A Sliding Mode Control law for epipolar visual servoing of differential-drive robots

In this paper, a robust control technique (sliding mode control) is proposed to be used in order to perform visual servoing for differential-drive mobile robots using the classical teach-by-showing strategy. We propose a commuted sliding mode control law that exploits the epipolar geometry. The major contribution of the paper is the design of a control law that solves the problem of passing through a singularity induced by the epipoles maintaining bounded inputs. Moreover, the designed control is able to drive the robot to the target even when it just starts on the singularity. The proposed approach does not need a precise camera calibration due to the robustness of the control system under uncertainty in parameters. It also ensures entire correction of both orientation and lateral error even with noise in the image. The effectiveness of our approach is tested via simulations.