In this paper, we present identification methods for nonlinear mechatronic
systems. First, we consider a system consisting of a known linear part and
an unknown static nonlinearity, With this approach, using an intelligent ob
server, it is possible to identify the nonlinear characteristic and to esti
mate all unmeasurable system states. The identification result of the nonli
nearity and the estimated system states are used to improve the controller
performance.
Secondly, the first approach is extended to systems where both the linear p
arameters and the nonlinear characteristic are unknown. This is achieved by
implementing the intelligent observer as a structured recurrent neural net
work.