This paper presents our experience in developing and implementing Internet telerobotics system. Internet telerobotics system refers to a robot system controlled and monitored remotely through the Internet. A robot man...This paper presents our experience in developing and implementing Internet telerobotics system. Internet telerobotics system refers to a robot system controlled and monitored remotely through the Internet. A robot manipulator with five degrees of freedom, called Mentor, is employed. Client-server architecture is chosen as a platform for our Internet telerobotics system. Three generations of telerobotics systems have evolved in this research. The first generation was based on CGI and two tiered architectures, where a client presents a Graphical User Interface to the user, and utilizes the user's data entry and actions to perform requests to robot server running on a different machine. The second generation was developed using Java. We also employ Java 3D for creating and manipulating 3D geometry of manipulator links, and for constructing the structures used in rendering that geometry, resulting in 3D robot movement simulation presented to the users (clients) through their web browser. Recent development in our Internet telerobotics includes object recognition through image captured by a camera, which poses challenging problem, giving the undeterministic latency of the Internet. The third generation is centered around the use of CORBA for development platform of distributed internet telerobotics system, aimed at distributing task of telerobotics system.展开更多
Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization commun...Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization communication driven method is proposed to overcome the negative effects induced by time delay. This method is a non-time based method and it can get rid of the effects of time in the control loop of telerobotics. Stability, transparency and synchronization can be maintained in it by event-driven method. Multimodal enhanced telerobotics is put forward with its feedback including force, video, audio and temperature etc. The use of multimodal feedback improves the efficiency and safety of the whole system. Synchronization in multimodal feedback is hard to ensure and event-driven method is also good for it. Experiments on an Internet-based shaft-hole assemblage system show good results by using event synchronization communication driven method and UDP protocol.展开更多
In telerobotic system for remote welding, human-machine interface is one of the most important factor for enhancing capability and efficiency. This paper presents an architecture design of human-machine interface for ...In telerobotic system for remote welding, human-machine interface is one of the most important factor for enhancing capability and efficiency. This paper presents an architecture design of human-machine interface for welding telerobotic system: welding multi-modal human-machine interface. The human-machine interface integrated several control modes, which are namely shared control, teleteaching, supervisory control and local autonomous control. Space mouse, panoramic vision camera and graphics simulation system are also integrated into the human-machine interface for welding teleoperation. Finally, weld seam tracing and welding experiments of U-shape seam are performed by these control modes respectively. The results show that the system has better performance of human-machine interaction and complexity environment welding.展开更多
3D reconstruction of environment and weld workpiece can provide geometrical model for telerobotic welding and improve its intelligence. A novel framework of spacetime stereo is employed to overcome the lack of texture...3D reconstruction of environment and weld workpiece can provide geometrical model for telerobotic welding and improve its intelligence. A novel framework of spacetime stereo is employed to overcome the lack of texture of the weld workpiece and obtain subpixel disparity map of the scene. Anisotropic diffusion is adopted to smooth the original subpixel disparity map in order to reduce the noise while preserving the depth discontinuity. A simple algorithm of generation triangle mesh surface from the disparity map of the spucetime stereo is presented. The experimental results of real weld scenes are shown.展开更多
A PUMA562 robot has been connected to the Internet and can be controlled through the web browser. The remote user receives still images of robot workspace, coordinates and gripper state and can control the gripper to ...A PUMA562 robot has been connected to the Internet and can be controlled through the web browser. The remote user receives still images of robot workspace, coordinates and gripper state and can control the gripper to pick up blocks and place them to build a structure. An Internet server and a robot server were built to implement this telerobot system. This two-layer server architecture can be used in other Internet-based telerobot system without changing most part of the system.展开更多
This study presents the overall architecture of HeterBot,a heterogeneous mobile manipulation robot developed in our lab,which is designed for versatile operation in hazardous environments.The most significant feature ...This study presents the overall architecture of HeterBot,a heterogeneous mobile manipulation robot developed in our lab,which is designed for versatile operation in hazardous environments.The most significant feature of HeterBot is the heterogeneous design created by adopting the idea of‘big arm+small arm’and‘big car+mini car’.This combination has the advantage of functional complementation,which achieves performance promotion in both locomotion and manipulation capabilities,making HeterBot distinguished from other mobile manipulation robots.Besides,multiple novel technologies are integrated into HeterBot to expand its versatility and ease of use,including Virtual Robot Experimentation Platform-based teleoperation,reconfigurable end effectors,laseraided grasping,and manipulation with customised tools.Experimental results validate the effectiveness of HeterBot in various locomotion and manipulation tasks.HeterBot displays huge potential in future applications,such as searching and rescue.展开更多
