An adaptive controller for nonlinear teleoperators with variable time-delays

作者：Sarras Ioannis; Nuno Emmanuel^*; Basanez Luis

来源：Journal of the Franklin Institute, 2014, 351(10): 4817-4837.

DOI：10.1016/j.jfranklin.2014.07.016

In most real-life bilateral teleoperators the available physical parameters are uncertain and the communications exhibit variable time-delays. In order to confront these situations and only assuming that a bound of the time-delays is known, the present work reports an adaptive controller which ensures asymptotic convergence of both position errors and velocities to zero, provided that a sufficient condition on the control gains is met. Compared to previous related works that only treated constant time-delays, the stability analysis does not rely on the cascade interconnection structure of the local and remote nonlinear dynamics and the linear interconnection map. Instead, the paper employs a different Lyapunov candidate function that incorporates a strictly positive term, the local and remote position error. Some simulations, in free space and interacting with a rigid wall, and experiments, using two nonlinear manipulators, illustrate the performance of the proposed control scheme in the presence of uncertain parameters and variable time-delays.

• 出版日期2014-10