基于双环结构的视觉伺服云台控制器设计

Visual servo platform controller design based on double-loop structure

针对二自由度视觉伺服云台中相机低采样率的缺陷,基于角度与像素之间的转换关系,提出了一种双环结构的控制方案。在角度环控制器设计中,将满足LQ最优准则的扩展状态反馈与状态观测器设计整合为一个H2设计问题,并增加了可调参数k,兼顾了角度环的响应速度与超调量;在图像环控制器设计中,通过辨识获得了相机的动态特性,给出了图像环PI控制器参数整定原则。该设计方法在实际系统上取得了较好的伺服效果,对快速性和超调量要求高的控制器设计有一定的指导作用。

In the two-DOF vision servo platform,aiming at the defect of low sampling rate of camera,this paper proposed a double-loop control scheme based on the conversion between angle and pixel. In the design of angle-loop controller,this scheme integrated the extended state feedback and state observer design into a H2 design problem,which satisfied the LQ optimal criterion. In order to accelerate the response and reduce the overshoot of angle loop,it added adjustable parameter k. In the design of the image loop controller,this scheme obtained the dynamic characteristics of the camera by means of identification,and gave the parameter design principle of PI controller. The design scheme achieves good results in the actual system,and it has a certain guiding effect on the controller design which has high requirements to response and overshoot.