2-PPS∕PPR并联辅助起坐机构设计与分析  

Design and analysis of 2-PPS∕PPR parallel sit-to-stand assistive mechanism

作　　者：何鑫垚 罗国萍 徐陆蚰 王玉金 HE Xinyao;LUO Guoping;XU Luyou;WANG Yujin(School of Mechanical Engineering,Chongqing University of Technology,Chongqing 400054)

机构地区：[1]重庆理工大学机械工程学院,重庆400054

出　　处：《机械设计》2025年第3期39-47,共9页Journal of Machine Design

基　　金：国家自然科学基金面上项目(52275007);重庆市教委科学技术研究计划项目(KJQN202101131);重庆市科委自然科学基金面上项目(cstc2020jcyj-msxmX0242);重庆市教育委员会在渝高校与中科院所属院所合作项目(HZ2021011)。

摘　　要：为了助力下肢肌肉乏力患者,文中设计了一种并联式辅助起坐机构。采用Vicon运动捕捉系统获得起坐过程中的臀部运动轨迹,建立臀部位姿方程;再根据臀部位姿变化提出2-PPS∕PPR并联辅助起坐机构设计方案,采用旋量理论验证其自由度,并对机构进行运动学建模;然后,选择两种不同广义坐标推导机构的雅可比矩阵和灵巧度,并在尺寸约束条件下对比两种广义坐标对应的灵巧度,获得机构的最佳宽度尺寸和驱动方案,建立虚拟样机进行运动学仿真。结果表明:机构能够满足功能需求,该研究为后续的动力学分析、运动∕力控制奠定了基础,也为智能辅助轮椅的设计提供了参考。In this article,a parallel assistive mechanism is proposed to provide power-assisted sit-to-stand for people with lower-limb weakness.Firstly,the hip trajectory throughout the sit-to-stand process is recorded with the help of the Vicon motioncapturing device,in order to work out the equations of position and orientation.Secondly,the 2-PPS∕PPR parallel mechanism is configurated according to the changes in position and orientation.The parallel mechanism’s degree of freedom is verified through the screw theory,and the kinematics model is constructed.Thirdly,two categories of generalized coordinates are defined and employed to deduce the parallel mechanism’s Jacobian matrix and dexterity.Then,by comparing the dexterities corresponding to the two generalized coordinates with the dimension constraints,the optimal schemes are identified for the parallel mechanism’s width and driving.Finally,a virtual prototype is produced for kinematic simulation.The results demonstrate that this parallel mechanism meets the functional requirements.This study lays a solid foundation for subsequent kinematic analysis and motion∕force control,and provides reference for development of intelligent assistive wheelchairs.

关 键 词：辅助起坐机构 并联 运动学 性能分析 虚拟样机 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置]