Target Circumnavigation of A Mobile Robot Using Bearing Measurements

This paper deals with a surveillance problem where the objective is to achieve a circular motion around a stationary target using a non-holonomic differentially driven mobile robot. The available information for the robot are its own position, velocity in the inertial frame and the bearing angle of the target with respect to its body frame. Since the position of the target is unknown, an estimator is firstly proposed to obtain such information and then a controller is given to drive the mobile robot circle around the target with a desired radius. Convergence of the proposed algorithms is proven and their performance is demonstrated in simulations, where the estimation errors are shown to approach to a vicinity of zero and the mobile robot asymptotically converges to a small neighborhood of a designed radius.