Experimental Research On Image Stabilization Of GM-APD Lidar Based On PID Control

In recent years,Gm-APD laser radar is widely used in various high-tech detection fields.Its imaging system platform is often interfered by various noises in the actual working process,which leads to unstable imaging of laser radar.Therefore,it is very necessary to study the image stabilization of the lidar imaging system.This paper studies the image stabilization system of laser radar based on PID control algorithm:Firstly,the theory of Gm-APD laser radar image stabilization is introduced.The structure and working mode of the laser radar image stabilization system are studied.The principle of PID control algorithm and the link selection and parameter adjustment method of PID algorithm are studied.The design indicators of the system are pointed out,and several common laser radar image sharpness evaluation methods are introduced.Secondly,the model of Gm-APD laser radar image stabilization control system is built.The transfer function calculation and optimization of the key components such as motor,motor driver and sensor in the control platform are carried out,and the double closed-loop control mode of speed and position loop is determined.The PI,PD and PID three commonly used PID control algorithms are used to simulate the system speed loop.The P controller is used to simulate the system position loop and the noise interference is added to the simulated image stabilization system.The characteristics of the three control algorithms are further compared and analyzed.At the same time,for the instability of the gyroscope output in the image stabilization system,the Allan variance method is used to quantify the gyroscope noise,and the real output data of the gyroscope is calculated by Kalman filter.The noise filtering is carried out.According to the characteristics that the noise covariance matrix is difficult to estimate in the Kalman filter algorithm,the improved adaptive Kalman filter is introduced to filter the real output of the gyroscope,and compared with the denoising effect of Kalman filter.Finally,the PID control algorithm and the gyro filtering algorithm are written into the DSP embedded platform.The PID tracking algorithm is tested for the tracking function.The algorithm parameters and parameters of the PID control are determined.The real Gm-APD laser radar image stabilization experiment was carried out,and sinusoidal vibration interference was applied to the laser radar imaging system.PID control,PID+Kalman filter control,PID+improved adaptive Kalman filter control are used to stabilize the image,and the image is drifted in real time during the image stabilization process.The analysis of the resolution of the number of pixels and the image of the most valued image,the image stabilization effects of the three image stabilization methods are compared and analyzed.The results show that the PID algorithm and the adaptive Kalman filter algorithm have a good image effect on stabilization of the lidar imaging system.