrete control...... constraints are designed to ensure that desired reachability properties can be preserved by properly switching among the controllers. A timed automaton is then constructed for preserving the temporal properties of a given robot. For di®erent types of robots, unique temporal properties can be speci...

A Lie-Theoretic Perspective on O(n) Mass Matrix Inversion for Serial Manipulators and Polypeptide Chains.

Science.gov (United States)

Lee, Kiju; Wang, Yunfeng; Chirikjian, Gregory S

2007-11-01

Over the past several decades a number of O(n) methods for forward and inverse dynamics computations have been developed in the multi-body dynamics and robotics literature. A method was developed in 1974 by Fixman for O(n) computation of the mass-matrix determinant for a serial polymer chain consisting of point masses. In other recent papers, we extended this method in order to compute the inverse of the mass matrix for serial chains consisting of point masses. In the present paper, we extend these ideas further and address the case of serial chains composed of rigid-bodies. This requires the use of relatively deep mathematics associated with the rotation group, SO(3), and the special Euclidean group, SE(3), and specifically, it requires that one differentiates functions of Lie-group-valued argument.

Motion Planning in Multi-robot Systems using Timed Automata

DEFF Research Database (Denmark)

Andersen, Michael. S.; Jensen, Rune S.; Bak, Thomas

This paper dscribes how interacting timed automata can be used to model, analyze, and verify motion planning problems for systems with multiple mobile robots. The method assumes an infra-structure of simple unicycle type robots, moving om a planar grid. The motion of the robots, including simple...... kinematics, is captured in an automata formalism that allows formal composition and symbolic reasoning. The verification software UppAal is used to verify specification requirements formulated in computational tree logic (CTL), generating all feasible trajectories that satisfy specifications. The results...... of the planning are demonstrateted in a testbed that allows execution of the planned paths and motion primitives by synchronizing the planning results from UppAal with actual robotic vehicles. The planning problem may be modified online by moving obstacles in the physical environment, which causes a re...

Biological Immune System Applications on Mobile Robot for Disabled People

Directory of Open Access Journals (Sweden)

Songmin Jia

2014-01-01

Full Text Available To improve the service quality of service robots for the disabled, immune system is applied on robot for its advantages such as diversity, dynamic, parallel management, self-organization, and self-adaptation. According to the immune system theory, local environment condition sensed by robot is considered an antigen while robot is regarded as B-cell and possible node as antibody, respectively. Antibody-antigen affinity is employed to choose the optimal possible node to ensure the service robot can pass through the optimal path. The paper details the immune system applications on service robot and gives experimental results.

Soft Robotic Manipulation of Onions and Artichokes in the Food Industry

Directory of Open Access Journals (Sweden)

R. Morales

2014-04-01

Full Text Available This paper presents the development of a robotic solution for a problem of fast manipulation and handling of onions or artichokes in the food industry. The complete solution consists of a parallel robotic manipulatior, a specially designed end-effector based on a customized vacuum suction cup, and a computer vision software developed for pick and place operations. First, the selection and design process of the proposed robotic solution to fit with the initial requeriments is presented, including the customized vacuum suction cup. Then, the kinematic analysis of the parallel manipulator needed to develop the robot control system is reviewed. Moreover, computer vision application is presented inthe paper. Hardware details of the implementation of the building prototype are also shown. Finally, conclusions and future work show the current status of the project.

Generic Automated Multi-function Finger Design

Science.gov (United States)

Honarpardaz, M.; Tarkian, M.; Sirkett, D.; Ölvander, J.; Feng, X.; Elf, J.; Sjögren, R.

2016-11-01

Multi-function fingers that are able to handle multiple workpieces are crucial in improvement of a robot workcell. Design automation of multi-function fingers is highly demanded by robot industries to overcome the current iterative, time consuming and complex manual design process. However, the existing approaches for the multi-function finger design automation are unable to entirely meet the robot industries’ need. This paper proposes a generic approach for design automation of multi-function fingers. The proposed approach completely automates the design process and requires no expert skill. In addition, this approach executes the design process much faster than the current manual process. To validate the approach, multi-function fingers are successfully designed for two case studies. Further, the results are discussed and benchmarked with existing approaches.

Cooperative robots and sensor networks 2015

CERN Document Server

Dios, JRamiro

2015-01-01

This book compiles some of the latest research in cooperation between robots and sensor networks. Structured in twelve chapters, this book addresses fundamental, theoretical, implementation and experimentation issues. The chapters are organized into four parts namely multi-robots systems, data fusion and localization, security and dependability, and mobility.

