THE EFFECT OF FRICTION ON MULTIBODY DYNAMICS

This paper discusses the nature of frictional effects on multibody dyn amics and the influence of the effects on the numerical analysis of sy stems with friction. The joints in a multibody system are modelled as nonideal (friction-affected) constraints, and a general and easy manip ulation method of the mathematical modelling of the problem in absolut e variables is proposed. The governing equations arising are highly no nlinear differential-algebraic equations (DAEs). Two approaches to the numerical solution of the equations are discussed: using the DAE solv ers directly and introducing a symbolic-numerical procedure of convert ing the DAEs into a smaller set of equations. Some variant formulation s of the governing equations concerning the two approaches are demonst rated and discussed. The theoretical considerations are illustrated by a simple example.