Improvement of Numerical Ill-posedness of Contact Force Computation in Forward Dynamics of Multibody based on Balanced Micro/Macro-Collision Model

Abstract

A contact force computation method in forward dynamics simulation of multibody systems is proposed based on a fusion technique of both the microscopic and the macroscopic contact models. The former models microscopic deformation of colliding objects, while the latter models macroscopic uncontinuous change of impulse. The difficulty of the contact dynamics simulation is mainly at numerical ill-posedness which is due to the coexistence of two phenomena with largely different durations. The proposed method resolves this problem by superposing the microscopic models to the macroscopic models in order to complement the drawbacks of each other. As the result, numerical stability, avoidance of chattering, recovery of excessive penetration of colliding objects and easy implementation of static friction model are simultaneously achieved.