Mechanical design for a hydraulically actuated quadruped robot

OpenAIRE

Erkekli, Koray

2017-01-01

Considerable amount of research efforts are spent on the field of legged robotics in the past 60 years. Studies in this area extend from running on one leg to humanoid robots, from four legged robots (quadruped) to multi-legged bug-inspired robots. The advantage of four legged structure is that it is more balanced compared structures with less legs. This feature makes four legged robots candidates rough terrain conditions and for dangerous tasks. Because of the high power-to-weight ratio and ...

A hardware investigation of robotic SPECT for functional and molecular imaging onboard radiation therapy systems

International Nuclear Information System (INIS)

Yan, Susu; Tough, MengHeng; Bowsher, James; Yin, Fang-Fang; Cheng, Lin

2014-01-01

Purpose: To construct a robotic SPECT system and to demonstrate its capability to image a thorax phantom on a radiation therapy flat-top couch, as a step toward onboard functional and molecular imaging in radiation therapy. Methods: A robotic SPECT imaging system was constructed utilizing a gamma camera detector (Digirad 2020tc) and a robot (KUKA KR150 L110 robot). An imaging study was performed with a phantom (PET CT Phantom TM ), which includes five spheres of 10, 13, 17, 22, and 28 mm diameters. The phantom was placed on a flat-top couch. SPECT projections were acquired either with a parallel-hole collimator or a single-pinhole collimator, both without background in the phantom and with background at 1/10th the sphere activity concentration. The imaging trajectories of parallel-hole and pinhole collimated detectors spanned 180° and 228°, respectively. The pinhole detector viewed an off-centered spherical common volume which encompassed the 28 and 22 mm spheres. The common volume for parallel-hole system was centered at the phantom which encompassed all five spheres in the phantom. The maneuverability of the robotic system was tested by navigating the detector to trace the phantom and flat-top table while avoiding collision and maintaining the closest possible proximity to the common volume. The robot base and tool coordinates were used for image reconstruction. Results: The robotic SPECT system was able to maneuver parallel-hole and pinhole collimated SPECT detectors in close proximity to the phantom, minimizing impact of the flat-top couch on detector radius of rotation. Without background, all five spheres were visible in the reconstructed parallel-hole image, while four spheres, all except the smallest one, were visible in the reconstructed pinhole image. With background, three spheres of 17, 22, and 28 mm diameters were readily observed with the parallel-hole imaging, and the targeted spheres (22 and 28 mm diameters) were readily observed in the pinhole

Iconic Gestures for Robot Avatars, Recognition and Integration with Speech

Science.gov (United States)

Bremner, Paul; Leonards, Ute

2016-01-01

Co-verbal gestures are an important part of human communication, improving its efficiency and efficacy for information conveyance. One possible means by which such multi-modal communication might be realized remotely is through the use of a tele-operated humanoid robot avatar. Such avatars have been previously shown to enhance social presence and operator salience. We present a motion tracking based tele-operation system for the NAO robot platform that allows direct transmission of speech and gestures produced by the operator. To assess the capabilities of this system for transmitting multi-modal communication, we have conducted a user study that investigated if robot-produced iconic gestures are comprehensible, and are integrated with speech. Robot performed gesture outcomes were compared directly to those for gestures produced by a human actor, using a within participant experimental design. We show that iconic gestures produced by a tele-operated robot are understood by participants when presented alone, almost as well as when produced by a human. More importantly, we show that gestures are integrated with speech when presented as part of a multi-modal communication equally well for human and robot performances. PMID:26925010

Iconic Gestures for Robot Avatars, Recognition and Integration with Speech

Directory of Open Access Journals (Sweden)

Paul Adam Bremner

2016-02-01

Full Text Available Co-verbal gestures are an important part of human communication, improving its efficiency and efficacy for information conveyance. One possible means by which such multi-modal communication might be realised remotely is through the use of a tele-operated humanoid robot avatar. Such avatars have been previously shown to enhance social presence and operator salience. We present a motion tracking based tele-operation system for the NAO robot platform that allows direct transmission of speech and gestures produced by the operator. To assess the capabilities of this system for transmitting multi-modal communication, we have conducted a user study that investigated if robot-produced iconic gestures are comprehensible, and are integrated with speech. Robot performed gesture outcomes were compared directly to those for gestures produced by a human actor, using a within participant experimental design. We show that iconic gestures produced by a tele-operated robot are understood by participants when presented alone, almost as well as when produced by a human. More importantly, we show that gestures are integrated with speech when presented as part of a multi-modal communication equally well for human and robot performances.

