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 multibody system is briefly discussed. The method is then used to perform 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, the Hamiltonian equations perform considerably better when using an adaptive method. This is at least the case when the error control is applied straightforwardly. Both methods can be made equally efficient by removing the error control on the velocities for the acceleration based equations