Adaptive control of systems with backlash acting on the input

Two different adaptive controllers for systems with backlash acting on the input are discussed: one in continuous time and one in discrete time. Both schemes are based on a backlash inverse and a linear controller. The unknown plant parameters and the backlash width are estimated. The estimated parameters are used for pole placement design of the controller and for backlash compensation in the backlash inverse. Some analysis of the estimator convergence is done. Simulations of a second order plant show that both schemes give a nice behavior.