基于机器视觉和改进PID的压电柔性机械臂振动控制

Piezoelectric flexible manipulator vibration control based on machine vision and improved PID

为解决振动主动控制系统中接触式测量影响结构特性以及PID控制参数整定不理想的问题,提出利用机器视觉技术测量结构振动,并结合人工鱼群算法优化的PID进行振动控制。首先,选择刚柔双关节机械臂作为研究对象,搭建实验平台并设计正交试验,探究刚柔耦合机械臂振动情况,并确定振动控制中电机参数的设置;其次,利用CCD相机采集机械臂末端标记点振动图像,并处理得到振动位移,将其作为控制系统输入;最后,选择人工鱼群算法对PID控制器参数进行优化,控制器输出信号经输出卡转化为控制电压,再经功率放大器放大,驱动压电作动片实现振动控制。实验结果表明,相较于传统参数整定PID平均44.06%的控制效果,优化后的PID算法平均控制效果可达到57.54%,验证了基于视觉测振的优化PID控制系统的可行性和优越性。

Considering the problem that the contact measurement influenced structure characteristics and the PID control parameter setting were not ideal in the vibration active control system,the machine vision technology was used to measure the vibration of the structure,and the vibration control was carried out with the PID optimized by artificial fish swarm algorithm.Rigid and flexible double-joint mechanical arm was selected as the research object.Firstly,the experimental platform was set up and the orthogonal test was designed to explore the vibration situation of rigid-flexible coupling mechanical arm and determine the motor setting parameters for subsequent vibration control;Secondly,CCD camera was used to capture the vibration image of the marker at the end of the mechanical arm,and the vibration displacement was obtained by processing and was used as the input of the control system.Finally,the artificial fish swarm algorithm was selected to optimize the PID parameters.The output signal of the controller was converted into control voltage by the output card.The control voltage was amplified by the power amplifier and drived the piezoelectric actuator to realize vibration control.The experimental results show that the average control effect of the optimized PID algorithm can reach 57.54%compared with the traditional PID control effect of 44.06%,which verifies the feasibility and superiority of the optimized PID control system based on visual vibration measurement.