Global finite-time adaptive control for uncalibrated robot manipulator based on visual servoing

ISA Trans. 2017 May:68:402-411. doi: 10.1016/j.isatra.2016.10.006. Epub 2017 Mar 11.

Abstract

The paper addresses the finite-time convergence problem of a uncalibrated camera-robot system with uncertainties. These uncertainties include camera extrinsic and intrinsic parameters, robot dynamics and feature depth parameters, which are all considered as time-varying uncertainties. In order to achieve a better dynamic stability performance of the camera-robot system, a novel FTS adaptive controller is presented to cope with rapid convergence problem. Meanwhile, FTS adaptive laws are proposed to handle these uncertainties which exist both in robot and in camera model. The finite-time stability analysis is discussed in accordance with homogeneous theory and Lyapunov function formalism. The control method we proposed extends the asymptotic stability results of visual servoing control to a finite-time stability. Simulation has been conducted to demonstrate the performance of the trajectory tracking errors convergence under control of the proposed method.

Keywords: Adaptive control; Finite-time stability; Lyapunov stability; Visual servoing.