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2.12 Summary and Notes                                       101

            EXAMPLE 2.11-5: SPR Design

            Consider the double integrator system










            where c 2≠0 and c 1, c 2 are of the same sign. The open-loop transfer function is
            then





            which has relative degree 1 and is minimum phase. Note that CB=c 2 which is
            invertible. The gain K is chosen to be





            where p>0. The closed-loop system is then





            which is stable for any choice of γ>0 and is SPR if γ>c 1 /(pc 2  (check!).



            2.12 Summary and Notes


            This chapter is meant to be a review of various control theory concepts that
            will be used in the remainder of the book. The emphasis has been to include
            enough material so that readers with little or no background in control theory
            are able to follow the design of robot controllers. Simplifications were often
            made to concentrate on the systems studied in this book, namely, mechanical
            systems and systems described by the Lagrange-Euler equations. In particular,
            the double integrator system was illustrated in detail, since it will result from
            applying a preliminary nonlinear feedback on mechanical manipulators. In
            Chapter 3, we introduce the dynamical description of rigid robot



            Copyright © 2004 by Marcel Dekker, Inc.
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