PROJECT TITLE :

Vision-Based Tracking Control of Underactuated Water Surface Robots Without Direct Position Measurement

ABSTRACT:

Over the past decade, the trajectory tracking of underactuated water surface robots (or boats, surface vessels, etc.) has been an enticing topic in the control and automation community, and numerous controllers are proposed for this challenging downside. However, most, if not all, of the existing trajectory tracking controllers of the underactuated water surface robots assume the global positions of the robots can be accurately measured. In the practical applications, the global position measurement systems are sometimes unstable or maybe unavailable within the working environments of the robots. To avoid the direct position measurement, this transient presents a replacement controller for the trajectory tracking of underactuated water surface robots using monocular visual feedback. This controller works on the idea of a novel adaptive algorithm for estimating world position of the robot on-line using visual feature tracking from a monocular camera, and its orientation and velocity measured by the attitude and heading reference system sensor and a velocity observer. It's proved by Lyapunov theory that the proposed adaptive visual servo controller gives rise to asymptotic tracking of a desired trajectory and convergence of the position estimation to the actual position. Experiments are conducted to validate the effectiveness and robust performance of the proposed controller.