Analyzing and Optimizing Multibody Systems*

Optimization of holonomic as well as non-holonomic multi body systems is presented as a nonlinear programming problem that can be solved with general-purpose optimization codes. The adjoint variable approach is used for calculating design derivatives of a rather general integral type performance measure with respect to design parameters. The resulting equations are solved by numerical integration backward in time. A multistep integration algorithm with order and step-size control is adapted for this application by including an interpolation scheme. Numerical experiments and a comparison to the common approach of approximating the gradient of the performance measure by finite differences show that high efficiency, accuracy, and reliability are achievable. 'Communicated by E. J. Haug. 67 Copyright <!:l 1992 by Marcel Dekker, Inc. 68 BESTLE AND EBERHARD