Base-invariant symmetric dynamics of free-flying manipulators

The freedom of choice in designating a base-body for free-flying manipulators gives these manipulators a base-invariance symmetry that is not encountered in fixed-base manipulators. This paper analyzes the relationship between this natural symmetry and the dynamical equations for free-flying manipulators. The base-invariance symmetry is used to develop a new formulation of the manipulator dynamics in which two independent O(N) recursions proceeding in opposite directions are summed together to obtain the complete free-flying manipulator dynamics. Computation of the operational space inertia for the links in the manipulator is also discussed