In this paper,the problem of time varying telecommunication delays in passive teleoperation systems is addressed.The design comprises delayed position,velocity and position-velocity signals with the local position and...In this paper,the problem of time varying telecommunication delays in passive teleoperation systems is addressed.The design comprises delayed position,velocity and position-velocity signals with the local position and velocity signals of the master and slave manipulators.Nonlinear adaptive control terms are employed locally to cope with uncertain parameters associated with the gravity loading vector of the master and slave manipulators.Lyapunov-Krasovskii function is employed for three methods to establish asymptotic tracking property of the closed loop teleoperation systems.The stability analysis is derived for both symmetrical and unsymmetrical time varying delays in the forward and backward communication channel that connects the local and remote sites.Finally,evaluation results are presented to illustrate the efectiveness of the proposed design for real-time applications.展开更多
The focus of this paper is to address a novel control technique for stability and transparency analysis of bilateral telerobotic systems in the presence of data loss and time delay in the communication channel. Differ...The focus of this paper is to address a novel control technique for stability and transparency analysis of bilateral telerobotic systems in the presence of data loss and time delay in the communication channel. Different control strategies have been reported to compensate the effects of time delay in the communication channel;however, most of them result in poor performance under data loss. First, a model for data loss is proposed using a finite series representation of a set of periodic continuous pulses.To improve the performance and data reconstruction, a holder circuits is also introduced. The passivity of the overall system is provided via the wave variable technique based on the proposed model for the data loss. The stability analysis of the system is then derived using the Lyapunov theorem under the time delay and the data loss. Finally, experimental results are given to illustrate the capability of the proposed control technique.展开更多
Telerobotic systems become more and more important due to emerging hi-technologyand practical requirement in modern society. This paper studies+ and integrates the modeling, taskscheduling, action planning and control...Telerobotic systems become more and more important due to emerging hi-technologyand practical requirement in modern society. This paper studies+ and integrates the modeling, taskscheduling, action planning and control of telerobot systems. Such hybrid syStems often involve coalmunication, command and control, and are so complex that no efficient and simple method could befound to analyze and design systems. To increase the efficiency, reliability and safety oftelrobot syStems,the consideration of task scheduling and action planning in a unified framework could be an importantstep. The discrete-event dynamics is modeled as a linear state-spare equation in Mad-Algebra sense.Performance evaluation can be carried out efficiently. Then analysis about time-delay continuous-timedynamics is given for the scheduling and control, which shows that, to simplify the design procedure,it is necessary to present a good delay scheduling, for example, by changing multi-time-delays to singleones in advance. Robustness conditions are derived using graph theory for dipcrete-event dynamics andmatrix analysis for continuous-time dynamics.展开更多
文摘This paper presents our experience in developing and implementing Internet telerobotics system. Internet telerobotics system refers to a robot system controlled and monitored remotely through the Internet. A robot manipulator with five degrees of freedom, called Mentor, is employed. Client-server architecture is chosen as a platform for our Internet telerobotics system. Three generations of telerobotics systems have evolved in this research. The first generation was based on CGI and two tiered architectures, where a client presents a Graphical User Interface to the user, and utilizes the user's data entry and actions to perform requests to robot server running on a different machine. The second generation was developed using Java. We also employ Java 3D for creating and manipulating 3D geometry of manipulator links, and for constructing the structures used in rendering that geometry, resulting in 3D robot movement simulation presented to the users (clients) through their web browser. Recent development in our Internet telerobotics includes object recognition through image captured by a camera, which poses challenging problem, giving the undeterministic latency of the Internet. The third generation is centered around the use of CORBA for development platform of distributed internet telerobotics system, aimed at distributing task of telerobotics system.
文摘Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization communication driven method is proposed to overcome the negative effects induced by time delay. This method is a non-time based method and it can get rid of the effects of time in the control loop of telerobotics. Stability, transparency and synchronization can be maintained in it by event-driven method. Multimodal enhanced telerobotics is put forward with its feedback including force, video, audio and temperature etc. The use of multimodal feedback improves the efficiency and safety of the whole system. Synchronization in multimodal feedback is hard to ensure and event-driven method is also good for it. Experiments on an Internet-based shaft-hole assemblage system show good results by using event synchronization communication driven method and UDP protocol.
文摘In telerobotic system for remote welding, human-machine interface is one of the most important factor for enhancing capability and efficiency. This paper presents an architecture design of human-machine interface for welding telerobotic system: welding multi-modal human-machine interface. The human-machine interface integrated several control modes, which are namely shared control, teleteaching, supervisory control and local autonomous control. Space mouse, panoramic vision camera and graphics simulation system are also integrated into the human-machine interface for welding teleoperation. Finally, weld seam tracing and welding experiments of U-shape seam are performed by these control modes respectively. The results show that the system has better performance of human-machine interaction and complexity environment welding.
