机器人液压旋转关节低速运动机理及实验

Mechanism and Experiment of Low-speed Motion of Robot Hydraulic Rotary Joint

针对机器人液压旋转关节的死区和低速爬行,研究其产生机理并进行了实验分析。首先,论述了密封摩擦的机理,计算摆动缸各种密封机构的摩擦力矩,构建低速状态下的摩擦模型;然后,利用数值分析方法对电液位置伺服系统建模,对低速爬行现象进行仿真分析;最后,通过实验对死区和爬行现象进行验证和分析,并观察PID控制对爬行现象的改善作用。仿真和实验结果表明:在密封元件的摩擦下,液压摆动缸存在较大死区,且低速运行时,液压摆动缸出现明显爬行现象,在PID控制器下可良好的改善跟踪响应。

Aimed at the dead zone and low-speed crawling of robot hydraulic rotary joints,the mechanism of their generation was studied and experimental analysis was conducted.Firstly,the mechanism of seal friction was discussed,the friction torque of various sealing mechanisms of the swing cylinder was calculated,and a friction model at low speed was constructed.Then,the electro-hydraulic position servo system is modeled by numerical analysis,and the simulation of low-speed crawling phenomenon is carried out.Finally,the dead zone and crawling phenomenon are verified and analyzed by experiments,and the effect of PID control on crawling phenomenon is observed.Simulation and experimental results show that under the friction of the seal element,there is a large dead zone in the hydraulic swing cylinder,and when the low-speed operation occurs,the hydraulic swing cylinder has obvious crawling phenomenon,which can improve the tracking response well under the PID controller.