Adaptive Finite-Time Synchronization Control for Teleoperation System With Varying Time Delays

Neuro‐adaptive fixed‐time trajectory tracking control for human‐in‐the‐loop teleoperation with mixed communication delays

“…the error states converge to zero as time approaches infinity) and finite-time stability (i.e. the error states reach the origin in a finite time, which is generally positive related to the initial value) of the teleoperation systems in [29,39,48], the proposed algorithm (12)-(15) can achieve the fixed-time stability, in which the error states are forced to the origin within a fixed time regardless of the initial value.…”

“…To deal with such difficulty, the researchers have developed several control algorithms, for example, adaptive control [23], fuzzy control [24], robust control [25], sliding mode control [21] and other methods [26]. Among these algorithms, the sliding mode control plays an important role, and has been widely investigated due to its possible property of finite/fixed-time convergence and strong robustness against uncertainties [21,22,[27][28][29][30]. However, to the authors' best knowledge, how to achieve fixed-time stability for master-slave teleoperation systems in task space remains an open problem.…”

Constrained Control for Cloud Robotic Under Time Delay Based on Command Governor With Interval Estimation

“…Cloud robotic systems allow human operators to extend their capabilities to remote environment, which have been applied to a variety of areas such as remote medical care, industrial manufacturing, outer-space exploration, and so on [1]- [3]. Remote control of robot systems can be performed in a cloud platform through data connection with a robot manipulator, however the existence of time delay between local human operator and remote manipulator is a key and unavoidable problem.…”

Adaptive Finite-Time Control Scheme for Teleoperation With Time-Varying Delay and Uncertainties

“…Yang et al [41] and Wang et al [43], respectively, developed two finite-time controllers based on different nonsingular fast TSMs. Neural network is also introduced to estimate the model uncertainties, and the finite-time control scheme with error constrained [42], new integral TSM [44], and jittering free scheme [45] are, respectively, developed. It is noted that the time-varying delay is not considered in [41]- [43].…”

“…First, many developed adaptive approaches mentioned above are implemented to provide position tracking performance, but force/torque tracking of master-slave robots is not considered (such as in [22]- [29] and [38]- [45]). Second, the position acceleration signals are introduced into the controller for control torque calculation (such as in work [22]- [24], [26]- [30], [40]- [42], [44], [45]). On the one hand, the differential of position error is applied for sliding mode surface and auxiliary variable function designing; on the other hand, the model uncertain part containing the mass inertia matrix is directly estimated by the adaptive method.…”