文摘3D reconstruction of environment and weld workpiece can provide geometrical model for telerobotic welding and improve its intelligence. A novel framework of spacetime stereo is employed to overcome the lack of texture of the weld workpiece and obtain subpixel disparity map of the scene. Anisotropic diffusion is adopted to smooth the original subpixel disparity map in order to reduce the noise while preserving the depth discontinuity. A simple algorithm of generation triangle mesh surface from the disparity map of the spucetime stereo is presented. The experimental results of real weld scenes are shown.
文摘A PUMA562 robot has been connected to the Internet and can be controlled through the web browser. The remote user receives still images of robot workspace, coordinates and gripper state and can control the gripper to pick up blocks and place them to build a structure. An Internet server and a robot server were built to implement this telerobot system. This two-layer server architecture can be used in other Internet-based telerobot system without changing most part of the system.
基金supported by the National Natural Science Foundation of China(No.62003188,No.U1813216)Shenzhen Science Fund for Distinguished Young Scholars(No.RCJC20210706091946001)Guangdong Special Branch Plan for Young Talent with Scientific and Technological Innovation(No.2019TQ05Z111).
文摘This study presents the overall architecture of HeterBot,a heterogeneous mobile manipulation robot developed in our lab,which is designed for versatile operation in hazardous environments.The most significant feature of HeterBot is the heterogeneous design created by adopting the idea of‘big arm+small arm’and‘big car+mini car’.This combination has the advantage of functional complementation,which achieves performance promotion in both locomotion and manipulation capabilities,making HeterBot distinguished from other mobile manipulation robots.Besides,multiple novel technologies are integrated into HeterBot to expand its versatility and ease of use,including Virtual Robot Experimentation Platform-based teleoperation,reconfigurable end effectors,laseraided grasping,and manipulation with customised tools.Experimental results validate the effectiveness of HeterBot in various locomotion and manipulation tasks.HeterBot displays huge potential in future applications,such as searching and rescue.
基金supported by Natural Sciences and Engineering Research Council of Canada (NSERC) Research Fellowship,Canada Research Chairs Program and University of Ottawa Research Chair Program
文摘In this paper,the problem of time varying telecommunication delays in passive teleoperation systems is addressed.The design comprises delayed position,velocity and position-velocity signals with the local position and velocity signals of the master and slave manipulators.Nonlinear adaptive control terms are employed locally to cope with uncertain parameters associated with the gravity loading vector of the master and slave manipulators.Lyapunov-Krasovskii function is employed for three methods to establish asymptotic tracking property of the closed loop teleoperation systems.The stability analysis is derived for both symmetrical and unsymmetrical time varying delays in the forward and backward communication channel that connects the local and remote sites.Finally,evaluation results are presented to illustrate the efectiveness of the proposed design for real-time applications.
文摘The focus of this paper is to address a novel control technique for stability and transparency analysis of bilateral telerobotic systems in the presence of data loss and time delay in the communication channel. Different control strategies have been reported to compensate the effects of time delay in the communication channel;however, most of them result in poor performance under data loss. First, a model for data loss is proposed using a finite series representation of a set of periodic continuous pulses.To improve the performance and data reconstruction, a holder circuits is also introduced. The passivity of the overall system is provided via the wave variable technique based on the proposed model for the data loss. The stability analysis of the system is then derived using the Lyapunov theorem under the time delay and the data loss. Finally, experimental results are given to illustrate the capability of the proposed control technique.
文摘Telerobotic systems become more and more important due to emerging hi-technologyand practical requirement in modern society. This paper studies+ and integrates the modeling, taskscheduling, action planning and control of telerobot systems. Such hybrid syStems often involve coalmunication, command and control, and are so complex that no efficient and simple method could befound to analyze and design systems. To increase the efficiency, reliability and safety oftelrobot syStems,the consideration of task scheduling and action planning in a unified framework could be an importantstep. The discrete-event dynamics is modeled as a linear state-spare equation in Mad-Algebra sense.Performance evaluation can be carried out efficiently. Then analysis about time-delay continuous-timedynamics is given for the scheduling and control, which shows that, to simplify the design procedure,it is necessary to present a good delay scheduling, for example, by changing multi-time-delays to singleones in advance. Robustness conditions are derived using graph theory for dipcrete-event dynamics andmatrix analysis for continuous-time dynamics.