A physically parallel one directional recursion (PPO-Recursion) for robot inverse dynamics

This paper proposes a novel physically parallel and one directional recursion (PPO-Recursion) for distributed recursive computation of the robot inverse dynamics. The algorithm differentiates between the different physical sources of torques/forces acting on the robot link centre of gravity or joint. Three completely parallel recursions for robot inverse dynamics computation that exploits the inertial, coupling and gravitational aspects of the robot mechanics are introduced. The recursions use the known Newton-Euler Formulation for the robot dynamics in a manner that sustains the recursion to be executed only in one direction (outward/forward). Thus, the necessity to use the outward (forward) together with the inward (backward) recursion is eliminated. Further, the one directional outward recursion is split according to the physical origin of the acting torques or forces. Beside computing the partial velocities and accelerations exerting due to their different physical origin, the proposed PPO-Recursion resembles the computation in a manner that reveals a high parallelism for distributed computing of the robot motion animation as well as its inverse dynamics