A 3D motion planning framework for snake robots

OpenAIRE

Liljebäck, Pål; Pettersen, Kristin Ytterstad; Stavdahl, Øyvind; Gravdahl, Jan Tommy

2014-01-01

- Author's postprint This paper presents a motion planning framework for three-dimensional body shape control of snake robots. Whereas conventional motion planning approaches define the body shape of snake robots in terms of their individual joint angles, the proposed framework allows the body shape to be specified in terms of Cartesian coordinates in the environment of the robot. This approach simplifies motion planning since Cartesian coordinates are more intuitively mapped to the overal...

An Exoskeleton Robot for Human Forearm and Wrist Motion Assist

Science.gov (United States)

Ranathunga Arachchilage Ruwan Chandra Gopura; Kiguchi, Kazuo

The exoskeleton robot is worn by the human operator as an orthotic device. Its joints and links correspond to those of the human body. The same system operated in different modes can be used for different fundamental applications; a human-amplifier, haptic interface, rehabilitation device and assistive device sharing a portion of the external load with the operator. We have been developing exoskeleton robots for assisting the motion of physically weak individuals such as elderly or slightly disabled in daily life. In this paper, we propose a three degree of freedom (3DOF) exoskeleton robot (W-EXOS) for the forearm pronation/ supination motion, wrist flexion/extension motion and ulnar/radial deviation. The paper describes the wrist anatomy toward the development of the exoskeleton robot, the hardware design of the exoskeleton robot and EMG-based control method. The skin surface electromyographic (EMG) signals of muscles in forearm of the exoskeletons' user and the hand force/forearm torque are used as input information for the controller. By applying the skin surface EMG signals as main input signals to the controller, automatic control of the robot can be realized without manipulating any other equipment. Fuzzy control method has been applied to realize the natural and flexible motion assist. Experiments have been performed to evaluate the proposed exoskeleton robot and its control method.

Magnetic fish-robot based on multi-motion control of a flexible magnetic actuator.

Science.gov (United States)

Kim, Sung Hoon; Shin, Kyoosik; Hashi, Shuichiro; Ishiyama, Kazushi

2012-09-01

This paper presents a biologically inspired fish-robot driven by a single flexible magnetic actuator with a rotating magnetic field in a three-axis Helmholtz coil. Generally, magnetic fish-robots are powered by alternating and gradient magnetic fields, which provide a single motion such as bending the fish-robot's fins. On the other hand, a flexible magnetic actuator driven by an external rotating magnetic field can create several gaits such as the bending vibration, the twisting vibration, and their combination. Most magnetic fish-like micro-robots do not have pectoral fins on the side and are simply propelled by the tail fin. The proposed robot can swim and perform a variety of maneuvers with the addition of pectoral fins and control of the magnetic torque direction. In this paper, we find that the robot's dynamic actuation correlates with the magnetic actuator and the rotating magnetic field. The proposed robot is also equipped with new features, such as a total of six degrees of freedom, a new control method that stabilizes posture, three-dimensional swimming, a new velocity control, and new turning abilities.

Magnetic fish-robot based on multi-motion control of a flexible magnetic actuator

International Nuclear Information System (INIS)

Kim, Sung Hoon; Hashi, Shuichiro; Ishiyama, Kazushi; Shin, Kyoosik

2012-01-01

This paper presents a biologically inspired fish-robot driven by a single flexible magnetic actuator with a rotating magnetic field in a three-axis Helmholtz coil. Generally, magnetic fish-robots are powered by alternating and gradient magnetic fields, which provide a single motion such as bending the fish-robot's fins. On the other hand, a flexible magnetic actuator driven by an external rotating magnetic field can create several gaits such as the bending vibration, the twisting vibration, and their combination. Most magnetic fish-like micro-robots do not have pectoral fins on the side and are simply propelled by the tail fin. The proposed robot can swim and perform a variety of maneuvers with the addition of pectoral fins and control of the magnetic torque direction. In this paper, we find that the robot's dynamic actuation correlates with the magnetic actuator and the rotating magnetic field. The proposed robot is also equipped with new features, such as a total of six degrees of freedom, a new control method that stabilizes posture, three-dimensional swimming, a new velocity control, and new turning abilities. (paper)

Neural Network Control for the Linear Motion of a Spherical Mobile Robot

Directory of Open Access Journals (Sweden)

Yao Cai

2011-09-01

Full Text Available This paper discussed the stabilization and position tracking control of the linear motion of an underactuated spherical robot. By considering the actuator dynamics, a complete dynamic model of the robot is deduced, which is a complex third order, two variables nonlinear differential system and those two variables have strong coupling due to the mechanical structure of the robot. Different from traditional treatments, no linearization is applied to this system but a single‐input multiple‐output PID (SIMO_PID controller is designed by adopting a six‐input single‐ output CMAC_GBF (Cerebellar Model Articulation Controller with General Basis Function neural network to compensate the actuator nonlinearity and the credit assignment (CA learning method to obtain faster convergence of CMAC_GBF. The proposed controller is generalizable to other single‐input multiple‐output system with good real‐time capability. Simulations in Matlab are used to validate the control effects.

Hybrid task priority-based motion control of a redundant free-floating space robot

Directory of Open Access Journals (Sweden)

Cheng ZHOU

2017-12-01

Full Text Available This paper presents a novel hybrid task priority-based motion planning algorithm of a space robot. The satellite attitude control task is defined as the primary task, while the least-squares-based non-strict task priority solution of the end-effector plus the multi-constraint task is viewed as the secondary task. Furthermore, a null-space task compensation strategy in the joint space is proposed to derive the combination of non-strict and strict task-priority motion planning, and this novel combination is termed hybrid task priority control. Thus, the secondary task is implemented in the primary task’s null-space. Besides, the transition of the state of multiple constraints between activeness and inactiveness will only influence the end-effector task without any effect on the primary task. A set of numerical experiments made in a real-time simulation system under Linux/RTAI shows the validity and feasibility of the proposed methodology. Keywords: Base attitude control, Hybrid task-priority, Motion planning, Multiple constraints, Redundant space robot

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....

MOTION PLANNING OF MULTIPLE MOBILE ROBOTS COOPERATIVELY TRANSPORTING A COMMON OBJECT

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

Many applications above the capability of a single robot need the cooperation of multiple mobile robots, but effective cooperation is hard to achieve. In this paper, a master-slave method is proposed to control the motions of multiple mobile robots that cooperatively transport a common object from a start point to a goal point. A noholonomic kinematic model to constrain the motions of multiple mobile robots is built in order to achieve cooperative motions of them, and a "Dynamic Coordinator" strategy is used to deal with the collision-avoidance of the master robot and slave robot individually. Simulation results show the robustness and effectiveness of the method.

Trajectory Planning and Walking Pattern Generation of Humanoid Robot Motion

Directory of Open Access Journals (Sweden)

Saeed Abdolshah

2014-12-01

Full Text Available Walking trajectory generation for a humanoid robot is a challenging control  issue. In this paper, a walking cycle has been recognized considering human motion, and nine simple steps were distinguished in a full step of walking which form motion trajectory, and generates a simplified ZMP motion formulation. This system was used in humanoid robot simulation motion and is achievable easily in walking steps of robot. A minimum DOFs humanoid robot has been considered and geometrical relationships between the robot links were presented by the Denavit-Hartenberg method. The inverse kinematics equations have been solved regarding to extracted ZMP trajectory formula, and constraints in different steps. As a result; angular velocity, acceleration and power of motors were obtained using the relationships and Jacobin. At each step, extracted data were applied on simulated robot in Matlab, and Visual Nastran software. Zero moment point trajectory was evaluated in simulation environment.

Kinematics Control and Analysis of Industrial Robot

Science.gov (United States)

Zhu, Tongbo; Cai, Fan; Li, Yongmei; Liu, Wei

2018-03-01

The robot’s development present situation, basic principle and control system are introduced briefly. Research is mainly focused on the study of the robot’s kinematics and motion control. The structural analysis of a planar articulated robot (SCARA) robot is presented,the coordinate system is established to obtain the position and orientation matrix of the end effector,a method of robot kinematics analysis based on homogeneous transformation method is proposed, and the kinematics solution of the robot is obtained.Establishment of industrial robot’s kinematics equation and formula for positive kinematics by example. Finally,the kinematic analysis of this robot was verified by examples.It provides a basis for structural design and motion control.It has active significance to promote the motion control of industrial robot.

Kinematic control of redundant robots and the motion optimizability measure.

Science.gov (United States)

Li, L; Gruver, W A; Zhang, Q; Yang, Z

2001-01-01

This paper treats the kinematic control of manipulators with redundant degrees of freedom. We derive an analytical solution for the inverse kinematics that provides a means for accommodating joint velocity constraints in real time. We define the motion optimizability measure and use it to develop an efficient method for the optimization of joint trajectories subject to multiple criteria. An implementation of the method for a 7-dof experimental redundant robot is present.

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...

Robotics-based synthesis of human motion

KAUST Repository

Khatib, O.; Demircan, E.; De Sapio, V.; Sentis, L.; Besier, T.; Delp, S.

2009-01-01

The synthesis of human motion is a complex procedure that involves accurate reconstruction of movement sequences, modeling of musculoskeletal kinematics, dynamics and actuation, and characterization of reliable performance criteria. Many of these processes have much in common with the problems found in robotics research. Task-based methods used in robotics may be leveraged to provide novel musculoskeletal modeling methods and physiologically accurate performance predictions. In this paper, we present (i) a new method for the real-time reconstruction of human motion trajectories using direct marker tracking, (ii) a task-driven muscular effort minimization criterion and (iii) new human performance metrics for dynamic characterization of athletic skills. Dynamic motion reconstruction is achieved through the control of a simulated human model to follow the captured marker trajectories in real-time. The operational space control and real-time simulation provide human dynamics at any configuration of the performance. A new criteria of muscular effort minimization has been introduced to analyze human static postures. Extensive motion capture experiments were conducted to validate the new minimization criterion. Finally, new human performance metrics were introduced to study in details an athletic skill. These metrics include the effort expenditure and the feasible set of operational space accelerations during the performance of the skill. The dynamic characterization takes into account skeletal kinematics as well as muscle routing kinematics and force generating capacities. The developments draw upon an advanced musculoskeletal modeling platform and a task-oriented framework for the effective integration of biomechanics and robotics methods.

Robotics-based synthesis of human motion

KAUST Repository

Khatib, O.

2009-05-01

The synthesis of human motion is a complex procedure that involves accurate reconstruction of movement sequences, modeling of musculoskeletal kinematics, dynamics and actuation, and characterization of reliable performance criteria. Many of these processes have much in common with the problems found in robotics research. Task-based methods used in robotics may be leveraged to provide novel musculoskeletal modeling methods and physiologically accurate performance predictions. In this paper, we present (i) a new method for the real-time reconstruction of human motion trajectories using direct marker tracking, (ii) a task-driven muscular effort minimization criterion and (iii) new human performance metrics for dynamic characterization of athletic skills. Dynamic motion reconstruction is achieved through the control of a simulated human model to follow the captured marker trajectories in real-time. The operational space control and real-time simulation provide human dynamics at any configuration of the performance. A new criteria of muscular effort minimization has been introduced to analyze human static postures. Extensive motion capture experiments were conducted to validate the new minimization criterion. Finally, new human performance metrics were introduced to study in details an athletic skill. These metrics include the effort expenditure and the feasible set of operational space accelerations during the performance of the skill. The dynamic characterization takes into account skeletal kinematics as well as muscle routing kinematics and force generating capacities. The developments draw upon an advanced musculoskeletal modeling platform and a task-oriented framework for the effective integration of biomechanics and robotics methods.

Hand/Eye Coordination For Fine Robotic Motion

Science.gov (United States)

Lokshin, Anatole M.

1992-01-01

Fine motions of robotic manipulator controlled with help of visual feedback by new method reducing position errors by order of magnitude. Robotic vision subsystem includes five cameras: three stationary ones providing wide-angle views of workspace and two mounted on wrist of auxiliary robot arm. Stereoscopic cameras on arm give close-up views of object and end effector. Cameras measure errors between commanded and actual positions and/or provide data for mapping between visual and manipulator-joint-angle coordinates.

Distributed formation control for autonomous robots

NARCIS (Netherlands)

Garcia de Marina Peinado, Hector Jesús

2016-01-01

This thesis addresses several theoretical and practical problems related to formation-control of autonomous robots. Formation-control aims to simultaneously accomplish the tasks of forming a desired shape by the robots and controlling their coordinated collective motion. This kind of robot

Neural Networks in Mobile Robot Motion

Directory of Open Access Journals (Sweden)

Danica Janglová

2004-03-01

Full Text Available This paper deals with a path planning and intelligent control of an autonomous robot which should move safely in partially structured environment. This environment may involve any number of obstacles of arbitrary shape and size; some of them are allowed to move. We describe our approach to solving the motion-planning problem in mobile robot control using neural networks-based technique. Our method of the construction of a collision-free path for moving robot among obstacles is based on two neural networks. The first neural network is used to determine the “free” space using ultrasound range finder data. The second neural network “finds” a safe direction for the next robot section of the path in the workspace while avoiding the nearest obstacles. Simulation examples of generated path with proposed techniques will be presented.

Radio Controlled Fish Robot RR-9

OpenAIRE

Cifanskis, S; Vība, J; Jakuševičs, V

2015-01-01

A remote-controlled underwater robot fish is described. For motion control three actuator drives are used: one actuator is for tail frequency exchange, the second actuator is for the left or right turnings and the third actuator provides neutral swimming or up and down diving. From the robot's center of mass motion theorem (according to the given total mass of robot) the proportional distribution of massesof structural elements is found. Experimental indoor and out...

Integration Method of Emphatic Motions and Adverbial Expressions with Scalar Parameters for Robotic Motion Coaching System

Science.gov (United States)

Okuno, Keisuke; Inamura, Tetsunari

A robotic coaching system can improve humans' learning performance of motions by intelligent usage of emphatic motions and adverbial expressions according to user reactions. In robotics, however, method to control both the motions and the expressions and how to bind them had not been adequately discussed from an engineering point of view. In this paper, we propose a method for controlling and binding emphatic motions and adverbial expressions by using two scalar parameters in a phase space. In the phase space, variety of motion patterns and verbal expressions are connected and can be expressed as static points. We show the feasibility of the proposing method through experiments of actual sport coaching tasks for beginners. From the results of participants' improvements in motion learning, we confirmed the feasibility of the methods to control and bind emphatic motions and adverbial expressions, as well as confirmed contribution of the emphatic motions and positive correlation of adverbial expressions for participants' improvements in motion learning. Based on the results, we introduce a hypothesis that individually optimized method for binding adverbial expression is required.

Collision-free motion coordination of heterogeneous robots

Energy Technology Data Exchange (ETDEWEB)

Ko, Nak Yong [Chosun University, Gwangju (Korea, Republic of); Seo, Dong Jin [RedOne Technologies, Gwangju (Korea, Republic of); Simmons, Reid G. [Carnegie Mellon University, Pennsylvania (United States)

2008-11-15

This paper proposes a method to coordinate the motion of multiple heterogeneous robots on a network. The proposed method uses prioritization and avoidance. Priority is assigned to each robot; a robot with lower priority avoids the robots of higher priority. To avoid collision with other robots, elastic force and potential field force are used. Also, the method can be applied separately to the motion planning of a part of a robot from that of the other parts of the robot. This is useful for application to the robots of the type mobile manipulator or highly redundant robots. The method is tested by simulation, and it results in smooth and adaptive coordination in an environment with multiple heterogeneous robots

Collision-free motion coordination of heterogeneous robots

International Nuclear Information System (INIS)

Ko, Nak Yong; Seo, Dong Jin; Simmons, Reid G.

2008-01-01

This paper proposes a method to coordinate the motion of multiple heterogeneous robots on a network. The proposed method uses prioritization and avoidance. Priority is assigned to each robot; a robot with lower priority avoids the robots of higher priority. To avoid collision with other robots, elastic force and potential field force are used. Also, the method can be applied separately to the motion planning of a part of a robot from that of the other parts of the robot. This is useful for application to the robots of the type mobile manipulator or highly redundant robots. The method is tested by simulation, and it results in smooth and adaptive coordination in an environment with multiple heterogeneous robots

The development of advanced robotic technology - A study on the development of Motion capturing system

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong Hyun; Kim, Ki Ho; Lee, Yong Woo; Park, Soo Il; Choi, Jin Sung; Kim, Hae Dong; Park, Chan Yong [System Engineering Research Institute, Taejon= (Korea, Republic of)

1996-07-01

Robots are used to perform jobs where the performer are exposed to the radioactivity. Good human-robot-interface is required to operate the robots easily and smoothly. It is believed that virtual reality and 3D graphics technology will be the beat solution for the good human-robot-interface. Using 3D computer graphics, complex human motions can be captured and displayed on the screen. The captured motion data can be used as the input to= control the remote robots using virtual reality technologies. Thus good human-robot-interface can be constructed. The motion capturing system developed in this study are very convenient and easy to be used to operate the robot. And the required time to operate the robot with the developed system is much shorter than to operate the robots without our motion capturing system. Therefore, efficient usage of the robot and related facilities will prolong the life time of them and reduce the manpower of the operators. The 3D data produced by our system will be used to generate commands to control the robot. 6 refs., 60 figs. (author)

Bio-Inspired Optimal Control Framework to Generate Walking Motions for the Humanoid Robot iCub Using Whole Body Models

Directory of Open Access Journals (Sweden)

Yue Hu

2018-02-01

Full Text Available Bipedal locomotion remains one of the major open challenges of humanoid robotics. The common approaches are based on simple reduced model dynamics to generate walking trajectories, often neglecting the whole-body dynamics of the robots. As motions in nature are often considered as optimal with respect to certain criteria, in this work, we present an optimal control-based approach that allows us to generate optimized walking motions using a precise whole-body dynamic model of the robot, in contrast with the common approaches. The optimal control problem is formulated to minimize a set of desired objective functions with respect to physical constraints of the robot and contact constraints of the walking phases; the problem is then solved with a direct multiple shooting method. We apply the formulation with combinations of different objective criteria to the model of a reduced version of the iCub humanoid robot of 15 internal DOF. The obtained trajectories are executed on the real robot, and we carry out a discussion on the differences between the outcomes of this approach with the classic approaches.

Actuation control of a PiezoMEMS biomimetic robotic jellyfish

Science.gov (United States)

Alejandre, Alvaro; Olszewski, Oskar; Jackson, Nathan

2017-06-01

Biomimetic micro-robots try to mimic the motion of a living system in the form of a synthetically developed microfabricated device. Dynamic motion of living systems have evolved through the years, but trying to mimic these motions is challenging. Micro-robotics are particular challenging as the fabrication of devices and controlling the motion in 3 dimensions is difficult. However, micro-scale robotics have potential to be used in a wide range of applications. MEMS based robots that can move and function in a liquid environment is of particular interest. This paper describes the development of a piezoMEMS based device that mimics the movement of a jellyfish. The paper focuses on the development of a finite element model that investigates a method of controlling the individual piezoelectric beams in order to create a jet propulsion motion, consisting of a quick excitation pulse followed by a slow recovery pulse in order to maximize thrust and velocity. By controlling the individual beams or legs of the jellyfish robot the authors can control the robot to move precisely in 3 dimensions.

An Evolutionary Robotics Approach to the Control of Plant Growth and Motion: Modeling Plants and Crossing the Reality Gap

DEFF Research Database (Denmark)

Wahby, Mostafa; Hofstadler, Daniel Nicolas; Heinrich, Mary Katherine

2016-01-01

The self-organizing bio-hybrid collaboration of robots and natural plants allows for a variety of interesting applications. As an example we investigate how robots can be used to control the growth and motion of a natural plant, using LEDs to provide stimuli. We follow an evolutionary robotics...... approach where task performance is determined by monitoring the plant's reaction. First, we do initial plant experiments with simple, predetermined controllers. Then we use image sampling data as a model of the dynamics of the plant tip xy position. Second, we use this approach to evolve robot controllers...

Virtual Sensors for Advanced Controllers in Rehabilitation Robotics.

Science.gov (United States)

Mancisidor, Aitziber; Zubizarreta, Asier; Cabanes, Itziar; Portillo, Eva; Jung, Je Hyung

2018-03-05

In order to properly control rehabilitation robotic devices, the measurement of interaction force and motion between patient and robot is an essential part. Usually, however, this is a complex task that requires the use of accurate sensors which increase the cost and the complexity of the robotic device. In this work, we address the development of virtual sensors that can be used as an alternative of actual force and motion sensors for the Universal Haptic Pantograph (UHP) rehabilitation robot for upper limbs training. These virtual sensors estimate the force and motion at the contact point where the patient interacts with the robot using the mathematical model of the robotic device and measurement through low cost position sensors. To demonstrate the performance of the proposed virtual sensors, they have been implemented in an advanced position/force controller of the UHP rehabilitation robot and experimentally evaluated. The experimental results reveal that the controller based on the virtual sensors has similar performance to the one using direct measurement (less than 0.005 m and 1.5 N difference in mean error). Hence, the developed virtual sensors to estimate interaction force and motion can be adopted to replace actual precise but normally high-priced sensors which are fundamental components for advanced control of rehabilitation robotic devices.

Virtual Sensors for Advanced Controllers in Rehabilitation Robotics

Directory of Open Access Journals (Sweden)

Aitziber Mancisidor

2018-03-01

Full Text Available In order to properly control rehabilitation robotic devices, the measurement of interaction force and motion between patient and robot is an essential part. Usually, however, this is a complex task that requires the use of accurate sensors which increase the cost and the complexity of the robotic device. In this work, we address the development of virtual sensors that can be used as an alternative of actual force and motion sensors for the Universal Haptic Pantograph (UHP rehabilitation robot for upper limbs training. These virtual sensors estimate the force and motion at the contact point where the patient interacts with the robot using the mathematical model of the robotic device and measurement through low cost position sensors. To demonstrate the performance of the proposed virtual sensors, they have been implemented in an advanced position/force controller of the UHP rehabilitation robot and experimentally evaluated. The experimental results reveal that the controller based on the virtual sensors has similar performance to the one using direct measurement (less than 0.005 m and 1.5 N difference in mean error. Hence, the developed virtual sensors to estimate interaction force and motion can be adopted to replace actual precise but normally high-priced sensors which are fundamental components for advanced control of rehabilitation robotic devices.

Motion planning and synchronized control of the dental arch generator of the tooth-arrangement robot.

Science.gov (United States)

Jiang, Jin-Gang; Zhang, Yong-De

2013-03-01

The traditional, manual method of reproducing the dental arch form is prone to numerous random errors caused by human factors. The purpose of this study was to investigate the automatic acquisition of the dental arch and implement the motion planning and synchronized control of the dental arch generator of the multi-manipulator tooth-arrangement robot for use in full denture manufacture. First, the mathematical model of the dental arch generator was derived. Then the kinematics and control point position of the dental arch generator of the tooth arrangement robot were calculated and motion planning of each control point was analysed. A hardware control scheme is presented, based on the industrial personal computer and control card PC6401. In order to gain single-axis, precise control of the dental arch generator, we studied the control pulse realization of high-resolution timing. Real-time, closed-loop, synchronous control was applied to the dental arch generator. Experimental control of the dental arch generator and preliminary tooth arrangement were gained by using the multi-manipulator tooth-arrangement robotic system. The dental arch generator can automatically generate a dental arch to fit a patient according to the patient's arch parameters. Repeated positioning accuracy is 0.12 mm for the slipways that drive the dental arch generator. The maximum value of single-point error is 1.83 mm, while the arc-width direction (x axis) is -33.29 mm. A novel system that generates the dental arch has been developed. The traditional method of manually determining the dental arch may soon be replaced by a robot to assist in generating a more individual dental arch. The system can be used to fabricate full dentures and bend orthodontic wires. Copyright © 2012 John Wiley & Sons, Ltd.

Motion planning for multiple robots

NARCIS (Netherlands)

Aronov, B.; Berg, de M.; van der Stappen, A.F.; Svestka, P.; Vleugels, J.M.

1999-01-01

We study the motion-planning problem for pairs and triples of robots operating in a shared workspace containing n obstacles. A standard way to solve such problems is to view the collection of robots as one composite robot, whose number of degrees of freedom is d , the sum of the numbers of degrees

Motion Planning for Omnidirectional Wheeled Mobile Robot by Potential Field Method

Directory of Open Access Journals (Sweden)

Weihao Li

2017-01-01

Full Text Available In this paper, potential field method has been used to navigate a three omnidirectional wheels’ mobile robot and to avoid obstacles. The potential field method is used to overcome the local minima problem and the goals nonreachable with obstacles nearby (GNRON problem. For further consideration, model predictive control (MPC has been used to incorporate motion constraints and make the velocity more realistic and flexible. The proposed method is employed based on the kinematic model and dynamics model of the mobile robot in this paper. To show the performance of proposed control scheme, simulation studies have been carried to perform the motion process of mobile robot in specific workplace.

Compensating for Quasi-periodic Motion in Robotic Radiosurgery

CERN Document Server

Ernst, Floris

2012-01-01

Compensating for Quasi-periodic Motion in Robotic Radiosurgery outlines the techniques needed to accurately track and compensate for respiratory and pulsatory motion during robotic radiosurgery. The algorithms presented within the book aid in the treatment of tumors that move during respiration. In Chapters 1 and 2,  the book introduces the concept of stereotactic body radiation therapy, motion compensation strategies and the clinical state-of-the-art. In Chapters 3 through 5, the author describes and evaluates new methods for motion prediction, for correlating external motion to internal organ motion, and for the evaluation of these algorithms’ output based on an unprecedented amount of real clinical data. Finally, Chapter 6 provides a brief introduction into currently investigated, open questions and further fields of research. Compensating for Quasi-periodic Motion in Robotic Radiosurgery targets researchers working in the related fields of surgical oncology, artificial intelligence, robotics and more. ...

Swarm Robotics with Circular Formation Motion Including Obstacles Avoidance

Directory of Open Access Journals (Sweden)

Nabil M. Hewahi

2017-07-01

Full Text Available The robots science has been developed over the past few years, where robots have become used to accomplish difficult, repetitive or accurate tasks, which are very hard for humans to carry out. In this paper, we propose an algorithm to control the motion of a swarm of robots and make them able to avoid obstacles. The proposed solution is based on forming the robots in circular fashion. A group set of robots consists of multiple groups of robots, each group of robots consists of robots forming a circular shape and each group set is a circular form of robots. The proposed algorithm is concerned with first locating the randomly generated robots in groups and secondly with the swarm robot motion and finally with the swarm obstacle avoidance and swarm reorganization after crossing the obstacle. The proposed algorithm has been simulated with five different obstacles with various numbers of randomly generated robots. The results show that the swarm in the circular form can deal with the obstacles very effectively by passing the obstacles smoothly. The proposed algorithm has been compared with flocking algorithm and it is shown that the circular formation algorithm does not need extensive computation after obstacle avoidance whereas the flocking algorithm needs extensive computation. In addition, the circular formation algorithm maintains every robot in its group after avoiding the obstacles whereas with flocking algorithm does not.

Motion Control Design for an Omnidirectional Mobile Robot Subject to Velocity Constraints

Directory of Open Access Journals (Sweden)

Ollin Peñaloza-Mejía

2015-01-01

Full Text Available A solution to achieve global asymptotic tracking with bounded velocities in an omnidirectional mobile robot is proposed in this paper. It is motivated by the need of having a useful in-practice motion control scheme, which takes into account the physical limits of the velocities. To this end, a passive nonlinear controller is designed and combined with a tracking controller in a negative feedback connection structure. By using Lyapunov theory and passivity tools, global asymptotic tracking with desired bounded velocities is proved. Simulations and experimental results are provided to show the effectiveness of the proposal.

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

Software for Project-Based Learning of Robot Motion Planning

Science.gov (United States)

Moll, Mark; Bordeaux, Janice; Kavraki, Lydia E.

2013-01-01

Motion planning is a core problem in robotics concerned with finding feasible paths for a given robot. Motion planning algorithms perform a search in the high-dimensional continuous space of robot configurations and exemplify many of the core algorithmic concepts of search algorithms and associated data structures. Motion planning algorithms can…

The Motion Path Study of Measuring Robot Based on Variable Universe Fuzzy Control

Directory of Open Access Journals (Sweden)

Ma Guoqing

2017-01-01

Full Text Available For the problem of measuring robot requires a higher positioning, firstly learning about the error overview of the system, analysised the influence of attitude, speed and other factors on systematic errors. Then collected and analyzed the systematic error curve in the track to complete the planning process. The last adding fuzzy control in both cases, by comparing with the original system, can found that the method based on fuzzy control system can significantly reduce the error during the motion.

Reverse control for humanoid robot task recognition.

Science.gov (United States)

Hak, Sovannara; Mansard, Nicolas; Stasse, Olivier; Laumond, Jean Paul

2012-12-01

Efficient methods to perform motion recognition have been developed using statistical tools. Those methods rely on primitive learning in a suitable space, for example, the latent space of the joint angle and/or adequate task spaces. Learned primitives are often sequential: A motion is segmented according to the time axis. When working with a humanoid robot, a motion can be decomposed into parallel subtasks. For example, in a waiter scenario, the robot has to keep some plates horizontal with one of its arms while placing a plate on the table with its free hand. Recognition can thus not be limited to one task per consecutive segment of time. The method presented in this paper takes advantage of the knowledge of what tasks the robot is able to do and how the motion is generated from this set of known controllers, to perform a reverse engineering of an observed motion. This analysis is intended to recognize parallel tasks that have been used to generate a motion. The method relies on the task-function formalism and the projection operation into the null space of a task to decouple the controllers. The approach is successfully applied on a real robot to disambiguate motion in different scenarios where two motions look similar but have different purposes.

Biologically inspired control of humanoid robot arms robust and adaptive approaches

CERN Document Server

Spiers, Adam; Herrmann, Guido

2016-01-01

This book investigates a biologically inspired method of robot arm control, developed with the objective of synthesising human-like motion dynamically, using nonlinear, robust and adaptive control techniques in practical robot systems. The control method caters to a rising interest in humanoid robots and the need for appropriate control schemes to match these systems. Unlike the classic kinematic schemes used in industrial manipulators, the dynamic approaches proposed here promote human-like motion with better exploitation of the robot’s physical structure. This also benefits human-robot interaction. The control schemes proposed in this book are inspired by a wealth of human-motion literature that indicates the drivers of motion to be dynamic, model-based and optimal. Such considerations lend themselves nicely to achievement via nonlinear control techniques without the necessity for extensive and complex biological models. The operational-space method of robot control forms the basis of many of the techniqu...

Development of a 6DOF robotic motion phantom for radiation therapy

International Nuclear Information System (INIS)

Belcher, Andrew H.; Liu, Xinmin; Grelewicz, Zachary; Pearson, Erik; Wiersma, Rodney D.

2014-01-01

Purpose: The use of medical technology capable of tracking patient motion or positioning patients along 6 degree-of-freedom (6DOF) has steadily increased in the field of radiation therapy. However, due to the complex nature of tracking and performing 6DOF motion, it is critical that such technology is properly verified to be operating within specifications in order to ensure patient safety. In this study, a robotic motion phantom is presented that can be programmed to perform highly accurate motion along any X (left–right), Y (superior–inferior), Z (anterior–posterior), pitch (around X), roll (around Y), and yaw (around Z) axes. In addition, highly synchronized motion along all axes can be performed in order to simulate the dynamic motion of a tumor in 6D. The accuracy and reproducibility of this 6D motion were characterized. Methods: An in-house designed and built 6D robotic motion phantom was constructed following the Stewart–Gough parallel kinematics platform archetype. The device was controlled using an inverse kinematics formulation, and precise movements in all 6 degrees-of-freedom (X, Y, Z, pitch, roll, and yaw) were performed, both simultaneously and separately for each degree-of-freedom. Additionally, previously recorded 6D cranial and prostate motions were effectively executed. The robotic phantom movements were verified using a 15 fps 6D infrared marker tracking system and the measured trajectories were compared quantitatively to the intended input trajectories. The workspace, maximum 6D velocity, backlash, and weight load capabilities of the system were also established. Results: Evaluation of the 6D platform demonstrated translational root mean square error (RMSE) values of 0.14, 0.22, and 0.08 mm over 20 mm in X and Y and 10 mm in Z, respectively, and rotational RMSE values of 0.16°, 0.06°, and 0.08° over 10° of pitch, roll, and yaw, respectively. The robotic stage also effectively performed controlled 6D motions, as well as reproduced

Interactive animated displayed of man-controlled and autonomous robots

International Nuclear Information System (INIS)

Crane, C.D. III; Duffy, J.

1986-01-01

An interactive computer graphics program has been developed which allows an operator to more readily control robot motions in two distinct modes; viz., man-controlled and autonomous. In man-controlled mode, the robot is guided by a joystick or similar device. As the robot moves, actual joint angle information is measured and supplied to a graphics system which accurately duplicates the robot motion. Obstacles are placed in the actual and animated workspace and the operator is warned of imminent collisions by sight and sound via the graphics system. Operation of the system in man-controlled mode is shown. In autonomous mode, a collision-free path between specified points is obtained by previewing robot motions on the graphics system. Once a satisfactory path is selected, the path characteristics are transmitted to the actual robot and the motion is executed. The telepresence system developed at the University of Florida has been successful in demonstrating that the concept of controlling a robot manipulator with the aid of an interactive computer graphics system is feasible and practical. The clarity of images coupled with real-time interaction and real-time determination of imminent collision with obstacles has resulted in improved operator performance. Furthermore, the ability for an operator to preview and supervise autonomous operations is a significant attribute when operating in a hazardous environment

Dynamic Modelling and Adaptive Traction Control for Mobile Robots

Directory of Open Access Journals (Sweden)

A. Albagul

2004-09-01

Full Text Available Mobile robots have received a great deal of research in recent years. A significant amount of research has been published in many aspects related to mobile robots. Most of the research is devoted to design and develop some control techniques for robot motion and path planning. A large number of researchers have used kinematic models to develop motion control strategy for mobile robots. Their argument and assumption that these models are valid if the robot has low speed, low acceleration and light load. However, dynamic modelling of mobile robots is very important as they are designed to travel at higher speed and perform heavy duty work. This paper presents and discusses a new approach to develop a dynamic model and control strategy for wheeled mobile robot which I modelled as a rigid body that roles on two wheels and a castor. The motion control strategy consists of two levels. The first level is dealing with the dynamic of the system and denoted as ‘Low’ level controller. The second level is developed to take care of path planning and trajectory generation.

Real-Time Motion Planning and Safe Navigation in Dynamic Multi-Robot Environments

National Research Council Canada - National Science Library

Bruce, James R

2006-01-01

.... While motion planning has been used for high level robot navigation, or limited to semi-static or single-robot domains, it has often been dismissed for the real-time low-level control of agents due...

Development of an assist controller with robot suit HAL for hemiplegic patients using motion data on the unaffected side.

Science.gov (United States)

Kawamoto, Hiroaki; Kandone, Hideki; Sakurai, Takeru; Ariyasu, Ryohei; Ueno, Yukiko; Eguchi, Kiyoshi; Sankai, Yoshiyuki

2014-01-01

Among several characteristics seen in gait of hemiplegic patients after stroke, symmetry is known to be an indicator of the degree of impairment of walking ability. This paper proposes a control method for a wearable type lower limb motion assist robot to realize spontaneous symmetric gait for these individuals. This control method stores the motion of the unaffected limb during swing and then provides motion support on the affected limb during the subsequent swing using the stored pattern to realize symmetric gait based on spontaneous limb swing. This method is implemented on the robot suit HAL (Hybrid Assistive Limbs). Clinical tests were conducted in order to assess the feasibility of the control method. Our case study involved participation of one chronic stroke patient who was not able to flex his right knee. As a result, the walking support for hemiplegic leg provided by the HAL improved the subject's gait symmetry. The feasibility study showed promising basis for the future clinical study.

