Robot Acceleration Capability: the Actuation Eeciency Measure

This article presents a new performance measure, the actuation eeciency, which describes isotropy in acceleration capability for non-redundant manipulators. It measures the imbalance between the end-eeector accelerations achievable in diierent directions. Prior to this, no measure of this characteristic was adequate for a six degree-of-freedom manipulator, because its end-eeector motions are referenced to a mix of linear and angular coordinates. The proposed measure addresses both linear and angular accelerations. It also indicates oversized actuators, since this contributes to the imbalance in achievable accelerations. The development of this measure is based on the formulation of the motion isotropy hypersurface. The shape of this hypersurface is a weak indicator of acceleration isotropy.