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

Abstract

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 user's 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.

Performance analysis of WLAN based mobile robot teleoperation

“…Here 0 < ϕ MAX < π/2. The second condition in (6) shows that the repulsive force, which multiplies the angular velocity, is active only when the robot turns toward the obstacle. The gain parameters κ v > 0 and κ ω > 0 have to be chosen with respect to maximum velocity values and maximum allowable haptic forces.…”

“…In the papers [4] and [5] it was shown that better haptic reaction can be obtained if the velocity of the robot is also taken into consideration in the force computation. To guarantee that the mobile robot doesn't collide with the obstacles in its environment, papers [6] and [7] propose control schemes that fuse the command action of the user and a predictor algorithm, which takes into consideration the communication delay and the crash probability.…”

Teleoperation of a mobile robot with model-predictive obstacle avoidance control

“…For instance, obstacles may produce repulsive force fields to assist the operator navigating the scene [9], [10] and [11]. Slawinski and Mut [12] found that augmenting obstacle related fictitious forces with predicted position of the vehicle one step ahead can reduce conservativeness of applying unnecessary forces.…”

Passivity-based multilateral control for delayed teleoperation

“…The fictitious force calculated from a potential field in [160] has been applied in a local slave control loop but the computed linear velocity and yaw rate errors are fed back to the master device. In [161], the fictitious force feedback of a virtual potential field has been applied as a feedback force. The system stability was proven via the Lyapunov approach however the feedback loop to the human operator was neglected.…”

“…Still, the overall passivity was not guaranteed and the fictitious force feedback focused here is more complicated since the two slave DoFs are coupled. Also in [161], an approach with a virtual potential field was presented, and a Lyapunov control approach was applied. Still, this stability proof did not consider the feedback loop of the measured force to the operator.…”