Discrete time motion model for guiding people in urban areas using multiple robots

OpenAIRE

Garrell Zulueta, Anais; Sanfeliu Cortés, Alberto; Moreno-Noguer, Francesc

2009-01-01

We present a new model for people guidance in urban settings using several mobile robots, that overcomes the limitations of existing approaches, which are either tailored to tightly bounded environments, or based on unrealistic human behaviors. Although the robots motion is controlled by means of a standard particle filter formulation, the novelty of our approach resides in how the environment and human and robot motions are modeled. In particular we define a “Discrete-Time-Motion” model, whi...

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...

Controller design for Robotic hand through Electroencephalogram

OpenAIRE

Pandelidis P.; Kiriazis N.; Orgianelis K.; Koulios N.

2016-01-01

- This paper deals with the designing, the construction and the control of a robotic hand via an electroencephalogram sensor. First a robotic device that is able to mimic a real human hand is constructed. A PID controller is designed in order to improve the performance of the robotic arm for grabbing objects. Furthermore, a novel design approach is presented for controlling the motion of the robotic arm using signals produced from an innovative electroencephalogram sensor that detects the con...

Development of constrained motion control for robot handling of hazardous waste

International Nuclear Information System (INIS)

Starr, G.P.

1993-01-01

Handling and archiving of hazardous waste is an area where automation and robotics can be of significant benefit, by removing the human operator from the workplace and its associated hazards. For reasons of safety, throughput, and reduced setup time, force-controlled robots are well-suited for hazardous materials handling. The focus of this investigation is the development of advanced force control techniques for commercial industrial robots in the surface sampling of hazardous waste containers. Two particular control strategies are considered, (1) preview control, and (2) adaptive control. Preview control uses a sensor which can ''look ahead'' and thereby reduce the effect of surface irregularity on contact force control. Adaptive control allows the robot controller to compensate for changes in the robot characteristics as it changes position, and likewise improves performance. The resulting control algorithms will be applied to a two-dimensional contour-following task using a PUMA robot at the Robotics Research Laboratory at The University of New Mexico. (author) 9 figs., 13 refs

Software for project-based learning of robot motion planning

Science.gov (United States)

Moll, Mark; Bordeaux, Janice; Kavraki, Lydia E.

2013-12-01

Motion planning is a core problem in robotics concerned with finding feasible paths for a given robot. Motion planning algorithms perform a search in the high-dimensional continuous space of robot configurations and exemplify many of the core algorithmic concepts of search algorithms and associated data structures. Motion planning algorithms can be explained in a simplified two-dimensional setting, but this masks many of the subtleties and complexities of the underlying problem. We have developed software for project-based learning of motion planning that enables deep learning. The projects that we have developed allow advanced undergraduate students and graduate students to reflect on the performance of existing textbook algorithms and their own variations on such algorithms. Formative assessment has been conducted at three institutions. The core of the software used for this teaching module is also used within the Robot Operating System, a widely adopted platform by the robotics research community. This allows for transfer of knowledge and skills to robotics research projects involving a large variety robot hardware platforms.

The research on visual industrial robot which adopts fuzzy PID control algorithm

Science.gov (United States)

Feng, Yifei; Lu, Guoping; Yue, Lulin; Jiang, Weifeng; Zhang, Ye

2017-03-01

The control system of six degrees of freedom visual industrial robot based on the control mode of multi-axis motion control cards and PC was researched. For the variable, non-linear characteristics of industrial robot`s servo system, adaptive fuzzy PID controller was adopted. It achieved better control effort. In the vision system, a CCD camera was used to acquire signals and send them to video processing card. After processing, PC controls the six joints` motion by motion control cards. By experiment, manipulator can operate with machine tool and vision system to realize the function of grasp, process and verify. It has influence on the manufacturing of the industrial robot.

Dance notations and robot motion

CERN Document Server

Abe, Naoko

2016-01-01

How and why to write a movement? Who is the writer? Who is the reader? They may be choreographers working with dancers. They may be roboticists programming robots. They may be artists designing cartoons in computer animation. In all such fields the purpose is to express an intention about a dance, a specific motion or an action to perform, in terms of intelligible sequences of elementary movements, as a music score that would be devoted to motion representation. Unfortunately there is no universal language to write a motion. Motion languages live together in a Babel tower populated by biomechanists, dance notators, neuroscientists, computer scientists, choreographers, roboticists. Each community handles its own concepts and speaks its own language. The book accounts for this diversity. Its origin is a unique workshop held at LAAS-CNRS in Toulouse in 2014. Worldwide representatives of various communities met there. Their challenge was to reach a mutual understanding allowing a choreographer to access robotics ...

Remote control and motion coordination of mobile robots

NARCIS (Netherlands)

Alvarez Aguirre, A.

2011-01-01

As robots destined for personal and professional applications advance towards becoming part of our daily lives, the importance and complexity of the control algorithms which regulate them should not be underestimated. This thesis is related to two fields within robotics which are of major importance

Control of a high precision macro-micro robotic manipulator system

International Nuclear Information System (INIS)

Cho, Whang

1997-01-01

A controller for macro-micro robotic manipulator system in which kinematically independent two robotic sub-systems work together to improve the accuracy of the motion is proposed. A nonlinear feedback linearization scheme is employed as basic architecture for the controller and additional formulations about the controller structure are made to assure the robustness of the overall control action and to restrict the motion of micro sub-system close to its nominal position without causing saturation of joint associated with micro-robot. (author)

Control of multiple robots using vision sensors

CERN Document Server

Aranda, Miguel; Sagüés, Carlos

2017-01-01

This monograph introduces novel methods for the control and navigation of mobile robots using multiple-1-d-view models obtained from omni-directional cameras. This approach overcomes field-of-view and robustness limitations, simultaneously enhancing accuracy and simplifying application on real platforms. The authors also address coordinated motion tasks for multiple robots, exploring different system architectures, particularly the use of multiple aerial cameras in driving robot formations on the ground. Again, this has benefits of simplicity, scalability and flexibility. Coverage includes details of: a method for visual robot homing based on a memory of omni-directional images a novel vision-based pose stabilization methodology for non-holonomic ground robots based on sinusoidal-varying control inputs an algorithm to recover a generic motion between two 1-d views and which does not require a third view a novel multi-robot setup where multiple camera-carrying unmanned aerial vehicles are used to observe and c...

Controller design for Robotic hand through Electroencephalogram

Directory of Open Access Journals (Sweden)

Pandelidis P.

2016-01-01

Full Text Available - This paper deals with the designing, the construction and the control of a robotic hand via an electroencephalogram sensor. First a robotic device that is able to mimic a real human hand is constructed. A PID controller is designed in order to improve the performance of the robotic arm for grabbing objects. Furthermore, a novel design approach is presented for controlling the motion of the robotic arm using signals produced from an innovative electroencephalogram sensor that detects the concentration of the brain

Two-legged walking robot prescribed motion on a rough cylinder

Science.gov (United States)

Golubev, Yury; Melkumova, Elena

2018-05-01

The motion of a walking robot with n legs, that ensure the desired motion of the robot body, is described using general dynamics theoretical framework. When each of the robot legs contacts the surface in a single foothold, the momentum and angular momentum theorems yield a system of six differential equations that form a complete description of the robot motion. In the case of two-leg robot (n = 2) the problem of the existence of the solution can be reduced to a system of algebraic inequalities. Using numerical analysis, the classification of footholds positions for different values of the friction coefficient is obtained.

Positional control of space robot manipulator

Science.gov (United States)

Kurochkin, Vladislav; Shymanchuk, Dzmitry

2018-05-01

In this article the mathematical model of a planar space robot manipulator is under study. The space robot manipulator represents a solid body with attached manipulators. The system of equations of motion is determined using the Lagrange's equations. The control problem concerning moving the robot to a given point and return it to a given trajectory in the phase space is solved. Changes of generalized coordinates and necessary control actions are plotted for a specific model.

Alternative Motion Control for Educational Biped BRAT Robots

Directory of Open Access Journals (Sweden)

Levente Barabas

2015-12-01

Full Text Available In this paper an alternative control solution will be proposed for an educational biped BRAT robot by replacing its SSC-32 servomotor controller with an Arduino R3 development board. Also we will be approaching the problem of adapting the existing electronic circuit to the new requirements and proposing a new application by adding an ultrasonic distance sensor in order to increase the versatility of the robot and make it capable to interact with its environment.

Human motion behavior while interacting with an industrial robot.

Science.gov (United States)

Bortot, Dino; Ding, Hao; Antonopolous, Alexandros; Bengler, Klaus

2012-01-01

Human workers and industrial robots both have specific strengths within industrial production. Advantageously they complement each other perfectly, which leads to the development of human-robot interaction (HRI) applications. Bringing humans and robots together in the same workspace may lead to potential collisions. The avoidance of such is a central safety requirement. It can be realized with sundry sensor systems, all of them decelerating the robot when the distance to the human decreases alarmingly and applying the emergency stop, when the distance becomes too small. As a consequence, the efficiency of the overall systems suffers, because the robot has high idle times. Optimized path planning algorithms have to be developed to avoid that. The following study investigates human motion behavior in the proximity of an industrial robot. Three different kinds of encounters between the two entities under three robot speed levels are prompted. A motion tracking system is used to capture the motions. Results show, that humans keep an average distance of about 0,5m to the robot, when the encounter occurs. Approximation of the workbenches is influenced by the robot in ten of 15 cases. Furthermore, an increase of participants' walking velocity with higher robot velocities is observed.

Robot-Arm Dynamic Control by Computer

Science.gov (United States)

Bejczy, Antal K.; Tarn, Tzyh J.; Chen, Yilong J.

1987-01-01

Feedforward and feedback schemes linearize responses to control inputs. Method for control of robot arm based on computed nonlinear feedback and state tranformations to linearize system and decouple robot end-effector motions along each of cartesian axes augmented with optimal scheme for correction of errors in workspace. Major new feature of control method is: optimal error-correction loop directly operates on task level and not on joint-servocontrol level.

Compensation of Wave-Induced Motion and Force Phenomena for Ship-Based High Performance Robotic and Human Amplifying Systems

Energy Technology Data Exchange (ETDEWEB)

Love, LJL

2003-09-24

The decrease in manpower and increase in material handling needs on many Naval vessels provides the motivation to explore the modeling and control of Naval robotic and robotic assistive devices. This report addresses the design, modeling, control and analysis of position and force controlled robotic systems operating on the deck of a moving ship. First we provide background information that quantifies the motion of the ship, both in terms of frequency and amplitude. We then formulate the motion of the ship in terms of homogeneous transforms. This transformation provides a link between the motion of the ship and the base of a manipulator. We model the kinematics of a manipulator as a serial extension of the ship motion. We then show how to use these transforms to formulate the kinetic and potential energy of a general, multi-degree of freedom manipulator moving on a ship. As a demonstration, we consider two examples: a one degree-of-freedom system experiencing three sea states operating in a plane to verify the methodology and a 3 degree of freedom system experiencing all six degrees of ship motion to illustrate the ease of computation and complexity of the solution. The first series of simulations explore the impact wave motion has on tracking performance of a position controlled robot. We provide a preliminary comparison between conventional linear control and Repetitive Learning Control (RLC) and show how fixed time delay RLC breaks down due to the varying nature wave disturbance frequency. Next, we explore the impact wave motion disturbances have on Human Amplification Technology (HAT). We begin with a description of the traditional HAT control methodology. Simulations show that the motion of the base of the robot, due to ship motion, generates disturbances forces reflected to the operator that significantly degrade the positioning accuracy and resolution at higher sea states. As with position-controlled manipulators, augmenting the control with a Repetitive

Stingray-inspired robot with simply actuated intermediate motion

Science.gov (United States)

Neely, Lincoln; Gaiennie, Jack; Noble, Nick; Erickson, Jonathan C.

2016-04-01

Batoids, or rays, utilize unique forms of locomotion that may offer more efficient techniques of motorized propulsion in various marine environments. We present a novel biomimetic engineering design and assembly of a stingray-inspired robot swimmer. The robots locomotion mimics the Dasyatis americana, or southern stingray, whose distinction among rays is its intermediate motion, characterized by sweeping strokes that propagate between 1/2-1 wavelength of the fin profile in the posterior direction. Though oscillatory ( wavelengths) ray-based robots have been created, this project demonstrates new engineering possibilities in what is, to the best of our knowledge, the first intermediately propelled batoid-based robot. The robots fins were made of silicone rubber, cast in a 3-D printed mold, with wingspan of 42 cm (1/2 - 1/5 scale for males and females, respectively, scale of model organism). Two anteriorly placed servomotors per fin were used, all controlled by one wirelessly enabled Arduino microcontroller. Each servomotor oscillated a flexible rod with cylindrical joint, whose frequency, speed, and front-back phase delay were user-programmed over wireless connection. During free-swimming tests, the fin profile developed about 0.8 wavelength, qualifying for successful mimicry of its biological inspiration. The robot satisfactorily maintained straight-line motion, reaching average peak velocity of 9.4+/-1.0 cm/s (0.27-0.03 body lengths/second) at its optimum flapping frequency of 1.4 Hz. This is in the same order of magnitude of speed normalized to body length achieved by others in two recent batoid-based projects. In summary, our robot performed intermediate stingray locomotion with relatively fewer components, which reveals robust potential for innovation of the simple intermediate batoid-based robot swimmer.

Research on Robot Pose Control Technology Based on Kinematics Analysis Model

Science.gov (United States)

Liu, Dalong; Xu, Lijuan

2018-01-01

In order to improve the attitude stability of the robot, proposes an attitude control method of robot based on kinematics analysis model, solve the robot walking posture transformation, grasping and controlling the motion planning problem of robot kinematics. In Cartesian space analytical model, using three axis accelerometer, magnetometer and the three axis gyroscope for the combination of attitude measurement, the gyroscope data from Calman filter, using the four element method for robot attitude angle, according to the centroid of the moving parts of the robot corresponding to obtain stability inertia parameters, using random sampling RRT motion planning method, accurate operation to any position control of space robot, to ensure the end effector along a prescribed trajectory the implementation of attitude control. The accurate positioning of the experiment is taken using MT-R robot as the research object, the test robot. The simulation results show that the proposed method has better robustness, and higher positioning accuracy, and it improves the reliability and safety of robot operation.

Model-Based Design of Brushless DC Motor Control and Motion Control Modelling for RoboCup SSL Robots

OpenAIRE

Li, Xiaotian

2015-01-01

Over the recent years, the RoboCup competition has grown popular and attracted more and more domestic and international universities, and the levels of the teams increase every year. In Small Size League (SSL) competition, besides a good strategy system, the precision of the robots’ actions is also of vital importance in order to achieve high performance. Thus, a highly accurate and stable motion control system is needed to drive the robots to move in accordance with the planned trajectory. C...

Motion and Emotional Behavior Design for Pet Robot Dog

Science.gov (United States)

Cheng, Chi-Tai; Yang, Yu-Ting; Miao, Shih-Heng; Wong, Ching-Chang

A pet robot dog with two ears, one mouth, one facial expression plane, and one vision system is designed and implemented so that it can do some emotional behaviors. Three processors (Inter® Pentium® M 1.0 GHz, an 8-bit processer 8051, and embedded soft-core processer NIOS) are used to control the robot. One camera, one power detector, four touch sensors, and one temperature detector are used to obtain the information of the environment. The designed robot with 20 DOF (degrees of freedom) is able to accomplish the walking motion. A behavior system is built on the implemented pet robot so that it is able to choose a suitable behavior for different environmental situation. From the practical test, we can see that the implemented pet robot dog can do some emotional interaction with the human.

Smart Braid Feedback for the Closed-Loop Control of Soft Robotic Systems.

Science.gov (United States)

Felt, Wyatt; Chin, Khai Yi; Remy, C David

2017-09-01

This article experimentally investigates the potential of using flexible, inductance-based contraction sensors in the closed-loop motion control of soft robots. Accurate motion control remains a highly challenging task for soft robotic systems. Precise models of the actuation dynamics and environmental interactions are often unavailable. This renders open-loop control impossible, while closed-loop control suffers from a lack of suitable feedback. Conventional motion sensors, such as linear or rotary encoders, are difficult to adapt to robots that lack discrete mechanical joints. The rigid nature of these sensors runs contrary to the aspirational benefits of soft systems. As truly soft sensor solutions are still in their infancy, motion control of soft robots has so far relied on laboratory-based sensing systems such as motion capture, electromagnetic (EM) tracking, or Fiber Bragg Gratings. In this article, we used embedded flexible sensors known as Smart Braids to sense the contraction of McKibben muscles through changes in inductance. We evaluated closed-loop control on two systems: a revolute joint and a planar, one degree of freedom continuum manipulator. In the revolute joint, our proposed controller compensated for elasticity in the actuator connections. The Smart Braid feedback allowed motion control with a steady-state root-mean-square (RMS) error of [1.5]°. In the continuum manipulator, Smart Braid feedback enabled tracking of the desired tip angle with a steady-state RMS error of [1.25]°. This work demonstrates that Smart Braid sensors can provide accurate position feedback in closed-loop motion control suitable for field applications of soft robotic systems.

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...

Modeling and Control of Underwater Robotic Systems

Energy Technology Data Exchange (ETDEWEB)

Schjoelberg, I:

1996-12-31

This doctoral thesis describes modeling and control of underwater vehicle-manipulator systems. The thesis also presents a model and a control scheme for a system consisting of a surface vessel connected to an underwater robotic system by means of a slender marine structure. The equations of motion of the underwater vehicle and manipulator are described and the system kinematics and properties presented. Feedback linearization technique is applied to the system and evaluated through a simulation study. Passivity-based controllers for vehicle and manipulator control are presented. Stability of the closed loop system is proved and simulation results are given. The equation of motion for lateral motion of a cable/riser system connected to a surface vessel at the top end and to a thruster at the bottom end is described and stability analysis and simulations are presented. The equations of motion in 3 degrees of freedom of the cable/riser, surface vessel and robotic system are given. Stability analysis of the total system with PD-controllers is presented. 47 refs., 32 figs., 7 tabs.

Snake Robots Modelling, Mechatronics, and Control

CERN Document Server

Liljebäck, Pål; Stavdahl, Øyvind; Gravdahl, Jan Tommy

2013-01-01

Snake Robots is a novel treatment of theoretical and practical topics related to snake robots: robotic mechanisms designed to move like biological snakes and able to operate in challenging environments in which human presence is either undesirable or impossible. Future applications of such robots include search and rescue, inspection and maintenance, and subsea operations. Locomotion in unstructured environments is a focus for this book. The text targets the disparate muddle of approaches to modelling, development and control of snake robots in current literature, giving a unified presentation of recent research results on snake robot locomotion to increase the reader’s basic understanding of these mechanisms and their motion dynamics and clarify the state of the art in the field. The book is a complete treatment of snake robotics, with topics ranging from mathematical modelling techniques, through mechatronic design and implementation, to control design strategies. The development of two snake robots is de...

Planning of motion strategy for hexapod robot using biogeography based optimization

Directory of Open Access Journals (Sweden)

Hayder Mahdi Abdulridha

2017-08-01

Full Text Available The necessity to utilize the usage of the robot cannot be denied since there are a lot of natural disasters occur around the world, the robot can reach places where humans cannot reach. Hexapod robotic is one of the robots utilized in this case due to its balance and versatility at some stage in the movement on any kind of floor. In this project the explanation of using software and hardware Arduino microcontroller is used to control of such a hexapod. The output signal from Arduino for controlling leg's joint angular position such as a pulse called Pulse Width Modulation (PWM. Also Arduino programmed to create the sequence of motion for six legs. The second part of project is about controlling hexapod to avoid hitches and tracking the wall by using PID controller. Tuning of the PID processes based on Biogeography Based Optimization(BBO need to keep the connection between PC and hexapod, because the BBO was written by Matlab. The experimental results using BBO to optimize the PID controller parameters of hexapod robot show the efficiency of this technique in the adaptation of controller.

Rough terrain motion planning for actively reconfigurable mobile robots

International Nuclear Information System (INIS)

Brunner, Michael

2015-01-01

In the aftermath of the Tohoku earthquake and the nuclear meltdown at the power plant of Fukushima Daiichi in 2011, reconfigurable robots like the iRobot Packbot were deployed. Instead of humans, the robots were used to investigate contaminated areas. Other incidents are the two major earthquakes in Northern Italy in May 2012. Besides many casualties, a large number of historical buildings was severely damaged. Due to the imminent danger of collapse, it was too dangerous for rescue personnel to enter many of the buildings. Therefore, the sites were inspected by reconfigurable robots, which are able to traverse the rubble and debris of the partially destroyed buildings. This thesis develops a navigation system enabling wheeled and tracked robots to safely traverse rough terrain and challenging structures. It consists of a planning mechanism and a controller. The focus of this thesis, however, is on the contribution to motion planning. The planning scheme employs a hierarchical approach to motion planning for actively reconfigurable robots in rough environments. Using a map of the environment the algorithm estimates the traversability under the consideration of uncertainties. Based on this analysis, an initial path search determines an approximate solution with respect to the robot's operating limits.Subsequently, a detailed planning step refines the initial path where it is required. The refinement step considers the robot's actuators and stability in addition to the quantities of the first search. Determining the robot-terrain interaction is very important in rough terrain. This thesis presents two path refinement approaches: a deterministic and a randomized approach. The experimental evaluation investigates the separate components of the planning scheme, the robot-terrain interaction for instance.In simulation as well as in real world experiments the evaluation demonstrates the necessity of such a planning algorithm in rough terrain and it provides

Rough terrain motion planning for actively reconfigurable mobile robots

Energy Technology Data Exchange (ETDEWEB)

Brunner, Michael

2015-02-05

In the aftermath of the Tohoku earthquake and the nuclear meltdown at the power plant of Fukushima Daiichi in 2011, reconfigurable robots like the iRobot Packbot were deployed. Instead of humans, the robots were used to investigate contaminated areas. Other incidents are the two major earthquakes in Northern Italy in May 2012. Besides many casualties, a large number of historical buildings was severely damaged. Due to the imminent danger of collapse, it was too dangerous for rescue personnel to enter many of the buildings. Therefore, the sites were inspected by reconfigurable robots, which are able to traverse the rubble and debris of the partially destroyed buildings. This thesis develops a navigation system enabling wheeled and tracked robots to safely traverse rough terrain and challenging structures. It consists of a planning mechanism and a controller. The focus of this thesis, however, is on the contribution to motion planning. The planning scheme employs a hierarchical approach to motion planning for actively reconfigurable robots in rough environments. Using a map of the environment the algorithm estimates the traversability under the consideration of uncertainties. Based on this analysis, an initial path search determines an approximate solution with respect to the robot's operating limits.Subsequently, a detailed planning step refines the initial path where it is required. The refinement step considers the robot's actuators and stability in addition to the quantities of the first search. Determining the robot-terrain interaction is very important in rough terrain. This thesis presents two path refinement approaches: a deterministic and a randomized approach. The experimental evaluation investigates the separate components of the planning scheme, the robot-terrain interaction for instance.In simulation as well as in real world experiments the evaluation demonstrates the necessity of such a planning algorithm in rough terrain and it provides

Emulating a robotic manipulator arm with an hybrid motion-control system

International Nuclear Information System (INIS)

Aragón-González, G; León-Galicia, A; Noriega-Hernández, M; Salazar-Hueta, A

2015-01-01

A motion control system with four and 1/2 degrees of freedom, designed to move small objects within a 0.25 m3 space, parallel to a horizontal table, with high speed and performance similar to a robotic manipulator arm was built. The machine employs several actuators and control devices. Its main characteristic is to incorporate a servomotor, steeper motors, electromechanical and fluid power actuators and diverse control resources. A group of actuators arranged on a spherical coordinates system is attached to the servomotor platform. A linear pneumatic actuator with an angular grip provides the radial extension and load clamping capacity. Seven inductive proximity sensors and one encoder provide feedback, for operating the actuators under closed loop conditions. Communication between the sensors and control devices is organized by a PLC. A touch screen allows governing the system remotely, easily and interactively, without knowing the specific programming language of each control component. The graphic environment on the touch screen guides the user to design and store control programs, establishing coordinated automatic routines for moving objects in space, simulation and implementation of industrial positioning or machining processes

Monitoring and Controlling an Underwater Robotic Arm

Science.gov (United States)

Haas, John; Todd, Brian Keith; Woodcock, Larry; Robinson, Fred M.

2009-01-01

The SSRMS Module 1 software is part of a system for monitoring an adaptive, closed-loop control of the motions of a robotic arm in NASA s Neutral Buoyancy Laboratory, where buoyancy in a pool of water is used to simulate the weightlessness of outer space. This software is so named because the robot arm is a replica of the Space Shuttle Remote Manipulator System (SSRMS). This software is distributed, running on remote joint processors (RJPs), each of which is mounted in a hydraulic actuator comprising the joint of the robotic arm and communicating with a poolside processor denoted the Direct Control Rack (DCR). Each RJP executes the feedback joint-motion control algorithm for its joint and communicates with the DCR. The DCR receives joint-angular-velocity commands either locally from an operator or remotely from computers that simulate the flight like SSRMS and perform coordinated motion calculations based on hand-controller inputs. The received commands are checked for validity before they are transmitted to the RJPs. The DCR software generates a display of the statuses of the RJPs for the DCR operator and can shut down the hydraulic pump when excessive joint-angle error or failure of a RJP is detected.

Interactive robot control system and method of use

Science.gov (United States)

Sanders, Adam M. (Inventor); Reiland, Matthew J. (Inventor); Abdallah, Muhammad E. (Inventor); Linn, Douglas Martin (Inventor); Platt, Robert (Inventor)

2012-01-01

A robotic system includes a robot having joints, actuators, and sensors, and a distributed controller. The controller includes command-level controller, embedded joint-level controllers each controlling a respective joint, and a joint coordination-level controller coordinating motion of the joints. A central data library (CDL) centralizes all control and feedback data, and a user interface displays a status of each joint, actuator, and sensor using the CDL. A parameterized action sequence has a hierarchy of linked events, and allows the control data to be modified in real time. A method of controlling the robot includes transmitting control data through the various levels of the controller, routing all control and feedback data to the CDL, and displaying status and operation of the robot using the CDL. The parameterized action sequences are generated for execution by the robot, and a hierarchy of linked events is created within the sequence.

Application oriented programming and control of industrial robots

International Nuclear Information System (INIS)

Nilsson, Klas.

1992-07-01

Efficient use of industrial robots requires a strong interplay between user level commands, the motion control system, and external equipment. It should also be possible for an experienced application engineer to tailor the motion control to a specific application in a convenient way, instead of deficient utilization of the device or tricky user programming which is often the case today. A layered software architecture has been designed based on an application oriented view, considering typical hardware and software constraints. The top layers or the architecture support improved integration of off-line programming with interactive teach-in programming. The proposed solution is based on a transformation of robot programs between an on-line and an off-line representation. A central part of the architecture is an intermediate software layer, allowing the experienced user to introduce application specific motion primitives, on top of the motion control system. Flexibility during system configuration combined with computing efficiency and performance at run-time is of major importance. The solution is based on so called actions, which are methods to be passed between different software layers. Such methods can be specification of nonlinear control parameters, application specific control strategies, or treatment of external sensor signals. The actions can be implemented efficiently even in the multiprocessor case by using relocatable executable pieces of code generated from a special cross-compilation strategy. The lowest layers, comprising the motion control, have to be efficient and still fit in with the upper layers. In these layers, software solutions include an external sensor interface and a concept of motion pipelining allowing sensor based motions to be partly computed in advance. An experimental platform, built around commercially available robots, has been developed to verify the proposed solutions. (au)

TH-EF-BRB-08: Robotic Motion Compensation for Radiation Therapy: A 6DOF Phantom Study

Energy Technology Data Exchange (ETDEWEB)

Belcher, AH; Liu, X; Wiersma, R [The University of Chicago, Chicago, IL (United States)

2016-06-15

Purpose: The high accuracy of frame-based stereotactic radiosurgery (SRS), which uses a rigid frame fixed to the patient’s skull, is offset by potential drawbacks of poor patient compliance and clinical workflow restrictions. Recent research into frameless SRS has so far resulted in reduced accuracy. In this study, we investigate the use of a novel 6 degree-of-freedom (6DOF) robotic head motion cancellation system that continuously detects and compensates for patient head motions during a SRS delivery. This approach has the potential to reduce invasiveness while still achieving accuracies better or equal to traditional frame-based SRS. Methods: A 6DOF parallel kinematics robotics stage was constructed, and controlled using an inverse kinematics-based motion compensation algorithm. A 6DOF stereoscopic infrared (IR) marker tracking system was used to monitor real-time motions at sub-millimeter and sub-degree levels. A novel 6DOF calibration technique was first applied to properly orient the camera coordinate frame to match that of the LINAC and robotic control frames. Simulated head motions were measured by the system, and the robotic stage responded to these 6DOF motions automatically, returning the reflective marker coordinate frame to its original position. Results: After the motions were introduced to the system in the phantom-based study, the robotic stage automatically and rapidly returned the phantom to LINAC isocenter. When errors exceeded the compensation lower threshold of 0.25 mm or 0.25 degrees, the system registered the 6DOF error and generated a cancellation trajectory. The system responded in less than 0.5 seconds and returned all axes to less than 0.1 mm and 0.1 degree after the 6DOF compensation was performed. Conclusion: The 6DOF real-time motion cancellation system was found to be effective at compensating for translational and rotational motions to current SRS requirements. This system can improve frameless SRS by automatically returning

TH-EF-BRB-08: Robotic Motion Compensation for Radiation Therapy: A 6DOF Phantom Study

International Nuclear Information System (INIS)

Belcher, AH; Liu, X; Wiersma, R

2016-01-01

Purpose: The high accuracy of frame-based stereotactic radiosurgery (SRS), which uses a rigid frame fixed to the patient’s skull, is offset by potential drawbacks of poor patient compliance and clinical workflow restrictions. Recent research into frameless SRS has so far resulted in reduced accuracy. In this study, we investigate the use of a novel 6 degree-of-freedom (6DOF) robotic head motion cancellation system that continuously detects and compensates for patient head motions during a SRS delivery. This approach has the potential to reduce invasiveness while still achieving accuracies better or equal to traditional frame-based SRS. Methods: A 6DOF parallel kinematics robotics stage was constructed, and controlled using an inverse kinematics-based motion compensation algorithm. A 6DOF stereoscopic infrared (IR) marker tracking system was used to monitor real-time motions at sub-millimeter and sub-degree levels. A novel 6DOF calibration technique was first applied to properly orient the camera coordinate frame to match that of the LINAC and robotic control frames. Simulated head motions were measured by the system, and the robotic stage responded to these 6DOF motions automatically, returning the reflective marker coordinate frame to its original position. Results: After the motions were introduced to the system in the phantom-based study, the robotic stage automatically and rapidly returned the phantom to LINAC isocenter. When errors exceeded the compensation lower threshold of 0.25 mm or 0.25 degrees, the system registered the 6DOF error and generated a cancellation trajectory. The system responded in less than 0.5 seconds and returned all axes to less than 0.1 mm and 0.1 degree after the 6DOF compensation was performed. Conclusion: The 6DOF real-time motion cancellation system was found to be effective at compensating for translational and rotational motions to current SRS requirements. This system can improve frameless SRS by automatically returning

Analyzing the effects of human-aware motion planning on close-proximity human-robot collaboration.

Science.gov (United States)

Lasota, Przemyslaw A; Shah, Julie A

2015-02-01

The objective of this work was to examine human response to motion-level robot adaptation to determine its effect on team fluency, human satisfaction, and perceived safety and comfort. The evaluation of human response to adaptive robotic assistants has been limited, particularly in the realm of motion-level adaptation. The lack of true human-in-the-loop evaluation has made it impossible to determine whether such adaptation would lead to efficient and satisfying human-robot interaction. We conducted an experiment in which participants worked with a robot to perform a collaborative task. Participants worked with an adaptive robot incorporating human-aware motion planning and with a baseline robot using shortest-path motions. Team fluency was evaluated through a set of quantitative metrics, and human satisfaction and perceived safety and comfort were evaluated through questionnaires. When working with the adaptive robot, participants completed the task 5.57% faster, with 19.9% more concurrent motion, 2.96% less human idle time, 17.3% less robot idle time, and a 15.1% greater separation distance. Questionnaire responses indicated that participants felt safer and more comfortable when working with an adaptive robot and were more satisfied with it as a teammate than with the standard robot. People respond well to motion-level robot adaptation, and significant benefits can be achieved from its use in terms of both human-robot team fluency and human worker satisfaction. Our conclusion supports the development of technologies that could be used to implement human-aware motion planning in collaborative robots and the use of this technique for close-proximity human-robot collaboration.

Control of a Quadcopter Aerial Robot Using Optic Flow Sensing

Science.gov (United States)

Hurd, Michael Brandon

This thesis focuses on the motion control of a custom-built quadcopter aerial robot using optic flow sensing. Optic flow sensing is a vision-based approach that can provide a robot the ability to fly in global positioning system (GPS) denied environments, such as indoor environments. In this work, optic flow sensors are used to stabilize the motion of quadcopter robot, where an optic flow algorithm is applied to provide odometry measurements to the quadcopter's central processing unit to monitor the flight heading. The optic-flow sensor and algorithm are capable of gathering and processing the images at 250 frames/sec, and the sensor package weighs 2.5 g and has a footprint of 6 cm2 in area. The odometry value from the optic flow sensor is then used a feedback information in a simple proportional-integral-derivative (PID) controller on the quadcopter. Experimental results are presented to demonstrate the effectiveness of using optic flow for controlling the motion of the quadcopter aerial robot. The technique presented herein can be applied to different types of aerial robotic systems or unmanned aerial vehicles (UAVs), as well as unmanned ground vehicles (UGV).

An FPGA Implementation of a Robot Control System with an Integrated 3D Vision System

Directory of Open Access Journals (Sweden)

Yi-Ting Chen

2015-05-01

Full Text Available Robot decision making and motion control are commonly based on visual information in various applications. Position-based visual servo is a technique for vision-based robot control, which operates in the 3D workspace, uses real-time image processing to perform tasks of feature extraction, and returns the pose of the object for positioning control. In order to handle the computational burden at the vision sensor feedback, we design a FPGA-based motion-vision integrated system that employs dedicated hardware circuits for processing vision processing and motion control functions. This research conducts a preliminary study to explore the integration of 3D vision and robot motion control system design based on a single field programmable gate array (FPGA chip. The implemented motion-vision embedded system performs the following functions: filtering, image statistics, binary morphology, binary object analysis, object 3D position calculation, robot inverse kinematics, velocity profile generation, feedback counting, and multiple-axes position feedback control.

Transputer Control of Hydraulic Actuators and Robots

DEFF Research Database (Denmark)

Conrad, Finn

1996-01-01

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

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...

