Abstract: To make the robot joint with active stiffness characteristics,based on the controllable stiffness characteristics of Magneto-Rheological Fluid (MRF),a new robotic compliant joint was designed,and a dynamic torque tracking control of MRF compliant joint based on fractional-order PID control algorithm was proposed.Under the ideal Bode transfer function state,the method of frequency domain was used to derive the parameters of fractional-order PID controller through the desired cutoff frequency and phase margin,and a closed-loop control system based on fractional-order PID algorithm was established.An experimental system based on LabVIEW graphical programming language was established,and the dynamic torque tracking control experiments were carried out respectively based on fractional-order PID algorithm and integer-order PID algorithm.The experimental results clearly demonstrated that the fractional-order PID algorithm could achieve predictable behaviors of dynamic torque tracking control of MRF compliant joint.

Key words: magneto-rheological fluid, robotic compliant joint, fractional-order PID, dynamic torque tracking control

摘要： 为了使机器人关节具备主动变刚度特性,基于磁流变液的可控流变特性设计了一种新型机器人柔顺关节,并提出基于分数阶PID(PIλDμ)控制算法进行磁流变液柔顺关节的动态扭矩跟踪控制,采用频域设计方法,通过期望截止频率和相位裕量推导出理想Bode传递函数状态下的PIλDμ控制器设计参数,建立了基于PIλDμ的控制系统。设计了磁流变液柔顺关节实验平台,并且基于LabVIEW图形化编程语言开发了控制软件系统,分别进行了基于PIλDμ和整数阶PID动态扭矩跟踪控制实验,实验结果证明,PIλDμ控制算法对基于磁流变液设计的机器人柔顺关节具有较好的动态扭矩跟踪控制作用。

关键词: 磁流变液, 机器人柔顺关节, PID, 动态扭矩跟踪控制