From Two-Dimensional to Three-Dimensional: Diversified Bending Modality of a Cable-Driven Actuator and Its Grasping Characteristics

Cable-driven actuators are widely studied and utilized in soft robotics, and cable-driven is a traditional, advanced, and practical driving method. While limited by the uniaxial force transfer of the driving cable in previous researches, the cable-driven actuator can only bend in a two-dimensional (2D) plane. To further expand their scope of utilization, a new design scheme of an actuator is proposed to realize the transition from 2D bending to three-dimensional motion. A zigzag cable routing (ZCR) mode is presented to improve the helical motion. Compared with the straight cable routing mode, the ZCR actuator has better smooth movement characteristics and expanded functionality. Furthermore, we experimentally investigated the contact force and holding ability. The results show that the contact force is evenly acting on the cylinder target, and the grab weight is greater than 1950 g.