Shi Ke, Song Aiguo, Li Ye, Li Huijun, Chen Dapeng, Zhu Lifeng
School of Instrument Science and Engineering, Southeast University, Nanjing, China.
Front Neurorobot. 2021 Apr 8;15:664062. doi: 10.3389/fnbot.2021.664062. eCollection 2021.
This paper developed a cable-driven three-degree-of-freedom (DOF) wrist rehabilitation exoskeleton actuated by the distributed active semi-active (DASA) system. Compared with the conventional cable-driven robots, the workspace of this robot is increased greatly by adding the rotating compensation mechanism and by optimizing the distribution of the cable attachment points. In the meanwhile, the efficiency of the cable tension is improved, and the parasitic force (the force acting on the joint along the limb) is reduced. Besides, in order to reduce the effects of compliant elements (e.g., cables or Bowden cables) between the actuators and output, and to improve the force bandwidth, we designed the DASA system composed of one geared DC motor and four magnetorheological (MR) clutches, which has low output inertia. A fast unbinding strategy is presented to ensure safety in abnormal conditions. A passive training algorithm and an assist-as-needed (AAN) algorithm were implemented to control the exoskeleton. Several experiments were conducted on both healthy and impaired subjects to test the performance and effectiveness of the proposed system for rehabilitation. The results show that the system can meet the needs of rehabilitation training for workspace and force-feedback, and provide efficient active and passive training.
本文研发了一种由分布式主动半主动（DASA）系统驱动的缆索驱动三自由度（DOF）手腕康复外骨骼。与传统的缆索驱动机器人相比，该机器人通过增加旋转补偿机构和优化缆索附着点的分布，极大地扩大了工作空间。同时，提高了缆索张力的效率，并减小了寄生力（沿肢体作用在关节上的力）。此外，为了减少致动器与输出之间的柔性元件（如缆索或鲍登缆索）的影响，并提高力带宽，我们设计了由一个带齿轮的直流电机和四个磁流变（MR）离合器组成的DASA系统，该系统具有低输出惯性。提出了一种快速解缆策略以确保在异常情况下的安全。实现了一种被动训练算法和按需辅助（AAN）算法来控制外骨骼。对健康受试者和受损受试者都进行了多项实验，以测试所提出的康复系统的性能和有效性。结果表明，该系统能够满足康复训练对工作空间和力反馈的需求，并提供高效的主动和被动训练。
