摘要
针对未知复杂工作环境下人机互助机械臂存在物理人机交互安全的问题,文中提出一种基于摩擦扰动补偿的机械臂碰撞检测方法。首先,基于牛顿-欧拉法建立机械臂动力学模型,推导动力学线性化回归重组模型,确定待辨识动力学参数;其次,优化设计机械臂激励轨迹,采集轨迹数据基于最小二乘法辨识动力学模型参数;再次,将摩擦力视为机械臂关节运动的扰动项,建立基于广义动量的2阶扰动观测器估计关节摩擦力,基于LuGre动摩擦模型和遗传算法表征系统摩擦特性,建立基于摩擦扰动补偿的外力矩观测器;最后,采集数据进行碰撞检测试验,试验结果表明:所提基于摩擦扰动补偿的机械臂碰撞检测方法检测精度较高,在不同未知工作环境下可有效提高人机协作的安全性。
Since the human-machine mutual assistance manipulator suffers physical human-machine interaction safety in un-known complex working environments,a method of collision detection is proposed based on friction disturbance compensation.Firstly,the manipulator’s dynamic model is set up with the help of the Newton-Euler method,and the dynamic linearized regres-sion recombination model is derived to work out the dynamic parameters to be identified.Secondly,the manipulator’s excitation trajectory is optimized,and the trajectory data is collected,so as to identify the dynamic model’s parameters by means of the least square method.Thirdly,the friction force is regarded as the disturbance term of the manipulator’s joint motion;the general-ized momentum is used to set up the second-order disturbance observer,in order to estimate the force exerted on the manipulator’s joint friction;both the LuGre dynamic friction model and the genetic algorithm are used to characterize the system’s friction characteristics,and thus the external torque observer is constructed based on friction disturbance compensation.Finally,the data is collected for test of collision detection.The results show that the method for the manipulator’s collision detection based on fric-tion disturbance compensation has high accuracy in detection and can effectively improve the safety of human-machine cooperation in different unknown working environments.
作者
吴灏
王淇锋
王其
冯驰
王鑫
赵健
WU Hao;WANG Qifeng;WANG Qi;FENG Chi;WANG Xin;ZHAO Jian(Shijiazhuang Power Supply Branch of State Grid Hebei Electric Power Co.,Ltd.,Shijiazhuang 050051;School of Mechanical Engineering,Hebei University of Technology,Tianjin 300401)
出处
《机械设计》
CSCD
北大核心
2024年第9期101-110,共10页
Journal of Machine Design
基金
国家电网有限公司总部科技项目(kj2021-020)。
关键词
人机互助机械臂
碰撞检测
扰动观测器
LuGre动摩擦模型
human-machine mutual assistance manipulator
collision detection
disturbance observer
LuGre dynamic fric-tion model