摘要
针对传统骨外固定器矫形力无法准确控制、安全性差的问题,本文基于RCM构型,搭建一种膝关节骨外固定机器人,提出一种间接自适应阻抗的矫形力跟踪方法。由于存在机械摩擦以及外部不确定性,针对阻抗控制鲁棒性差的问题,采用力误差信号作为目标阻抗的驱动力,建立新的阻抗模型适应矫形环境的变化,根据矫形力误差的变化,设计自适应律对阻抗参数实时调节,在线补偿动态环境的不确定性,使系统的力跟踪误差为零。并对所提的控制算法进行了胫骨矫形力控制的对比仿真和样机实验。结果表明:阻抗控制仿真结果各性能指标的加权平均值分别为2.12、8.58和13.2,且力跟踪实验的最大误差为20 N;相比于阻抗控制,自适应阻抗控制仿真性能指标的加权平均值仅为0.36、0.18和0.61,力跟踪波动误差控制在±3 N以内,具有更好的鲁棒性和自适应能力。
To address the problem that the orthopedic force of the traditional bone external fixator cannot be accurately controlled and has poor safety,the article establishes a knee bone external fixation robot based on the RCM configuration and proposes an orthopedic force tracking control method with indirect adaptive impedance.Due to the existence of mechanical friction and external uncertainty,to address the problem of poor robustness of impedance control,the force error signal is adopted as the driving force of the target impedance,a new impedance model is formulated to adapt to the changes in the orthopedic environment.According to the changes in the contact force,the adaptive law is designed to regulate the impedance parameters in real time,which compensates for the uncertainty of the environmental dynamics on the line.Therefore,the system's force tracking error is zero.Comparative simulations and prototype experiments of the proposed control algorithm for tibial orthopedic force control are implemented.The results show that the impedance control simulation results of the weighted average of the performance indicators are 2.12,8.58 and 13.2,and the maximum error of the force tracking experiment is 20 N.Compared with impedance control,the weighted average of the performance indicators of adaptive impedance control simulation is only 0.36,0.18 and 0.61,and the force tracking fluctuation error is controlled to be within±3N,which has better robust and adaptive ability.
作者
苏鹏
谢实辉
刘霖
赵伟
张力
Su Peng;Xie Shihui;Liu Lin;Zhao Wei;Zhang Li(School of Mechanical and Electrical Engineering,Beijing Information Science and Technology University,Beijing 100192,China;Rehabilitation Hospital,National Research Center for Rehabilitation Technical Aids,Beijing 100176,China)
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2023年第11期99-108,共10页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(52005045)
中央级公益性科研院所基本科研业务费专项(102118170090010009001)
北京市自然科学基金-海淀原始创新联合基金(L192018)项目资助
关键词
骨外固定机器人
RCM机构
自适应阻抗控制
阻抗参数
矫形力跟踪控制
bone external fixation robot
RCM mechanism
adaptive impedance control
impedance parameters
force tracking control
