WINCH-BASED AND CABLE-DRIVEN JOINT ACTUATOR WITH TWO-STAGE REDUCTION MECHANISM
Keywords:
Cable-driven actuator, Two-stage reduction, Winch-based reducer, Joint designAbstract
This paper presents a compact winch-based, cable-driven joint actuator with a two-stage reduction mechanism aimed at improving weight, backdrivability, and impact tolerance of robotic joints within constrained volumes. The design integrates primary and secondary reduction stages with an optimized winding scheme and an in-situ tensioning mechanism for stable transmission. A practical dual-encoder scheme provides an absolute output angle after power cycling. We detail the mechanical structure, winding/tensioning strategy, and electronics, and report measurements of reduction ratio, required pre-tension, and output stiffness. Experiments show a highly effective reduction ratio and predictable output stiffness consistent with modeling, with improved backdrivability under comparable size and mass. The module is suitable for compact legged/humanoid systems.References
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