Joint actuation switching in closed-chain mechanisms for high task adaptability

Presents the smooth joint actuation switching in a closed chain mechanism for achieving high task adaptability. First, the kinematic characteristics of a closed-chain mechanism possibly with actuational redundancy is formulated, and the effect of the distribution of actuating joints is analyzed. Next, with respect to the task compatibility in control efficiency or accuracy, the joint actuation switching of a closed-chain mechanism is optimized, and the discontinuity in joint torque incurred due to the abrupt joint actuation switching is described. Then, the smooth transition in joint actuation of a closed-chain mechanism is proposed, based on the redundancy resolution associated with the augmented statics defined for a short transition interval. Simulation results for a planar closed-chain mechanism are given