基于精准步态下肢康复机构的优化设计

Design and optimization of lower limb rehabilitation mechanism based on accurate gait

针对下肢瘫痪患者对精准步态康复的需求,文章设计了一种新型的单自由度坐姿下肢康复机构。通过运动学分析得出,提高M点运动轨迹与正常行走时踝关节运动轨迹的重合度可精准复现正常步行时髋关节和膝关节的运动规律;采用一种基于曲柄转角为设计变量的全局Powell优化方法,对下肢康复机的执行机构进行尺寸优化设计;取身高1604 mm的人体下肢尺寸进行仿真,实验结果表明,该机构能使髋、膝关节的角度误差控制在5°以内,在0.6~0.9 s区段关节的角位移与实际步态的重合度达到98%以上。该下肢康复训练机构驱动少、结构简单,能够满足患者在家庭和社区中对精准步态的康复需求。

In view of the accurate gait rehabilitation of patients with lower limb paralysis,a novel 1-DOF mechanism for sitting lower limb rehabilitation was designed.Through kinematics analysis,it is proved that to accurately reproduce the regularity of hip joint and knee joint movements during normal walking,we only need to control the movement trajectory of point M to completely match the trajectory of the ankle joint during normal walking.Therefore,a global Powell optimization method based on the design of the crank angle was used to optimize the actuator of the lower limb rehabilitation machine.The simulation on a human lower limb size of 1604 mm was made,and the experimental results show that the mechanism can control the angular error of hip and knee joints within 5°,and the degree of coincidence between the angular displacement of the joint and the actual gait in the range of 0.60.9 s is more than 98%.The lower limb rehabilitation training mechanism is less driven and has a simple structure,and can meet the patient’s demand for accurate gait rehabilitation at home and in the community.