Analysis and optimization of tendinous actuation for biomorphically designed robotic systems

We present a general framework for modeling a class of mechanical systems f or robotic manipulation, consisting of articulated limbs with redundant ten dinous actuation and unilateral constraints. Such systems, that include bio morphically designed devices, are regarded as a collection of rigid bodies, inter-acting through connections that model both joints and contacts with virtual springs. Methods previously developed for the analysis of force dis tribution in multiple whole-limb manipulation are generalized to this broad er class of mechanisms, and are shown to provide a basis for the control of co-contraction and internal forces that guarantee proper operation of the system. In particular, in the presence of constraints such as those due to limited friction between surfaces or object fragility, the choice of tendon tensions is crucial to the success of manipulation. An algorithm is descri bed that allows to evaluate efficiently setpoints for the control of tendon actuators that "optimally" points for the control of tendon actuators that "optimally" (in a sense to be described) comply with the given constraints .