Hammerstein Systems Identification in Presence of Hysteresis-backlash Nonlinearity

The identification of Hammerstein systems is discussed for the systems that include memory nonlinearities. The focus is made on nonlinearities of the hysteresis-backlash type. The linear subsystem and the nonlinear element are identified separately. The identification of the former is dealt with combining an appropriate system parametrization and a specific input signal. The latter is designed so that it provides persistent excitation and makes the internal signal measurable in the considered parametrization. When the model of linear subsystem becomes available, the determination of the nonlinear element turns out to be easier. This is coped with using two appropriate parameterizations and specific input signals. The whole identification method is shown to be consistent.