Range-Space Predictive Control for Optimal Robot Motion

Czech Academy of Sciences Publication Activity Database

Belda, Květoslav; Böhm, Josef

2008-01-01

Roč. 1, č. 1 (2008), s. 1-7 ISSN 1998-0140 R&D Projects: GA ČR GP102/06/P275 Institutional research plan: CEZ:AV0Z10750506 Keywords : Accurate manipulation * Industrial robotics * Predictive control * Range-space control Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/historie/belda-0305644.pdf

Patient-Centered Robot-Aided Passive Neurorehabilitation Exercise Based on Safety-Motion Decision-Making Mechanism

Directory of Open Access Journals (Sweden)

Lizheng Pan

2017-01-01

Full Text Available Safety is one of the crucial issues for robot-aided neurorehabilitation exercise. When it comes to the passive rehabilitation training for stroke patients, the existing control strategies are usually just based on position control to carry out the training, and the patient is out of the controller. However, to some extent, the patient should be taken as a “cooperator” of the training activity, and the movement speed and range of the training movement should be dynamically regulated according to the internal or external state of the subject, just as what the therapist does in clinical therapy. This research presents a novel motion control strategy for patient-centered robot-aided passive neurorehabilitation exercise from the point of the safety. The safety-motion decision-making mechanism is developed to online observe and assess the physical state of training impaired-limb and motion performances and regulate the training parameters (motion speed and training rage, ensuring the safety of the supplied rehabilitation exercise. Meanwhile, position-based impedance control is employed to realize the trajectory tracking motion with interactive compliance. Functional experiments and clinical experiments are investigated with a healthy adult and four recruited stroke patients, respectively. The two types of experimental results demonstrate that the suggested control strategy not only serves with safety-motion training but also presents rehabilitation efficacy.

Analyzing the Effects of Human-Aware Motion Planning on Close-Proximity Human–Robot Collaboration

Science.gov (United States)

Shah, Julie A.

2015-01-01

Objective: The objective of this work was to examine human response to motion-level robot adaptation to determine its effect on team fluency, human satisfaction, and perceived safety and comfort. Background: The evaluation of human response to adaptive robotic assistants has been limited, particularly in the realm of motion-level adaptation. The lack of true human-in-the-loop evaluation has made it impossible to determine whether such adaptation would lead to efficient and satisfying human–robot interaction. Method: We conducted an experiment in which participants worked with a robot to perform a collaborative task. Participants worked with an adaptive robot incorporating human-aware motion planning and with a baseline robot using shortest-path motions. Team fluency was evaluated through a set of quantitative metrics, and human satisfaction and perceived safety and comfort were evaluated through questionnaires. Results: When working with the adaptive robot, participants completed the task 5.57% faster, with 19.9% more concurrent motion, 2.96% less human idle time, 17.3% less robot idle time, and a 15.1% greater separation distance. Questionnaire responses indicated that participants felt safer and more comfortable when working with an adaptive robot and were more satisfied with it as a teammate than with the standard robot. Conclusion: People respond well to motion-level robot adaptation, and significant benefits can be achieved from its use in terms of both human–robot team fluency and human worker satisfaction. Application: Our conclusion supports the development of technologies that could be used to implement human-aware motion planning in collaborative robots and the use of this technique for close-proximity human–robot collaboration. PMID:25790568

Experimentally supported control design for a direct drive robot

NARCIS (Netherlands)

Kostic, D.; Jager, de A.G.; Steinbuch, M.

2002-01-01

We promote the idea of an experimentally supported control design as a successful way to achieve accurate tracking of reference robot motions, under disturbance conditions and given the uncertainties arising from modeling errors. The Hinf robust control theory is used for design of motion

Robotic real-time translational and rotational head motion correction during frameless stereotactic radiosurgery

Energy Technology Data Exchange (ETDEWEB)

Liu, Xinmin; Belcher, Andrew H.; Grelewicz, Zachary; Wiersma, Rodney D., E-mail: rwiersma@uchicago.edu [Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, Illinois 60637 (United States)

2015-06-15

Purpose: To develop a control system to correct both translational and rotational head motion deviations in real-time during frameless stereotactic radiosurgery (SRS). Methods: A novel feedback control with a feed-forward algorithm was utilized to correct for the coupling of translation and rotation present in serial kinematic robotic systems. Input parameters for the algorithm include the real-time 6DOF target position, the frame pitch pivot point to target distance constant, and the translational and angular Linac beam off (gating) tolerance constants for patient safety. Testing of the algorithm was done using a 4D (XY Z + pitch) robotic stage, an infrared head position sensing unit and a control computer. The measured head position signal was processed and a resulting command was sent to the interface of a four-axis motor controller, through which four stepper motors were driven to perform motion compensation. Results: The control of the translation of a brain target was decoupled with the control of the rotation. For a phantom study, the corrected position was within a translational displacement of 0.35 mm and a pitch displacement of 0.15° 100% of the time. For a volunteer study, the corrected position was within displacements of 0.4 mm and 0.2° over 98.5% of the time, while it was 10.7% without correction. Conclusions: The authors report a control design approach for both translational and rotational head motion correction. The experiments demonstrated that control performance of the 4D robotic stage meets the submillimeter and subdegree accuracy required by SRS.

Robotic real-time translational and rotational head motion correction during frameless stereotactic radiosurgery

International Nuclear Information System (INIS)

Liu, Xinmin; Belcher, Andrew H.; Grelewicz, Zachary; Wiersma, Rodney D.

2015-01-01

Purpose: To develop a control system to correct both translational and rotational head motion deviations in real-time during frameless stereotactic radiosurgery (SRS). Methods: A novel feedback control with a feed-forward algorithm was utilized to correct for the coupling of translation and rotation present in serial kinematic robotic systems. Input parameters for the algorithm include the real-time 6DOF target position, the frame pitch pivot point to target distance constant, and the translational and angular Linac beam off (gating) tolerance constants for patient safety. Testing of the algorithm was done using a 4D (XY Z + pitch) robotic stage, an infrared head position sensing unit and a control computer. The measured head position signal was processed and a resulting command was sent to the interface of a four-axis motor controller, through which four stepper motors were driven to perform motion compensation. Results: The control of the translation of a brain target was decoupled with the control of the rotation. For a phantom study, the corrected position was within a translational displacement of 0.35 mm and a pitch displacement of 0.15° 100% of the time. For a volunteer study, the corrected position was within displacements of 0.4 mm and 0.2° over 98.5% of the time, while it was 10.7% without correction. Conclusions: The authors report a control design approach for both translational and rotational head motion correction. The experiments demonstrated that control performance of the 4D robotic stage meets the submillimeter and subdegree accuracy required by SRS

Efficient control of mechatronic systems in dynamic motion tasks

Directory of Open Access Journals (Sweden)

Despotova Desislava

2018-01-01

Full Text Available Robots and powered exoskeletons have often complex and non-linear dynamics due to friction, elasticity, and changing load. The proposed study addresses various-type robots that have to perform dynamic point-to-point motion tasks (PTPMT. The performance demands are for faster motion, higher positioning accuracy, and lower energy consumption. With given motion task, it is of primary importance to study the structure and controllability of the corresponding controlled system. The following natural decentralized controllability condition is assumed: the signs of any control input and the corresponding output (the acceleration are the same, at least when the control input is at its maximum absolute value. Then we find explicit necessary and sufficient conditions on the control transfer matrix that can guarantee robust controllability in the face of arbitrary, but bounded disturbances. Further on, we propose a generic optimisation approach for control learning synthesis of various type robotic systems in PTPMT. Our procedure for iterative learning control (LC has the following main steps: (1 choose a set of appropriate test control functions; (2 define the most relevant input-output pairs; and (3 solve shooting equations and perform control parameter optimisation. We will give several examples to explain our controllability and optimisation concepts.

Automatic Motion Generation for Robotic Milling Optimizing Stiffness with Sample-Based Planning

Directory of Open Access Journals (Sweden)

Julian Ricardo Diaz Posada

2017-01-01

Full Text Available Optimal and intuitive robotic machining is still a challenge. One of the main reasons for this is the lack of robot stiffness, which is also dependent on the robot positioning in the Cartesian space. To make up for this deficiency and with the aim of increasing robot machining accuracy, this contribution describes a solution approach for optimizing the stiffness over a desired milling path using the free degree of freedom of the machining process. The optimal motion is computed based on the semantic and mathematical interpretation of the manufacturing process modeled on its components: product, process and resource; and by configuring automatically a sample-based motion problem and the transition-based rapid-random tree algorithm for computing an optimal motion. The approach is simulated on a CAM software for a machining path revealing its functionality and outlining future potentials for the optimal motion generation for robotic machining processes.

Path-Constrained Motion Planning for Robotics Based on Kinematic Constraints

NARCIS (Netherlands)

Dijk, van N.J.M.; Wouw, van de N.; Pancras, W.C.M.; Nijmeijer, H.

2007-01-01

Common robotic tracking tasks consist of motions along predefined paths. The design of time-optimal path-constrained trajectories for robotic applications is discussed in this paper. To increase industrial applicability, the proposed method accounts for robot kinematics together with actuator

Anthropomorphic Robot Design and User Interaction Associated with Motion

Science.gov (United States)

Ellis, Stephen R.

2016-01-01

Though in its original concept a robot was conceived to have some human-like shape, most robots now in use have specific industrial purposes and do not closely resemble humans. Nevertheless, robots that resemble human form in some way have continued to be introduced. They are called anthropomorphic robots. The fact that the user interface to all robots is now highly mediated means that the form of the user interface is not necessarily connected to the robots form, human or otherwise. Consequently, the unique way the design of anthropomorphic robots affects their user interaction is through their general appearance and the way they move. These robots human-like appearance acts as a kind of generalized predictor that gives its operators, and those with whom they may directly work, the expectation that they will behave to some extent like a human. This expectation is especially prominent for interactions with social robots, which are built to enhance it. Often interaction with them may be mainly cognitive because they are not necessarily kinematically intricate enough for complex physical interaction. Their body movement, for example, may be limited to simple wheeled locomotion. An anthropomorphic robot with human form, however, can be kinematically complex and designed, for example, to reproduce the details of human limb, torso, and head movement. Because of the mediated nature of robot control, there remains in general no necessary connection between the specific form of user interface and the anthropomorphic form of the robot. But their anthropomorphic kinematics and dynamics imply that the impact of their design shows up in the way the robot moves. The central finding of this report is that the control of this motion is a basic design element through which the anthropomorphic form can affect user interaction. In particular, designers of anthropomorphic robots can take advantage of the inherent human-like movement to 1) improve the users direct manual control over

Control of articulated snake robot under dynamic active constraints.

Science.gov (United States)

Kwok, Ka-Wai; Vitiello, Valentina; Yang, Guang-Zhong

2010-01-01

Flexible, ergonomically enhanced surgical robots have important applications to transluminal endoscopic surgery, for which path-following and dynamic shape conformance are essential. In this paper, kinematic control of a snake robot for motion stabilisation under dynamic active constraints is addressed. The main objective is to enable the robot to track the visual target accurately and steadily on deforming tissue whilst conforming to pre-defined anatomical constraints. The motion tracking can also be augmented with manual control. By taking into account the physical limits in terms of maximum frequency response of the system (manifested as a delay between the input of the manipulator and the movement of the end-effector), we show the importance of visual-motor synchronisation for performing accurate smooth pursuit movements. Detailed user experiments are performed to demonstrate the practical value of the proposed control mechanism.

EMBEDDED CONTROL SYSTEM FOR MOBILE ROBOTS WITH DIFFERENTIAL DRIVE

Directory of Open Access Journals (Sweden)

Michal KOPČÍK

2017-09-01

Full Text Available This article deals with design and implementation of control system for mobile robots with differential drive using embedded system. This designed embedded system consists of single control board featuring ARM based microcontroller which control the peripherals in real time and perform all low-level motion control. Designed embedded system can be easily expanded with additional sensors, actuators or control units to enhance applicability of mobile robot. Designed embedded system also features build-in communication module, which can be used for data for data acquisition and control of the mobile robot. Control board was implemented on two different types of mobile robots with differential drive, one of which was wheeled and other was tracked. These mobile robots serve as testing platform for Fault Detection and Isolation using hardware and analytical redundancy using Multisensor Data Fusion based on Kalman filters.

Method for Collision Avoidance Motion Coordination of Multiple Mobile Robots Using Central Observation

Energy Technology Data Exchange (ETDEWEB)

Ko, N.Y.; Seo, D.J. [Chosun University, Kwangju (Korea)

2003-04-01

This paper presents a new method driving multiple robots to their goal position without collision. Each robot adjusts its motion based on the information on the goal locations, velocity, and position of the robot and the velocity and position of the other robots. To consider the movement of the robots in a work area, we adopt the concept of avoidability measure. The avoidability measure figures the degree of how easily a robot can avoid other robots considering the following factors: the distance from the robot to the other robots, velocity of the robot and the other robots. To implement the concept in moving robot avoidance, relative distance between the robots is derived. Our method combines the relative distance with an artificial potential field method. The proposed method is simulated for several cases. The results show that the proposed method steers robots to open space anticipating the approach of other robots. In contrast, the usual potential field method sometimes fails preventing collision or causes hasty motion, because it initiates avoidance motion later than the proposed method. The proposed method can be used to move robots in a robot soccer team to their appropriate position without collision as fast as possible. (author). 21 refs., 10 figs., 13 tabs.

Predicting the Motions and Forces of Wearable Robotic Systems Using Optimal Control

Directory of Open Access Journals (Sweden)

Matthew Millard

2017-08-01

Full Text Available Wearable robotic systems are being developed to prevent injury to the low back. Designing a wearable robotic system is challenging because it is difficult to predict how the exoskeleton will affect the movement of the wearer. To aid the design of exoskeletons, we formulate and numerically solve an optimal control problem (OCP to predict the movements and forces of a person as they lift a 15 kg box from the ground both without (human-only OCP and with (with-exo OCP the aid of an exoskeleton. We model the human body as a sagittal-plane multibody system that is actuated by agonist and antagonist pairs of muscle torque generators (MTGs at each joint. Using the literature as a guide, we have derived a set of MTGs that capture the active torque–angle, passive torque–angle, and torque–velocity characteristics of the flexor and extensor groups surrounding the hip, knee, ankle, lumbar spine, shoulder, elbow, and wrist. Uniquely, these MTGs are continuous to the second derivative and so are compatible with gradient-based optimization. The exoskeleton is modeled as a rigid-body mechanism that is actuated by a motor at the hip and the lumbar spine and is coupled to the wearer through kinematic constraints. We evaluate our results by comparing our predictions with experimental recordings of a human subject. Our results indicate that the predicted peak lumbar-flexion angles and extension torques of the human-only OCP are within the range reported in the literature. The results of the with-exo OCP indicate that the exoskeleton motors should provide relatively little support during the descent to the box but apply a substantial amount of support during the ascent phase. The support provided by the lumbar motor is similar in shape to the net moment generated at the L5/S1 joint by the body; however, the support of the hip motor is more complex because it is coupled to the passive forces that are being generated by the hip extensors of the human subject

Whole-Body Motion Planning for Humanoid Robots by Specifying Via-Points

Directory of Open Access Journals (Sweden)

ChangHyun Sung

2013-07-01

Full Text Available We design a framework about the planning of whole body motion for humanoid robots. Motion planning with various constraints is essential to success the task. In this research, we propose a motion planning method corresponding to various conditions for achieving the task. We specify some via-points to deal with the conditions for target achievement depending on various constraints. Together with certain constraints including task accomplishment, the via-point representation plays a crucial role in the optimization process of our method. Furthermore, the via-points as the optimization parameters are related to some physical conditions. We applied this method to generate the kicking motion of a humanoid robot HOAP-3. We have confirmed that the robot was able to complete the task of kicking a ball over an obstacle into a goal in addition to changing conditions of the location of a ball. These results show that the proposed motion planning method using via-point representation can increase articulation of the motion.

Design and Implementation of an Assistive Controller for Rehabilitation Robotic Systems

Directory of Open Access Journals (Sweden)

Duygun Erol

2007-09-01

Full Text Available The goal of our research is to develop an assistive controller for robotic rehabilitation of the upper extremity after stroke. The controller is used to provide robotic assistance to participants to help them to track a desired motion trajectory required for the rehabilitation task in an accurate and concentrated manner. This rehabilitation task is designed to ensure concentrated repetitive motion that requires cognitive processing. Experimental results on unimpaired participants are presented to demonstrate the effectiveness and feasibility of the proposed controller.

INTEGRATED ROBOT-HUMAN CONTROL IN MINING OPERATIONS

Energy Technology Data Exchange (ETDEWEB)

George Danko

2006-04-01

This report describes the results of the 2nd year of a research project on the implementation of a novel human-robot control system for hydraulic machinery. Sensor and valve re-calibration experiments were conducted to improve open loop machine control. A Cartesian control example was tested both in simulation and on the machine; the results are discussed in detail. The machine tests included open-loop as well as closed-loop motion control. Both methods worked reasonably well, due to the high-quality electro-hydraulic valves used on the experimental machine. Experiments on 3-D analysis of the bucket trajectory using marker tracking software are also presented with the results obtained. Open-loop control is robustly stable and free of short-term dynamic problems, but it allows for drifting away from the desired motion kinematics of the machine. A novel, closed-loop control adjustment provides a remedy, while retaining much of the advantages of the open-loop control based on kinematics transformation. Additional analysis of previously recorded, three-dimensional working trajectories of the bucket of large mine shovels was completed. The motion patterns, when transformed into a family of curves, serve as the basis for software-controlled machine kinematics transformation in the new human-robot control system.

A Modular Approach to Redundant Robot Control

International Nuclear Information System (INIS)

Anderson, R.J.

1997-12-01

This paper describes a modular approach for computing redundant robot kinematics. First some conventional redundant control methods are presented and shown to be 'passive control laws', i.e. they can be represented by a network consisting of passive elements. These networks are then put into modular form by applying scattering operator techniques. Additional subnetwork modules can then be added to further shape the motion. Modules for obstacle detection, joint limit avoidance, proximity sensing, and for imposing nonlinear velocity constraints are presented. The resulting redundant robot control system is modular, flexible and robust

Lattice Automata for Control of Self-Reconfigurable Robots

DEFF Research Database (Denmark)

Støy, Kasper

2015-01-01

are extreme versatility and robustness. The organisation of self-reconfigurable robots in a lattice structure and the emphasis on local communication between modules mean that lattice automata are a useful basis for control of self-reconfigurable robots. However, there are significant differences which arise...... mainly from the physical nature of self-reconfigurable robots as opposed to the virtual nature of lattice automata. The problems resulting from these differences are mutual exclusion, handling motion constraints of modules, and unrealistic assumption about global, spatial orientation. Despite...... these problems the self-reconfigurable robot community has successfully applied lattice automata to simple control problems. However, for more complex problems hybrid solutions based on lattice automata and distributed algorithms are used. Hence, lattice automata have shown to have potential for the control...

Study on robot motion control for intelligent welding processes based on the laser tracking sensor

Science.gov (United States)

Zhang, Bin; Wang, Qian; Tang, Chen; Wang, Ju

2017-06-01

A robot motion control method is presented for intelligent welding processes of complex spatial free-form curve seams based on the laser tracking sensor. First, calculate the tip position of the welding torch according to the velocity of the torch and the seam trajectory detected by the sensor. Then, search the optimal pose of the torch under constraints using genetic algorithms. As a result, the intersection point of the weld seam and the laser plane of the sensor is within the detectable range of the sensor. Meanwhile, the angle between the axis of the welding torch and the tangent of the weld seam meets the requirements. The feasibility of the control method is proved by simulation.

Multilateral Telecoordinated Control of Multiple Robots With Uncertain Kinematics.

Science.gov (United States)

Zhai, Di-Hua; Xia, Yuanqing

2017-06-06

This paper addresses the telecoordinated control of multiple robots in the simultaneous presence of asymmetric time-varying delays, nonpassive external forces, and uncertain kinematics/dynamics. To achieve the control objective, a neuroadaptive controller with utilizing prescribed performance control and switching control technique is developed, where the basic idea is to employ the concept of motion synchronization in each pair of master-slave robots and among all slave robots. By using the multiple Lyapunov-Krasovskii functionals method, the state-independent input-to-output practical stability of the closed-loop system is established. Compared with the previous approaches, the new design is straightforward and easier to implement and is applicable to a wider area. Simulation results on three pairs of three degrees-of-freedom robots confirm the theoretical findings.

Combination of Robot Simulation with Real-time Monitoring and Control

Directory of Open Access Journals (Sweden)

Jianyu YANG

2014-08-01

Full Text Available The paper mainly focuses in combining virtual reality based operation simulation with remote real-time monitoring and control method for an experimental robot. A system composition framework was designed and relative arm-wheel experimental robot platform was also built. Virtual robots and two virtual environments were developed. To locate the virtual robot within numerical environments, relative mathematical methods is also discussed, including analytic locating methods for linear motion and self-rotation, as well as linear transformation method with homogeneous matrices for turning motion, in order to decrease division calculations. Several experiments were carried out, trajectory errors were found because of relative slides between the wheel and the floor, during the locating experiments. Writing-monitoring experiments were also performed by programming the robotic arm to write a Chinese character, and the virtual robot in monitoring terminal perfectly followed all the movements. All the experiment results confirmed that virtual environment can not only be used as a good supplement to the traditional video monitoring method, but also offer better control experience during the operation.

Kinematics and Dynamics of Motion Control Based on Acceleration Control

Science.gov (United States)

Ohishi, Kiyoshi; Ohba, Yuzuru; Katsura, Seiichiro

The first IEEE International Workshop on Advanced Motion Control was held in 1990 pointed out the importance of physical interpretation of motion control. The software servoing technology is now common in machine tools, robotics, and mechatronics. It has been intensively developed for the numerical control (NC) machines. Recently, motion control in unknown environment will be more and more important. Conventional motion control is not always suitable due to the lack of adaptive capability to the environment. A more sophisticated ability in motion control is necessary for compliant contact with environment. Acceleration control is the key technology of motion control in unknown environment. The acceleration control can make a motion system to be a zero control stiffness system without losing the robustness. Furthermore, a realization of multi-degree-of-freedom motion is necessary for future human assistance. A human assistant motion will require various control stiffness corresponding to the task. The review paper focuses on the modal coordinate system to integrate the various control stiffness in the virtual axes. A bilateral teleoperation is a good candidate to consider the future human assistant motion and integration of decentralized systems. Thus the paper reviews and discusses the bilateral teleoperation from the control stiffness and the modal control design points of view.

Walking Pattern Generation of Dual-Arm Mobile Robot Using Preview Controller

OpenAIRE

P. Wu; W. Wu

2012-01-01

Based on the stability request of robot’s moving on the ground, the motion planning of dual-arm mobile robot when moving on the ground is studied and the preview control system is applied in the robot walking pattern generation. Direct question of robot kinematics in the extended task space is analyzed according to Degrees of Freedom configuration of the dual-arm mobile robot. It is proved that the preview control system could be used in the generation of robot Center of Mass forward trajecto...

Dynamic Modelling of a CPG-Controlled Amphibious Biomimetic Swimming Robot

Directory of Open Access Journals (Sweden)

Rui Ding

2013-04-01

Full Text Available This paper focuses on the modelling and control problems of a self-propelled, multimodal amphibious robot. Inspired by the undulatory body motions of fish and dolphins, the amphibious robot propels itself underwater by oscillations of several modular fish-like propelling units coupled with a pair of pectoral fins capable of non-continuous 360 degree rotation. In order to mimic fish-like undulating propulsion, a control architecture based on Central Pattern Generator (CPG is applied to the amphibious robot for robust swimming gaits, including forward and backward swimming and turning, etc. With the simplification of the robot as a multi-link serial mechanism, a Lagrangian function is employed to establish the hydrodynamic model for steady swimming. The CPG motion control law is then imported into the Lagrangian-based dynamic model, where an associated system of kinematics and dynamics is formed to solve real-time movements and, further, to guide the exploration of the CPG parameters and steady locomotion gaits. Finally, comparative results between the simulations and experiments are provided to show the effectiveness of the built control models.

Quasi-dynamic walk of a quadruped locomotion robot using optimal tracking control

International Nuclear Information System (INIS)

Uchida, Hiroaki; Nonami, Kenzo; Chiba, Yasunori; Koyama, Kakutaro.

1994-01-01

Recently, many research works of quadruped locomotion robots, which are considered to be operable on irregular terrain, have been carried out. In the case of realizing ideal motion control of the quadruped locomotion robot, it is assumed that hierarchical cooperative control consisting of decentralized control and centralized control is desirable. In the case that the locomotion robot moves at high speed, it is impossible to follow the desired trajectory because using only the feedback control method includes time delay. It is known that feedforward control input is valid for such motion control. In this paper, decentralized control is realized to apply optimal tracking control using feedforward control input to the quadruped locomotion robot, as the first step. As a result, it is determined that the angle variation of the foot and the stride applying optimal tracking control input are large compared with using only feedback control. It is verified that feedforward control input is useful to control the trajectory of the tip of the foot in high speed locomotion. (author)

Detecting Biological Motion for Human–Robot Interaction: A Link between Perception and Action

Directory of Open Access Journals (Sweden)

Alessia Vignolo

2017-06-01

Full Text Available One of the fundamental skills supporting safe and comfortable interaction between humans is their capability to understand intuitively each other’s actions and intentions. At the basis of this ability is a special-purpose visual processing that human brain has developed to comprehend human motion. Among the first “building blocks” enabling the bootstrapping of such visual processing is the ability to detect movements performed by biological agents in the scene, a skill mastered by human babies in the first days of their life. In this paper, we present a computational model based on the assumption that such visual ability must be based on local low-level visual motion features, which are independent of shape, such as the configuration of the body and perspective. Moreover, we implement it on the humanoid robot iCub, embedding it into a software architecture that leverages the regularities of biological motion also to control robot attention and oculomotor behaviors. In essence, we put forth a model in which the regularities of biological motion link perception and action enabling a robotic agent to follow a human-inspired sensory-motor behavior. We posit that this choice facilitates mutual understanding and goal prediction during collaboration, increasing the pleasantness and safety of the interaction.

Robust Control Design of Wheeled Inverted Pendulum Assistant Robot

Institute of Scientific and Technical Information of China (English)

Magdi S.Mahmoud; Mohammad T.Nasir

2017-01-01

This paper examines the design concept and mobile control strategy of the human assistant robot I-PENTAR（inverted pendulum type assistant robot）. The motion equation is derived considering the non-holonomic constraint of the twowheeled mobile robot. Different optimal control approaches are applied to a linearized model of I-PENTAR. These include linear quadratic regulator（LQR）, linear quadratic Gaussian control（LQG）, H2 control and H∞ control. Simulation is performed for all the approaches yielding good performance results.

Learning-based identification and iterative learning control of direct-drive robots

NARCIS (Netherlands)

Bukkems, B.H.M.; Kostic, D.; Jager, de A.G.; Steinbuch, M.

2005-01-01

A combination of model-based and Iterative Learning Control is proposed as a method to achieve high-quality motion control of direct-drive robots in repetitive motion tasks. We include both model-based and learning components in the total control law, as their individual properties influence the

Dynamic control of biped locomotion robot using optimal regulator

International Nuclear Information System (INIS)

Sano, Akihito; Furusho, Junji

1988-01-01

For moving in indoor space, it is generally recognized that biped locomotion is suitable. This paper proposes a hierarchical control strategy for the lower level where the position control or the force control at each joint is implemented. In the upper level control, the robot motion is divided into a sagittal plane and a lateral plane. We applied the optimal control algorithm to the motion control in the lateral plane in order to improve the robustness of the control system. The effects of these control schemes are shown by the experiments using the new walking robot BLR-G 1 and the parallel calculation system. BLR-G 1 has 9 degrees of freedom and equips the foot-pressure-sensors and a rate gyroscope. Complete dynamic walking is realized, in which the cycle for each step is about 1.0 second. (author)

Nonlinear control methods for planar carangiform robot fish locomotion

OpenAIRE

Morgansen, Kristi A.; Duindam, Vincent; Mason, Richard J.; Burdick, Joel W.; Murray, Richard M.

2001-01-01

Considers the design of motion control algorithms for robot fish. We present modeling, control design, and experimental trajectory tracking results for an experimental planar robotic fish system that is propelled using carangiform-like locomotion. Our model for the fish's propulsion is based on quasi-steady fluid flow. Using this model, we propose gaits for forward and turning trajectories and analyze system response under such control strategies. Our models and predictions are verified by ex...

Graphical programming: On-line robot simulation for telerobotic control

International Nuclear Information System (INIS)

McDonald, M.J.; Palmquist, R.D.

1993-01-01

Sandia has developed an advanced operational control system approach, caged Graphical Programming, to design and operate robotic waste cleanup and other hazardous duty robotic systems. The Graphical Programming approach produces robot systems that are faster to develop and use, safer in operation, and cheaper overall than altemative teleoperation or autonomous robot control systems. The Graphical Programming approach uses 3-D visualization and simulation software with intuitive operator interfaces for the programming and control of complex robotic systems. Graphical Programming Supervisor software modules allow an operator to command and simulate complex tasks in a graphic preview mode and, when acceptable, command the actual robots and monitor their motions with the graphic system. Graphical Progranuning Supervisors maintain registration with the real world and allow the robot to perform tasks that cannot be accurately represented with models alone by using a combination of model and sensor-based control. This paper describes the Graphical Programming approach, several example control systems that use Graphical Programming, and key features necessary for implementing successful Graphical Programming systems

Development of 6-DOF painting robot control system

Science.gov (United States)

Huang, Junbiao; Liu, Jianqun; Gao, Weiqiang

2017-01-01

With the development of society, the spraying technology of manufacturing industry in China has changed from the manual operation to the 6-DOF (Degree Of Freedom)robot automatic spraying. Spraying painting robot can not only complete the work which does harm to human being, but also improve the production efficiency and save labor costs. Control system is the most critical part of the 6-DOF robots, however, there is still a lack of relevant technology research in China. It is very necessary to study a kind of control system of 6-DOF spraying painting robots which is easy to operation, and has high efficiency and stable performance. With Googol controller platform, this paper develops programs based on Windows CE embedded systems to control the robot to finish the painting work. Software development is the core of the robot control system, including the direct teaching module, playback module, motion control module, setting module, man-machine interface, alarm module, log module, etc. All the development work of the entire software system has been completed, and it has been verified that the entire software works steady and efficient.

DEVELOPMENT OF TRAJECTORY CONTROL SYSTEM FOR THE OMNIDIRECTIONAL MOBILE ROBOT

Directory of Open Access Journals (Sweden)

Y. A. Kapitanyuk

2014-03-01

Full Text Available The article deals with a trajectory control system development for the omnidirectional mobile robot. This kind of robots gives the possibility to control separately each degree of freedom due to special design of the wheels, which greatly facilitates the solution of the spatial control tasks and makes it possible to focus directly on the development of algorithms. Control law synthesis is based on kinematic model of a solid body on a plane. Desired trajectory is defined as a smooth implicit function in a fixed coordinate system. Procedure of control design is represented by using a differential-geometric method of nonlinear transformation of the original model to the task-oriented form, which describes the longitudinal motion along a trajectory and orthogonal deviation. Proportional controllers with direct compensation of nonlinear terms are synthesized for the transformed model. Main results are represented by nonlinear control algorithms and experimental data. Practical implementation of considered control laws for the Robotino mobile robot by Festo Didactics Company is done for illustration of this approach workability. The cases of straight line motion and movement along a circle are represented as desirable trajectories, and the majority of practical tasks for mobile robots control can be implemented by their combination.

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...

Drive Control System for Pipeline Crawl Robot Based on CAN Bus

International Nuclear Information System (INIS)

Chen, H J; Gao, B T; Zhang, X H; Deng, Z Q

2006-01-01

Drive control system plays important roles in pipeline robot. In order to inspect the flaw and corrosion of seabed crude oil pipeline, an original mobile pipeline robot with crawler drive unit, power and monitor unit, central control unit, and ultrasonic wave inspection device is developed. The CAN bus connects these different function units and presents a reliable information channel. Considering the limited space, a compact hardware system is designed based on an ARM processor with two CAN controllers. With made-to-order CAN protocol for the crawl robot, an intelligent drive control system is developed. The implementation of the crawl robot demonstrates that the presented drive control scheme can meet the motion control requirements of the underwater pipeline crawl robot

Drive Control System for Pipeline Crawl Robot Based on CAN Bus

Energy Technology Data Exchange (ETDEWEB)

Chen, H J [Department of Electrical Engineering, Harbin Institute of Technology Harbin, Heilongjiang, 150001 (China); Gao, B T [Department of Electrical Engineering, Harbin Institute of Technology Harbin, Heilongjiang, 150001 (China); Zhang, X H [Department of Electrical Engineering, Harbin Institute of Technology Harbin, Heilongjiang, 150001 (China); Deng, Z Q [School of Mechanical Engineering, Harbin Institute of Technology Harbin, Heilongjiang, 150001 (China)

2006-10-15

Drive control system plays important roles in pipeline robot. In order to inspect the flaw and corrosion of seabed crude oil pipeline, an original mobile pipeline robot with crawler drive unit, power and monitor unit, central control unit, and ultrasonic wave inspection device is developed. The CAN bus connects these different function units and presents a reliable information channel. Considering the limited space, a compact hardware system is designed based on an ARM processor with two CAN controllers. With made-to-order CAN protocol for the crawl robot, an intelligent drive control system is developed. The implementation of the crawl robot demonstrates that the presented drive control scheme can meet the motion control requirements of the underwater pipeline crawl robot.

Neuromechanical Control for Hexapedal Robot Walking on Challenging Surfaces and Surface Classification

DEFF Research Database (Denmark)

Xiong, Xiaofeng; Wörgötter, Florentin; Manoonpong, Poramate

2014-01-01

The neuromechanical control principles of animal locomotion provide good insights for the development of bio-inspired legged robots for walking on challenging surfaces. Based on such principles, we developed a neuromechanical controller consisting of a modular neural network (MNN) and of virtual...... agonist–antagonist muscle mechanisms (VAAMs). The controller allows for variable compliant leg motions of a hexapod robot, thereby leading to energy-efficient walking on different surfaces. Without any passive mechanisms or torque and position feedback at each joint, the variable compliant leg motions...... are achieved by only changing the stiffness parameters of the VAAMs. In addition, six surfaces can be also classified by observing the motor signals generated by the controller. The performance of the controller is tested on a physical hexapod robot. Experimental results show that it can effectively walk...

Feasibility of interactive gesture control of a robotic microscope

Directory of Open Access Journals (Sweden)

Antoni Sven-Thomas

2015-09-01

Full Text Available Robotic devices become increasingly available in the clinics. One example are motorized surgical microscopes. While there are different scenarios on how to use the devices for autonomous tasks, simple and reliable interaction with the device is a key for acceptance by surgeons. We study, how gesture tracking can be integrated within the setup of a robotic microscope. In our setup, a Leap Motion Controller is used to track hand motion and adjust the field of view accordingly. We demonstrate with a survey that moving the field of view over a specified course is possible even for untrained subjects. Our results indicate that touch-less interaction with robots carrying small, near field gesture sensors is feasible and can be of use in clinical scenarios, where robotic devices are used in direct proximity of patient and physicians.

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.

Extending an Industrial Robot Controller-Implementation and Applications of a Fast Open Sensor Interface

OpenAIRE

Blomdell, Anders; Bolmsjö, Gunnar; Brogårdh, Torgny; Cederberg, Per; Isaksson, Mats; Johansson, Rolf; Haage, Mathias; Nilsson, Klas; Olsson, Magnus; Olsson, Tomas; Robertsson, Anders; Wang, Jianjun

2005-01-01

Many promising robotics research results were obtained during the late 1970s and early 1980s. Some examples include Cartesian force control and advanced motion planning. Now, 20 years and many research projects later, many technologies still have not reached industrial usage. An important question to consider is how this situation can be improved for future deployment of necessary technologies. Today, modern robot control systems used in industry provide highly optimized motion control that w...

