Application of tension control into linear motor-actuated cable differential-driven joint

Tendon-driven systems are one of efficient methods to downsize robots. This paper discusses application of tension control into a joint using cable differential. Cable differential is mechanism which allows two-degrees of freedom (DOF) in one joint. Controllers for the cable differential-driven joint are proposed in the paper. The joint is actuated by four linear motors. The controllers are designed regarding the tendon-driven system as a redundant system. In this way, tension control is considered as a task in the null space. This makes implementation of tension control stereotypical.