牵引式下肢康复机器人机构参数优化及轨迹规划

为满足下肢运动功能障碍患者在不同阶段的康复训练需求，针对现有下肢康复机器人训练方式单一的问题，提出了一种可实现卧姿、坐姿训练模式的牵引式下肢康复机器人。首先，根据人体下肢运动机理和仿生原理，设计了一种五自由度混联机构构型。然后，建立了机器人的运动学模型，分别计算了其运动学正、逆解。接着，以人体下肢末端与机器人末端的工作空间重合度为目标函数，采用遗传算法对机器人的机构参数进行了优化，并求得人机系统矢状面内人体下肢的有效工作空间比为0.71。最后，规划了CPM（continuous passive motion，连续被动运动）、圆周运动和螺旋运动等3种康复训练运动轨迹，并根据优化后的机构参数搭建了机器人样机，通过运动捕捉实验验证了机器人结构设计与优化结果的合理性以及轨迹规划的正确性，表明该机器人能够满足下肢运动功能障碍患者的康复需求。

Mechanism parameter optimization and trajectory planning of traction lower limb rehabilitation robot

In order to meet the rehabilitation training needs of patients with lower limb motor dysfunction at different stages, a traction lower limb rehabilitation robot that could realize the training modes of lying and sitting postures was proposed in view of the single training mode of existing lower limb rehabilitation robots. Firstly, according to the motion mechanism and bionic principle of human lower limbs, a five-degree-of-freedom hybrid mechanism configuration was designed. Then, the kinematics model of the robot was established, and the forward and inverse kinematics solutions were calculated, respectively. Then, taking the workspace coincidence degree between the end of human lower limb and the end of robot as the objective function, the mechanism parameters of robot were optimized by the genetic algorithm, and the effective workspace ratio of human lower limb in the sagittal plane of the human-machine system was 0.71. Finally, three kinds of rehabilitation training trajectories including CPM (continuous passive motion), circular motion and spiral motion were planned, and a robot prototype was built according to the optimized mechanism parameters. Through motion capture experiments, the rationality of the robot structure design and optimization results and the correctness of trajectory planning were verified, which indicated that the robot could meet the rehabilitation needs of patients with lower limb motor dysfunction.