The application of the inertial parameter regrouping method to the robot forward dynamics algorithm

The authors describe how to apply the inertial parameter regrouping method to increase the efficiency of two widely used forward dynamics algorithms, R. Featherstone´s (1983) articulated-body inertia algorithm and M.W. Walker and D.E. Orin´s (1982) composite body algorithm. It is shown that the inertial parameter regrouping method can be applied to the articulated-body inertia algorithm by simply replacing the original spatial inertia matrices with new ones consisting of the regrouped inertial parameters. In addition, M. Gautier and W. Khalil´s (1988) regrouping method is used to reformulate the composite body algorithm in a more computationally efficient form. Examples are presented which show that the proposed algorithms considerably reduce the number of operations