Robust trajectory tracking control for robot manipulators without velocity measurements

In the paper, the robust trajectory tracking control problem is investigated for robotic manipulators which are not equipped with the velocity sensors. Our contribution consists in establishing the ultimately boundedness in closed-loop system by using the dynamic position-feedback controller with feedforward. Using Lyapunov function method and comparison principle we construct the non-linear controller with variable gain matrices and first-order linear dynamic compensator such that the closed-loop system is ultimately bounded.