Indirect Measurement of Nonlinear Effects by State Observers
Vibration and control systems are often influenced by troublesome nonlinear effects such as Coulomb friction, backlash, or hysteresis. In this contribution an indirect measuring technique of the actual values of those nonlinearities is presented. Based on a fictitious model of the time behaviour of the nonlinearities a state observer of an extended dynamical system is designed resulting in estimates of the nonlinear effects. In the paper the theory of this approach, an illustrative example, and a practical application in the position control of robots are considered. The proposed method is a successful tool to register indirectly the nonlinear effects of vibration and control systems.
KeywordsNonlinear Effect State Observer Coulomb Friction Vibration System Identity Observer
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