Passive Tension Adjustment of Tendon-Driven Mechanism for Drivability Improvement

In this paper, we propose a new method to improve the drivability of tendon-driven systems. There are three main conventional tendon drive methods: (1) using one actuator per joint, (2) using springs for pre-tensioning, and (3) using two actuators to move one joint. The proposed method extends (2) and aims to avoid the traditional drawback of a two-inertia system. First, we conducted experiments on the load's tracking performance relative to the motor and demonstrated the effectiveness of using adjustments, including the spring-type mechanism. Subsequently, we evaluated drivability by examining the ratio between the input and received torque, confirming that the two-inertia effect was reduced compared to that in the conventional spring-type mechanism.