Unified Visual Servoing Tracking and Regulation of Wheeled Mobile Robots With an Uncalibrated Camera

Abstract

In this paper, a vision-based strategy is proposed for the unified tracking and regulation control of a wheeled mobile robot (WMR) equipped with an uncalibrated monocular camera. Specifically, an online implementable method based on the projection homography technique is first proposed to estimate the partial camera intrinsic parameters. By exploiting the obtained camera intrinsic parameters, the orientation and scaled position information of the WMR is extracted from the current, the reference, and the desired images to construct the error system. Then, an adaptive continuous controller is designed to address both the trajectory tracking and regulation problems with input saturation for the WMR. The system uncertainties regarding the distance information and the camera intrinsic parameters are fully taken into consideration as well as the nonholonomic constraint. Moreover, the Lyapunov-based stability analysis is utilized to prove that the proposed controller can achieve asymptotic tracking and regulation in the presence of system uncertainties. Simulation and experimental results validate the effectiveness of the proposed strategy.