An Analytical Solution for Spherical Joint Mechanism Including Coulomb Friction

This paper introduces the friction sphere concepts to consider the effects of friction in the spherical joint and presents a new effective numerical solution method for the analysis of multibody systems with spherical joint under Coulomb friction. Complete equations of motion and reaction forces are derived for dynamic analysis of multibody systems by using Lagrangian formulation.

The numerical solutions of the new method are illustrated by its applications to the variable displacement car air conditioning compressor, which has five pistons connected to the wobble plate by five actuating rods with spherical joints at both ends. The new method successively accomplishes the solutions of the equations of motion and reaction forces of the compressor in less computing time than the conventional method.