Hybrid PD sliding mode control for robotic manipulators

This thesis proposes a new control law for the purpose of providing improved tracking and contouring performance of robotic manipulators. The rationale behind the development of this controller involves the hybridization of existing proportional-derivative (PD) and sliding mode control (SMC) laws. The new control law retains similar ease of implementation as traditional PD/PID controllers with the added benefit of a nonlinear switching component inherent from sliding mode control systems. In addition, it eliminates the need for a priori knowledge of the system dynamics that are required in standard SMC laws. The stability analysis of the proposed control law is conducted through the Lyapunov method. Simulations using linear and nonlinear contours, and under varying dynamic conditions are performed in order to compare its performances to existing control schemes. The proposed hybrid PD-SMC control law is proven to provide good, robust tracking and contouring performance