Myoelectric Control Techniques for a Rehabilitation Robot

Directory of Open Access Journals (Sweden)

Alan Smith

2011-01-01

Full Text Available This work examines two different types of myoelectric control schemes for the purpose of rehabilitation robot applications. The first is a commonly used technique based on a Gaussian classifier. It is implemented in real time for healthy subjects in addition to a subject with Central Cord Syndrome (CCS. The myoelectric control scheme is used to control three degrees of freedom (DOF on a robot manipulator which corresponded to the robot's elbow joint, wrist joint, and gripper. The classes of motion controlled include elbow flexion and extension, wrist pronation and supination, hand grasping and releasing, and rest. Healthy subjects were able to achieve 90% accuracy. Single DOF controllers were first tested on the subject with CCS and he achieved 100%, 96%, and 85% accuracy for the elbow, gripper, and wrist controllers respectively. Secondly, he was able to control the three DOF controller at 68% accuracy. The potential applications for this scheme are rehabilitation and teleoperation. To overcome limitations in the pattern recognition based scheme, a second myoelectric control scheme is also presented which is trained using electromyographic (EMG data derived from natural reaching motions in the sagittal plane. This second scheme is based on a time delayed neural network (TDNN which has the ability to control multiple DOF at once. The controller tracked a subject's elbow and shoulder joints in the sagittal plane. Results showed an average error of 19° for the two joints. This myoelectric control scheme has the potential of being used in the development of exoskeleton and orthotic rehabilitation applications.

Radial polar histogram: obstacle avoidance and path planning for robotic cognition and motion control

Science.gov (United States)

Wang, Po-Jen; Keyawa, Nicholas R.; Euler, Craig

2012-01-01

In order to achieve highly accurate motion control and path planning for a mobile robot, an obstacle avoidance algorithm that provided a desired instantaneous turning radius and velocity was generated. This type of obstacle avoidance algorithm, which has been implemented in California State University Northridge's Intelligent Ground Vehicle (IGV), is known as Radial Polar Histogram (RPH). The RPH algorithm utilizes raw data in the form of a polar histogram that is read from a Laser Range Finder (LRF) and a camera. A desired open block is determined from the raw data utilizing a navigational heading and an elliptical approximation. The left and right most radii are determined from the calculated edges of the open block and provide the range of possible radial paths the IGV can travel through. In addition, the calculated obstacle edge positions allow the IGV to recognize complex obstacle arrangements and to slow down accordingly. A radial path optimization function calculates the best radial path between the left and right most radii and is sent to motion control for speed determination. Overall, the RPH algorithm allows the IGV to autonomously travel at average speeds of 3mph while avoiding all obstacles, with a processing time of approximately 10ms.

Direct adaptive control of a PUMA 560 industrial robot

Science.gov (United States)

Seraji, Homayoun; Lee, Thomas; Delpech, Michel

1989-01-01

The implementation and experimental validation of a new direct adaptive control scheme on a PUMA 560 industrial robot is described. The testbed facility consists of a Unimation PUMA 560 six-jointed robot and controller, and a DEC MicroVAX II computer which hosts the Robot Control C Library software. The control algorithm is implemented on the MicroVAX which acts as a digital controller for the PUMA robot, and the Unimation controller is effectively bypassed and used merely as an I/O device to interface the MicroVAX to the joint motors. The control algorithm for each robot joint consists of an auxiliary signal generated by a constant-gain Proportional plus Integral plus Derivative (PID) controller, and an adaptive position-velocity (PD) feedback controller with adjustable gains. The adaptive independent joint controllers compensate for the inter-joint couplings and achieve accurate trajectory tracking without the need for the complex dynamic model and parameter values of the robot. Extensive experimental results on PUMA joint control are presented to confirm the feasibility of the proposed scheme, in spite of strong interactions between joint motions. Experimental results validate the capabilities of the proposed control scheme. The control scheme is extremely simple and computationally very fast for concurrent processing with high sampling rates.

Design and control of a pneumatic musculoskeletal biped robot.

Science.gov (United States)

Zang, Xizhe; Liu, Yixiang; Liu, Xinyu; Zhao, Jie

2016-04-29

Pneumatic artificial muscles are quite promising actuators for humanoid robots owing to their similar characteristics with human muscles. Moreover, biologically inspired musculoskeletal systems are particularly important for humanoid robots to perform versatile dynamic tasks. This study aims to develop a pneumatic musculoskeletal biped robot, and its controller, to realize human-like walking. According to the simplified musculoskeletal structure of human lower limbs, each leg of the biped robot is driven by nine muscles, including three pairs of monoarticular muscles which are arranged in the flexor-extensor form, as well as three biarticular muscles which span two joints. To lower cost, high-speed on/off solenoid valves rather than proportional valves are used to control the muscles. The joint trajectory tracking controller based on PID control method is designed to achieve the desired motion. Considering the complex characteristics of pneumatic artificial muscles, the control model is obtained through parameter identification experiments. Preliminary experimental results demonstrate that the biped robot is able to walk with this control strategy. The proposed musculoskeletal structure and control strategy are effective for the biped robot to achieve human-like walking.

Automated Kinematics Equations Generation and Constrained Motion Planning Resolution for Modular and Reconfigurable Robots

Energy Technology Data Exchange (ETDEWEB)

Pin, Francois G.; Love, Lonnie L.; Jung, David L.

2004-03-29

Contrary to the repetitive tasks performed by industrial robots, the tasks in most DOE missions such as environmental restoration or Decontamination and Decommissioning (D&D) can be characterized as ''batches-of-one'', in which robots must be capable of adapting to changes in constraints, tools, environment, criteria and configuration. No commercially available robot control code is suitable for use with such widely varying conditions. In this talk we present our development of a ''generic code'' to allow real time (at loop rate) robot behavior adaptation to changes in task objectives, tools, number and type of constraints, modes of controls or kinematics configuration. We present the analytical framework underlying our approach and detail the design of its two major modules for the automatic generation of the kinematics equations when the robot configuration or tools change and for the motion planning under time-varying constraints. Sample problems illustrating the capabilities of the developed system are presented.

3D force control for robotic-assisted beating heart surgery based on viscoelastic tissue model.

Science.gov (United States)

Liu, Chao; Moreira, Pedro; Zemiti, Nabil; Poignet, Philippe

2011-01-01

Current cardiac surgery faces the challenging problem of heart beating motion even with the help of mechanical stabilizer which makes delicate operation on the heart surface difficult. Motion compensation methods for robotic-assisted beating heart surgery have been proposed recently in literature, but research on force control for such kind of surgery has hardly been reported. Moreover, the viscoelasticity property of the interaction between organ tissue and robotic instrument further complicates the force control design which is much easier in other applications by assuming the interaction model to be elastic (industry, stiff object manipulation, etc.). In this work, we present a three-dimensional force control method for robotic-assisted beating heart surgery taking into consideration of the viscoelastic interaction property. Performance studies based on our D2M2 robot and 3D heart beating motion information obtained through Da Vinci™ system are provided.

Contribution to control of robotics structures and dynamic behaviour

International Nuclear Information System (INIS)

Gilliot, Jean-Marie

1990-01-01

The scope of this thesis is the simulation of the dynamics of complex rigid multi-body systems involved in robotics, in order to control them. In the first stage, methods for obtaining equations and models required for simulation and control purposes are proposed and discussed: - determination of constraint equations using the jacobian matrices, - elaboration of direct and inverse dynamics of manipulators. The second part of this thesis deals with the different concepts and components involved in the setting of simulation systems for Robotics Application Programs: models, emulators and the software development environment. The control algorithms are then introduced as a particular class of robotics application programs. A simulator has been developed, allowing the calculation and the visualisation of robot motions, driven by generalized torques. Some examples of control programs generating such control torques are then presented to illustrate the use of the simulator. (author) [fr

Integration of advanced teleoperation technologies for control of space robots

Science.gov (United States)

Stagnaro, Michael J.

1993-01-01

Teleoperated robots require one or more humans to control actuators, mechanisms, and other robot equipment given feedback from onboard sensors. To accomplish this task, the human or humans require some form of control station. Desirable features of such a control station include operation by a single human, comfort, and natural human interfaces (visual, audio, motion, tactile, etc.). These interfaces should work to maximize performance of the human/robot system by streamlining the link between human brain and robot equipment. This paper describes development of a control station testbed with the characteristics described above. Initially, this testbed will be used to control two teleoperated robots. Features of the robots include anthropomorphic mechanisms, slaving to the testbed, and delivery of sensory feedback to the testbed. The testbed will make use of technologies such as helmet mounted displays, voice recognition, and exoskeleton masters. It will allow tor integration and testing of emerging telepresence technologies along with techniques for coping with control link time delays. Systems developed from this testbed could be applied to ground control of space based robots. During man-tended operations, the Space Station Freedom may benefit from ground control of IVA or EVA robots with science or maintenance tasks. Planetary exploration may also find advanced teleoperation systems to be very useful.

Two-dimensional laser servoing for precision motion control of an ODV robotic license plate recognition system

Science.gov (United States)

Song, Zhen; Moore, Kevin L.; Chen, YangQuan; Bahl, Vikas

2003-09-01

As an outgrowth of series of projects focused on mobility of unmanned ground vehicles (UGV), an omni-directional (ODV), multi-robot, autonomous mobile parking security system has been developed. The system has two types of robots: the low-profile Omni-Directional Inspection System (ODIS), which can be used for under-vehicle inspections, and the mid-sized T4 robot, which serves as a ``marsupial mothership'' for the ODIS vehicles and performs coarse resolution inspection. A key task for the T4 robot is license plate recognition (LPR). For a successful LPR task without compromising the recognition rate, the robot must be able to identify the bumper locations of vehicles in the parking area and then precisely position the LPR camera relative to the bumper. This paper describes a 2D-laser scanner based approach to bumper identification and laser servoing for the T4 robot. The system uses a gimbal-mounted scanning laser. As the T4 robot travels down a row of parking stalls, data is collected from the laser every 100ms. For each parking stall in the range of the laser during the scan, the data is matched to a ``bumper box'' corresponding to where a car bumper is expected, resulting in a point cloud of data corresponding to a vehicle bumper for each stall. Next, recursive line-fitting algorithms are used to determine a line for the data in each stall's ``bumper box.'' The fitting technique uses Hough based transforms, which are robust against segmentation problems and fast enough for real-time line fitting. Once a bumper line is fitted with an acceptable confidence, the bumper location is passed to the T4 motion controller, which moves to position the LPR camera properly relative to the bumper. The paper includes examples and results that show the effectiveness of the technique, including its ability to work in real-time.

Heart Motion Prediction in Robotic-Assisted Beating Heart Surgery: A Nonlinear Fast Adaptive Approach

Directory of Open Access Journals (Sweden)

Fan Liang

2013-01-01

Full Text Available Off-pump Coronary Artery Bypass Graft (CABG surgery outperforms traditional on-pump surgery because the assisted robotic tools can alleviate the relative motion between the beating heart and robotic tools. Therefore, it is possible for the surgeon to operate on the beating heart and thus lessens post surgery complications for the patients. Due to the highly irregular and non-stationary nature of heart motion, it is critical that the beating heart motion is predicted in the model-based track control procedures. It is technically preferable to model heart motion in a nonlinear way because the characteristic analysis of 3D heart motion data through Bi-spectral analysis and Fourier methods demonstrates the involved nonlinearity of heart motion. We propose an adaptive nonlinear heart motion model based on the Volterra Series in this paper. We also design a fast lattice structure to achieve computational-efficiency for real-time online predictions. We argue that the quadratic term of the Volterra Series can improve the prediction accuracy by covering sharp change points and including the motion with sufficient detail. The experiment results indicate that the adaptive nonlinear heart motion prediction algorithm outperforms the autoregressive (AR and the time-varying Fourier-series models in terms of the root mean square of the prediction error and the prediction error in extreme cases.

Control of free-flying space robot manipulator systems

Science.gov (United States)

Cannon, Robert H., Jr.

1989-01-01

Control techniques for self-contained, autonomous free-flying space robots are being tested and developed. Free-flying space robots are envisioned as a key element of any successful long term presence in space. These robots must be capable of performing the assembly, maintenance, and inspection, and repair tasks that currently require astronaut extra-vehicular activity (EVA). Use of robots will provide economic savings as well as improved astronaut safety by reducing and in many cases, eliminating the need for human EVA. The focus of the work is to develop and carry out a set of research projects using laboratory models of satellite robots. These devices use air-cushion-vehicle (ACV) technology to simulate in two dimensions the drag-free, zero-g conditions of space. Current work is divided into six major projects or research areas. Fixed-base cooperative manipulation work represents our initial entry into multiple arm cooperation and high-level control with a sophisticated user interface. The floating-base cooperative manipulation project strives to transfer some of the technologies developed in the fixed-base work onto a floating base. The global control and navigation experiment seeks to demonstrate simultaneous control of the robot manipulators and the robot base position so that tasks can be accomplished while the base is undergoing a controlled motion. The multiple-vehicle cooperation project's goal is to demonstrate multiple free-floating robots working in teams to carry out tasks too difficult or complex for a single robot to perform. The Location Enhancement Arm Push-off (LEAP) activity's goal is to provide a viable alternative to expendable gas thrusters for vehicle propulsion wherein the robot uses its manipulators to throw itself from place to place. Because the successful execution of the LEAP technique requires an accurate model of the robot and payload mass properties, it was deemed an attractive testbed for adaptive control technology.

A sub-target approach to the kinodynamic motion control of a wheeled mobile robot

Science.gov (United States)

Motonaka, Kimiko; Watanabe, Keigo; Maeyama, Shoichi

2018-02-01

A mobile robot with two independently driven wheels is popular, but it is difficult to stabilize it by a continuous controller with a constant gain, due to its nonholonomic property. It is guaranteed that a nonholonomic controlled object can always be converged to an arbitrary point using a switching control method or a quasi-continuous control method based on an invariant manifold in a chained form. From this, the authors already proposed a kinodynamic controller to converge the states of such a two-wheeled mobile robot to the arbitrary target position while avoiding obstacles, by combining the control based on the invariant manifold and the harmonic potential field (HPF). On the other hand, it was confirmed in the previous research that there is a case that the robot cannot avoid the obstacle because there is no enough space to converge the current state to the target state. In this paper, we propose a method that divides the final target position into some sub-target positions and moves the robot step by step, and it is confirmed by the simulation that the robot can converge to the target position while avoiding obstacles using the proposed method.

Humanlike robot hands controlled by brain activity arouse illusion of ownership in operators

Science.gov (United States)

Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi

2013-08-01

Operators of a pair of robotic hands report ownership for those hands when they hold image of a grasp motion and watch the robot perform it. We present a novel body ownership illusion that is induced by merely watching and controlling robot's motions through a brain machine interface. In past studies, body ownership illusions were induced by correlation of such sensory inputs as vision, touch and proprioception. However, in the presented illusion none of the mentioned sensations are integrated except vision. Our results show that during BMI-operation of robotic hands, the interaction between motor commands and visual feedback of the intended motions is adequate to incorporate the non-body limbs into one's own body. Our discussion focuses on the role of proprioceptive information in the mechanism of agency-driven illusions. We believe that our findings will contribute to improvement of tele-presence systems in which operators incorporate BMI-operated robots into their body representations.

A Course in Simulation and Demonstration of Humanoid Robot Motion

Science.gov (United States)

Liu, Hsin-Yu; Wang, Wen-June; Wang, Rong-Jyue

2011-01-01

An introductory course for humanoid robot motion realization for undergraduate and graduate students is presented in this study. The basic operations of AX-12 motors and the mechanics combination of a 16 degrees-of-freedom (DOF) humanoid robot are presented first. The main concepts of multilink systems, zero moment point (ZMP), and feedback…

The Combined Effects of Adaptive Control and Virtual Reality on Robot-Assisted Fine Hand Motion Rehabilitation in Chronic Stroke Patients: A Case Study.

Science.gov (United States)

Huang, Xianwei; Naghdy, Fazel; Naghdy, Golshah; Du, Haiping; Todd, Catherine

2018-01-01

Robot-assisted therapy is regarded as an effective and reliable method for the delivery of highly repetitive training that is needed to trigger neuroplasticity following a stroke. However, the lack of fully adaptive assist-as-needed control of the robotic devices and an inadequate immersive virtual environment that can promote active participation during training are obstacles hindering the achievement of better training results with fewer training sessions required. This study thus focuses on these research gaps by combining these 2 key components into a rehabilitation system, with special attention on the rehabilitation of fine hand motion skills. The effectiveness of the proposed system is tested by conducting clinical trials on a chronic stroke patient and verified through clinical evaluation methods by measuring the key kinematic features such as active range of motion (ROM), finger strength, and velocity. By comparing the pretraining and post-training results, the study demonstrates that the proposed method can further enhance the effectiveness of fine hand motion rehabilitation training by improving finger ROM, strength, and coordination. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

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

Attitude dynamics and control of a spacecraft like a robotic manipulator when implementing on-orbit servicing

Science.gov (United States)

Da Fonseca, Ijar M.; Goes, Luiz C. S.; Seito, Narumi; da Silva Duarte, Mayara K.; de Oliveira, Élcio Jeronimo

2017-08-01

In space the manipulators working space is characterized by the microgravity environment. In this environment the spacecraft floats and its rotational/translational motion may be excited by any internal and external disturbances. The complete system, i.e., the spacecraft and the associated robotic manipulator, floats and is sensitive to any reaction force and torque related to the manipulator's operation. In this sense the effort done by the robot may result in torque about the system center of mass and also in forces changing its translational motion. This paper analyzes the impact of the robot manipulator dynamics on the attitude motion and the associated control effort to keep the attitude stable during the manipulator's operation. The dynamics analysis is performed in the close proximity phase of rendezvous docking/berthing operation. In such scenario the linear system equations for the translation and attitude relative motions are appropriate. The computer simulations are implemented for the relative translational and rotational motion. The equations of motion have been simulated through computer by using the MatLab software. The LQR and the PID control laws are used for linear and nonlinear control, respectively, aiming to keep the attitude stable while the robot is in and out of service. The gravity-gradient and the residual magnetic torque are considered as external disturbances. The control efforts are analyzed for the manipulator in and out of service. The control laws allow the system stabilization and good performance when the manipulator is in service.

Towards frameless maskless SRS through real-time 6DoF robotic motion compensation

Science.gov (United States)

Belcher, Andrew H.; Liu, Xinmin; Chmura, Steven; Yenice, Kamil; Wiersma, Rodney D.

2017-12-01

Stereotactic radiosurgery (SRS) uses precise dose placement to treat conditions of the CNS. Frame-based SRS uses a metal head ring fixed to the patient’s skull to provide high treatment accuracy, but patient comfort and clinical workflow may suffer. Frameless SRS, while potentially more convenient, may increase uncertainty of treatment accuracy and be physiologically confining to some patients. By incorporating highly precise robotics and advanced software algorithms into frameless treatments, we present a novel frameless and maskless SRS system where a robot provides real-time 6DoF head motion stabilization allowing positional accuracies to match or exceed those of traditional frame-based SRS. A 6DoF parallel kinematics robot was developed and integrated with a real-time infrared camera in a closed loop configuration. A novel compensation algorithm was developed based on an iterative closest-path correction approach. The robotic SRS system was tested on six volunteers, whose motion was monitored and compensated for in real-time over 15 min simulated treatments. The system’s effectiveness in maintaining the target’s 6DoF position within preset thresholds was determined by comparing volunteer head motion with and without compensation. Comparing corrected and uncorrected motion, the 6DoF robotic system showed an overall improvement factor of 21 in terms of maintaining target position within 0.5 mm and 0.5 degree thresholds. Although the system’s effectiveness varied among the volunteers examined, for all volunteers tested the target position remained within the preset tolerances 99.0% of the time when robotic stabilization was used, compared to 4.7% without robotic stabilization. The pre-clinical robotic SRS compensation system was found to be effective at responding to sub-millimeter and sub-degree cranial motions for all volunteers examined. The system’s success with volunteers has demonstrated its capability for implementation with frameless and

Towards frameless maskless SRS through real-time 6DoF robotic motion compensation.

Science.gov (United States)

Belcher, Andrew H; Liu, Xinmin; Chmura, Steven; Yenice, Kamil; Wiersma, Rodney D

2017-11-13

Stereotactic radiosurgery (SRS) uses precise dose placement to treat conditions of the CNS. Frame-based SRS uses a metal head ring fixed to the patient's skull to provide high treatment accuracy, but patient comfort and clinical workflow may suffer. Frameless SRS, while potentially more convenient, may increase uncertainty of treatment accuracy and be physiologically confining to some patients. By incorporating highly precise robotics and advanced software algorithms into frameless treatments, we present a novel frameless and maskless SRS system where a robot provides real-time 6DoF head motion stabilization allowing positional accuracies to match or exceed those of traditional frame-based SRS. A 6DoF parallel kinematics robot was developed and integrated with a real-time infrared camera in a closed loop configuration. A novel compensation algorithm was developed based on an iterative closest-path correction approach. The robotic SRS system was tested on six volunteers, whose motion was monitored and compensated for in real-time over 15 min simulated treatments. The system's effectiveness in maintaining the target's 6DoF position within preset thresholds was determined by comparing volunteer head motion with and without compensation. Comparing corrected and uncorrected motion, the 6DoF robotic system showed an overall improvement factor of 21 in terms of maintaining target position within 0.5 mm and 0.5 degree thresholds. Although the system's effectiveness varied among the volunteers examined, for all volunteers tested the target position remained within the preset tolerances 99.0% of the time when robotic stabilization was used, compared to 4.7% without robotic stabilization. The pre-clinical robotic SRS compensation system was found to be effective at responding to sub-millimeter and sub-degree cranial motions for all volunteers examined. The system's success with volunteers has demonstrated its capability for implementation with frameless and maskless SRS

Robotic guarded motion system and method

Science.gov (United States)

Bruemmer, David J.

2010-02-23

A robot platform includes perceptors, locomotors, and a system controller. The system controller executes instructions for repeating, on each iteration through an event timing loop, the acts of defining an event horizon, detecting a range to obstacles around the robot, and testing for an event horizon intrusion. Defining the event horizon includes determining a distance from the robot that is proportional to a current velocity of the robot and testing for the event horizon intrusion includes determining if any range to the obstacles is within the event horizon. Finally, on each iteration through the event timing loop, the method includes reducing the current velocity of the robot in proportion to a loop period of the event timing loop if the event horizon intrusion occurs.

Robust coordinated control of a dual-arm space robot

Science.gov (United States)

Shi, Lingling; Kayastha, Sharmila; Katupitiya, Jay

2017-09-01

Dual-arm space robots are more capable of implementing complex space tasks compared with single arm space robots. However, the dynamic coupling between the arms and the base will have a serious impact on the spacecraft attitude and the hand motion of each arm. Instead of considering one arm as the mission arm and the other as the balance arm, in this work two arms of the space robot perform as mission arms aimed at accomplishing secure capture of a floating target. The paper investigates coordinated control of the base's attitude and the arms' motion in the task space in the presence of system uncertainties. Two types of controllers, i.e. a Sliding Mode Controller (SMC) and a nonlinear Model Predictive Controller (MPC) are verified and compared with a conventional Computed-Torque Controller (CTC) through numerical simulations in terms of control accuracy and system robustness. Both controllers eliminate the need to linearly parameterize the dynamic equations. The MPC has been shown to achieve performance with higher accuracy than CTC and SMC in the absence of system uncertainties under the condition that they consume comparable energy. When the system uncertainties are included, SMC and CTC present advantageous robustness than MPC. Specifically, in a case where system inertia increases, SMC delivers higher accuracy than CTC and costs the least amount of energy.

Design, Implementation and Validation of the Three-Wheel Holonomic Motion System of the Assistant Personal Robot (APR

Directory of Open Access Journals (Sweden)

Javier Moreno

2016-10-01

Full Text Available This paper presents the design, implementation and validation of the three-wheel holonomic motion system of a mobile robot designed to operate in homes. The holonomic motion system is described in terms of mechanical design and electronic control. The paper analyzes the kinematics of the motion system and validates the estimation of the trajectory comparing the displacement estimated with the internal odometry of the motors and the displacement estimated with a SLAM procedure based on LIDAR information. Results obtained in different experiments have shown a difference on less than 30 mm between the position estimated with the SLAM and odometry, and a difference in the angular orientation of the mobile robot lower than 5° in absolute displacements up to 1000 mm.

Design, Implementation and Validation of the Three-Wheel Holonomic Motion System of the Assistant Personal Robot (APR).

Science.gov (United States)

Moreno, Javier; Clotet, Eduard; Lupiañez, Ruben; Tresanchez, Marcel; Martínez, Dani; Pallejà, Tomàs; Casanovas, Jordi; Palacín, Jordi

2016-10-10

This paper presents the design, implementation and validation of the three-wheel holonomic motion system of a mobile robot designed to operate in homes. The holonomic motion system is described in terms of mechanical design and electronic control. The paper analyzes the kinematics of the motion system and validates the estimation of the trajectory comparing the displacement estimated with the internal odometry of the motors and the displacement estimated with a SLAM procedure based on LIDAR information. Results obtained in different experiments have shown a difference on less than 30 mm between the position estimated with the SLAM and odometry, and a difference in the angular orientation of the mobile robot lower than 5° in absolute displacements up to 1000 mm.

Design, Implementation and Validation of the Three-Wheel Holonomic Motion System of the Assistant Personal Robot (APR)

Science.gov (United States)

Moreno, Javier; Clotet, Eduard; Lupiañez, Ruben; Tresanchez, Marcel; Martínez, Dani; Pallejà, Tomàs; Casanovas, Jordi; Palacín, Jordi

2016-01-01

This paper presents the design, implementation and validation of the three-wheel holonomic motion system of a mobile robot designed to operate in homes. The holonomic motion system is described in terms of mechanical design and electronic control. The paper analyzes the kinematics of the motion system and validates the estimation of the trajectory comparing the displacement estimated with the internal odometry of the motors and the displacement estimated with a SLAM procedure based on LIDAR information. Results obtained in different experiments have shown a difference on less than 30 mm between the position estimated with the SLAM and odometry, and a difference in the angular orientation of the mobile robot lower than 5° in absolute displacements up to 1000 mm. PMID:27735857

Biological inspiration used for robots motion synthesis.

Science.gov (United States)

Zielińska, Teresa

2009-01-01

This work presents a biologically inspired method of gait generation. Bipedal gait pattern (for hip and knee joints) was taken into account giving the reference trajectories in a learning task. The four coupled oscillators were taught to generate the outputs similar to those in a human gait. After applying the correction functions the obtained generation method was validated using ZMP criterion. The formula suitable for real-time motion generation taking into account the positioning errors was also formulated. The small real robot prototype was tested to be able walk successfully following the elaborated motion pattern.

Effect of robotic-assisted three-dimensional repetitive motion to improve hand motor function and control in children with handwriting deficits: a nonrandomized phase 2 device trial.

Science.gov (United States)

Palsbo, Susan E; Hood-Szivek, Pamela

2012-01-01

We explored the efficacy of robotic technology in improving handwriting in children with impaired motor skills. Eighteen participants had impairments arising from cerebral palsy (CP), autism spectrum disorder (ASD), attention deficit disorder (ADD), attention deficit hyperactivity disorder (ADHD), or other disorders. The intervention was robotic-guided three-dimensional repetitive motion in 15-20 daily sessions of 25-30 min each over 4-8 wk. Fine motor control improved for the children with learning disabilities and those ages 9 or older but not for those with CP or under age 9. All children with ASD or ADHD referred for slow writing speed were able to increase speed while maintaining legibility. Three-dimensional, robot-assisted, repetitive motion training improved handwriting fluidity in children with mild to moderate fine motor deficits associated with ASD or ADHD within 10 hr of training. This dosage may not be sufficient for children with CP. Copyright © 2012 by the American Occupational Therapy Association, Inc.

SIMULATION OF ADAPTIVE BEHAVIOR IN THE CONTEXT OF SOLVING AN AUTONOMOUS ROBOTIC VEHICLE MOTION TASK ON TWO-DIMENSIONAL PLANE WITH OBSTACLES

Directory of Open Access Journals (Sweden)

R. A. Prakapovich

2014-01-01

Full Text Available An adaptive neurocontroller for autonomous robotic vehicle control, which is designed to generate control signals (according to preprogrammed motion algorithm and to develop individual reactions to some external impacts during functioning process, that allows the robot to adapt to external environment changes, is suggested. To debug and test the proposed neurocontroller a specially designed program, able to simulate the sensory and executive systems operation of the robotic vehicle, is used.

PID motion control tuning rules in a damping injection framework

NARCIS (Netherlands)

Tadele, T.S.; de Vries, Theodorus J.A.; Stramigioli, Stefano

2013-01-01

This paper presents a general design approach for a performance based tuning of a damping injection framework impedance controller by using insights from PID motion control tuning rules. The damping injection framework impedance controller is suitable for human friendly robots as it enhances safety

Manipulator motion planning for high-speed robotic laser cutting

OpenAIRE

Dolgui , Alexandre; Pashkevich , Anatol

2009-01-01

Abstract Recent advances in laser technology, and especially the essential increase of the cutting speed, motivate amending the existing robot path methods, which do not allow the complete utilisation of the actuator capabilities as well as neglect some particularities in the mechanical design of the wrist of the manipulator arm. This research addresses the optimisation of the 6-axes robot motions for continuous contour tracking while considering the redundancy caused by the tool a...

Motion Detection from Mobile Robots with Fuzzy Threshold Selection in Consecutive 2D Laser Scans

Directory of Open Access Journals (Sweden)

María A. Martínez

2015-01-01

Full Text Available Motion detection and tracking is a relevant problem for mobile robots during navigation to avoid collisions in dynamic environments or in applications where service robots interact with humans. This paper presents a simple method to distinguish mobile obstacles from the environment that is based on applying fuzzy threshold selection to consecutive two-dimensional (2D laser scans previously matched with robot odometry. The proposed method has been tested with the Auriga-α mobile robot in indoors to estimate the motion of nearby pedestrians.

Multi-agent System for Off-line Coordinated Motion Planning of Multiple Industrial Robots

Directory of Open Access Journals (Sweden)

Shital S. Chiddarwar

2011-03-01

Full Text Available This article presents an agent based framework for coordinated motion planning of multiple robots. The emerging paradigm of agent based systems is implemented to address various issues related to safe and fast task execution when multiple robots share a common workspace. In the proposed agent based framework, each issue vital for coordinated motion planning of multiple robots and every robot participating in coordinated task is considered as an agent. The identified agents are interfaced with each other in order to incorporate the desired flexibility in the developed framework. This framework gives a complete strategy for determination of optimal trajectories of robots working in coordination with due consideration to their kinematic, dynamic and payload constraint. The complete architecture of the proposed framework and the detailed discussion on various modules are covered in this paper.

Motion control of the Twente humanoid head

NARCIS (Netherlands)

Visser, L.C.; Carloni, Raffaella; Stramigioli, Stefano

2009-01-01

In this work, we present the design and the realization of the motion control algorithm implemented in the Twente hu- manoid head, a seven degrees of freedom (dof) robotic sys- tem. The aim of the project is to have a humanoid head that can serve as a research platform for human-machine interac-

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.

Control of compliant anthropomimetic robot joint

Directory of Open Access Journals (Sweden)

Svetozarević Bratislav

2011-01-01

Full Text Available In this paper we propose a control strategy for a robot joint which fully mimics the typical human joint structure. The joint drive is based on two actuators (dc motors, agonist and antagonist, acting through compliant tendons and forming a nonlinear multi-input multi-output (MIMO system. At any time, we consider one actuator, the puller, as being responsible for motion control, while the role of the other is to keep its tendon force at some appropriate low level. This human-like and energetically efficient approach requires the control of 'switching', or exchanging roles between actuators. Moreover, an algorithm based on adaptive force reference is used to solve a problem of slacken tendons during the switching and to increase the energy efficiency. This approach was developed and evaluated on increasingly complex robot joint configurations, starting with simple and noncompliant system, and finishing with nonlinear and compliant system.

Sensory Integration with Articulated Motion on a Humanoid Robot

Directory of Open Access Journals (Sweden)

J. Rojas

2005-01-01

Full Text Available This paper describes the integration of articulated motion with auditory and visual sensory information that enables a humanoid robot to achieve certain reflex actions that mimic those of people. Reflexes such as reach-and-grasp behavior enables the robot to learn, through experience, its own state and that of the world. A humanoid robot with binaural audio input, stereo vision, and pneumatic arms and hands exhibited tightly coupled sensory-motor behaviors in four different demonstrations. The complexity of successive demonstrations was increased to show that the reflexive sensory-motor behaviors combine to perform increasingly complex tasks. The humanoid robot executed these tasks effectively and established the groundwork for the further development of hardware and software systems, sensory-motor vector-space representations, and coupling with higher-level cognition.

Advanced robot locomotion.

Energy Technology Data Exchange (ETDEWEB)

Neely, Jason C.; Sturgis, Beverly Rainwater; Byrne, Raymond Harry; Feddema, John Todd; Spletzer, Barry Louis; Rose, Scott E.; Novick, David Keith; Wilson, David Gerald; Buerger, Stephen P.

2007-01-01

This report contains the results of a research effort on advanced robot locomotion. The majority of this work focuses on walking robots. Walking robot applications include delivery of special payloads to unique locations that require human locomotion to exo-skeleton human assistance applications. A walking robot could step over obstacles and move through narrow openings that a wheeled or tracked vehicle could not overcome. It could pick up and manipulate objects in ways that a standard robot gripper could not. Most importantly, a walking robot would be able to rapidly perform these tasks through an intuitive user interface that mimics natural human motion. The largest obstacle arises in emulating stability and balance control naturally present in humans but needed for bipedal locomotion in a robot. A tracked robot is bulky and limited, but a wide wheel base assures passive stability. Human bipedal motion is so common that it is taken for granted, but bipedal motion requires active balance and stability control for which the analysis is non-trivial. This report contains an extensive literature study on the state-of-the-art of legged robotics, and it additionally provides the analysis, simulation, and hardware verification of two variants of a proto-type leg design.

Initial Experiments with the Leap Motion as a User Interface in Robotic Endonasal Surgery.

Science.gov (United States)

Travaglini, T A; Swaney, P J; Weaver, Kyle D; Webster, R J

The Leap Motion controller is a low-cost, optically-based hand tracking system that has recently been introduced on the consumer market. Prior studies have investigated its precision and accuracy, toward evaluating its usefulness as a surgical robot master interface. Yet due to the diversity of potential slave robots and surgical procedures, as well as the dynamic nature of surgery, it is challenging to make general conclusions from published accuracy and precision data. Thus, our goal in this paper is to explore the use of the Leap in the specific scenario of endonasal pituitary surgery. We use it to control a concentric tube continuum robot in a phantom study, and compare user performance using the Leap to previously published results using the Phantom Omni. We find that the users were able to achieve nearly identical average resection percentage and overall surgical duration with the Leap.

Initial Experiments with the Leap Motion as a User Interface in Robotic Endonasal Surgery

Science.gov (United States)

Travaglini, T. A.; Swaney, P. J.; Weaver, Kyle D.; Webster, R. J.

