直交・不交差軸を有する鞍関節式柔剛切替え線状メカニズム

―ジョイント半径に非依存の保持トルク定量評価―

抄録

Variable stiffness mechanisms in multi-joint structures face a challenge with their high weight-to-holding-force ratio. To achieve a higher holding force, increasing the joint radius is a common approach. However, this elevates the moment caused by self-weight at the structure's base. To address this issue, this study introduces a novel approach that allows for determining distinct distances from the center of rotation to both the joint radius and the holding torque. We concentrate on the saddle joint, characterized by two orthogonal, non-intersecting axes, to minimize joint radius while extending the distance to the holding torque's rotation center. By employing a saddle joint and wire, we evaluated the holding torque with the distance to the torque's rotation center exceeding the joint radius. Our findings demonstrate that the holding torque remains unaffected by the joint radius, offering a promising direction for enhancing multi-joint mechanisms' efficiency.