中文摘要：

交通事故和中风后的神经损伤会导致下肢伤残，使得患者无法完成抬脚之类的简单动作。为了帮助患者恢复运动能力，提出一种适用于脚踝康复的3自由度绳驱动并联机构。首先介绍了绳驱动踝关节康复机构的结构。其次利用牛顿－拉夫逊迭代法和封闭矢量环法计算了位姿正反解，建立了速度雅可比矩阵。通过对驱动绳索的张力进行分析，优化了张力分布并求解了机构的工作空间。最后，基于雅可比矩阵分析了机构的运动性能。结果表明在规定的工作空间内机构无奇异点，有良好的运动灵巧性和刚度性能。而且设计的等效球面副和动平台使得机构的转动中心较好地与踝关节的转动中心相重合，相比现存的踝关节康复机器人更具优势。综上，设计的机构适合脚踝康复训练。

英文摘要：

Neurological impairment after stroke or traffic accident can lead to the disability of lower limbs and the inability of simple actions such as foot lifting. In order to recover the motion ability of the patients, a 3DoF （degree of freedom） cable-driven parallel mechanism is proposed for ankle rehabilitation. Firstly, the structure of the cable-driven parallel mechanism for ankle rehabilitation is introduced. Then, the forward and inverse kinematics are solved by using the Newton-Raphson iteration method and the closed-vector-circle method, and the velocity Jacobian matrix is established. By analyzing the driving force of each cable, tension distribution is optimized and the workspace of the mechanism is calculated. Lastly, kinematical performances are analyzed based on the Jacobian matrix. Results show that the mechanism is of no singularity, good kinematic dexterity and stiffness performance within the prescribed workspace. Furthermore, the mechanism center of rotations matches accurately with the ankle center of rotations owing to the equivalent spherical pair and the moving platform designed in this paper, which is an advantage over some existing ankle rehabilitation robots. The designed mechanism is suitable for ankle rehabilitation training.