2016-01-01

The Leap Motion controller is a low-cost, optically-based hand tracking system that has recently been introduced on the consumer market. Prior studies have investigated its precision and accuracy, toward evaluating its usefulness as a surgical robot master interface. Yet due to the diversity of potential slave robots and surgical procedures, as well as the dynamic nature of surgery, it is challenging to make general conclusions from published accuracy and precision data. Thus, our goal in this paper is to explore the use of the Leap in the specific scenario of endonasal pituitary surgery. We use it to control a concentric tube continuum robot in a phantom study, and compare user performance using the Leap to previously published results using the Phantom Omni. We find that the users were able to achieve nearly identical average resection percentage and overall surgical duration with the Leap. PMID:26752501

Mobile robot motion estimation using Hough transform

Science.gov (United States)

Aldoshkin, D. N.; Yamskikh, T. N.; Tsarev, R. Yu

2018-05-01

This paper proposes an algorithm for estimation of mobile robot motion. The geometry of surrounding space is described with range scans (samples of distance measurements) taken by the mobile robot’s range sensors. A similar sample of space geometry in any arbitrary preceding moment of time or the environment map can be used as a reference. The suggested algorithm is invariant to isotropic scaling of samples or map that allows using samples measured in different units and maps made at different scales. The algorithm is based on Hough transform: it maps from measurement space to a straight-line parameters space. In the straight-line parameters, space the problems of estimating rotation, scaling and translation are solved separately breaking down a problem of estimating mobile robot localization into three smaller independent problems. The specific feature of the algorithm presented is its robustness to noise and outliers inherited from Hough transform. The prototype of the system of mobile robot orientation is described.

Stability analysis of multiple-robot control systems

Science.gov (United States)

Wen, John T.; Kreutz, Kenneth

1989-01-01

In a space telerobotic service scenario, cooperative motion and force control of multiple robot arms are of fundamental importance. Three paradigms to study this problem are proposed. They are distinguished by the set of variables used for control design. They are joint torques, arm tip force vectors, and an accelerated generalized coordinate set. Control issues related to each case are discussed. The latter two choices require complete model information, which presents practical modeling, computational, and robustness problems. Therefore, focus is on the joint torque control case to develop relatively model independent motion and internal force control laws. The rigid body assumption allows the motion and force control problems to be independently addressed. By using an energy motivated Lyapunov function, a simple proportional derivative plus gravity compensation type of motion control law is always shown to be stabilizing. The asymptotic convergence of the tracing error to zero requires the use of a generalized coordinate with the contact constraints taken into account. If a non-generalized coordinate is used, only convergence to a steady state manifold can be concluded. For the force control, both feedforward and feedback schemes are analyzed. The feedback control, if proper care has been taken, exhibits better robustness and transient performance.

The Rh-1 Full-Size Humanoid Robot: Design, Walking Pattern Generation and Control

Directory of Open Access Journals (Sweden)

M. Arbulú

2009-01-01

Full Text Available This paper is an overview of the humanoid robot Rh-1, the second phase of the Rh project, which was launched by the Robotics Lab at the Carlos III University of Madrid in 2002. The robot mechanical design includes the specifications development in order to construct a platform, which is capable of stable biped walking. At first, the robots’ weights were calculated in order to obtain the inverse dynamics and to select the actuators. After that, mechanical specifications were introduced in order to verify the robot’s structural behaviour with different experimental gaits. In addition, an important aspect is the joints design when their axes are crossed, which is called ‘Joints of Rectangular Axes’ (JRA. The problem with these joints is obtaining two or more degrees of freedom (DOF in small space. The construction of a humanoid robot also includes the design of hardware and software architectures. The main advantage of the proposed hardware and software architectures is the use of standardised solutions frequently used in the automation industry and commercially available hardware components. It provides scalability, modularity and application of standardised interfaces and brings the design of the complex control system of the humanoid robot out of a closed laboratory to industry. Stable walking is the most essential ability for the humanoid robot. The three dimensional Linear Inverted Pendulum Model (3D-LIPM and the Cart-table models had been used in order to achieve natural and dynamic biped walking. Humanoid dynamics is widely simplified by concentrating its mass in the centre of gravity (COG and moving it following the natural inverted pendulum laws (3D-LIPM or by controlling the cart motion (Cart-table model. An offline-calculated motion pattern does not guarantee the walking stability of the humanoid robot. Control architecture for the dynamic humanoid robot walking was developed, which is able to make online modifications of the

Modeling, system identification, and control for slosh-free motion of an open container of liquid

International Nuclear Information System (INIS)

Feddema, J.; Baty, R.; Dykhuizen, R.; Dohrmann, C.; Parker, G.; Robinett, R.; Romero, V.; Schmitt, D.

1996-04-01

This report discusses work performed under a Cooperative Research And Development Agreement (CRADA) with Corning, Inc., to analyze and test various techniques for controlling the motion of a high speed robotic arm carrying an open container of viscous liquid, in this case, molten glass. A computer model was generated to estimate the modes of oscillation of the liquid based on the shape of the container and the viscosity of the liquid. This fluid model was experimentally verified and tuned based on experimental data from a capacitive sensor on the side of the container. A model of the robot dynamics was also developed and verified through experimental tests on a Fanuc S-800 robot arm. These two models were used to estimate the overall modes of oscillation of an open container of liquid being carried by a robot arm. Using the estimated modes, inverse dynamic control techniques were used to determine a motion profile which would eliminate waves on the liquid's surface. Experimental tests showed that residual surface waves in an open container of water at the end of motion were reduced by over 95% and that in-motion surface waves were reduced by over 75%

Coordinated Resolved Motion Control of Dual-Arm Manipulators with Closed Chain

Directory of Open Access Journals (Sweden)

Tianliang Liu

2016-05-01

Full Text Available When applied to some tasks, such as payload handling, assembling, repairing and so on, the two arms of a humanoid robot will form a closed kinematic chain. It makes the motion planning and control for dual-arm coordination very complex and difficult. In this paper, we present three types of resolved motion control methods for a humanoid robot during coordinated manipulation. They are, respectively, position-level, velocity-level and acceleration-level resolved motion control methods. The desired pose, velocity and acceleration of each end-effector are then resolved according to the desired motion of the payload and the constraints on the closed-chain system without consideration of the internal force. Corresponding to the three cases above, the joint variables of each arm are then calculated using the inverse kinematic equations, at position-level, velocity-level or acceleration-level. Finally, a dynamic modelling and simulation platform is established based on ADAMS and Matlab software. The proposed methods are verified by typical cases. The simulation results show that the proposed control strategy can realize the dual-arm coordinated operation and the internal force of the closed chain during the operation is controlled in a reasonable range at the same time.

Development of position control of end-effector for CS-113 robot based on three degree of freedom motions

International Nuclear Information System (INIS)

Iqbal, Muhammad; Setiawan, Widi; Arif, Agus

2003-01-01

A software development for three degrees of freedom motions of CS-113 robot arm has been done. This software, which was based on inverse kinematic, can be used to control position of D and D (decontamination and Dismantlement) robot. A preliminary construction of robot arm (three degrees of freedom) has been constructed also to study the mechanic aspects. The scope of this research consist of direct kinematic and inverse kinematic implementation. The direct kinematic implementation developed according to following steps: (1) assigning kinematic parameters of CS-113 robot arm using Denavit-Hertenberg methods, (2) formulating kinematic equation for all joint. The inverse kinematic implementation developed by transforming position in Cartesian coordinates into joint angle in angle coordinates. Both direct and inverse kinematic were implemented with computer software which is written in the VISUAL BASIC. This software was tested on CS-113 robot. The theoretically calculation was done on MATLAB. Input of direct kinematic were joint angles (5 o , 10 o , -20 o , 15 o , 25 o , 30 o , -50 o , and 60 o ), whereas the input of inverse kinematic were the position on Cartesian coordinate, with the duration for moving end-effector testing 4 seconds. The test results of direct kinematic implementation on CS-113 robot were the position of end-effector on Cartesian coordinates. The position of end-effector which was measured experimentally on CS-113 robot compared with position of end-effector which was calculated on MATLAB. This comparison showed that static performance of CS-113 robot manipulator, bias (systematic error) that different from the end-effector position change within 8,9%, 12,3% and 27,3% on X, Y, Z axes, respectively, the measurements repeatability (precision) of end-effector position were ± 0,031 cm to ±0,183 cm. The test results of inverse kinematic implementation on CS-113 robot showed that the accuracy of end-effector position varied on all axes, the bias

Robot engineering

Energy Technology Data Exchange (ETDEWEB)

Jung, Seul

2006-02-15

This book deals with robot engineering, giving descriptions of robot's history, current tendency of robot field, work and characteristic of industrial robot, essential merit and vector, application of matrix, analysis of basic vector, expression of Denavit-Hartenberg, robot kinematics such as forward kinematics, inverse kinematics, cases of MATLAB program, and motion kinematics, robot kinetics like moment of inertia, centrifugal force and coriolis power, and Euler-Lagrangian equation course plan, SIMULINK position control of robots.

Robot engineering

International Nuclear Information System (INIS)

Jung, Seul

2006-02-01

This book deals with robot engineering, giving descriptions of robot's history, current tendency of robot field, work and characteristic of industrial robot, essential merit and vector, application of matrix, analysis of basic vector, expression of Denavit-Hartenberg, robot kinematics such as forward kinematics, inverse kinematics, cases of MATLAB program, and motion kinematics, robot kinetics like moment of inertia, centrifugal force and coriolis power, and Euler-Lagrangian equation course plan, SIMULINK position control of robots.

Affine Transform to Reform Pixel Coordinates of EOG Signals for Controlling Robot Manipulators Using Gaze Motions

Directory of Open Access Journals (Sweden)

Muhammad Ilhamdi Rusydi

2014-06-01

Full Text Available Biosignals will play an important role in building communication between machines and humans. One of the types of biosignals that is widely used in neuroscience are electrooculography (EOG signals. An EOG has a linear relationship with eye movement displacement. Experiments were performed to construct a gaze motion tracking method indicated by robot manipulator movements. Three operators looked at 24 target points displayed on a monitor that was 40 cm in front of them. Two channels (Ch1 and Ch2 produced EOG signals for every single eye movement. These signals were converted to pixel units by using the linear relationship between EOG signals and gaze motion distances. The conversion outcomes were actual pixel locations. An affine transform method is proposed to determine the shift of actual pixels to target pixels. This method consisted of sequences of five geometry processes, which are translation-1, rotation, translation-2, shear and dilatation. The accuracy was approximately 0.86° ± 0.67° in the horizontal direction and 0.54° ± 0.34° in the vertical. This system successfully tracked the gaze motions not only in direction, but also in distance. Using this system, three operators could operate a robot manipulator to point at some targets. This result shows that the method is reliable in building communication between humans and machines using EOGs.

Affine transform to reform pixel coordinates of EOG signals for controlling robot manipulators using gaze motions.

Science.gov (United States)

Rusydi, Muhammad Ilhamdi; Sasaki, Minoru; Ito, Satoshi

2014-06-10

Biosignals will play an important role in building communication between machines and humans. One of the types of biosignals that is widely used in neuroscience are electrooculography (EOG) signals. An EOG has a linear relationship with eye movement displacement. Experiments were performed to construct a gaze motion tracking method indicated by robot manipulator movements. Three operators looked at 24 target points displayed on a monitor that was 40 cm in front of them. Two channels (Ch1 and Ch2) produced EOG signals for every single eye movement. These signals were converted to pixel units by using the linear relationship between EOG signals and gaze motion distances. The conversion outcomes were actual pixel locations. An affine transform method is proposed to determine the shift of actual pixels to target pixels. This method consisted of sequences of five geometry processes, which are translation-1, rotation, translation-2, shear and dilatation. The accuracy was approximately 0.86° ± 0.67° in the horizontal direction and 0.54° ± 0.34° in the vertical. This system successfully tracked the gaze motions not only in direction, but also in distance. Using this system, three operators could operate a robot manipulator to point at some targets. This result shows that the method is reliable in building communication between humans and machines using EOGs.

Inverse kinematic-based robot control

Science.gov (United States)

Wolovich, W. A.; Flueckiger, K. F.

1987-01-01

A fundamental problem which must be resolved in virtually all non-trivial robotic operations is the well-known inverse kinematic question. More specifically, most of the tasks which robots are called upon to perform are specified in Cartesian (x,y,z) space, such as simple tracking along one or more straight line paths or following a specified surfacer with compliant force sensors and/or visual feedback. In all cases, control is actually implemented through coordinated motion of the various links which comprise the manipulator; i.e., in link space. As a consequence, the control computer of every sophisticated anthropomorphic robot must contain provisions for solving the inverse kinematic problem which, in the case of simple, non-redundant position control, involves the determination of the first three link angles, theta sub 1, theta sub 2, and theta sub 3, which produce a desired wrist origin position P sub xw, P sub yw, and P sub zw at the end of link 3 relative to some fixed base frame. Researchers outline a new inverse kinematic solution and demonstrate its potential via some recent computer simulations. They also compare it to current inverse kinematic methods and outline some of the remaining problems which will be addressed in order to render it fully operational. Also discussed are a number of practical consequences of this technique beyond its obvious use in solving the inverse kinematic question.

Neural-Network Control Of Prosthetic And Robotic Hands

Science.gov (United States)

Buckley, Theresa M.

1991-01-01

Electronic neural networks proposed for use in controlling robotic and prosthetic hands and exoskeletal or glovelike electromechanical devices aiding intact but nonfunctional hands. Specific to patient, who activates grasping motion by voice command, by mechanical switch, or by myoelectric impulse. Patient retains higher-level control, while lower-level control provided by neural network analogous to that of miniature brain. During training, patient teaches miniature brain to perform specialized, anthropomorphic movements unique to himself or herself.

A novel optimal coordinated control strategy for the updated robot system for single port surgery.

Science.gov (United States)

Bai, Weibang; Cao, Qixin; Leng, Chuntao; Cao, Yang; Fujie, Masakatsu G; Pan, Tiewen

2017-09-01

Research into robotic systems for single port surgery (SPS) has become widespread around the world in recent years. A new robot arm system for SPS was developed, but its positioning platform and other hardware components were not efficient. Special features of the developed surgical robot system make good teleoperation with safety and efficiency difficult. A robot arm is combined and used as new positioning platform, and the remote center motion is realized by a new method using active motion control. A new mapping strategy based on kinematics computation and a novel optimal coordinated control strategy based on real-time approaching to a defined anthropopathic criterion configuration that is referred to the customary ease state of human arms and especially the configuration of boxers' habitual preparation posture are developed. The hardware components, control architecture, control system, and mapping strategy of the robotic system has been updated. A novel optimal coordinated control strategy is proposed and tested. The new robot system can be more dexterous, intelligent, convenient and safer for preoperative positioning and intraoperative adjustment. The mapping strategy can achieve good following and representation for the slave manipulator arms. And the proposed novel control strategy can enable them to complete tasks with higher maneuverability, lower possibility of self-interference and singularity free while teleoperating. Copyright © 2017 John Wiley & Sons, Ltd.

Implementation of robust adaptive control for robotic manipulator using TMS320C30

International Nuclear Information System (INIS)

Han, S. H.

1996-01-01

A new adaptive digital control scheme for the robotic manipulator is proposed in this paper. Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion for robotic manipulators. In the proposed scheme, adaptation laws are derived from the improved Lyapunov second stability analysis based on the adaptive feedforward and feedback controller and PI type time-varying control elements. The control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot. (author)

Intelligent robot action planning

Energy Technology Data Exchange (ETDEWEB)

Vamos, T; Siegler, A

1982-01-01

Action planning methods used in intelligent robot control are discussed. Planning is accomplished through environment understanding, environment representation, task understanding and planning, motion analysis and man-machine communication. These fields are analysed in detail. The frames of an intelligent motion planning system are presented. Graphic simulation of the robot's environment and motion is used to support the planning. 14 references.

Robust trajectory tracking control of a dual-arm space robot actuated by control moment gyroscopes

Science.gov (United States)

Jia, Yinghong; Misra, Arun K.

2017-08-01

It is a new design concept to employ control moment gyroscopes (CMGs) as reactionless actuators for space robots. Such actuation has several noticeable advantages such as weak dynamical coupling and low power consumption over traditional joint motor actuation. This paper presents a robust control law for a CMG-actuated space robot in presence of system uncertainties and closed-chain constraints. The control objective is to make the manipulation variables to track the desired trajectories, and reduce the possibility of CMG saturation simultaneously. A reduced-order dynamical equation in terms of independent motion variables is derived using Kane's equations. Desired trajectories of the independent motion variables are derived by minimum-norm trajectory planning algorithm, and an adaptive sliding mode controller with improved adaptation laws is proposed to drive the independent motion variables tracking the desired trajectories. Uniformly ultimate boundedness of the closed loop system is proven using Lyapunov method. The redundancy of the full-order actual control torques is utilized to generate a null torque vector which reduces the possibility of CMG angular momentum saturation while producing no effect on the reduced-order control input. Simulation results demonstrate the effectiveness of the proposed algorithms and the advantage of weak dynamical coupling of the CMG-actuated system.

Analysis of the Accuracy and Robustness of the Leap Motion Controller

OpenAIRE

Weichert, Frank; Bachmann, Daniel; Rudak, Bartholomäus; Fisseler, Denis

2013-01-01

The Leap Motion Controller is a new device for hand gesture controlled user interfaces with declared sub-millimeter accuracy. However, up to this point its capabilities in real environments have not been analyzed. Therefore, this paper presents a first study of a Leap Motion Controller. The main focus of attention is on the evaluation of the accuracy and repeatability. For an appropriate evaluation, a novel experimental setup was developed making use of an industrial robot with a reference pe...

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.

A New Conflict Resolution Method for Multiple Mobile Robots in Cluttered Environments With Motion-Liveness.

Science.gov (United States)

Shahriari, Mohammadali; Biglarbegian, Mohammad

2018-01-01

This paper presents a new conflict resolution methodology for multiple mobile robots while ensuring their motion-liveness, especially for cluttered and dynamic environments. Our method constructs a mathematical formulation in a form of an optimization problem by minimizing the overall travel times of the robots subject to resolving all the conflicts in their motion. This optimization problem can be easily solved through coordinating only the robots' speeds. To overcome the computational cost in executing the algorithm for very cluttered environments, we develop an innovative method through clustering the environment into independent subproblems that can be solved using parallel programming techniques. We demonstrate the scalability of our approach through performing extensive simulations. Simulation results showed that our proposed method is capable of resolving the conflicts of 100 robots in less than 1.23 s in a cluttered environment that has 4357 intersections in the paths of the robots. We also developed an experimental testbed and demonstrated that our approach can be implemented in real time. We finally compared our approach with other existing methods in the literature both quantitatively and qualitatively. This comparison shows while our approach is mathematically sound, it is more computationally efficient, scalable for very large number of robots, and guarantees the live and smooth motion of robots.

A new robotic needle insertion method to minimise attendant prostate motion

International Nuclear Information System (INIS)

Lagerburg, Vera; Moerland, Marinus A.; Vulpen, Marco van; Lagendijk, Jan J.W.

2006-01-01

Background and purpose: The purpose of this study is to investigate the efficacy of a new needle insertion method (tapping instead of pushing) in reducing attendant tissue motion. This can be useful in applications where tissue motion due to needle insertion is problematic such as e.g. MRI-guided prostate brachytherapy and breast biopsies. In this study we will focus on prostate motion due to needle insertion. Material and methods: Prostate motion due to needle insertion was measured in 30 patients, who were transperineally implanted with fiducial gold markers for position verification in prostate intensity modulated radiotherapy. In total 32 needles were manually pushed into the prostate and 29 were tapped with a prototype robotic system. The prostate motion in the cranio-caudal direction was measured on the video record of the ultrasound images. Differences in prostate motion between the two needle insertion methods were analysed making use of SPSS. Results: The mean prostate motion was 5.6 mm (range 0.3-21.6) when the needle was pushed and 0.9 mm (range 0-2.0) when the needle was tapped into the prostate (p < 0.001). Conclusion: Prostate motion was significantly less when the needle was tapped into the prostate compared to when the needle was pushed. This result is important for the development of a tapping, MRI-guided, prostate implant robotic system

Humanoid Walking Robot: Modeling, Inverse Dynamics, and Gain Scheduling Control

Directory of Open Access Journals (Sweden)

Elvedin Kljuno

2010-01-01

Full Text Available This article presents reference-model-based control design for a 10 degree-of-freedom bipedal walking robot, using nonlinear gain scheduling. The main goal is to show concentrated mass models can be used for prediction of the required joint torques for a bipedal walking robot. Relatively complicated architecture, high DOF, and balancing requirements make the control task of these robots difficult. Although linear control techniques can be used to control bipedal robots, nonlinear control is necessary for better performance. The emphasis of this work is to show that the reference model can be a bipedal walking model with concentrated mass at the center of gravity, which removes the problems related to design of a pseudo-inverse system. Another significance of this approach is the reduced calculation requirements due to the simplified procedure of nominal joint torques calculation. Kinematic and dynamic analysis is discussed including results for joint torques and ground force necessary to implement a prescribed walking motion. This analysis is accompanied by a comparison with experimental data. An inverse plant and a tracking error linearization-based controller design approach is described. We propose a novel combination of a nonlinear gain scheduling with a concentrated mass model for the MIMO bipedal robot system.

Design and implementation of motion planning of inspection and maintenance robot for ITER-like vessel

Energy Technology Data Exchange (ETDEWEB)

Wang, Hesheng; Lai, Yinping [Department of Automation, Shanghai Jiao Tong University, Shanghai 200240 (China); Key Laboratory of System Control and Information Processing, Ministry of Education of China (China); Chen, Weidong, E-mail: wdchen@sjtu.edu.cn [Department of Automation, Shanghai Jiao Tong University, Shanghai 200240 (China); Key Laboratory of System Control and Information Processing, Ministry of Education of China (China); Cao, Qixin [Institute of Robotics, Shanghai Jiao Tong University, Shanghai 200240 (China)

2015-12-15

Robot motion planning is a fundamental problem to ensure the robot executing the task without clashes, fast and accurately in a special environment. In this paper, a motion planning of a 12 DOFs remote handling robot used for inspecting the working state of the ITER-like vessel and maintaining key device components is proposed and implemented. Firstly, the forward and inverse kinematics are given by analytic method. The work space and posture space of this manipulator are both considered. Then the motion planning is divided into three stages: coming out of the cassette mover, moving along the in-vessel center line, and inspecting the D-shape section. Lastly, the result of experiments verified the performance of the motion design method. In addition, the task of unscrewing/screwing the screw demonstrated the feasibility of system in function.

Vision based motion control for a humanoid head

NARCIS (Netherlands)

Visser, L.C.; Carloni, Raffaella; Stramigioli, Stefano

2009-01-01

This paper describes the design of a motion control algorithm for a humanoid robotic head, which consists of a neck with four degrees of freedom and two eyes (a stereo pair system) that tilt on a common axis and rotate sideways freely. The kinematic and dynamic properties of the head are analyzed

Study on State Transition Method Applied to Motion Planning for a Humanoid Robot

Directory of Open Access Journals (Sweden)

Xuyang Wang

2008-11-01

Full Text Available This paper presents an approach of motion planning for a humanoid robot using a state transition method. In this method, motion planning is simplified by introducing a state-space to describe the whole motion series. And each state in the state-space corresponds to a contact state specified during the motion. The continuous motion is represented by a sequence of discrete states. The concept of the transition between two neighboring states, that is the state transition, can be realized by using some traditional path planning methods. Considering the dynamical stability of the robot, a state transition method based on search strategy is proposed. Different sets of trajectories are generated by using a variable 5th-order polynomial interpolation method. After quantifying the stabilities of these trajectories, the trajectories with the largest stability margin are selected as the final state transition trajectories. Rising motion process is exemplified to validate the method and the simulation results show the proposed method to be feasible and effective.

Using real-time stereopsis for mobile robot control

Science.gov (United States)

Bonasso, R. P.; Nishihara, H. K.

1991-02-01

This paper describes on-going work in using range and motion data generated at video-frame rates as the basis for long-range perception in a mobile robot. A current approach in the artificial intelligence community to achieve timecritical perception for situated reasoning is to use low-level perception for motor reflex-like activity and higher-level but more computationally intense perception for path planning reconnaissance and retrieval activities. Typically inclinometers and a compass or an infra-red beacon system provide stability and orientation maintenance and ultrasonic or infra-red sensors serve as proximity detectors for obstacle avoidance. For distant ranging and area occupancy determination active imaging systems such as laser scanners can be prohibitivtly expensive and heretofore passive systems typically performed more slowly than the cycle time of the control system causing the robot to halt periodically along its way. However a recent stereo system developed by Nishihara known as PRISM (Practical Real-time Imaging Stereo Matcher) matches stereo pairs using a sign-correlation technique that gives range and motion at video frame rates. We are integrating this technique with constant-time control software for distant ranging and object detection at a speed that is comparable with the cycle-times of the low-level sensors. Possibilities for a variety of uses in a leader-follower mobile robot situation are discussed.

Removal of proprioception by BCI raises a stronger body ownership illusion in control of a humanlike robot.

Science.gov (United States)

Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi

2016-09-22

Body ownership illusions provide evidence that our sense of self is not coherent and can be extended to non-body objects. Studying about these illusions gives us practical tools to understand the brain mechanisms that underlie body recognition and the experience of self. We previously introduced an illusion of body ownership transfer (BOT) for operators of a very humanlike robot. This sensation of owning the robot's body was confirmed when operators controlled the robot either by performing the desired motion with their body (motion-control) or by employing a brain-computer interface (BCI) that translated motor imagery commands to robot movement (BCI-control). The interesting observation during BCI-control was that the illusion could be induced even with a noticeable delay in the BCI system. Temporal discrepancy has always shown critical weakening effects on body ownership illusions. However the delay-robustness of BOT during BCI-control raised a question about the interaction between the proprioceptive inputs and delayed visual feedback in agency-driven illusions. In this work, we compared the intensity of BOT illusion for operators in two conditions; motion-control and BCI-control. Our results revealed a significantly stronger BOT illusion for the case of BCI-control. This finding highlights BCI's potential in inducing stronger agency-driven illusions by building a direct communication between the brain and controlled body, and therefore removing awareness from the subject's own body.

Study on fundamental mechanism of nuclear advanced robot. An analysis of fundamental motion with pliability for end-effector of advanced robot

International Nuclear Information System (INIS)

Ohki, Arahiko; Hirano, Sigeo; Yoshida, Tomoya.

1997-01-01

Most of present robots only perform works simulating human action, but hereafter, it is required to do advanced works smoothly with robots in place of men. Among the mechanisms of high performance robots, as one of the important components that do advanced action and adapt to diversified purposes, there is manipulator. The manipulator comprises arm and end effector. In the process of heightening robot performance hereafter, the reproduction of detailed action is the indispensable subject of research. The object of carrying out this research is to elucidate the possibility of giving the functions close to those of delicate human hands to end effector. First, the joints of human hands were measured, and based on these data, the equation for determining the change of angle in relation to the time of motion of respective joints was established. Further, the simulation of simple actions was carried out, and the concept of the mechanism model was built by analyzing the motion similar to human body. The structural difference in the joints of human and manipulator, the measurement of hands and the analysis of the motion of hand joints are reported. (K.I.)

Velocity and Motion Control of a Self-Balancing Vehicle Based on a Cascade Control Strategy

Directory of Open Access Journals (Sweden)

Miguel Velazquez

2016-06-01

Full Text Available This paper presents balancing, velocity and motion control of a self-balancing vehicle. A cascade controller is implemented for both balancing control and angular velocity control. This controller is tested in simulations using a proposed mathematical model of the system. Motion control is achieved based on the kinematics of the robot. Control hardware is designed and integrated to implement the proposed controllers. Pitch is kept under 1° from the equilibrium position with no external disturbances. The linear cascade control is able to handle slight changes in the system dynamics, such as in the centre of mass and the slope on an inclined surface.

Modeling and Control of a Dragonfly-Like Robot

Directory of Open Access Journals (Sweden)

Micael S. Couceiro

2010-01-01

Full Text Available Dragonflies demonstrate unique and superior flight performances than most of the other insect species and birds. They are equipped with two pairs of independently controlled wings granting an unmatchable flying performance and robustness. In this paper, the dynamics of a dragonfly-inspired robot is studied. The system performance is analyzed in terms of time response and robustness. The development of computational simulation based on the dynamics of the robotic dragonfly allows the test of different control algorithms. We study different movements, the dynamics, and the level of dexterity in wing motion of the dragonfly. The results are positive for the construction of flying platforms that effectively mimic the kinematics and dynamics of dragonflies and potentially exhibit superior flight performance than existing flying platforms.

An Integrated Framework for Human-Robot Collaborative Manipulation.

Science.gov (United States)

Sheng, Weihua; Thobbi, Anand; Gu, Ye

2015-10-01

This paper presents an integrated learning framework that enables humanoid robots to perform human-robot collaborative manipulation tasks. Specifically, a table-lifting task performed jointly by a human and a humanoid robot is chosen for validation purpose. The proposed framework is split into two phases: 1) phase I-learning to grasp the table and 2) phase II-learning to perform the manipulation task. An imitation learning approach is proposed for phase I. In phase II, the behavior of the robot is controlled by a combination of two types of controllers: 1) reactive and 2) proactive. The reactive controller lets the robot take a reactive control action to make the table horizontal. The proactive controller lets the robot take proactive actions based on human motion prediction. A measure of confidence of the prediction is also generated by the motion predictor. This confidence measure determines the leader/follower behavior of the robot. Hence, the robot can autonomously switch between the behaviors during the task. Finally, the performance of the human-robot team carrying out the collaborative manipulation task is experimentally evaluated on a platform consisting of a Nao humanoid robot and a Vicon motion capture system. Results show that the proposed framework can enable the robot to carry out the collaborative manipulation task successfully.

Tracking Control of A Balancing Robot – A Model-Based Approach

Directory of Open Access Journals (Sweden)

Zaiczek Tobias

2014-08-01

Full Text Available This paper presents a control concept for a single-axle mobile robot moving on the horizontal plane. A mathematical model of the nonholonomic mechanical system is derived using Hamel's equations of motion. Subsequently, a concept for a tracking controller is described in detail. This controller keeps the mobile robot on a given reference trajectory while maintaining it in an upright position. The control objective is reached by a cascade control structure. By an appropriate input transformation, we are able to utilize an input-output linearization of a subsystem. For the remaining dynamics a linear set-point control law is presented. Finally, the performance of the implemented control law is illustrated by simulation results.

An overview on real-time control schemes for wheeled mobile robot

Science.gov (United States)

Radzak, M. S. A.; Ali, M. A. H.; Sha’amri, S.; Azwan, A. R.

2018-04-01

The purpose of this paper is to review real-time control motion algorithms for wheeled mobile robot (WMR) when navigating in environment such as road. Its need a good controller to avoid collision with any disturbance and maintain a track error at zero level. The controllers are used with other aiding sensors to measure the WMR’s velocities, posture, and interference to estimate the required torque to be applied on the wheels of mobile robot. Four main categories for wheeled mobile robot control systems have been found in literature which are namely: Kinematic based controller, Dynamic based controllers, artificial intelligence based control system, and Active Force control. A MATLAB/Simulink software is the main software to simulate and implement the control system. The real-time toolbox in MATLAB/SIMULINK are used to receive/send data from sensors/to actuator with presence of disturbances, however others software such C, C++ and visual basic are rare to be used.

Design and control of five fingered under-actuated robotic hand

Science.gov (United States)

Sahoo, Biswojit; Parida, Pramod Kumar

2018-04-01

Now a day's research regarding humanoid robots and its application in different fields (industry, household, rehabilitation and exploratory) is going on entire the globe. Among which a challenging topic is to design a dexterous robotic hand which not only can perform as a hand of a robot but also can be used in re habilitation. The basic key concern is a dexterous robot hand which can be able to mimic the function of biological hand to perform different operations. This thesis work is regarding design and control of a under-actuated robotic hand consisting of four under actuated fingers (index finger, middle finger, little finger and ring finger ) , a thumb and a dexterous palm which can copy the motions and grasp type of human hand which having 21degrees of freedom instead of 25Degree Of Freedom.

Multi-objective Design Optimization of a Parallel Schönflies-motion Robot

DEFF Research Database (Denmark)

Wu, Guanglei; Bai, Shaoping; Hjørnet, Preben

2016-01-01

. The dynamic performance is concerned mainly the capability of force transmission in the parallel kinematic chain, for which transmission indices are defined. The Pareto-front is obtained to investigate the influence of the design variables to the robot performance. Dynamic characteristics for three Pareto......This paper introduces a parallel Schoenflies-motion robot with rectangular workspace, which is suitable for pick-and-place operations. A multi-objective optimization problem is formulated to optimize the robot's geometric parameters with consideration of kinematic and dynamic performances...

Motion Intention Analysis-Based Coordinated Control for Amputee-Prosthesis Interaction

Directory of Open Access Journals (Sweden)

Fei Wang

2010-01-01

Full Text Available To study amputee-prosthesis (AP interaction, a novel reconfigurable biped robot was designed and fabricated. In homogeneous configuration, two identical artificial legs (ALs were used to simulate the symmetrical lower limbs of a healthy person. Linear inverted pendulum model combining with ZMP stability criterion was used to generate the gait trajectories of ALs. To acquire interjoint coordination for healthy gait, rate gyroscopes were mounted on CoGs of thigh and shank of both legs. By employing principal component analysis, the measured angular velocities were processed and the motion synergy was obtained in the final. Then, one of two ALs was replaced by a bionic leg (BL, and the biped robot was changed into heterogeneous configuration to simulate the AP coupling system. To realize symmetrical stable walking, master/slave coordinated control strategy is proposed. According to information acquired by gyroscopes, BL recognized the motion intention of AL and reconstructed its kinematic variables based on interjoint coordination. By employing iterative learning control, gait tracking of BL to AL was archived. Real environment robot walking experiments validated the correctness and effectiveness of the proposed scheme.

Automation of pharmaceutical warehouse using groups robots with remote climate control and video surveillance

OpenAIRE

Zhuravska, I. M.; Popel, M. I.

2015-01-01

In this paper, we present a complex solution for automation pharmaceutical warehouse, including the implementation of climate-control, video surveillance with remote access to video, robotics selection of medicine with the optimization of the robot motion. We describe all the elements of local area network (LAN) necessary to solve all these problems.

Application of model based control to robotic manipulators

Science.gov (United States)

Petrosky, Lyman J.; Oppenheim, Irving J.

1988-01-01

A robot that can duplicate humam motion capabilities in such activities as balancing, reaching, lifting, and moving has been built and tested. These capabilities are achieved through the use of real time Model-Based Control (MBC) techniques which have recently been demonstrated. MBC accounts for all manipulator inertial forces and provides stable manipulator motion control even at high speeds. To effectively demonstrate the unique capabilities of MBC, an experimental robotic manipulator was constructed, which stands upright, balancing on a two wheel base. The mathematical modeling of dynamics inherent in MBC permit the control system to perform functions that are impossible with conventional non-model based methods. These capabilities include: (1) Stable control at all speeds of operation; (2) Operations requiring dynamic stability such as balancing; (3) Detection and monitoring of applied forces without the use of load sensors; (4) Manipulator safing via detection of abnormal loads. The full potential of MBC has yet to be realized. The experiments performed for this research are only an indication of the potential applications. MBC has no inherent stability limitations and its range of applicability is limited only by the attainable sampling rate, modeling accuracy, and sensor resolution. Manipulators could be designed to operate at the highest speed mechanically attainable without being limited by control inadequacies. Manipulators capable of operating many times faster than current machines would certainly increase productivity for many tasks.

