Page 271 - Adaptive Identification and Control of Uncertain Systems with Nonsmooth Dynamics

272 Adaptive Identification and Control of Uncertain Systems with Non-smooth Dynamics

when the identified dynamics are used in the inverse compensation based
control design.

17.6 CONCLUSION
In this chapter, we introduce a system identification method for modu-
lar systems consisting a linear part and a backlash non-linearity, and then
present an inverse compensation based control to cope with the non-
smooth backlash and achieve output tracking. Firstly, the piecewise linear
parametric expression is used to reformulate the backlash dynamics, which
allows to estimate the backlash characteristic parameters together with the
unknown parameters of the linear part. With the identified parameters, an
inverse model of backlash dynamics is proposed, which is connected with a
robust feedback control in a cascade manner, such that the tracking error of
the system can be guaranteed to converge to arbitrary small neighborhood
of the origin. A numerical simulation is provided to validate the efficacy of
the proposed identification and the associated control methods.

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