Emanuel Slawiñski

Bilateral teleoperation through the Internet

This paper proposes a stable control structure for the bilateral teleoperation of robots through Internet. The problem is motivated by the increasing use of the Internet as a communication channel. Internet has a time-varying delay which depends on factors such as congestion, bandwidth and distance. In this work, we propose a control structure for the teleoperation of a manipulator robot with force feedback. Such a control structure includes state controllers (placed on the local and remote sites) and a time-delay compensation, which modifies the delayed position command generated by the human operator using the force that he feels in such a delayed moment and the current force between the slave and the remote environment. In addition, the proposed control scheme is designed considering a model of the communication channel. Finally, experiments of bilateral teleoperation of robots through Intranet and Internet are shown to test the performance and stability of the designed teleoperation system.

Quantitative Absolute Transparency for Bilateral Teleoperation of Mobile Robots

This paper proposes a new criterion, called absolute transparency, to design control schemes applied to bilateral teleoperation of mobile robots with time-varying delay. The absolute transparency measures how and how fast the human operator and the remote system interact with each other through a teleoperation system. The absolute transparency of different control schemes is analyzed and tested through teleoperation experiments where a human operator drives a mobile robot and receives both visual and force feedback.

Teleoperation of a mobile robot with time-varying delay and force feedback

This paper proposes a prediction system and a command fusion to help the human operator in a teleoperation system of a mobile robot with time-varying delay and force feedback. The command fusion is used to join a remote controller and the delayed users commands. Besides, a predictor is proposed since the future trajectory of the mobile robot is not known a priori being it decided online by the user. The command fusion and predictor are designed based on the time delay and the current context measured through the crash probability. Finally, the proposed scheme is tested from teleoperation experiments considering time-varying delay as well as force feedback.

Bilateral teleoperation of mobile robots

A control structure for the bilateral teleoperation of mobile robots, with tactile feedback and visual information of the interaction force is proposed in this paper. Also an impedance controller is implemented in the mobile robot structure that guarantees the linear velocity be within a desired fixed range without saturation in the actuators. To illustrate the performance of the proposed control structure, experiments on a Pioneer 2 mobile robot teleoperated with a commercial joystick with force feedback are shown.

Online path planning based on Rapidly-Exploring Random Trees

This paper proposes an online path-planning algorithm based on Rapidly-Exploring Random Trees (RRT) applied to the autonomous navigation of a mobile robot. The proposed planner includes two heuristics to improve the performance and generates a set of collision-free paths, from which the one with the most similarity to a reference path given by a supervisor human operator is chosen. This reference can be given a priori when setting the start and goal positions, and be defined as the straight path between them. Simulations and experiments are made to evaluate the performance of the proposed method.

Control scheme including prediction and augmented reality for teleoperation of mobile robots

This paper proposes a control scheme for the teleoperation of a mobile robot in presence of time delay. Our proposal uses a compensation of the time delay based on a human operators model and a simple 3D augmented reality scheme; both are related through a prediction system. Unlike other strategies, the proposed scheme has a model of the human operator inside it, including his decision so that human and robot “push in the same direction.” The stability of the teleoperation system adding the proposed control scheme is proven concluding how the time delay changes the convergence rate and the convergence ball size. Finally, to illustrate the performance and stability of the proposed control structure, several teleoperation experiments in presence of various delays are shown.

Teleoperation of mobile robots with time-varying delay

This paper proposes a stable control structure for the bilateral teleoperation of mobile robots. The proposed control structure includes a time-delay compensation placed on both the local and remote sites of the teleoperation system. To illustrate the performance and stability of the proposed control structure, experiences on a Pioneer 2DX mobile robot teleoperated through a commercial joystick with visual feedback, are shown.

Bilateral teleoperation of mobile robots with delay

This paper proposes a stable control structure for the bilateral teleoperation of mobile robots. The proposed control structure includes a time delay compensation placed on both the local and remote sites of the teleoperation system. To illustrate the performance and stability of the proposed control structure, experiences on a Pioneer 2DX mobile robot teleoperated through a commercial joystick with visual feedback are shown.

Toward safe and stable time-delayed mobile robot teleoperation through sampling-based path planning

This work proposes a teleoperation architecture for mobile robots in partially unknown environments under the presence of variable time delay. The system is provided with artificial intelligence represented by a probabilistic path planner that, in combination with a prediction module, assists the operator while guaranteeing a collision-free motion. For this purpose, a certain level of autonomy is given to the system. The structure was tested in indoor environments for different kinds of operators. A maximum time delay of 2s was successfully coped with.

Stable Teleoperation of Mobile Robots

This paper proposes a stable control scheme for bilateral teleoperation of mobile robots in presence of obstacles and time-varying delay. The proposed control scheme is composed by a velocity controller on board the mobile robot and a time-delay compensation placed on both the local and remote sites of the teleoperation system. Finally, experiments on a mobile robot teleoperated by a human operator with visual feedback through Internet are shown