Integrating Multi-Purpose Natural Language Understanding, Robot's Memory, and Symbolic Planning for Task Execution in Humanoid Robots

DEFF Research Database (Denmark)

Wächter, Mirko; Ovchinnikova, Ekaterina; Wittenbeck, Valerij

2017-01-01

We propose an approach for instructing a robot using natural language to solve complex tasks in a dynamic environment. In this study, we elaborate on a framework that allows a humanoid robot to understand natural language, derive symbolic representations of its sensorimotor experience, generate....... The framework is implemented within the robot development environment ArmarX. We evaluate the framework on the humanoid robot ARMAR-III in the context of two experiments: a demonstration of the real execution of a complex task in the kitchen environment on ARMAR-III and an experiment with untrained users...

Multi-focal Vision and Gaze Control Improve Navigation Performance

Directory of Open Access Journals (Sweden)

Kolja Kuehnlenz

2008-11-01

Full Text Available Multi-focal vision systems comprise cameras with various fields of view and measurement accuracies. This article presents a multi-focal approach to localization and mapping of mobile robots with active vision. An implementation of the novel concept is done considering a humanoid robot navigation scenario where the robot is visually guided through a structured environment with several landmarks. Various embodiments of multi-focal vision systems are investigated and the impact on navigation performance is evaluated in comparison to a conventional mono-focal stereo set-up. The comparative studies clearly show the benefits of multi-focal vision for mobile robot navigation: flexibility to assign the different available sensors optimally in each situation, enhancement of the visible field, higher localization accuracy, and, thus, better task performance, i.e. path following behavior of the mobile robot. It is shown that multi-focal vision may strongly improve navigation performance.

Experiments on co-operating robot arms

International Nuclear Information System (INIS)

Arthaya, B.; De Schutter, J.

1994-01-01

When two robots manipulate a common object or perform a single task together, a closed-kinematic chain is formed. If both robots are controlled under position control only, at a certain phase during the manipulation, the interaction forces may become unacceptably high. The interaction forces are caused by the kinematic as well as the dynamic errors in the robot position controller. In order to avoid this problem, a synchronized motion between both robots has to be generated, not only by controlling the position (velocity) of the two end-effectors, but also by controlling the interaction forces between them. In order to generate a synchronized motion, the first robot controller continuously modifies the task frame velocity corresponding to the velocity of the other robot. This implies that the velocity of the other robot is used as feed-forward information in order to anticipate its motion. This approach results in a better tracking behaviour

Sustainable and Resilient Garment Supply Chain Network Design with Fuzzy Multi-Objectives under Uncertainty

Directory of Open Access Journals (Sweden)

Sonia Irshad Mari

2016-10-01

Full Text Available Researchers and practitioners are taking more interest in developing sustainable garment supply chains in recent times. On the other hand, the supply chain manager drops sustainability objectives while coping with unexpected natural and man-made disruption risks. Hence, supply chain managers are now trying to develop sustainable supply chains that are simultaneously resilient enough to cope with disruption risks. Owing to the importance of the considered issue, this study proposed a network optimization model for a sustainable and resilient supply chain network by considering sustainability via embodied carbon footprints and carbon emissions and resilience by considering resilience index. In this paper, initially, a possibilistic fuzzy multi-objective sustainable and resilient supply chain network model is developed for the garment industry considering economic, sustainable, and resilience objectives. Secondly, a possibilistic fuzzy linguistic weight-based interactive solution method is proposed. Finally, a numerical case example is presented to show the applicability of the proposed model and solution methodology.

Grasp Algorithms For Optotactile Robotic Sample Acquisition, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Robotic sample acquisition is basically grasping. Multi-finger robot sample grasping devices are controlled to securely pick up samples. While optimal grasps for...

Characteristics of manipulator for industrial robot with three rotational pairs having parallel axes

Science.gov (United States)

Poteyev, M. I.

1986-01-01

The dynamics of a manipulator with three rotatinal kinematic pairs having parallel axes are analyzed, for application in an industrial robot. The system of Lagrange equations of the second kind, describing the motion of such a mechanism in terms of kinetic energy in generalized coordinates, is reduced to equations of motion in terms of Newton's laws. These are useful not only for either determining the moments of force couples which will produce a prescribed motion or, conversely determining the motion which given force couples will produce but also for solving optimization problems under constraints in both cases and for estimating dynamic errors. As a specific example, a manipulator with all three axes of vertical rotation is considered. The performance of this manipulator, namely the parameters of its motion as functions of time, is compared with that of a manipulator having one rotational and two translational kinematic pairs. Computer aided simulation of their motion on the basis of ideal models, with all three links represented by identical homogeneous bars, has yielded velocity time diagrams which indicate that the manipulator with three rotational pairs is 4.5 times faster.

Availability modeling and optimization of dynamic multi-state series–parallel systems with random reconfiguration