Recursive Algorithm Based on Canonical Momenta for Forward Dynamics of Multibody Systems: Numerical Results

In this paper, a recursive O(n) method to obtain a set of Hamiltonian equations for open-loop and constrained multi body system is briefly discussed. The method is then used to perfor m a numerical comparison of acceleration based and canonical momenta based equations of motion. A relatively simple exam - ple consisting of a biped during double support phase is used for that purpose. While no significant difference in efficiency is found when using a fixed step numerical integration method, t he Hamiltonian equations perform considerably better when us ing an adaptive method. This is at least the case when the error control is applied straightforwardly. Both methods can be m ade equally efficient by removing the error control on the veloci ties for the acceleration based equations.