ON THE SIMULATION AND CONTROL OF SOME FRICTION CONSTRAINED MOTIONS

In this paper, some issues involved with numerical simulation and cont rol of some elasto-dynamic systems are discussed. The motivation is th e simulation of dry or Coulomb friction in the joints that link togeth er remote manipulator systems used in aerospace operations (for exampl e, space shuttle remote manipulator systems). The goal here is to deve lop numerical techniques to simulate and control these systems, while properly modeling the Coulomb friction. The numerical procedure descri bed employs a finite difference time discretization in conjunction wit h a vector of multipliers that predicts the friction effect for all ti me. In addition to this discrete multiplier technique an associated re gularization procedure that greatly improves the behavior of these mul tipliers is also presented. Numerical examples conclude the paper.