Output feedback sliding mode controller with H2 performance for robot manipulator

In this paper, an output feedback sliding mode controller with performance for position control of uncertain robot manipulators without joint velocity measurement based on a second-order sliding mode observer is presented. First, a second order sliding mode observer with finite time convergence is developed for velocity estimation. Then the robot manipulator is formulated as an error dynamics and a sliding mode control with performance is developed to tackle the unmodeled dynamics and disturbances. The stability properties of the controllers are proved by the Lyapunov method. Asymptotic stability of the closed loop system is proved under a set of nonrestrictive assumptions on the plant and the disturbances. This control law providing smaller errors and better performance to deal with uncertainty and disturbances. Finally, we will use a 2-dof planar robot manipulator to verify the effectiveness of the proposed control scheme.