Identification of Hammerstein systems in presence of hysteresis-backlash and hysteresis-relay nonlinearities

The problem of identifying Hammerstein systems (HamSys) is addressed in presence of hysteresis-backlash (HB) and hysteresis-relay (HR) nonlinearities. The memory feature makes it impossible to get a system parameterization involving linearly all unknown parameters. Therefore, the linear subsystem and the nonlinear element are estimated separately. The identification process involves appropriate system parameterizations and least-squares like parameter estimators. Specific input signals are designed to guarantee persistent excitation (PE) and estimator consistency.