Adaptive Stabilization of a Class of Feedforward Nonlinear Systems Subject to Unknown Backlash-Hysteresis Inputs

A general framework is proposed to stabilize a class of feedforward nonlinear systems subject to backlash-hysteresis inputs. An adaptive controller is conceived to handle both the effects of the system uncertainties and the hysteretic input nonlinearity. The algorithm of state transformation and feedback design with uncertain hysteresis inputs is illustrated through the example of a nonminimum phase mechanical system. Subsequently, the results are extended to hysteretic-single-input-linear systems with an arbitrary structure. Real-time experimental results along with numerical simulations are provided to show the performance of the proposed control algorithms.