Partitioning of Recursive Multibody Dynamics

Minimal coordinate formulations provide the basis for the development of fast computational recursive methods for multibody dynamics. This paper studies the introduction of mass-less bodies to partition body \dofs between the original and the new mass-less bodies. Such partitioning offers computational advantages by reducing the size of the matrix/vector quantities in the recursive algorithms. In particular, we study the relationship between the \atbi forward dynamics algorithms for the unpartitioned and partitioned models of the system. We derive the relationship between the \atbi quantities, and identify the agreements at the body level for the recursions. We furthermore continue a similar study for the operational space inertia quantities for the unpartitioned and partitioned formulations and derive relationships between them.