Uncalibrated visual servoing of nonholonomic mobile robots

In this paper, an uncalibrated visual servo regulation strategy is designed for a nonholonomic mobile robot equipped with an eye-in-hand camera, which drives the mobile robot to the target pose with exponential convergence. Specifically, a novel fundamental matrix-based algorithm is firstly proposed to rotate the robot to point toward the desired position, with the camera intrinsic parameters estimated simultaneously by employing the fundamental matrix and a projection homography matrix. Subsequently, by utilizing the obtained camera intrinsic parameters, a straight-line motion controller is developed to drive the robot to the desired position, with the orientation of the robot always facing the target position. Another pure rotation controller is finally adopted to correct the orientation error. The exponentially convergent properties of the visual servo errors are proven with mathematical analysis. The performance of the proposed uncalibrated visual servo regulation method is further validated by simulation results.