Hybrid magnetic mechanism for active locomotion based on inchworm motion

International Nuclear Information System (INIS)

Kim, Sung Hoon; Hashi, Shuichiro; Ishiyama, Kazushi

2013-01-01

Magnetic robots have been studied in the past. Insect-type micro-robots are used in various biomedical applications; researchers have developed inchworm micro-robots for endoscopic use. A biological inchworm has a looping locomotion gait. However, most inchworm micro-robots depend on a general bending, or bellows, motion. In this paper, we introduce a new robotic mechanism using magnetic force and torque control in a rotating magnetic field for a looping gait. The proposed robot is controlled by the magnetic torque, attractive force, and body mechanisms (two stoppers, flexible body, and different frictional legs). The magnetic torque generates a general bending motion. In addition, the attractive force and body mechanisms produce the robot’s looping motion within a rotating magnetic field and without the use of an algorithm for field control. We verified the device’s performance and analyzed the motion through simulations and various experiments. The robot mechanism can be applied to active locomotion for various medical robots, such as wireless endoscopes. (technical note)

Implementation of Motion Simulation Software and Visual-Auditory Electronics for Use in a Low Gravity Robotic Testbed

Science.gov (United States)

Martin, William Campbell

2011-01-01

The Jet Propulsion Laboratory (JPL) is developing the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) to assist in manned space missions. One of the proposed targets for this robotic vehicle is a near-Earth asteroid (NEA), which typically exhibit a surface gravity of only a few micro-g. In order to properly test ATHLETE in such an environment, the development team has constructed an inverted Stewart platform testbed that acts as a robotic motion simulator. This project focused on creating physical simulation software that is able to predict how ATHLETE will function on and around a NEA. The corresponding platform configurations are calculated and then passed to the testbed to control ATHLETE's motion. In addition, imitation attitude, imitation attitude control thrusters were designed and fabricated for use on ATHLETE. These utilize a combination of high power LEDs and audio amplifiers to provide visual and auditory cues that correspond to the physics simulation.

Design, Modeling and Control of a Biped Line-Walking Robot

Directory of Open Access Journals (Sweden)

Ludan Wang

2010-12-01

Full Text Available The subject of this paper is the design and analysis of a biped line walking robot for inspection of power transmission lines. With a novel mechanism the centroid of the robot can be concentrated on the axis of hip joint to minimize the drive torque of the hip joint. The mechanical structure of the robot is discussed, as well as forward kinematics. Dynamic model is established in this paper to analyze the inverse kinematics for motion planning. The line-walking cycle of the line-walking robot is composed of a single-support phase and a double-support phase. Locomotion of the line-walking robot is discussed in details and the obstacle-navigation process is planed according to the structure of power transmission line. To fulfill the demands of line-walking, a control system and trajectories generation method are designed for the prototype of the line-walking robot. The feasibility of this concept is then confirmed by performing experiments with a simulated line environment.

New Jacobian Matrix and Equations of Motion for a 6 d.o.f Cable-Driven Robot

Directory of Open Access Journals (Sweden)

Ali Afshari

2007-03-01

Full Text Available In this paper, we introduce a new method and new motion variables to study kinematics and dynamics of a 6 d.o.f cable-driven robot. Using these new variables and Lagrange equations, we achieve new equations of motion which are different in appearance and several aspects from conventional equations usually used to study 6 d.o.f cable robots. Then, we introduce a new Jacobian matrix which expresses kinematical relations of the robot via a new approach and is basically different from the conventional Jacobian matrix. One of the important characteristics of the new method is computational efficiency in comparison with the conventional method. It is demonstrated that using the new method instead of the conventional one, significantly reduces the computation time required to determine workspace of the robot as well as the time required to solve the equations of motion.

Adaptive neural control for dual-arm coordination of humanoid robot with unknown nonlinearities in output mechanism.

Science.gov (United States)

Liu, Zhi; Chen, Ci; Zhang, Yun; Chen, C L P

2015-03-01

To achieve an excellent dual-arm coordination of the humanoid robot, it is essential to deal with the nonlinearities existing in the system dynamics. The literatures so far on the humanoid robot control have a common assumption that the problem of output hysteresis could be ignored. However, in the practical applications, the output hysteresis is widely spread; and its existing limits the motion/force performances of the robotic system. In this paper, an adaptive neural control scheme, which takes the unknown output hysteresis and computational efficiency into account, is presented and investigated. In the controller design, the prior knowledge of system dynamics is assumed to be unknown. The motion error is guaranteed to converge to a small neighborhood of the origin by Lyapunov's stability theory. Simultaneously, the internal force is kept bounded and its error can be made arbitrarily small.

Usability Assessment of Two Different Control Modes for the Master Console of a Laparoscopic Surgical Robot

Directory of Open Access Journals (Sweden)

Xiaoli Zhang

2012-01-01

Full Text Available The objective of this study is to evaluate potential interface control modes for a compact four-degree-of-freedom (4-DOF surgical robot. The goal is to improve robot usability by incorporating a sophisticated haptics-capable interface. Two control modes were developed using a commercially available haptic joystick: (1 a virtually point-constrained interface providing an analog for constrained laparoscopic motion (3-DOF rotation and 1-DOF translation, and (2 an unconstrained Cartesian input interface mapping more directly to the surgical tool tip motions. Subjects (n = 5 successfully performed tissue identification and manipulation tasks in an animal model in point-constrained and unconstrained control modes, respectively, with speed roughly equal to that achieved in similar manual procedures, and without a steep learning curve. The robot control was evaluated through bench-top tests and a subsequent qualitative questionnaire (n = 15. The results suggest that the unconstrained control mode was preferred for both camera guidance and tool manipulations.

Effects of Rotational Motion in Robotic Needle Insertion

Science.gov (United States)

Ramezanpour, H.; Yousefi, H.; Rezaei, M.; Rostami, M.

2015-01-01

Background Robotic needle insertion in biological tissues has been known as one the most applicable procedures in sampling, robotic injection and different medical therapies and operations. Objective In this paper, we would like to investigate the effects of angular velocity in soft tissue insertion procedure by considering force-displacement diagram. Non-homogenous camel liver can be exploited as a tissue sample under standard compression test with Zwick/Roell device employing 1-D axial load-cell. Methods Effects of rotational motion were studied by running needle insertion experiments in 5, 50 and 200 mm/min in two types of with or without rotational velocity of 50, 150 and 300 rpm. On further steps with deeper penetrations, friction force of the insertion procedure in needle shaft was acquired by a definite thickness of the tissue. Results Designed mechanism of fixture for providing different frequencies of rotational motion is available in this work. Results for comparison of different force graphs were also provided. Conclusion Derived force-displacement graphs showed a significant difference between two procedures; however, tissue bleeding and disorganized micro-structure would be among unavoidable results. PMID:26688800

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.

Concurrent Path Planning with One or More Humanoid Robots

Science.gov (United States)

Sanders, Adam M. (Inventor); Reiland, Matthew J. (Inventor)

2014-01-01

A robotic system includes a controller and one or more robots each having a plurality of robotic joints. Each of the robotic joints is independently controllable to thereby execute a cooperative work task having at least one task execution fork, leading to multiple independent subtasks. The controller coordinates motion of the robot(s) during execution of the cooperative work task. The controller groups the robotic joints into task-specific robotic subsystems, and synchronizes motion of different subsystems during execution of the various subtasks of the cooperative work task. A method for executing the cooperative work task using the robotic system includes automatically grouping the robotic joints into task-specific subsystems, and assigning subtasks of the cooperative work task to the subsystems upon reaching a task execution fork. The method further includes coordinating execution of the subtasks after reaching the task execution fork.

Design and modeling of an autonomous multi-link snake robot, capable of 3D-motion

Directory of Open Access Journals (Sweden)

Rizkallah Rabel

2016-01-01

Full Text Available The paper presents the design of an autonomous, wheeless, mechanical snake robot that was modeled and built at Notre Dame University – Louaize. The robot is also capable of 3D motion with an ability to climb in the z-direction. The snake is made of a series links, each containing one to three high torque DC motors and a gearing system. They are connected to each other through Aluminum hollow rods that can be rotated through a 180° span. This allows the snake to move in various environments including unfriendly and cluttered ones. The front link has a proximity sensor used to map the environment. This mapping is sent to a microcontroller which controls and adapts the motion pattern of the snake. The snake can therefore choose to avoid obstacles, or climb over them if their height is within its range. The presented model is made of five links, but this number can be increased as their role is repetitive. The novel design is meant to overcome previous limitations by allowing 3D motion through electric actuators and low energy consumption.

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

International Nuclear Information System (INIS)

Pin, Francois G.

2003-01-01

Our overall objective is the development of a generalized methodology and code for the automated generation of the kinematics equations of robots and for the analytical solution of their motion planning equations subject to time-varying constraints, behavioral objectives and modular configuration

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

International Nuclear Information System (INIS)

Pin, Grancois G.

2004-01-01

Our overall objective is the development of a generalized methodology and code for the automated generation of the kinematics equations of robots and for the analytical solution of their motion planning equations subject to time-varying constraints, behavioral objectives, and modular configuration

Robot vision

International Nuclear Information System (INIS)

Hall, E.L.

1984-01-01

Almost all industrial robots use internal sensors such as shaft encoders which measure rotary position, or tachometers which measure velocity, to control their motions. Most controllers also provide interface capabilities so that signals from conveyors, machine tools, and the robot itself may be used to accomplish a task. However, advanced external sensors, such as visual sensors, can provide a much greater degree of adaptability for robot control as well as add automatic inspection capabilities to the industrial robot. Visual and other sensors are now being used in fundamental operations such as material processing with immediate inspection, material handling with adaption, arc welding, and complex assembly tasks. A new industry of robot vision has emerged. The application of these systems is an area of great potential

Estimating anatomical wrist joint motion with a robotic exoskeleton.

Science.gov (United States)

Rose, Chad G; Kann, Claudia K; Deshpande, Ashish D; O'Malley, Marcia K

2017-07-01

Robotic exoskeletons can provide the high intensity, long duration targeted therapeutic interventions required for regaining motor function lost as a result of neurological injury. Quantitative measurements by exoskeletons have been proposed as measures of rehabilitative outcomes. Exoskeletons, in contrast to end effector designs, have the potential to provide a direct mapping between human and robot joints. This mapping rests on the assumption that anatomical axes and robot axes are aligned well, and that movement within the exoskeleton is negligible. These assumptions hold well for simple one degree-of-freedom joints, but may not be valid for multi-articular joints with unique musculoskeletal properties such as the wrist. This paper presents an experiment comparing robot joint kinematic measurements from an exoskeleton to anatomical joint angles measured with a motion capture system. Joint-space position measurements and task-space smoothness metrics were compared between the two measurement modalities. The experimental results quantify the error between joint-level position measurements, and show that exoskeleton kinematic measurements preserve smoothness characteristics found in anatomical measures of wrist movements.

Open core control software for surgical robots.

Science.gov (United States)

Arata, Jumpei; Kozuka, Hiroaki; Kim, Hyung Wook; Takesue, Naoyuki; Vladimirov, B; Sakaguchi, Masamichi; Tokuda, Junichi; Hata, Nobuhiko; Chinzei, Kiyoyuki; Fujimoto, Hideo

2010-05-01

techniques for this purpose were introduced. Virtual fixture is well known technique as a "force guide" for supporting operators to perform precise manipulation by using a master-slave robot. The virtual fixture for precise and safety surgery was implemented on the system to demonstrate an idea of high-level collaboration between a surgical robot and a navigation system. The extension of virtual fixture is not a part of the Open Core Control system, however, the function such as virtual fixture cannot be realized without a tight collaboration between cutting-edge medical devices. By using the virtual fixture, operators can pre-define an accessible area on the navigation system, and the area information can be transferred to the robot. In this manner, the surgical console generates the reflection force when the operator tries to get out from the pre-defined accessible area during surgery. The Open Core Control software was implemented on a surgical master-slave robot and stable operation was observed in a motion test. The tip of the surgical robot was displayed on a navigation system by connecting the surgical robot with a 3D position sensor through the OpenIGTLink. The accessible area was pre-defined before the operation, and the virtual fixture was displayed as a "force guide" on the surgical console. In addition, the system showed stable performance in a duration test with network disturbance. In this paper, a design of the Open Core Control software for surgical robots and the implementation of virtual fixture were described. The Open Core Control software was implemented on a surgical robot system and showed stable performance in high-level collaboration works. The Open Core Control software is developed to be a widely used platform of surgical robots. Safety issues are essential for control software of these complex medical devices. It is important to follow the global specifications such as a FDA requirement "General Principles of Software Validation" or IEC62304. For

Distributed power and control actuation in the thoracic mechanics of a robotic insect

International Nuclear Information System (INIS)

Finio, Benjamin M; Wood, Robert J

2010-01-01

Recent advances in the understanding of biological flight have inspired roboticists to create flapping-wing vehicles on the scale of insects and small birds. While our understanding of the wing kinematics, flight musculature and neuromotor control systems of insects has expanded, in practice it has proven quite difficult to construct an at-scale mechanical device capable of similar flight performance. One of the key challenges is the development of an effective and efficient transmission mechanism to control wing motions. Here we present multiple insect-scale robotic thorax designs capable of producing asymmetric wing kinematics similar to those observed in nature and utilized by dipteran insects to maneuver. Inspired by the thoracic mechanics of dipteran insects, which entail a morphological separation of power and control muscles, these designs show that such distributed actuation can also modulate wing motion in a robotic design.

Distributed power and control actuation in the thoracic mechanics of a robotic insect.

Science.gov (United States)

Finio, Benjamin M; Wood, Robert J

2010-12-01

Recent advances in the understanding of biological flight have inspired roboticists to create flapping-wing vehicles on the scale of insects and small birds. While our understanding of the wing kinematics, flight musculature and neuromotor control systems of insects has expanded, in practice it has proven quite difficult to construct an at-scale mechanical device capable of similar flight performance. One of the key challenges is the development of an effective and efficient transmission mechanism to control wing motions. Here we present multiple insect-scale robotic thorax designs capable of producing asymmetric wing kinematics similar to those observed in nature and utilized by dipteran insects to maneuver. Inspired by the thoracic mechanics of dipteran insects, which entail a morphological separation of power and control muscles, these designs show that such distributed actuation can also modulate wing motion in a robotic design.

A Dynamic Non Energy Storing Guidance Constraint with Motion Redirection for Robot Assisted Surgery

Science.gov (United States)

2016-12-01

move during the operation. Robot -assisted beating heart surgery is an example of procedures that can benefit from dynamic constraints. Their...A Dynamic Non-Energy-Storing Guidance Constraint with Motion Redirection for Robot -Assisted Surgery Nima Enayati, Eva C. Alves Costa, Giancarlo...Momi, and G. Ferrigno, “Haptics in Robot -Assisted Surgery : Challenges and Benefits,” IEEE Rev. Biomed. Eng., 2016. [2] L. B. Rosenberg, “Virtual

Motion Planning for a Direct Metal Deposition Rapid Prototyping System

Energy Technology Data Exchange (ETDEWEB)

AMES,ARLO L.; HENSINGER,DAVID M.; KUHLMANN,JOEL L.

1999-10-18

A motion planning strategy was developed and implemented to generate motion control instructions from solid model data for controlling a robotically driven solid free-form fabrication process. The planning strategy was tested using a PUMA type robot arm integrated into a LENS{trademark} (Laser Engineered Net Shape) system. Previous systems relied on a series of x, y, and z stages, to provide a minimal coordinated motion control capability. This limited the complexity of geometries that could be constructed. With the coordinated motion provided by a robotic arm, the system can produce three dimensional parts by ''writing'' material onto any face of existing material. The motion planning strategy relied on solid model geometry evaluation and exploited robotic positioning flexibility to allow the construction of geometrically complex parts. The integration of the robotic manipulator into the LENS{trademark} system was tested by producing metal parts directly from CAD models.

Complete Low-Cost Implementation of a Teleoperated Control System for a Humanoid Robot

Directory of Open Access Journals (Sweden)

Rafael Barea

2013-01-01

Full Text Available Humanoid robotics is a field of a great research interest nowadays. This work implements a low-cost teleoperated system to control a humanoid robot, as a first step for further development and study of human motion and walking. A human suit is built, consisting of 8 sensors, 6 resistive linear potentiometers on the lower extremities and 2 digital accelerometers for the arms. The goal is to replicate the suit movements in a small humanoid robot. The data from the sensors is wirelessly transmitted via two ZigBee RF configurable modules installed on each device: the robot and the suit. Replicating the suit movements requires a robot stability control module to prevent falling down while executing different actions involving knees flexion. This is carried out via a feedback control system with an accelerometer placed on the robot’s back. The measurement from this sensor is filtered using Kalman. In addition, a two input fuzzy algorithm controlling five servo motors regulates the robot balance. The humanoid robot is controlled by a medium capacity processor and a low computational cost is achieved for executing the different algorithms. Both hardware and software of the system are based on open platforms. The successful experiments carried out validate the implementation of the proposed teleoperated system.

A study on optimal motion for a robot manipulator amid obstacles

International Nuclear Information System (INIS)

Park, Jong Keun

1997-01-01

Optimal motion for a robot manipulator is obtained by nonlinear programming. The objective of optimal motion is minimizing energy consumption of manipulator arm with fixed traveling time in the presence of obstacles. The geometric path is not predetermined. The total trajectory is described in terms of cubic B-spline polynomials and the coefficients of them are obtained to minimize a specific performance index. Obstacle avoidance is performed by the method that the square sum of penetration growth distances between every obstacles and robot links is included in the performance index with appropriate weighting coefficient. In all examples tested here, the solutions were converged to unique optimal trajectories from different initial ones. The optimal geometric path obtained in this research can be used in minimum time trajectory planning. (author)

An optimal control strategy for two-dimensional motion camouflage with non-holonimic constraints.

Science.gov (United States)

Rañó, Iñaki

2012-07-01

Motion camouflage is a stealth behaviour observed both in hover-flies and in dragonflies. Existing controllers for mimicking motion camouflage generate this behaviour on an empirical basis or without considering the kinematic motion restrictions present in animal trajectories. This study summarises our formal contributions to solve the generation of motion camouflage as a non-linear optimal control problem. The dynamics of the system capture the kinematic restrictions to motion of the agents, while the performance index ensures camouflage trajectories. An extensive set of simulations support the technique, and a novel analysis of the obtained trajectories contributes to our understanding of possible mechanisms to obtain sensor based motion camouflage, for instance, in mobile robots.

Design of an eye-in-hand sensing and servo control framework for harvesting robotics in dense vegetation

NARCIS (Netherlands)

Barth, Ruud; Hemming, Jochen; Henten, van E.J.

2016-01-01

A modular software framework design that allows flexible implementation of eye-in-hand sensing and motion control for agricultural robotics in dense vegetation is reported. Harvesting robots in cultivars with dense vegetation require multiple viewpoints and on-line trajectory adjustments in order

Stochastic receding horizon control: application to an octopedal robot

Science.gov (United States)

Shah, Shridhar K.; Tanner, Herbert G.

2013-06-01

Miniature autonomous systems are being developed under ARL's Micro Autonomous Systems and Technology (MAST). These systems can only be fitted with a small-size processor, and their motion behavior is inherently uncertain due to manufacturing and platform-ground interactions. One way to capture this uncertainty is through a stochastic model. This paper deals with stochastic motion control design and implementation for MAST- specific eight-legged miniature crawling robots, which have been kinematically modeled as systems exhibiting the behavior of a Dubin's car with stochastic noise. The control design takes the form of stochastic receding horizon control, and is implemented on a Gumstix Overo Fire COM with 720 MHz processor and 512 MB RAM, weighing 5.5 g. The experimental results show the effectiveness of this control law for miniature autonomous systems perturbed by stochastic noise.

Prototype of Remote Controlled Robot Vehicle to Scan Radioactive Contaminated Areas

International Nuclear Information System (INIS)

Ratongasoandrazana, J.B.; Raoelina Andriambololona; Rambolamanana, G.; Andrianiaina, H.; Rajaobelison, J.

2016-01-01

The ionizing radiations are not directly audible by the organs of sense of the human being. Maintenance and handling of sources of such ionizing radiations present some risks of very serious and often irreversible accident for human organism. The works of experimentation and maintenance in such zone also present the risks requiring some minimum of precaution. Thus, the main objective of this work is to design and develop (hard- and software) a prototype of educational semi-autonomous Radio Frequency controlled robot-vehicle based on 8-bit AVR-RISC Flash microcontroller system (ATmega128L) able to detect, identify and map the radioactive contaminated area. An integrated video camera coupled with a UHF video transmitter module, placed in front of the robot, will be used as visual feedback control to well direct it toward a precise place to reach. The navigation information and the data collected are transmitted from the robot toward the Computer via 02 Radio Frequency Transceivers for peer-to-peer serial data transfer in half-duplex mode. A Joystick module which is connected to the Computer parallel port allows full motion control of the platform. Robot-vehicle user interface program for the PC has been designed to allow full control of all functions of the robot vehicles.

Measurement of the robot motor capability of a robot motor system: a Fitts's-law-inspired approach.

Science.gov (United States)

Lin, Hsien-I; Lee, C S George

2013-07-02

Robot motor capability is a crucial factor for a robot, because it affects how accurately and rapidly a robot can perform a motion to accomplish a task constrained by spatial and temporal conditions. In this paper, we propose and derive a pseudo-index of motor performance (pIp) to characterize robot motor capability with robot kinematics, dynamics and control taken into consideration. The proposed pIp provides a quantitative measure for a robot with revolute joints, which is inspired from an index of performance in Fitts's law of human skills. Computer simulations and experiments on a PUMA 560 industrial robot were conducted to validate the proposed pIp for performing a motion accurately and rapidly.

CONTROL PREDICTIVO DE UN ROBOT TIPO SCARA PREDICTIVE CONTROL OF A SCARA ROBOT

Directory of Open Access Journals (Sweden)

Oscar Andrés Vivas Albán

2006-08-01

Full Text Available Este artículo presenta una aplicación eficiente de un control por modelo de referencia sobre un robot de tipo SCARA. El control estudiado es un control predictivo funcional, el que hace uso de un modelo dinámico simplificado del robot. Los ensayos simulados se realizan sobre un robot de cuatro grados de libertad, tipo SCARA. Con el fin de comparar diferentes estrategias de control, se diseña un controlador clásico tipo PID y dos controladores basados en el modelo de referencia. En este último caso el sistema se linealiza y se desacoplada por realimentación, lo que transforma el sistema a controlar en un simple par de integradores. Al sistema lineal y desacoplado resultante se le aplica el control por par calculado y el control predictivo funcional. Los tres controladores estudiados se simulan sobre el robot SCARA con valores numéricos reales. Las pruebas permiten valorar las respuestas de estos controladores en seguimiento de trayectoria, rechazo de perturbaciones y presencia de errores en el modelado con consignas complejas similares a las utilizadas en procesos de fabricación.This paper describes an efficient approach for model based control, applied on a SCARA robot. The studied control is the predictive functional control which uses a simplified dynamical model of the robot. The simulated tests are made on a SCARA type robot, with four DOF. To compare several control strategies, a classical PID control and two model based controllers are designed. In the last case, the model is first linearized and decoupled by feedback, transforming the system into a double set of integrators. Computed torque control and predictive functional control are applied to the linear and decoupled system. The three studied controllers are simulated on the SCARA robot with real numerical values. Tracking performance, disturbance rejection and model robot mismatch are enlightened, using complex machining tasks trajectories and error presence in the modelling

Design and control of MR haptic master/slave robot system for minimally invasive surgery

Science.gov (United States)

Uhm, Chang-Ho; Nguyen, Phoung Bac; Choi, Seung-Bok

2013-04-01

In this work, magnetorheological (MR) haptic master and slave robot for minimally invasive surgery (MIS) have been designed and tested. The proposed haptic master consists of four actuators; three MR brakes featuring gimbal structure for 3-DOF rotation motion(X, Y and Z axes) and one MR linear actuator for 1-DOF translational motion. The proposed slave robot which is connected with the haptic master has vertically multi- joints, and it consists of four DC servomotors; three for positioning endoscope and one for spinning motion. We added a fixed bar with a ball joint on the base of the slave for the endoscope position at the patient's abdomen to maintain safety. A gimbal structure at the end of the slave robotic arm for the last joint rotates freely with respect to the pivot point of the fixed bar. This master-slave system runs as if a teleoperation system through TCP/IP connection, programmed by LabVIEW. In order to achieve the desired position trajectory, a proportional-integral-derivative (PID) controller is designed and implemented. It has been demonstrated that the effective tracking control performances for the desired motion are well achieved and presented in time domain. At last, an experiment in virtual environments is undertaken to investigate the effectiveness of the MR haptic master device for MIS system.

Trajectory of coronary motion and its significance in robotic motion cancellation.

Science.gov (United States)

Cattin, Philippe; Dave, Hitendu; Grünenfelder, Jürg; Szekely, Gabor; Turina, Marko; Zünd, Gregor

2004-05-01

To characterize remaining coronary artery motion of beating pig hearts after stabilization with an 'Octopus' using an optical remote analysis technique. Three pigs (40, 60 and 65 kg) underwent full sternotomy after receiving general anesthesia. An 8-bit high speed black and white video camera (50 frames/s) coupled with a laser sensor (60 microm resolution) were used to capture heart wall motion in all three dimensions. Dopamine infusion was used to deliberately modulate cardiac contractility. Synchronized ECG, blood pressure, airway pressure and video data of the region around the first branching point of the left anterior descending (LAD) coronary artery after Octopus stabilization were captured for stretches of 8 s each. Several sequences of the same region were captured over a period of several minutes. Computerized off-line analysis allowed us to perform minute characterization of the heart wall motion. The movement of the points of interest on the LAD ranged from 0.22 to 0.81 mm in the lateral plane (x/y-axis) and 0.5-2.6 mm out of the plane (z-axis). Fast excursions (>50 microm/s in the lateral plane) occurred corresponding to the QRS complex and the T wave; while slow excursion phases (movement of the coronary artery after stabilization appears to be still significant. Minute characterization of the trajectory of motion could provide the substrate for achieving motion cancellation for existing robotic systems. Velocity plots could also help improve gated cardiac imaging.

Structured Kernel Subspace Learning for Autonomous Robot Navigation.

Science.gov (United States)

Kim, Eunwoo; Choi, Sungjoon; Oh, Songhwai

2018-02-14

This paper considers two important problems for autonomous robot navigation in a dynamic environment, where the goal is to predict pedestrian motion and control a robot with the prediction for safe navigation. While there are several methods for predicting the motion of a pedestrian and controlling a robot to avoid incoming pedestrians, it is still difficult to safely navigate in a dynamic environment due to challenges, such as the varying quality and complexity of training data with unwanted noises. This paper addresses these challenges simultaneously by proposing a robust kernel subspace learning algorithm based on the recent advances in nuclear-norm and l 1 -norm minimization. We model the motion of a pedestrian and the robot controller using Gaussian processes. The proposed method efficiently approximates a kernel matrix used in Gaussian process regression by learning low-rank structured matrix (with symmetric positive semi-definiteness) to find an orthogonal basis, which eliminates the effects of erroneous and inconsistent data. Based on structured kernel subspace learning, we propose a robust motion model and motion controller for safe navigation in dynamic environments. We evaluate the proposed robust kernel learning in various tasks, including regression, motion prediction, and motion control problems, and demonstrate that the proposed learning-based systems are robust against outliers and outperform existing regression and navigation methods.

Robotic motion compensation for applications in radiation oncology

Energy Technology Data Exchange (ETDEWEB)

Herrmann, Christian

2013-07-22

Radiation therapy today, on account of improvements in treatment procedures over the last 60 years, allows precise treatment of static tumors inside the human body. However, irradiation of moving tumors is still a challenging task as moving tumors often leave the treatment beam and the radiation dose delivered to the tumor reduces simultaneously increasing that on healthy tissue. This research work aims to push the frontiers of radiation therapy in order to enable precise treatment of moving tumors with focus on research and development of a unique real-time system enabling active motion compensation through robotic means to compensate tumor motion. During treatment, patients lie on a treatment couch which is normally used for static position corrections of patient set-up errors prior to radiation treatment. The treatment couch used, called HexaPOD, is a parallel manipulator with six degrees of freedom which can precisely position heavy loads inside a small region. Despite the HexaPOD not initially built with dynamics in mind, it is used in this work for sustained motion compensation by moving patients such that tumors stay precisely located at the center of the treatment beam during the complete course of treatment. In order to realize real-time tumor motion compensation by means of the HexaPOD, several challenges need to be addressed. Real-time aspects are covered by the adoption of a hard real-time operation system in combination with measurement and estimation of latencies of all physical quantities in the compensation system such as tumor or breathing position measurements. Accurate timing information is respected consistently in the whole system and all software-induced latencies are adaptively compensated for. This requires knowledge of future tumor positions from predictors. Several predictors for breathing and tumor motion predictions are proposed and evaluated in terms of a variety of different performance metrics. Extensions to prediction algorithms are

Robotic motion compensation for applications in radiation oncology

International Nuclear Information System (INIS)

Herrmann, Christian

2013-01-01

Radiation therapy today, on account of improvements in treatment procedures over the last 60 years, allows precise treatment of static tumors inside the human body. However, irradiation of moving tumors is still a challenging task as moving tumors often leave the treatment beam and the radiation dose delivered to the tumor reduces simultaneously increasing that on healthy tissue. This research work aims to push the frontiers of radiation therapy in order to enable precise treatment of moving tumors with focus on research and development of a unique real-time system enabling active motion compensation through robotic means to compensate tumor motion. During treatment, patients lie on a treatment couch which is normally used for static position corrections of patient set-up errors prior to radiation treatment. The treatment couch used, called HexaPOD, is a parallel manipulator with six degrees of freedom which can precisely position heavy loads inside a small region. Despite the HexaPOD not initially built with dynamics in mind, it is used in this work for sustained motion compensation by moving patients such that tumors stay precisely located at the center of the treatment beam during the complete course of treatment. In order to realize real-time tumor motion compensation by means of the HexaPOD, several challenges need to be addressed. Real-time aspects are covered by the adoption of a hard real-time operation system in combination with measurement and estimation of latencies of all physical quantities in the compensation system such as tumor or breathing position measurements. Accurate timing information is respected consistently in the whole system and all software-induced latencies are adaptively compensated for. This requires knowledge of future tumor positions from predictors. Several predictors for breathing and tumor motion predictions are proposed and evaluated in terms of a variety of different performance metrics. Extensions to prediction algorithms are

Compact teleoperated laparoendoscopic single-site robotic surgical system: Kinematics, control, and operation.

Science.gov (United States)

Isaac-Lowry, Oran Jacob; Okamoto, Steele; Pedram, Sahba Aghajani; Woo, Russell; Berkelman, Peter

2017-12-01

To date a variety of teleoperated surgical robotic systems have been developed to improve a surgeon's ability to perform demanding single-port procedures. However typical large systems are bulky, expensive, and afford limited angular motion, while smaller designs suffer complications arising from limited motion range, speed, and force generation. This work was to develop and validate a simple, compact, low cost single site teleoperated laparoendoscopic surgical robotic system, with demonstrated capability to carry out basic surgical procedures. This system builds upon previous work done at the University of Hawaii at Manoa and includes instrument and endoscope manipulators as well as compact articulated instruments designed to overcome single incision geometry complications. A robotic endoscope holder was used for the base, with an added support frame for teleoperated manipulators and instruments fabricated mostly from 3D printed parts. Kinematics and control methods were formulated for the novel manipulator configuration. Trajectory following results from an optical motion tracker and sample task performance results are presented. Results indicate that the system has successfully met the goal of basic surgical functionality while minimizing physical size, complexity, and cost. Copyright © 2017 John Wiley & Sons, Ltd.

Rudder Based Roll Control via host-computer of A Robotic Boat

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Xinping Bao

2009-03-01

Full Text Available Rudder based roll control of a small-sized robotic boat is a key technique for the devices on board to achieve good performance. This paper introduces a host-based robotic boat capable of performing basic movement operations. The course keeping and roll reduction are studied via rudder based method in simulations and sea trials. The boat dynamic model is built with the combination of mathematical analysis and system identification technique. A mixed sensitivity H control method design is selected since yaw and roll motion are posed in different frequency domains. Computer simulations and experiments carried out show that successful results are achieved.

Rudder Based Roll Control via Host-Computer of a Robotic Boat

Directory of Open Access Journals (Sweden)

Xinping Bao

2009-03-01

Full Text Available Rudder based roll control of a small-sized robotic boat is a key technique for the devices on board to achieve good performance. This paper introduces a host-based robotic boat capable of performing basic movement operations. The course keeping and roll reduction are studied via rudder based method in simulations and sea trials. The boat dynamic model is built with the combination of mathematical analysis and system identification technique. A mixed sensitivity H∞ control method design is selected since yaw and roll motion are posed in different frequency domains. Computer simulations and experiments carried out show that successful results are achieved.

D2 Delta Robot Structural Design and Kinematics Analysis

Science.gov (United States)

Yang, Xudong; wang, Song; Dong, Yu; Yang, Hai

2017-12-01

In this paper, a new type of Delta robot with only two degrees of freedom is proposed on the basis of multi - degree - of - freedom delta robot. In order to meet our application requirements, we have carried out structural design and analysis of the robot. Through SolidWorks modeling, combined with 3D printing technology to determine the final robot structure. In order to achieve the precise control of the robot, the kinematics analysis of the robot was carried out. The SimMechanics toolbox of MATLAB is used to establish the mechanism model, and the kinematics mathematical model is used to simulate the robot motion control in Matlab environment. Finally, according to the design mechanism, the working space of the robot is drawn by the graphic method, which lays the foundation for the motion control of the subsequent robot.

Design and implementation of self-balancing coaxial two wheel robot based on HSIC

Science.gov (United States)

Hu, Tianlian; Zhang, Hua; Dai, Xin; Xia, Xianfeng; Liu, Ran; Qiu, Bo

2007-12-01

This thesis has studied the control problem concerning position and orientation control of self-balancing coaxial two wheel robot based on the human simulated intelligent control (HSIC) theory. Adopting Lagrange equation, the dynamic model of self-balancing coaxial two-wheel Robot is built up, and the Sensory-motor Intelligent Schemas (SMIS) of HSIC controller for the robot is designed by analyzing its movement and simulating the human controller. In robot's motion process, by perceiving position and orientation of the robot and using multi-mode control strategy based on characteristic identification, the HSIC controller enables the robot to control posture. Utilizing Matlab/Simulink, a simulation platform is established and a motion controller is designed and realized based on RT-Linux real-time operating system, employing high speed ARM9 processor S3C2440 as kernel of the motion controller. The effectiveness of the new design is testified by the experiment.

Adaptive Robot to Person Encounter by Motion Patterns

DEFF Research Database (Denmark)

Andersen, Hans Jørgen; Bak, Thomas; Svenstrup, Mikael

2009-01-01

This paper introduces a new method for adaptive control of a robot approaching a person controlled by the person's interest in interaction. For adjustment of the robot behavior a cost function centered in the person is adapted according to an introduced person evaluator method relying on the three...... variables: the distance between the person and the robot, the relative velocity between the two, and position of the person. The person evaluator method determine the person's interest by evaluating the spatial relationship between robot and person in a Case Based Reasoning (CBR) system that is trained...... to determine to which degree the person is interested in interaction. The outcome of the CBR system is used to adapt the cost function around the person, so that the robot's behavior is adapted to the expressed interest. The proposed methods are evaluated by a number of physical experiments that demonstrate...

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

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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.

Robot Control Overview: An Industrial Perspective

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T. Brogårdh

2009-07-01

Full Text Available One key competence for robot manufacturers is robot control, defined as all the technologies needed to control the electromechanical system of an industrial robot. By means of modeling, identification, optimization, and model-based control it is possible to reduce robot cost, increase robot performance, and solve requirements from new automation concepts and new application processes. Model-based control, including kinematics error compensation, optimal servo reference- and feed-forward generation, and servo design, tuning, and scheduling, has meant a breakthrough for the use of robots in industry. Relying on this breakthrough, new automation concepts such as high performance multi robot collaboration and human robot collaboration can be introduced. Robot manufacturers can build robots with more compliant components and mechanical structures without loosing performance and robots can be used also in applications with very high performance requirements, e.g., in assembly, machining, and laser cutting. In the future it is expected that the importance of sensor control will increase, both with respect to sensors in the robot structure to increase the control performance of the robot itself and sensors outside the robot related to the applications and the automation systems. In this connection sensor fusion and learning functionalities will be needed together with the robot control for easy and intuitive installation, programming, and maintenance of industrial robots.

