Simulation of contact dynamics of flexible multi-body systems

Abstract

A detailed modelling of contact dynamics of general flexible multi-body systems of arbitrary kinematic architecture is considered in the paper. The components undergoing direct contact (e.g., the endeffector of the manipulator and the grapple surface) are modelled using a finite element method that incorporates large rigid body displacements, while the rest of the system is handled through the usual flexible multi-body formulation. The basic condition of the contact is that no material overlap can occur; this condition is expressed in terms of a set of algebraic constraint equations. The different multi-body systems in turn are related by kinematic constraint equations. Thus the system dynamics is described by sets of differential equations (either multi-body formulations or finite element nodal displacement formulations of the contacting surfaces) subjected to sets of algebraic equations expressing kinematic or contact constraints. A procedure to solve this system of equations is proposed in the paper. A typical scenario involving capture of a multi-body flexible satellite system using a spacecraft-mou nted manipulator is considered and computer simulation results are presented.