Abstract：Parallel cable-driven exoskeletons for motion assistance have the advantages of good compatibility with the human body, large range of motion, and many degrees of freedom. However, it often requires multiple motors to drive multiple cables, increasing the weight and energy consumption of the actuator. In the previous design, it was impossible to reduce the number of motors while realizing the multi-cable force control and multi-degree-of-freedom assistance. This paper proposes an exoskeleton for shoulder joint assistance based on an underactuated parallel cable mechanism, utilizing cams and springs to realize the three-degree-of-freedom assistance of the shoulder joint. According to a given action of the arm, this research conducts kinematics modeling, static modeling, cable arrangement optimization and cam profile designing. As a result, only one motor is used to achieve the different output speeds required by multiple cables. The analysis and simulation of the relationship between the rotation angle of the motor and the force of each cable in accordance with the three-degree-of-freedom assisting relationship of the shoulder joint were done. Results show that the corresponding relationship between the motor rotation angle and the cable force is accurate, verifying the feasibility of the under-driven mechanism for multi-cable and multi-degree-of-freedom force control.
黎帆, 李东兴, 王殿君, 陈亚, 唐晓强. 基于欠驱动并联索机构的肩关节助力外骨骼[J]. 清华大学学报（自然科学版）, 2022, 62(1): 141-148.
LI Fan, LI Dongxing, WANG Dianjun, CHEN Ya, TANG Xiaoqiang. Exoskeleton for shoulder joint assistance based on underactuated parallel cable mechanism. Journal of Tsinghua University(Science and Technology), 2022, 62(1): 141-148.
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2022, Vol. 62 