Measurement of the Robot Motor Capability of a Robot Motor System: A Fitts’s-Law-Inspired Approach

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C. S. George Lee

2013-07-01

Full Text Available Robot motor capability is a crucial factor for a robot, because it affects how accurately and rapidly a robot can perform a motion to accomplish a task constrained by spatial and temporal conditions. In this paper, we propose and derive a pseudo-index of motor performance (pIp to characterize robot motor capability with robot kinematics, dynamics and control taken into consideration. The proposed pIp provides a quantitative measure for a robot with revolute joints, which is inspired from an index of performance in Fitts’s law of human skills. Computer simulations and experiments on a PUMA 560 industrial robot were conducted to validate the proposed pIp for performing a motion accurately and rapidly.

A robot and control algorithm that can synchronously assist in naturalistic motion during body-weight-supported gait training following neurologic injury.

Science.gov (United States)

Aoyagi, Daisuke; Ichinose, Wade E; Harkema, Susan J; Reinkensmeyer, David J; Bobrow, James E

2007-09-01

Locomotor training using body weight support on a treadmill and manual assistance is a promising rehabilitation technique following neurological injuries, such as spinal cord injury (SCI) and stroke. Previous robots that automate this technique impose constraints on naturalistic walking due to their kinematic structure, and are typically operated in a stiff mode, limiting the ability of the patient or human trainer to influence the stepping pattern. We developed a pneumatic gait training robot that allows for a full range of natural motion of the legs and pelvis during treadmill walking, and provides compliant assistance. However, we observed an unexpected consequence of the device's compliance: unimpaired and SCI individuals invariably began walking out-of-phase with the device. Thus, the robot perturbed rather than assisted stepping. To address this problem, we developed a novel algorithm that synchronizes the device in real-time to the actual motion of the individual by sensing the state error and adjusting the replay timing to reduce this error. This paper describes data from experiments with individuals with SCI that demonstrate the effectiveness of the synchronization algorithm, and the potential of the device for relieving the trainers of strenuous work while maintaining naturalistic stepping.

Design of Optimal Hybrid Position/Force Controller for a Robot Manipulator Using Neural Networks

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Vikas Panwar

2007-01-01

Full Text Available The application of quadratic optimization and sliding-mode approach is considered for hybrid position and force control of a robot manipulator. The dynamic model of the manipulator is transformed into a state-space model to contain two sets of state variables, where one describes the constrained motion and the other describes the unconstrained motion. The optimal feedback control law is derived solving matrix differential Riccati equation, which is obtained using Hamilton Jacobi Bellman optimization. The optimal feedback control law is shown to be globally exponentially stable using Lyapunov function approach. The dynamic model uncertainties are compensated with a feedforward neural network. The neural network requires no preliminary offline training and is trained with online weight tuning algorithms that guarantee small errors and bounded control signals. The application of the derived control law is demonstrated through simulation with a 4-DOF robot manipulator to track an elliptical planar constrained surface while applying the desired force on the surface.

A Motion Planning Method for Omnidirectional Mobile Robot Based on the Anisotropic Characteristics

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Chuntao Leng

2008-11-01

Full Text Available A more suitable motion planning method for an omni-directional mobile robot (OMR, an improved APF method (iAPF, is proposed in this paper by introducing the revolving factor into the artificial potential field (APF. Accordingly, the motion direction derived from traditional artificial potential field (tAPF is regulated. The maximum velocity, maximum acceleration and energy consumption of the OMR moving in different directions are analyzed, based on the kinematic and dynamic constraints of an OMR, and the anisotropy of OMR is presented in this paper. Then the novel concept of an Anisotropic-Function is proposed to indicate the quality of motion in different directions, which can make a very favorable trade-off between time-optimality, stability and efficacy-optimality. In order to obtain the optimal motion, the path that the robot can take in order to avoid the obstacle safely and reach the goal in a shorter path is deduced. Finally, simulations and experiments are carried out to demonstrate that the motion resulting from the iAPF is high-speed, highly stable and highly efficient when compared to the tAPF.

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

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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.

Human Hand Motion Analysis and Synthesis of Optimal Power Grasps for a Robotic Hand

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Francesca Cordella

2014-03-01

Full Text Available Biologically inspired robotic systems can find important applications in biomedical robotics, since studying and replicating human behaviour can provide new insights into motor recovery, functional substitution and human-robot interaction. The analysis of human hand motion is essential for collecting information about human hand movements useful for generalizing reaching and grasping actions on a robotic system. This paper focuses on the definition and extraction of quantitative indicators for describing optimal hand grasping postures and replicating them on an anthropomorphic robotic hand. A motion analysis has been carried out on six healthy human subjects performing a transverse volar grasp. The extracted indicators point to invariant grasping behaviours between the involved subjects, thus providing some constraints for identifying the optimal grasping configuration. Hence, an optimization algorithm based on the Nelder-Mead simplex method has been developed for determining the optimal grasp configuration of a robotic hand, grounded on the aforementioned constraints. It is characterized by a reduced computational cost. The grasp stability has been tested by introducing a quality index that satisfies the form-closure property. The grasping strategy has been validated by means of simulation tests and experimental trials on an arm-hand robotic system. The obtained results have shown the effectiveness of the extracted indicators to reduce the non-linear optimization problem complexity and lead to the synthesis of a grasping posture able to replicate the human behaviour while ensuring grasp stability. The experimental results have also highlighted the limitations of the adopted robotic platform (mainly due to the mechanical structure to achieve the optimal grasp configuration.

Teleautonomous Control on Rescue Robot Prototype

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Son Kuswadi

2012-12-01

Full Text Available Robot application in disaster area can help responder team to save victims. In order to finish task, robot must have flexible movement mechanism so it can pass through uncluttered area. Passive linkage can be used on robot chassis so it can give robot flexibility. On physical experiments, robot is succeeded to move through gravels and 5 cm obstacle. Rescue robot also has specialized control needs. Robot must able to be controlled remotely. It also must have ability to move autonomously. Teleautonomous control method is combination between those methods. It can be concluded from experiments that on teleoperation mode, operator must get used to see environment through robot’s camera. While on autonomous mode, robot is succeeded to avoid obstacle and search target based on sensor reading and controller program. On teleautonomous mode, robot can change control mode by using bluetooth communication for data transfer, so robot control will be more flexible.

Development of safe mechanism for surgical robots using equilibrium point control method.

Science.gov (United States)

Park, Shinsuk; Lim, Hokjin; Kim, Byeong-sang; Song, Jae-bok

2006-01-01

This paper introduces a novel mechanism for surgical robotic systems to generate human arm-like compliant motion. The mechanism is based on the idea of the equilibrium point control hypothesis which claims that multi-joint limb movements are achieved by shifting the limbs' equilibrium positions defined by neuromuscular activity. The equilibrium point control can be implemented on a robot manipulator by installing two actuators at each joint of the manipulator, one to control the joint position, and the other to control the joint stiffness. This double-actuator mechanism allows us to arbitrarily manipulate the stiffness (or impedance) of a robotic manipulator as well as its position. Also, the force at the end-effector can be estimated based on joint stiffness and joint angle changes without using force transducers. A two-link manipulator and a three-link manipulator with the double-actuator units have been developed, and experiments and simulation results show the potential of the proposed approach. By creating the human arm-like behavior, this mechanism can improve the performance of robot manipulators to execute stable and safe movement in surgical environments by using a simple control scheme.

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

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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.

Experiments in teleoperator and autonomous control of space robotic vehicles

Science.gov (United States)

Alexander, Harold L.

1991-01-01

A program of research embracing teleoperator and automatic navigational control of freely flying satellite robots is presented. Current research goals include: (1) developing visual operator interfaces for improved vehicle teleoperation; (2) determining the effects of different visual interface system designs on operator performance; and (3) achieving autonomous vision-based vehicle navigation and control. This research program combines virtual-environment teleoperation studies and neutral-buoyancy experiments using a space-robot simulator vehicle currently under development. Visual-interface design options under investigation include monoscopic versus stereoscopic displays and cameras, helmet-mounted versus panel-mounted display monitors, head-tracking versus fixed or manually steerable remote cameras, and the provision of vehicle-fixed visual cues, or markers, in the remote scene for improved sensing of vehicle position, orientation, and motion.

An Augmented Discrete-Time Approach for Human-Robot Collaboration

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Peidong Liang

2016-01-01

Full Text Available Human-robot collaboration (HRC is a key feature to distinguish the new generation of robots from conventional robots. Relevant HRC topics have been extensively investigated recently in academic institutes and companies to improve human and robot interactive performance. Generally, human motor control regulates human motion adaptively to the external environment with safety, compliance, stability, and efficiency. Inspired by this, we propose an augmented approach to make a robot understand human motion behaviors based on human kinematics and human postural impedance adaptation. Human kinematics is identified by geometry kinematics approach to map human arm configuration as well as stiffness index controlled by hand gesture to anthropomorphic arm. While human arm postural stiffness is estimated and calibrated within robot empirical stability region, human motion is captured by employing a geometry vector approach based on Kinect. A biomimetic controller in discrete-time is employed to make Baxter robot arm imitate human arm behaviors based on Baxter robot dynamics. An object moving task is implemented to validate the performance of proposed methods based on Baxter robot simulator. Results show that the proposed approach to HRC is intuitive, stable, efficient, and compliant, which may have various applications in human-robot collaboration scenarios.

Analysis of the accuracy and robustness of the leap motion controller.

Science.gov (United States)

Weichert, Frank; Bachmann, Daniel; Rudak, Bartholomäus; Fisseler, Denis

2013-05-14

The Leap Motion Controller is a new device for hand gesture controlled user interfaces with declared sub-millimeter accuracy. However, up to this point its capabilities in real environments have not been analyzed. Therefore, this paper presents a first study of a Leap Motion Controller. The main focus of attention is on the evaluation of the accuracy and repeatability. For an appropriate evaluation, a novel experimental setup was developed making use of an industrial robot with a reference pen allowing a position accuracy of 0.2 mm. Thereby, a deviation between a desired 3D position and the average measured positions below 0.2 mm has been obtained for static setups and of 1.2 mm for dynamic setups. Using the conclusion of this analysis can improve the development of applications for the Leap Motion controller in the field of Human-Computer Interaction.

INTEGRATED ROBOT-HUMAN CONTROL IN MINING OPERATIONS

Energy Technology Data Exchange (ETDEWEB)

George Danko

2005-04-01

This report contains a detailed description of the work conducted in the first year of the project on Integrated Robot-Human Control in Mining Operations at University of Nevada, Reno. This project combines human operator control with robotic control concepts to create a hybrid control architecture, in which the strengths of each control method are combined to increase machine efficiency and reduce operator fatigue. The kinematics reconfiguration type differential control of the excavator implemented with a variety of ''software machine kinematics'' is the key feature of the project. This software re-configured excavator is more desirable to execute a given digging task. The human operator retains the master control of the main motion parameters, while the computer coordinates the repetitive movement patterns of the machine links. These repetitive movements may be selected from a pre-defined family of trajectories with different transformations. The operator can make adjustments to this pattern in real time, as needed, to accommodate rapidly-changing environmental conditions. A Bobcat{reg_sign} 435 excavator was retrofitted with electro-hydraulic control valve elements. The modular electronic control was tested and the basic valve characteristics were measured for each valve at the Robotics Laboratory at UNR. Position sensors were added to the individual joint control actuators, and the sensors were calibrated. An electronic central control system consisting of a portable computer, converters and electronic driver components was interfaced to the electro-hydraulic valves and position sensors. The machine is operational with or without the computer control system depending on whether the computer interface is on or off. In preparation for emulated mining tasks tests, typical, repetitive tool trajectories during surface mining operations were recorded at the Newmont Mining Corporation's ''Lone Tree'' mine in Nevada.

Hydrodynamics of a robotic fish tail: effects of the caudal peduncle, fin ray motions and the flow speed.

Science.gov (United States)

Ren, Ziyu; Yang, Xingbang; Wang, Tianmiao; Wen, Li

2016-02-08

Recent advances in understanding fish locomotion with robotic devices have included the use of biomimetic flapping based and fin undulatory locomotion based robots, treating two locomotions separately from each other. However, in most fish species, patterns of active movements of fins occur in concert with the body undulatory deformation during swimming. In this paper, we describe a biomimetic robotic caudal fin programmed with individually actuated fin rays to mimic the fin motion of the Bluegill Sunfish (Lepomis macrochirus) and coupled with heave and pitch oscillatory motions adding to the robot to mimic the peduncle motion which is derived from the undulatory fish body. Multiple-axis force and digital particle image velocimetry (DPIV) experiments from both the vertical and horizontal planes behind the robotic model were conducted under different motion programs and flow speeds. We found that both mean thrust and lift could be altered by changing the phase difference (φ) from 0° to 360° between the robotic caudal peduncle and the fin ray motion (spanning from 3 mN to 124 mN). Notably, DPIV results demonstrated that the caudal fin generated multiple wake flow patterns in both the vertical and horizontal planes by varying φ. Vortex jet angle and thrust impulse also varied significantly both in these two planes. In addition, the vortex shedding position along the spanwise tail direction could be shifted around the mid-sagittal position between the upper and lower lobes by changing the phase difference. We hypothesize that the fish caudal fin may serve as a flexible vectoring propeller during swimming and may be critical for the high maneuverability of fish.

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...

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

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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.

Space robot simulator vehicle

Science.gov (United States)

Cannon, R. H., Jr.; Alexander, H.

1985-01-01

A Space Robot Simulator Vehicle (SRSV) was constructed to model a free-flying robot capable of doing construction, manipulation and repair work in space. The SRSV is intended as a test bed for development of dynamic and static control methods for space robots. The vehicle is built around a two-foot-diameter air-cushion vehicle that carries batteries, power supplies, gas tanks, computer, reaction jets and radio equipment. It is fitted with one or two two-link manipulators, which may be of many possible designs, including flexible-link versions. Both the vehicle body and its first arm are nearly complete. Inverse dynamic control of the robot's manipulator has been successfully simulated using equations generated by the dynamic simulation package SDEXACT. In this mode, the position of the manipulator tip is controlled not by fixing the vehicle base through thruster operation, but by controlling the manipulator joint torques to achieve the desired tip motion, while allowing for the free motion of the vehicle base. One of the primary goals is to minimize use of the thrusters in favor of intelligent control of the manipulator. Ways to reduce the computational burden of control are described.

Decentralized coverage control problems for mobile robotic sensor and actuator networks

CERN Document Server

Savkin, A; Xi, Z; Javed, F; Matveev, A; Nguyen, H

2015-01-01

This book introduces various coverage control problems for mobile sensor networks including barrier, sweep and blanket. Unlike many existing algorithms, all of the robotic sensor and actuator motion algorithms developed in the book are fully decentralized or distributed, computationally efficient, easily implementable in engineering practice and based only on information on the closest neighbours of each mobile sensor and actuator and local information about the environment. Moreover, the mobile robotic sensors have no prior information about the environment in which they operation. These various types of coverage problems have never been covered before by a single book in a systematic way. Another topic of this book is the study of mobile robotic sensor and actuator networks. Many modern engineering applications include the use of sensor and actuator networks to provide efficient and effective monitoring and control of industrial and environmental processes. Such mobile sensor and actuator networks are abl...

Position Control Method For Pick And Place Robot Arm For Object Sorting System

Directory of Open Access Journals (Sweden)

Khin Moe Myint

2015-08-01

Full Text Available The more increase the number of industries in developing countries the more require labourers or workers in that. To reduce the cost of labour force and to increase the manufacturing capacity of industries the advanced robot arms are more needed. The aim of this journal is to eliminate the manual control for object sorting system.Robot arm design in this research uses two joints three links and servo motors to drive. Microcontroller is used to generate required PWM signal for servo motors. In this research the position control of robot arm was designed by using kinematic control methods. There are two types of kinematic control methods which are forward and reverse kinematic methods. In forward kinematic method the input parameters are the joint angles and link length of robot arm and then the output is the position at XYZ coordinate of tool or gripper. In inverse kinematic the input parameters are position at XYZ coordinate of gripper and the link length of robot arm and then the output parameters are the joint angles. So kinematic methods can explain the analytical description of the geometry motion of the manipulator with reference to a robot coordinate system fixed to a frame without consideration of the forces or the moments causing the movements. For sorting system Metal detector is used to detect the metal or non-metal. This position control of pick and place robot arm is fully tested and the result is obtained more precisely.

Fiscal 2000 report on result of R and D on robot system cooperating and coexisting with human beings. R and D on robot system cooperating and coexisting with human beings; 2000 nendo ningen kyocho kyozongata robot system kenkyu kaihatsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-06-01

A highly safe and reliable robot is being developed capable of cooperating with human beings and executing complicated operations in a human working/living space. This paper describes the fiscal 2000 results. Development of robot motion library was continued for extended task for providing services to people in care houses for the aged controlling motions of the humanoid robot. A basic design for a personal service system by the humanoid robot was conducted with the aim of nursing assistance and for the objective of developing a portable terminal type tele-operation device. A public and a home cockpit were researched with the purpose of developing user interfaces for telexistence control. A dynamic simulator for humanoid robots was built, with motions of standing-up and walking examined, in order to develop basic theories for the dual-handed tasks aided by the leg-arm cooperative motion. To develop a robot that properly and safely cooperates and coexists with the human beings, it is essential to obtain a dynamically reasonable and natural control law, so that the basic studies were conducted in this direction. With the purpose of developing a motion capture and learning system, a virtual robot platform and an information acquiring interface were developed. Studies were also conducted on modeling technique for achieving realistic material properties from high-precision image synthesis and actual images. (NEDO)

Development of a force-reflecting robotic platform for cardiac catheter navigation.

Science.gov (United States)

Park, Jun Woo; Choi, Jaesoon; Pak, Hui-Nam; Song, Seung Joon; Lee, Jung Chan; Park, Yongdoo; Shin, Seung Min; Sun, Kyung

2010-11-01

Electrophysiological catheters are used for both diagnostics and clinical intervention. To facilitate more accurate and precise catheter navigation, robotic cardiac catheter navigation systems have been developed and commercialized. The authors have developed a novel force-reflecting robotic catheter navigation system. The system is a network-based master-slave configuration having a 3-degree of freedom robotic manipulator for operation with a conventional cardiac ablation catheter. The master manipulator implements a haptic user interface device with force feedback using a force or torque signal either measured with a sensor or estimated from the motor current signal in the slave manipulator. The slave manipulator is a robotic motion control platform on which the cardiac ablation catheter is mounted. The catheter motions-forward and backward movements, rolling, and catheter tip bending-are controlled by electromechanical actuators located in the slave manipulator. The control software runs on a real-time operating system-based workstation and implements the master/slave motion synchronization control of the robot system. The master/slave motion synchronization response was assessed with step, sinusoidal, and arbitrarily varying motion commands, and showed satisfactory performance with insignificant steady-state motion error. The current system successfully implemented the motion control function and will undergo safety and performance evaluation by means of animal experiments. Further studies on the force feedback control algorithm and on an active motion catheter with an embedded actuation mechanism are underway. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Integrated Robot-Human Control in Mining Operations

Energy Technology Data Exchange (ETDEWEB)

George Danko

2007-09-30

This report contains a detailed description of the work conducted for the project on Integrated Robot-Human Control in Mining Operations at University of Nevada, Reno. This project combines human operator control with robotic control concepts to create a hybrid control architecture, in which the strengths of each control method are combined to increase machine efficiency and reduce operator fatigue. The kinematics reconfiguration type differential control of the excavator implemented with a variety of 'software machine kinematics' is the key feature of the project. This software re-configured excavator is more desirable to execute a given digging task. The human operator retains the master control of the main motion parameters, while the computer coordinates the repetitive movement patterns of the machine links. These repetitive movements may be selected from a pre-defined family of trajectories with different transformations. The operator can make adjustments to this pattern in real time, as needed, to accommodate rapidly-changing environmental conditions. A working prototype has been developed using a Bobcat 435 excavator. The machine is operational with or without the computer control system depending on whether the computer interface is on or off. In preparation for emulated mining tasks tests, typical, repetitive tool trajectories during surface mining operations were recorded at the Newmont Mining Corporation's 'Lone Tree' mine in Nevada. Analysis of these working trajectories has been completed. The motion patterns, when transformed into a family of curves, may serve as the basis for software-controlled machine kinematics transformation in the new human-robot control system. A Cartesian control example has been developed and tested both in simulation and on the experimental excavator. Open-loop control is robustly stable and free of short-term dynamic problems, but it allows for drifting away from the desired motion kinematics of the

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.

A study on autonomous maintenance robot, 7

International Nuclear Information System (INIS)

Fukuda, Toshio; Hosokai, Hidemi; Shimasaka, Naoki; Kaneshige, Masanori; Iwasaki, Shinnosuke.

1990-01-01

This paper deals with the new mechanism of a new maintenance robot, Mark IV, following the previous reports on pipeline inspection and maintenance robots of Mark I, II, and III. The Mark IV has a mechanism capable of inspecting surfaces of storage tanks as well as pipeline outer surfaces, which is another capability of the maintenance robots, different from the previous ones. The main features of Mark IV are as follows, (i) The robot has a multijoint structure, so that it has better adaptability to the curvartures of pipelines and storage tanks. (ii) The joint of the robot has SMA actuators to make the robot lighter in weight. Some actuator shape characteristics are also examined for the robot structure and control. (iii) The robot has suckers at both ends so that the robot can climb up along the wall from the ground. (iv) A robot with the inch worm mechanisms has many functional motions, such that it can pass over flanges and T-joints, and transfer to adjacent pipelines with a wider range of pipe diameters. (v) A control method is given for the mobile motion control. Thus, the functional level of the maintenance robot has been greatly improved by the introduction of the Mark IV robot. (author)

Anthropomorphic Robot Hand And Teaching Glove

Science.gov (United States)

Engler, Charles D., Jr.

1991-01-01

Robotic forearm-and-hand assembly manipulates objects by performing wrist and hand motions with nearly human grasping ability and dexterity. Imitates hand motions of human operator who controls robot in real time by programming via exoskeletal "teaching glove". Telemanipulator systems based on this robotic-hand concept useful where humanlike dexterity required. Underwater, high-radiation, vacuum, hot, cold, toxic, or inhospitable environments potential application sites. Particularly suited to assisting astronauts on space station in safely executing unexpected tasks requiring greater dexterity than standard gripper.

Transferring human impedance regulation skills to robots

CERN Document Server

Ajoudani, Arash

2016-01-01

This book introduces novel thinking and techniques to the control of robotic manipulation. In particular, the concept of teleimpedance control as an alternative method to bilateral force-reflecting teleoperation control for robotic manipulation is introduced. In teleimpedance control, a compound reference command is sent to the slave robot including both the desired motion trajectory and impedance profile, which are then realized by the remote controller. This concept forms a basis for the development of the controllers for a robotic arm, a dual-arm setup, a synergy-driven robotic hand, and a compliant exoskeleton for improved interaction performance.

Robotic Motion Learning Framework to Promote Social Engagement

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Rachael Burns

2018-02-01

Full Text Available Imitation is a powerful component of communication between people, and it poses an important implication in improving the quality of interaction in the field of human–robot interaction (HRI. This paper discusses a novel framework designed to improve human–robot interaction through robotic imitation of a participant’s gestures. In our experiment, a humanoid robotic agent socializes with and plays games with a participant. For the experimental group, the robot additionally imitates one of the participant’s novel gestures during a play session. We hypothesize that the robot’s use of imitation will increase the participant’s openness towards engaging with the robot. Experimental results from a user study of 12 subjects show that post-imitation, experimental subjects displayed a more positive emotional state, had higher instances of mood contagion towards the robot, and interpreted the robot to have a higher level of autonomy than their control group counterparts did. These results point to an increased participant interest in engagement fueled by personalized imitation during interaction.

Towards Behavior Control for Evolutionary Robot Based on RL with ENN

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Jingan Yang

2012-03-01

Full Text Available This paper proposes a behavior-switching control strategy of anevolutionary robotics based on Artificial NeuralNetwork (ANN and Genetic Algorithms (GA. This method is able not only to construct thereinforcement learning models for autonomous robots and evolutionary robot modules thatcontrol behaviors and reinforcement learning environments, and but also to perform thebehavior-switching control and obstacle avoidance of an evolutionary robotics (ER intime-varying environments with static and moving obstacles by combining ANN and GA.The experimental results on thebasic behaviors and behavior-switching control have demonstrated that ourmethod can perform the decision-making strategy and parameters set opimization ofFNN and GA by learning and can escape successfully from the trap of a localminima and avoid \\emph{"motion deadlock" status} of humanoid soccer robotics agents,and reduce the oscillation of the planned trajectory betweenthe multiple obstacles by crossover and mutation. Some results of the proposed algorithmhave been successfully applied to our simulation humanoid robotics soccer team CIT3Dwhich won \\emph{the 1st prize} of RoboCup Championship and ChinaOpen2010 (July 2010 and \\emph{the $2^{nd}$ place}of the official RoboCup World Championship on 5-11 July, 2011 in Istanbul, Turkey.As compared with the conventional behavior network and the adaptive behavior method,the genetic encoding complexity of our algorithm is simplified, and the networkperformance and the {\\em convergence rate $\\rho$} have been greatlyimproved.

Reduced Attitude Control of a Robotic Underwater Vehicle

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Bláha Lukáš

2017-01-01

Full Text Available This paper deals with stabilization and reduced attitude control of a robotic underwater vehicle. The vehicle is assumed to be able to perform a full stable rotations around all axes in underwater space, that is why the standard bottom-heavy structure is not used. The system preferably uses a vectored-thrust arrangement and is built as an overactuated system, which enables to gain a better robustness and guarantees a stable controlled motion even if some thruster suddenly stop working. Because the heading angle cannot be measured, the reduced attitude control strategy is designed and the stability of reduced state of the system is proved using perturbation method.

A computed torque method based attitude control with optimal force distribution for articulated body mobile robots

International Nuclear Information System (INIS)

Fukushima, Edwardo F.; Hirose, Shigeo

2000-01-01

This paper introduces an attitude control scheme based in optimal force distribution using quadratic programming which minimizes joint energy consumption. This method shares similarities with force distribution for multifingered hands, multiple coordinated manipulators and legged walking robots. In particular, an attitude control scheme was introduced inside the force distribution problem, and successfully implemented for control of the articulated body mobile robot KR-II. This is an actual mobile robot composed of cylindrical segments linked in series by prismatic joints and has a long snake-like appearance. These prismatic joints are force controlled so that each segment's vertical motion can automatically follow the terrain irregularities. An attitude control is necessary because this system acts like a system of wheeled inverted pendulum carts connected in series, being unstable by nature. The validity and effectiveness of the proposed method is verified by computer simulation and experiments with the robot KR-II. (author)

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

Science.gov (United States)

Witus, Gary

2000-07-01

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

Analysis of the Accuracy and Robustness of the Leap Motion Controller

Directory of Open Access Journals (Sweden)

Denis Fisseler

2013-05-01

Full Text Available The Leap Motion Controller is a new device for hand gesture controlled user interfaces with declared sub-millimeter accuracy. However, up to this point its capabilities in real environments have not been analyzed. Therefore, this paper presents a first study of a Leap Motion Controller. The main focus of attention is on the evaluation of the accuracy and repeatability. For an appropriate evaluation, a novel experimental setup was developed making use of an industrial robot with a reference pen allowing a position accuracy of 0.2 mm. Thereby, a deviation between a desired 3D position and the average measured positions below 0.2mmhas been obtained for static setups and of 1.2mmfor dynamic setups. Using the conclusion of this analysis can improve the development of applications for the Leap Motion controller in the field of Human-Computer Interaction.

Path following control of planar snake robots using virtual holonomic constraints: theory and experiments.

Science.gov (United States)

Rezapour, Ehsan; Pettersen, Kristin Y; Liljebäck, Pål; Gravdahl, Jan T; Kelasidi, Eleni

This paper considers path following control of planar snake robots using virtual holonomic constraints. In order to present a model-based path following control design for the snake robot, we first derive the Euler-Lagrange equations of motion of the system. Subsequently, we define geometric relations among the generalized coordinates of the system, using the method of virtual holonomic constraints. These appropriately defined constraints shape the geometry of a constraint manifold for the system, which is a submanifold of the configuration space of the robot. Furthermore, we show that the constraint manifold can be made invariant by a suitable choice of feedback. In particular, we analytically design a smooth feedback control law to exponentially stabilize the constraint manifold. We show that enforcing the appropriately defined virtual holonomic constraints for the configuration variables implies that the robot converges to and follows a desired geometric path. Numerical simulations and experimental results are presented to validate the theoretical approach.

Real-Time Control of an Exoskeleton Hand Robot with Myoelectric Pattern Recognition.

Science.gov (United States)

Lu, Zhiyuan; Chen, Xiang; Zhang, Xu; Tong, Kay-Yu; Zhou, Ping

2017-08-01

Robot-assisted training provides an effective approach to neurological injury rehabilitation. To meet the challenge of hand rehabilitation after neurological injuries, this study presents an advanced myoelectric pattern recognition scheme for real-time intention-driven control of a hand exoskeleton. The developed scheme detects and recognizes user's intention of six different hand motions using four channels of surface electromyography (EMG) signals acquired from the forearm and hand muscles, and then drives the exoskeleton to assist the user accomplish the intended motion. The system was tested with eight neurologically intact subjects and two individuals with spinal cord injury (SCI). The overall control accuracy was [Formula: see text] for the neurologically intact subjects and [Formula: see text] for the SCI subjects. The total lag of the system was approximately 250[Formula: see text]ms including data acquisition, transmission and processing. One SCI subject also participated in training sessions in his second and third visits. Both the control accuracy and efficiency tended to improve. These results show great potential for applying the advanced myoelectric pattern recognition control of the wearable robotic hand system toward improving hand function after neurological injuries.

Imposing motion constraints to a force reflecting tele-robot through real-time simulation of a virtual mechanism

Energy Technology Data Exchange (ETDEWEB)

Joly, L.; Andriot, C.

1995-12-31

In a tele-operation system, assistance can be given to the operator by constraining the tele-robot position to remain within a restricted subspace of its workspace. A new approach to motion constraint is presented in this paper. The control law is established simulating a virtual ideal mechanism acting as a jig, and connected to the master and slave arms via springs and dampers. Using this approach, it is possible to impose any (sufficiently smooth) motion constraint to the system, including non linear constraints (complex surfaces) involving coupling between translations and rotations and physical equivalence ensures that the controller is passive. Experimental results obtained with a 6-DOF tele-operation system are given. Other applications of the virtual mechanism concept include hybrid position-force control and haptic interfaces. (authors). 11 refs., 7 figs.

Imposing motion constraints to a force reflecting tele-robot through real-time simulation of a virtual mechanism

International Nuclear Information System (INIS)

Joly, L.; Andriot, C.

1995-01-01

In a tele-operation system, assistance can be given to the operator by constraining the tele-robot position to remain within a restricted subspace of its workspace. A new approach to motion constraint is presented in this paper. The control law is established simulating a virtual ideal mechanism acting as a jig, and connected to the master and slave arms via springs and dampers. Using this approach, it is possible to impose any (sufficiently smooth) motion constraint to the system, including non linear constraints (complex surfaces) involving coupling between translations and rotations and physical equivalence ensures that the controller is passive. Experimental results obtained with a 6-DOF tele-operation system are given. Other applications of the virtual mechanism concept include hybrid position-force control and haptic interfaces. (authors). 11 refs., 7 figs

Multibody system dynamics, robotics and control

CERN Document Server

Gerstmayr, Johannes

2013-01-01

The volume contains 19 contributions by international experts in the field of multibody system dynamics, robotics and control. The book aims to bridge the gap between the modeling of mechanical systems by means of multibody dynamics formulations and robotics. In the classical approach, a multibody dynamics model contains a very high level of detail, however, the application of such models to robotics or control is usually limited. The papers aim to connect the different scientific communities in multibody dynamics, robotics and control. Main topics are flexible multibody systems, humanoid robots, elastic robots, nonlinear control, optimal path planning, and identification.

Robot performing heavy gymnastics. Kikai taiso wo suru robot

Energy Technology Data Exchange (ETDEWEB)

Takashima, S. (Hosei Univ., Tokyo (Japan). Faculty of Engineering)

1991-11-01

Methods of simulation of the motion of human bodies and the control of the motion of bobots are sdudied in order to realize robots to perform gymnastics on a horizontal bar. A model of the human body structure is presented by dividing the human body into 8 parts: right and left arms, the head, the trunk, the right and left thighs, and the right and left foot, and a system is constructed by combination of the links of the rigid partswith an assumption on each link for simplification. A method to enhance the swing motion is devised in order to produce a suspension motionaas a basic movement of horizontal bar gymnastics. The basic condition to control the horizontal bar gynnastics and the control system of an articulation angle are considered. Two algorithms are presented in order to enhance the swing motion and to maintain suspension swing: excitation of the swing by a vertical motion of the center of gravity and excitation by the use of natural frequency. Computer simulation of suspension swing is executed and the results are shown in a figure. A prototype robot to perform horizontal bar gymnastics is manufactured and performs suspension swing, starting of swing, kip motion and giant swing. The concept of optimization is not included concretely in the prototype. 22 refs., 8 figs.

Anti-Swing Control of Suspended Loads on Shipboard Robotic Cranes

Directory of Open Access Journals (Sweden)

Jackrit Suthakorn

2005-02-01

Full Text Available Currently, the speed at which materials can be transferred between ships at sea is limited by sea conditions. Rough sea conditions cause the payload to swing making load transfer difficult and time-consuming. The objective of this research is to develop a real-time, command compensating control for reducing sea state induced payload swing for shipboard robotic cranes. The future use of this control strategy will be to facilitate faster "ship-to-ship" payload transfer in rough sea conditions. In this study, only the sea-induced rotational motion of the ship is considered, since it is assumed that a station-keeping control maintains a constant position of the ship. This rotational motion is modelled using pitch-yaw-roll Euler angles. The shipboard robotic crane is modelled as a spherical pendulum attached to a three-degree-of-freedom manipulator. The three degrees-of-freedom are azimuth (rotation about an axis normal to the ship's deck, elevation (rotation about an axis parallel with the ship's deck, also referred to as luffing, and lift-line length. An inverse kinematics based approach and a sliding mode control strategy are explored. Both approaches use the azimuth and the elevation capability of the crane manipulator to maintain a horizontal position of the suspended load to reduce sea-induced payload sway.

sEMG-based joint force control for an upper-limb power-assist exoskeleton robot.

Science.gov (United States)

Li, Zhijun; Wang, Baocheng; Sun, Fuchun; Yang, Chenguang; Xie, Qing; Zhang, Weidong

2014-05-01

This paper investigates two surface electromyogram (sEMG)-based control strategies developed for a power-assist exoskeleton arm. Different from most of the existing position control approaches, this paper develops force control methods to make the exoskeleton robot behave like humans in order to provide better assistance. The exoskeleton robot is directly attached to a user's body and activated by the sEMG signals of the user's muscles, which reflect the user's motion intention. In the first proposed control method, the forces of agonist and antagonist muscles pair are estimated, and their difference is used to produce the torque of the corresponding joints. In the second method, linear discriminant analysis-based classifiers are introduced as the indicator of the motion type of the joints. Then, the classifier's outputs together with the estimated force of corresponding active muscle determine the torque control signals. Different from the conventional approaches, one classifier is assigned to each joint, which decreases the training time and largely simplifies the recognition process. Finally, the extensive experiments are conducted to illustrate the effectiveness of the proposed approaches.

