基于DSP的斜轴式望远镜机架控制系统设计

Design of Oblique Axis Telescope Mount System Controller Based on DSP

摘要:

为了抑制望远镜驱动系统中的非线性干扰,设计了一种新型机架伺服控制系统；系统以45度斜轴机架转台为硬件平台,以DSP为主控制器,采用HQ7620摄像头模块进行位置反馈；首先DSP对图像模块采集的图像进行实时处理,得到目标图像质心的位置,并计算出该位置相对于视场中心的误差,接着对误差进行粒子群模糊PID控制,最后DSP的EV模块产生相应的PWM对机架驱动电机进行控制,实现对机架的高精度闭环控制；PWM波的频率设为10 kHz；实验数据表明:与模糊PID控制和PID控制相比,系统粒子群模糊PID控制下水平与竖直方向的误差均值为0.323 2像素,大幅度地提高了控制的稳定性,满足实际要求。

Abstract:

In order to control the nonlinear disturbance in a telescope control system, a new type mount servo control system is designed. It uses the 45 degree oblique mount as the hardware platform, DSP as the main controller and HQ7620 as the image capture. Firstly, DSP processes the images taken by HQ7620 real time, then calculates the centroid and its error to the center of view center. Secondly, the error is controlled by the particle swarm fuzzy-PID algorithm. Finally, DSP’s EV module generates PWM to control the mount’s drive motor, so that system is a closed-loop control system. The experimental data shows that the target is tracked and pointed continuously, and the precision meets the requirements.