基于单自由度Watt机构的拟人步态下肢康复机器人设计  

Design of an 1-DOF lower limb rehabilitation robot with humanoid gait based on Watt mechanism

作　　者：赵萍[1] 宋词 鲍紫怡 宋皖兵 康甜 黄德 ZHAO Ping;SONG Ci;BAO Ziyi;SONG Wanbing;KANG Tian;HUANG De(School of Mechanical Engineering,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]合肥工业大学机械工程学院,安徽合肥230009

出　　处：《合肥工业大学学报（自然科学版）》2022年第9期1153-1159,共7页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学基金资助项目(51775155)。

摘　　要：针对目前大多数下肢康复机器人结构复杂、造价高昂、控制不便等问题,文章优化设计出一款Watt-I型六杆机构式单自由度拟人步态下肢康复机构。对下肢康复机构进行尺度优化设计,以正常步态轨迹为目标轨迹对Watt-I型六杆机构进行轨迹综合,得到机构尺寸;对下肢康复机构进行轻量化设计,在SolidWorks中建立其三维模型,并导入到ANSYS Workbench中进行拓扑优化,得到优化后的简化模型;采用响应面方法对连杆板厚及边长等参数进行优化设计;基于优化后的机构对下肢康复机器人进行结构设计,给出三维模型。结果表明:该机构能很好地复现正常步态轨迹,目标轨迹点与对应机构轨迹点之间的平均位置误差仅为7.76 mm;在满足材料强度的条件下,轻量化后的六杆机构质量减少32.66%。该下肢康复机器人仅需一个匀速驱动即可为下肢运动障碍患者进行步行康复训练,具有普惠性。At present,most of lower limb rehabilitation robots are facing the problems such as complex structure,high cost and inconvenient control.In this paper,an one-degree-of-freedom(1-DOF)lower limb rehabilitation mechanism with humanoid gait based on Watt-I six-bar mechanism is optimally designed.First,the dimension of the lower limb rehabilitation mechanism is optimized.Taking the normal gait trajectory as the target trajectory,the path synthesis of Watt-I six-bar mechanism is carried out and the mechanism size is obtained.Then,the lightweight design of the lower limb rehabilitation mechanism is implemented.A three-dimensional model is established in SolidWorks,which is imported into ANSYS Workbench for topology optimization,and then a simplified model is obtained.After that,the parameters such as the thickness and side length of linkages are optimized based on response surface method.Finally,the structure of the lower limb rehabilitation robot is designed based on this optimized mechanism and its three-dimensional model is presented.The results show that the average position error between the target trajectory points and the corresponding mechanism trajectory points is 7.76 mm,so the mechanism can reproduce the normal gait trajectory very well;under the condition of meeting the material strength,the weight of the six-bar mechanism is reduced by 32.66%after lightweight design.The lower limb rehabilitation robot only needs a uniform drive to carry out walking rehabilitation training for patients with lower limb dyskinesia,which is generalized preferential.

关 键 词：下肢康复机器人 六杆机构 单自由度 步态轨迹 优化设计 轻量化 

分 类 号：TH112.1[机械工程—机械设计及理论]