The Application of Euler-Lagrange Method of Optimization for Electromechanical Motion Control

Directory of Open Access Journals (Sweden)

Cristian VASILACHE

2000-12-01

Full Text Available Industrial and non-industrial processes such as production plans, robots, pumps, compressors, home applications, transportation of people and goods etc., require some kinds of motion control. The main functions of electromechanical drives are to adjust these processes by controlling the torque, speed or position. The objective of this paper is to perform the control of motion while minimizing power losses, that is ∫Ri2dt, in process conversion of electrical energy to mechanical energy. The optimal control laws for our problem is find using the Euler - Lagrange principle. We consider three types of controlled drives: torque, speed and position. Each of them has different control laws. By implementation of these controls with Borland C++ and Matlab environment, substantial energy savings are obtained.

Controller Design Of Unicycle Mobile Robot

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Mohd Zamzuri Abd Rashid

2012-10-01

Full Text Available ABSTRACT: The ability of unicycle mobile robot to stand and move around using one wheel has attracted a lot of researchers to conduct studies about the system, particularly in the design of the system mechanisms and the control strategies. This paper reports the investigation done on the design of the controller of the unicycle mobile robot system to maintain its stability in both longitudinal and lateral directions. The controller proposed is a Linear Quadratic Controller (LQR type which is based on the linearized model of the system. A thorough simulation studies have been carried out to find out the performance of the LQR controller. The best controller gain, K acquired through the simulation is selected to be implemented and tested in the experimental hardware. Finally, the results obtained from the experimental study are compared to the simulation results to study the controller efficacy. The analysis reveals that the proposed controller design is able to stabilize the unicycle mobile robot.ABSTRAK: Kemampuan robot satu roda untuk berdiri dan bergerak di sekitar telah menarik minat ramai penyelidik untuk mengkaji sistem robot terutamanya didalam bidang rangka mekanikal dan strategi kawalan robot. Kertas kajian ini melaporkan hasil penyelidikan ke atas strategi kawalan robot bagi memastikan sistem robot satu roda dapat distabilkan dari arah sisi dan hadapan. Strategi kawalan yang dicadang, menggunakan teknik kawalan kuadratik sejajar (Linear Quadratic Control yang berdasarkan model robot yang telah dipermudahkan. Kajian simulasi secara terperinci telah dijalankan bagi mengkaji prestasi strategi kawalan yang dicadangkan. Dari kajian simulasi sistem robot, pemilihan faktor konstan, K yang sesuai di dalam strategi kawalan telah dibuat, agar dapat dilaksanakan ke atas sistem robot yang dibangunkan. Keputusan dari kajian simulasi dan tindak balas oleh sistem robot yang dibangunkan akhirnya dibandingkan bagi melihat kesesuaian faktor kostan, K

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)

Active Head Motion Compensation of TMS Robotic System Using Neuro-Fuzzy Estimation

Directory of Open Access Journals (Sweden)

Wan Zakaria W.N.

2016-01-01

Full Text Available Transcranial Magnetic Stimulation (TMS allows neuroscientist to study human brain behaviour and also become an important technique for changing the activity of brain neurons and the functions they sub serve. However, conventional manual procedure and robotized TMS are currently unable to precisely position the TMS coil because of unconstrained subject’s head movement and excessive contact force between the coil and subject’s head. This paper addressed this challenge by proposing an adaptive neuro-fuzzy force control to enable low contact force with a moving target surface. A learning and adaption mechanism is included in the control scheme to improve position disturbance estimation. The results show the ability of the proposed force control scheme to compensate subject’s head motions while maintaining desired contact force, thus allowing for more accurate and repeatable TMS procedures.

Vision-Based Robot Following Using PID Control

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Chandra Sekhar Pati

2017-06-01

Full Text Available Applications like robots which are employed for shopping, porter services, assistive robotics, etc., require a robot to continuously follow a human or another robot. This paper presents a mobile robot following another tele-operated mobile robot based on a PID (Proportional–Integral-Differential controller. Here, we use two differential wheel drive robots; one is a master robot and the other is a follower robot. The master robot is manually controlled and the follower robot is programmed to follow the master robot. For the master robot, a Bluetooth module receives the user’s command from an android application which is processed by the master robot’s controller, which is used to move the robot. The follower robot receives the image from the Kinect sensor mounted on it and recognizes the master robot. The follower robot identifies the x, y positions by employing the camera and the depth by using the Kinect depth sensor. By identifying the x, y, and z locations of the master robot, the follower robot finds the angle and distance between the master and follower robot, which is given as the error term of a PID controller. Using this, the follower robot follows the master robot. A PID controller is based on feedback and tries to minimize the error. Experiments are conducted for two indigenously developed robots; one depicting a humanoid and the other a small mobile robot. It was observed that the follower robot was easily able to follow the master robot using well-tuned PID parameters.

Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

Science.gov (United States)

Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

2014-01-01

This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian motion module. The needle driver provides needle cannula translation and rotation (2-DOF) and stylet translation (1-DOF). A custom robot controller consisting of multiple piezoelectric motor drivers provides precision closed-loop control of piezoelectric motors and enables simultaneous robot motion and MR imaging. The developed modular robot control interface software performs image-based registration, kinematics calculation, and exchanges robot commands and coordinates between the navigation software and the robot controller with a new implementation of the open network communication protocol OpenIGTLink. Comprehensive compatibility of the robot is evaluated inside a 3-Tesla MRI scanner using standard imaging sequences and the signal-to-noise ratio (SNR) loss is limited to 15%. The image deterioration due to the present and motion of robot demonstrates unobservable image interference. Twenty-five targeted needle placements inside gelatin phantoms utilizing an 18-gauge ceramic needle demonstrated 0.87 mm root mean square (RMS) error in 3D Euclidean distance based on MRI volume segmentation of the image-guided robotic needle placement procedure. PMID:26412962

Autonomous Coordination and Online Motion Modeling for Mobile Robots

National Research Council Canada - National Science Library

Sjoberg, Eric J

2007-01-01

Robots are rapidly becoming more involved in everyday military operations. As robots become more capable, their tasks will increase to include such roles as exploring enemy controlled buildings and caves...

A Comparative Study of Control Methods for a Robotic Manipulator with Six DOF in Simulation

Directory of Open Access Journals (Sweden)

Smyrnaiou Georgia P.

2017-01-01

Full Text Available In this paper a comparative study of the classical control methods for the testing of a mathematical model, which controls six actuators of a six degrees of freedom robotic arm with a single controller, is illustrated, aiming to the constructive simplification of the system. In more detail, a mathematical model of the system is designed which simulates all mechanical parts, including 5-way directional pneumatic valve, the pneumatic actuators/pistons and the mathematical model of the controller. The purpose of the above is the tuning of a Single Input, Multiple Output (SIMO controller which will direct the motion of the six pneumatic pistons. The thorough analysis of the implementation of the pneumatic system in Matlab/Simulink environment is followed by experimentation and results using Proportional (P, Proportional-Integral (PI, Proportional-Derivative (PD and Proportional-Integral-Derivative (PID controllers. The simulation results show the advantages of the above classical control methods on the robotic human arm which imitating human motion and made by a well-known company in the field of pneumatic automation.

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

Shape memory alloy-based small crawling robots inspired by C. elegans

Energy Technology Data Exchange (ETDEWEB)

Yuk, Hyunwoo; Kim, Daeyeon; Shin, Jennifer H [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon (Korea, Republic of); Lee, Honggu; Jo, Sungho, E-mail: shjo@kaist.ac.kr, E-mail: j_shin@kaist.ac.kr [Department of Computer Science, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon (Korea, Republic of)

2011-12-15

Inspired by its simple musculature, actuation and motion mechanisms, we have developed a small crawling robot that closely mimics the model organism of our choice: Caenorhabditis elegans. A thermal shape memory alloy (SMA) was selected as an actuator due to the similarities of its properties to C. elegans muscles. Based on the anatomy of C. elegans, a 12-unit robot was designed to generate a sinusoidal undulating motion. Each body unit consisting of a pair of SMA actuators is serially connected by rigid links with an embedded motion control circuit. A simple binary operation-based motion control mechanism was implemented using a microcontroller. The assembled robot can execute C. elegans-like motion with a 0.17 Hz undulation frequency. Its motion is comparable to that of a real worm.

Bio-inspired motion planning algorithms for autonomous robots facilitating greater plasticity for security applications

Science.gov (United States)

Guo, Yi; Hohil, Myron; Desai, Sachi V.

2007-10-01

Proposed are techniques toward using collaborative robots for infrastructure security applications by utilizing them for mobile sensor suites. A vast number of critical facilities/technologies must be protected against unauthorized intruders. Employing a team of mobile robots working cooperatively can alleviate valuable human resources. Addressed are the technical challenges for multi-robot teams in security applications and the implementation of multi-robot motion planning algorithm based on the patrolling and threat response scenario. A neural network based methodology is exploited to plan a patrolling path with complete coverage. Also described is a proof-of-principle experimental setup with a group of Pioneer 3-AT and Centibot robots. A block diagram of the system integration of sensing and planning will illustrate the robot to robot interaction to operate as a collaborative unit. The proposed approach singular goal is to overcome the limits of previous approaches of robots in security applications and enabling systems to be deployed for autonomous operation in an unaltered environment providing access to an all encompassing sensor suite.

Collective Motion of Robotic Fish Synchronized with Antiphases

NARCIS (Netherlands)

Wang, Chen; Cao, Ming; Xie, Guangming

2011-01-01

The study of design principles for individual robotic fish can be traced back to at least the early 1990’s. More recently, different central pattern generator (CPG) models have been utilized to control the locomotions of robotic fish and some results have been reported to use proper sensing and

Vision-Based Robot Following Using PID Control

OpenAIRE

Chandra Sekhar Pati; Rahul Kala

2017-01-01

Applications like robots which are employed for shopping, porter services, assistive robotics, etc., require a robot to continuously follow a human or another robot. This paper presents a mobile robot following another tele-operated mobile robot based on a PID (Proportional–Integral-Differential) controller. Here, we use two differential wheel drive robots; one is a master robot and the other is a follower robot. The master robot is manually controlled and the follower robot is programmed to ...

An integrated movement capture and control platform applied towards autonomous movements of surgical robots.

Science.gov (United States)

Daluja, Sachin; Golenberg, Lavie; Cao, Alex; Pandya, Abhilash K; Auner, Gregory W; Klein, Michael D

2009-01-01

Robotic surgery has gradually gained acceptance due to its numerous advantages such as tremor filtration, increased dexterity and motion scaling. There remains, however, a significant scope for improvement, especially in the areas of surgeon-robot interface and autonomous procedures. Previous studies have attempted to identify factors affecting a surgeon's performance in a master-slave robotic system by tracking hand movements. These studies relied on conventional optical or magnetic tracking systems, making their use impracticable in the operating room. This study concentrated on building an intrinsic movement capture platform using microcontroller based hardware wired to a surgical robot. Software was developed to enable tracking and analysis of hand movements while surgical tasks were performed. Movement capture was applied towards automated movements of the robotic instruments. By emulating control signals, recorded surgical movements were replayed by the robot's end-effectors. Though this work uses a surgical robot as the platform, the ideas and concepts put forward are applicable to telerobotic systems in general.

Robotic arm

Science.gov (United States)

Kwech, Horst

1989-04-18

A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel.

Cooperative Three-Robot System for Traversing Steep Slopes

Science.gov (United States)

Stroupe, Ashley; Huntsberger, Terrance; Aghazarian, Hrand; Younse, Paulo; Garrett, Michael

2009-01-01

from all three robots for decision- making at each step, and to control the physical connections among the robots. In addition, TRESSA (as in prior systems that have utilized this architecture) , incorporates a capability for deterministic response to unanticipated situations from yet another architecture reported in Control Architecture for Robotic Agent Command and Sensing (NPO-43635), NASA Tech Briefs, Vol. 32, No. 10 (October 2008), page 40. Tether tension control is a major consideration in the design and operation of TRESSA. Tension is measured by force sensors connected to each tether at the Cliffbot. The direction of the tension (both azimuth and elevation) is also measured. The tension controller combines a controller to counter gravitational force and an optional velocity controller that anticipates the motion of the Cliffbot. The gravity controller estimates the slope angle from the inclination of the tethers. This angle and the weight of the Cliffbot determine the total tension needed to counteract the weight of the Cliffbot. The total needed tension is broken into components for each Anchorbot. The difference between this needed tension and the tension measured at the Cliffbot constitutes an error signal that is provided to the gravity controller. The velocity controller computes the tether speed needed to produce the desired motion of the Cliffbot. Another major consideration in the design and operation of TRESSA is detection of faults. Each robot in the TRESSA system monitors its own performance and the performance of its teammates in order to detect any system faults and prevent unsafe conditions. At startup, communication links are tested and if any robot is not communicating, the system refuses to execute any motion commands. Prior to motion, the Anchorbots attempt to set tensions in the tethers at optimal levels for counteracting the weight of the Cliffbot; if either Anchorbot fails to reach its optimal tension level within a specified time, it sends

Characterization Of Robot Work Cell

Science.gov (United States)

Anderson, Ronald R.; Paternoster, Vincent Y.; Guthmiller, Wayne A.

1990-01-01

Iterative process of measurement and computation used to characterize work cell of robot, increasing accuracy of mathematical model of work cell. Characterization needed because model used in off-line programming (OLP) to compute paths to control motion of robot. Increases accuracies of model and paths.

Motion control report

CERN Document Server

2013-01-01

Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

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

Introducing geometric constraint expressions into robot constrained motion specification and control

NARCIS (Netherlands)

Borghesan, G.; Scioni, E.; Kheddar, A.; Bruyninckx, H.P.J.

2016-01-01

The problem of robotic task definition and execution was pioneered by Mason, who defined setpoint constraints where the position, velocity, and/or forces are expressed in one particular task frame for a 6-DOF robot. Later extensions generalized this approach to constraints in 1) multiple frames; 2)

Parametric motion control of robotic arms: A biologically based approach using neural networks

Science.gov (United States)

Bock, O.; D'Eleuterio, G. M. T.; Lipitkas, J.; Grodski, J. J.

1993-01-01

A neural network based system is presented which is able to generate point-to-point movements of robotic manipulators. The foundation of this approach is the use of prototypical control torque signals which are defined by a set of parameters. The parameter set is used for scaling and shaping of these prototypical torque signals to effect a desired outcome of the system. This approach is based on neurophysiological findings that the central nervous system stores generalized cognitive representations of movements called synergies, schemas, or motor programs. It has been proposed that these motor programs may be stored as torque-time functions in central pattern generators which can be scaled with appropriate time and magnitude parameters. The central pattern generators use these parameters to generate stereotypical torque-time profiles, which are then sent to the joint actuators. Hence, only a small number of parameters need to be determined for each point-to-point movement instead of the entire torque-time trajectory. This same principle is implemented for controlling the joint torques of robotic manipulators where a neural network is used to identify the relationship between the task requirements and the torque parameters. Movements are specified by the initial robot position in joint coordinates and the desired final end-effector position in Cartesian coordinates. This information is provided to the neural network which calculates six torque parameters for a two-link system. The prototypical torque profiles (one per joint) are then scaled by those parameters. After appropriate training of the network, our parametric control design allowed the reproduction of a trained set of movements with relatively high accuracy, and the production of previously untrained movements with comparable accuracy. We conclude that our approach was successful in discriminating between trained movements and in generalizing to untrained movements.

Increasing The Dexterity Of Redundant Robots

Science.gov (United States)

Seraji, Homayoun

1990-01-01

Redundant coordinates used to define additional tasks. Configuration control emerging as effective way to control motions of robot having more degrees of freedom than necessary to define trajectory of end effector and/or of object to be manipulated. Extra or redundant degrees of freedom used to give robot humanlike dexterity and versatility.

24th International Conference on Robotics in Alpe-Adria-Danube Region

CERN Document Server

2016-01-01

This volume includes the Proceedings of the 24th International Conference on Robotics in Alpe-Adria-Danube Region, RAAD 2015, which was held in Bucharest, Romania, on May 27-29, 2015. The Conference brought together academic and industry researchers in robotics from the 11 countries affiliated to the Alpe-Adria-Danube space: Austria, Croatia, Czech Republic, Germany, Greece, Hungary, Italy, Romania, Serbia, Slovakia and Slovenia, and their worldwide partners. According to its tradition, RAAD 2015 covered all important areas of research, development and innovation in robotics, including new trends such as: bio-inspired and cognitive robots, visual servoing of robot motion, human-robot interaction, and personal robots for ambient assisted living. The accepted papers have been grouped in nine sessions: Robot integration in industrial applications; Grasping analysis, dexterous grippers and component design; Advanced robot motion control; Robot vision and sensory control; Human-robot interaction and collaboration;...

Measurement of the Robot Motor Capability of a Robot Motor System: A Fitts’s-Law-Inspired Approach

OpenAIRE

C. S. George Lee; Hsien-I Lin

2013-01-01

Robot motor capability is a crucial factor for a robot, because it affects how accurately and rapidly a robot can perform a motion to accomplish a task constrained by spatial and temporal conditions. In this paper, we propose and derive a pseudo-index of motor performance (pIp ) to characterize robot motor capability with robot kinematics, dynamics and control taken into consideration. The proposed pIp provides a quantitative measure for a robot with revolute joints, which is inspired from an...

Sistem kontrol gerak kinematika robot gripper manipulator

Directory of Open Access Journals (Sweden)

Wayan Widhiada

2018-01-01

are usually interact with the system, and in industrial activity is usually referred to as a gripper hand. The author uses the method of simulation techniques to determine the robot kinematics motion systems. Simulation technique is a method used to design and analyze the movement of the robot where the results of robot movement response to the result obtained in actual circumstances. Simulations can also save time and costs used in designing the robot gripper manipulator five fingers with prismatic elements. By using the PID control is expected kinematic motion response of each joint robot manipulator achieve best perfomance as small overshoot, and calm conditions (steady state within a short time accompanied by a small driving keselahan. Advance through the process of tuning PID parameters obtained complete control amplifier at PID control is Kp = 0.7194, Ki = 8,306 and Kd = 0.0061 so that the best performance kinematic motion for robot gripper manipulator is achieved as desired by the user with a short rise time of 12:52 seconds, time 0:52 seconds short peak, small overshoot maximum 1.8%, kesetebailan response was achieved in 0.76 seconds and a very small driving mistakes 12:32%. Keywords: Robot gripper manipulator, PID control, kinematics motion

Teen Sized Humanoid Robot: Archie

Science.gov (United States)

Baltes, Jacky; Byagowi, Ahmad; Anderson, John; Kopacek, Peter

This paper describes our first teen sized humanoid robot Archie. This robot has been developed in conjunction with Prof. Kopacek’s lab from the Technical University of Vienna. Archie uses brushless motors and harmonic gears with a novel approach to position encoding. Based on our previous experience with small humanoid robots, we developed software to create, store, and play back motions as well as control methods which automatically balance the robot using feedback from an internal measurement unit (IMU).

Translational control of a graphically simulated robot arm by kinematic rate equations that overcome elbow joint singularity

Science.gov (United States)

Barker, L. K.; Houck, J. A.; Carzoo, S. W.

1984-01-01

An operator commands a robot hand to move in a certain direction relative to its own axis system by specifying a velocity in that direction. This velocity command is then resolved into individual joint rotational velocities in the robot arm to effect the motion. However, the usual resolved-rate equations become singular when the robot arm is straightened. To overcome this elbow joint singularity, equations were developed which allow continued translational control of the robot hand even though the robot arm is (or is nearly) fully extended. A feature of the equations near full arm extension is that an operator simply extends and retracts the robot arm to reverse the direction of the elbow bend (difficult maneuver for the usual resolved-rate equations). Results show successful movement of a graphically simulated robot arm.

Robotic arm

International Nuclear Information System (INIS)

Kwech, H.

1989-01-01

A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube is disclosed. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel. 23 figs

Optimal Design for PID Controller Based on DE Algorithm in Omnidirectional Mobile Robot

Directory of Open Access Journals (Sweden)

Wu Peizhang

2017-01-01

Full Text Available This paper introduces a omnidirectional mobile robot based on Mecanum wheel, which is used for conveying heavy load in a small space of the automatic warehousing logistics center. Then analyzes and establishes the omnidirectional chassis inverse and forward kinematic model. In order to improve the performance of motion, the paper proposes the optimal PID controller based on differential evolution algorithm. Finally, through MATLAB simulation, the results show that the kinematic model of mobile robot chassis is correct, further more the controller optimized by the DE algorithm working better than the traditional Z-N PID tuned. So the optimal scheme is reasonable and feasible, which has a value for engineering applications.

Design and development of an upper extremity motion capture system for a rehabilitation robot.

Science.gov (United States)

Nanda, Pooja; Smith, Alan; Gebregiorgis, Adey; Brown, Edward E

2009-01-01

Human robot interaction is a new and rapidly growing field and its application in the realm of rehabilitation and physical care is a major focus area of research worldwide. This paper discusses the development and implementation of a wireless motion capture system for the human arm which can be used for physical therapy or real-time control of a robotic arm, among many other potential applications. The system is comprised of a mechanical brace with rotary potentiometers inserted at the different joints to capture position data. It also contains surface electrodes which acquire electromyographic signals through the CleveMed BioRadio device. The brace interfaces with a software subsystem which displays real time data signals. The software includes a 3D arm model which imitates the actual movement of a subject's arm under testing. This project began as part of the Rochester Institute of Technology's Undergraduate Multidisciplinary Senior Design curriculum and has been integrated into the overall research objectives of the Biomechatronic Learning Laboratory.

A path planning method for robot end effector motion using the curvature theory of the ruled surfaces

Science.gov (United States)

Güler, Fatma; Kasap, Emin

Using the curvature theory for the ruled surfaces a technique for robot trajectory planning is presented. This technique ensures the calculation of robot’s next path. The positional variation of the Tool Center Point (TCP), linear velocity, angular velocity are required in the work area of the robot. In some circumstances, it may not be physically achievable and a re-computation of the robot trajectory might be necessary. This technique is suitable for re-computation of the robot trajectory. We obtain different robot trajectories which change depending on the darboux angle function and define trajectory ruled surface family with a common trajectory curve with the rotation trihedron. Also, the motion of robot end effector is illustrated with examples.

Neuro-Inspired Spike-Based Motion: From Dynamic Vision Sensor to Robot Motor Open-Loop Control through Spike-VITE

Directory of Open Access Journals (Sweden)

Fernando Perez-Peña

2013-11-01

Full Text Available In this paper we present a complete spike-based architecture: from a Dynamic Vision Sensor (retina to a stereo head robotic platform. The aim of this research is to reproduce intended movements performed by humans taking into account as many features as possible from the biological point of view. This paper fills the gap between current spike silicon sensors and robotic actuators by applying a spike processing strategy to the data flows in real time. The architecture is divided into layers: the retina, visual information processing, the trajectory generator layer which uses a neuroinspired algorithm (SVITE that can be replicated into as many times as DoF the robot has; and finally the actuation layer to supply the spikes to the robot (using PFM. All the layers do their tasks in a spike-processing mode, and they communicate each other through the neuro-inspired AER protocol. The open-loop controller is implemented on FPGA using AER interfaces developed by RTC Lab. Experimental results reveal the viability of this spike-based controller. Two main advantages are: low hardware resources (2% of a Xilinx Spartan 6 and power requirements (3.4 W to control a robot with a high number of DoF (up to 100 for a Xilinx Spartan 6. It also evidences the suitable use of AER as a communication protocol between processing and actuation.

Neuro-Inspired Spike-Based Motion: From Dynamic Vision Sensor to Robot Motor Open-Loop Control through Spike-VITE

Science.gov (United States)

Perez-Peña, Fernando; Morgado-Estevez, Arturo; Linares-Barranco, Alejandro; Jimenez-Fernandez, Angel; Gomez-Rodriguez, Francisco; Jimenez-Moreno, Gabriel; Lopez-Coronado, Juan

2013-01-01

In this paper we present a complete spike-based architecture: from a Dynamic Vision Sensor (retina) to a stereo head robotic platform. The aim of this research is to reproduce intended movements performed by humans taking into account as many features as possible from the biological point of view. This paper fills the gap between current spike silicon sensors and robotic actuators by applying a spike processing strategy to the data flows in real time. The architecture is divided into layers: the retina, visual information processing, the trajectory generator layer which uses a neuroinspired algorithm (SVITE) that can be replicated into as many times as DoF the robot has; and finally the actuation layer to supply the spikes to the robot (using PFM). All the layers do their tasks in a spike-processing mode, and they communicate each other through the neuro-inspired AER protocol. The open-loop controller is implemented on FPGA using AER interfaces developed by RTC Lab. Experimental results reveal the viability of this spike-based controller. Two main advantages are: low hardware resources (2% of a Xilinx Spartan 6) and power requirements (3.4 W) to control a robot with a high number of DoF (up to 100 for a Xilinx Spartan 6). It also evidences the suitable use of AER as a communication protocol between processing and actuation. PMID:24264330

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)

Utilization of Human-Like Pelvic Rotation for Running Robot

Directory of Open Access Journals (Sweden)

Takuya eOtani

2015-07-01

Full Text Available The spring loaded inverted pendulum (SLIP is used to model human running. It is based on a characteristic feature of human running, in which the linear-spring-like motion of the standing leg is produced by the joint stiffness of the knee and ankle. Although this model is widely used in robotics, it does not include human-like pelvic motion. In this study, we show that the pelvis actually contributes to the increase in jumping force and absorption of landing impact. On the basis of this finding, we propose a new model, SLIP2 (spring loaded inverted pendulum with pelvis, to improve running in humanoid robots. The model is composed of a body mass, a pelvis, and leg springs, and, it can control its springs while running by use of pelvic movement in the frontal plane. To achieve running motions, we developed a running control system that includes a pelvic oscillation controller to attain control over jumping power and a landing placement controller to adjust the running speed. We also developed a new running robot by using the SLIP2 model and performed hopping and running experiments to evaluate the model. The developed robot could accomplish hopping motions only by pelvic movement. The results also established that the difference between the pelvic rotational phase and the oscillation phase of the vertical mass displacement affects the jumping force. In addition, the robot demonstrated the ability to run with a foot placement controller depending on the reference running speed.

Development of haptic system for surgical robot

Science.gov (United States)

Gang, Han Gyeol; Park, Jiong Min; Choi, Seung-Bok; Sohn, Jung Woo

2017-04-01

In this paper, a new type of haptic system for surgical robot application is proposed and its performances are evaluated experimentally. The proposed haptic system consists of an effective master device and a precision slave robot. The master device has 3-DOF rotational motion as same as human wrist motion. It has lightweight structure with a gyro sensor and three small-sized MR brakes for position measurement and repulsive torque generation, respectively. The slave robot has 3-DOF rotational motion using servomotors, five bar linkage and a torque sensor is used to measure resistive torque. It has been experimentally demonstrated that the proposed haptic system has good performances on tracking control of desired position and repulsive torque. It can be concluded that the proposed haptic system can be effectively applied to the surgical robot system in real field.

Multiprocessor development for robot control

International Nuclear Information System (INIS)

Lee, John Min; Kim, Seung Ho; Kim, Chang Hoi; Kim, Byung Soo; Hwang, Suk Yeong; Lee, Young Bum; Sohn, Suk Won; Kim, Woon Gi

1990-01-01

The project of this study is to develop a real time controller applying autonomous robotic systems operated in hostile environment. Developed control system is designed with a multiprocessor to get independency and reliability as well as to extend the system easily. The control system is designed in three distinct subsystems (supervisory control part, functional control part, and remote control part). To review the functional performance of developed controller, a prototype mobile robot, which was installed 4 DOF mainpulator, was designed and manufactured. Initial tests showed that the robot could turn with a radius of 38 cm and a maximum speed of 1.26 km/hr and go over obstacle of 18 cm in height. (author)

Towards Simulation of Custom Industrial Robots

OpenAIRE

Marcu, Cosmin; Robotin, Radu

2008-01-01

In order to create a simulator for custom industrial robots, it is very important to know the forward and inverse kinematics equations of the robot structure, the controller output data and the limitations of the robot mechanical components. In this paper we presented the steps for building a simulation program for a custom industrial robot. The first step was the robot modeling where we obtained the forward and inverse kinematics equations used as motion laws both for the simulated and for t...

Seamless Control of Multi-Fingered Robot Hands Based on Grasp Polyhedrons

Science.gov (United States)

Nagase, Kenji; Shirai, Satoshi; Hayashi, Tsuyoshi

This paper is concerned with a new feedback control design methodology for multi-fingered robot hands applicable to multiple contact situations. As a first step, we especially consider the situations where all the fingers are in contact or not in contact with an object, considering the tasks of catching and releasing the object preceding to or followed by grasping/manipulating the object. Main features of the proposed method are: (1) the direction of the fingertip motion in the non-contact situation is selected to be directly linked to the direction of the object motion and the internal force in the contact situation; (2) by introducing a unified system description for multiple contact situations, a linearizing compensator applicable to multiple contact situations is designed. The controller can handle the tasks with the multiple contact situations by choosing appropriate desired trajectories for the linearizing compensator without switching control architecture. In addition, owing to the selection of the motion in the non-contact situation, all the fingers can approach to the object synchronously along the directions of the object motion and the internal force in the contact situation. A numerical example is shown to prove effectiveness of the proposed method.

Mechanical analysis of flying robot for nuclear safety and security control by radiological monitoring

International Nuclear Information System (INIS)

Cho, Hyo Sung; Woo, Tae Ho

2016-01-01

Highlights: • Radiological monitoring of the NPPs site is performed by the flying robot. • The mechanics of drone is investigated in the NPPs. • Yaw and Pitch motions are simulated for the robotic behaviors. • The flying robot is analyzed for the nuclear safety and security successfully. - Abstract: The flying robot is investigated for the nuclear accident and security treatment. Several mechanics are introduced for the movement of the drone. The optimized motion of the drone should cover all areas of Nuclear Power Plants (NPPs) over the site where the circular and surmounting motions are needed with traverse of zigzag shapes. There is the Yaw motion in the circular moving and the Pitch motion in the climbing and downing against reactor facility. The fallout is calculated from the radiation concentration in the breaking part of the NPPs where the radioactive material leaks from the containment, coolant loop, plant facility and so on. The dose equivalents are obtained where the values are changeable following the random values of the y value, average wind speed, and dispersed concentration in the detection position. The simulation of new positions of x, y, and z are normalized from 0.0 to 1.0. The mechanics of flying robot produces the multidisciplinary converged technology incorporated with the aerial radiation monitoring information.

Out-reach in-space technology experiments program: Control of flexible robot manipulators in zero gravity, experiment definition phase

Science.gov (United States)

Phillips, Warren F.

1989-01-01

The results obtained show that it is possible to control light-weight robots with flexible links in a manner that produces good response time and does not induce unacceptable link vibrations. However, deflections induced by gravity cause large static position errors with such a control system. For this reason, it is not possible to use this control system for controlling motion in the direction of gravity. The control system does, on the other hand, have potential for use in space. However, in-space experiments will be needed to verify its applicability to robots moving in three dimensions.

Controlling Tensegrity Robots Through Evolution

Science.gov (United States)

Iscen, Atil; Agogino, Adrian; SunSpiral, Vytas; Tumer, Kagan

2013-01-01

Tensegrity structures (built from interconnected rods and cables) have the potential to offer a revolutionary new robotic design that is light-weight, energy-efficient, robust to failures, capable of unique modes of locomotion, impact tolerant, and compliant (reducing damage between the robot and its environment). Unfortunately robots built from tensegrity structures are difficult to control with traditional methods due to their oscillatory nature, nonlinear coupling between components and overall complexity. Fortunately this formidable control challenge can be overcome through the use of evolutionary algorithms. In this paper we show that evolutionary algorithms can be used to efficiently control a ball-shaped tensegrity robot. Experimental results performed with a variety of evolutionary algorithms in a detailed soft-body physics simulator show that a centralized evolutionary algorithm performs 400 percent better than a hand-coded solution, while the multi-agent evolution performs 800 percent better. In addition, evolution is able to discover diverse control solutions (both crawling and rolling) that are robust against structural failures and can be adapted to a wide range of energy and actuation constraints. These successful controls will form the basis for building high-performance tensegrity robots in the near future.

On nonlinear dynamics and control of a robotic arm with chaos

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Felix J. L. P.

2014-01-01

Full Text Available In this paper a robotic arm is modelled by a double pendulum excited in its base by a DC motor of limited power via crank mechanism and elastic connector. In the mathematical model, a chaotic motion was identified, for a wide range of parameters. Controlling of the chaotic behaviour of the system, were implemented using, two control techniques, the nonlinear saturation control (NSC and the optimal linear feedback control (OLFC. The actuator and sensor of the device are allowed in the pivot and joints of the double pendulum. The nonlinear saturation control (NSC is based in the order second differential equations and its action in the pivot/joint of the robotic arm is through of quadratic nonlinearities feedback signals. The optimal linear feedback control (OLFC involves the application of two control signals, a nonlinear feedforward control to maintain the controlled system to a desired periodic orbit, and control a feedback control to bring the trajectory of the system to the desired orbit. Simulation results, including of uncertainties show the feasibility of the both methods, for chaos control of the considered system.

Controlling the autonomy of a reconnaissance robot

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Dalgalarrondo, Andre; Dufourd, Delphine; Filliat, David

2004-09-01

In this paper, we present our research on the control of a mobile robot for indoor reconnaissance missions. Based on previous work concerning our robot control architecture HARPIC, we have developed a man machine interface and software components that allow a human operator to control a robot at different levels of autonomy. This work aims at studying how a robot could be helpful in indoor reconnaissance and surveillance missions in hostile environment. In such missions, since a soldier faces many threats and must protect himself while looking around and holding his weapon, he cannot devote his attention to the teleoperation of the robot. Moreover, robots are not yet able to conduct complex missions in a fully autonomous mode. Thus, in a pragmatic way, we have built a software that allows dynamic swapping between control modes (manual, safeguarded and behavior-based) while automatically performing map building and localization of the robot. It also includes surveillance functions like movement detection and is designed for multirobot extensions. We first describe the design of our agent-based robot control architecture and discuss the various ways to control and interact with a robot. The main modules and functionalities implementing those ideas in our architecture are detailed. More precisely, we show how we combine manual controls, obstacle avoidance, wall and corridor following, way point and planned travelling. Some experiments on a Pioneer robot equipped with various sensors are presented. Finally, we suggest some promising directions for the development of robots and user interfaces for hostile environment and discuss our planned future improvements.

A Study on the Bio-mimetic Motion of Reptiles

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Shin, Hochelo; Kim, Changhoi; Eom, Heungseop; Jeong, Kyungmin; Jung, Seungjo

2013-10-15

After investigating the locomotion based on the biological characteristics about the from a literature search about the reptile, the locomotion of lizards is captured with marker based motion capture system. Tested lizards are Cuban anole, bearded dragon, domestic lizards such as a white-striped grass lizard and a leopard lizard, After analyzing the motion of the lizards with the measured data, a 25 DOF kinematics model of a lizard was proposed. A periodic gait of the lizard was modeled by defining gait parameters. The body structure of the lizard was analyzed with a bone specimen for the kinematics modeling. Dynamics parameters such as a mass and a inertia of a link are obtained by measuring the weight and the volume of each link. The crawl and the trot gait were simulated with the dynamics model. To control the poly-morphic motion of snake robot, various locomotions of snakes and the motion algorithm of snake robots were investigated. A test model of snake robot and a control system were developed to analyzed the motion and energy efficiency according to the gaits and to realize the poly-morphic motion control.