Abstract
Static friction is a typical nonsmooth phenomenon, and the input deadzone is a specific nonlinearity in an actuator. Both static friction and the input deadzone degrade the performance of control system. In this research, we discuss a controller design for compensating static friction with a backstepping method and an unknown deadzone with an adaptive method. Moreover, the stability proof based on the nonsmooth system analysis is given. The key idea is to compensate the nonsmooth term with the smooth controller and to treat the deadzone as an input-dependent disturbance. The simulation results show the effectiveness of the designed controller for unknown deadzone.