Research On Vehicle Laser Communication Servo Control System

Wireless laser communication has the advantages of high speed and good confidentiality.In this paper,the vehicle laser communication servo control system is studied in depth based on the background of vehicle laser communication.The influence of atmospheric environment and vehicle mast vibration on the performance of laser communication acquisition,alignment and tracking system(APT)is analyzed,and the laser wavelength of vehicle communication is determined.The stability accuracy index of vehicle laser communication system is determined by analyzing the factors affecting the stability accuracy of servo system.Vehicle laser communication system uses GPS/INS for initial pointing,and analyses the scanning time and acquisition probability of the system.Aiming at the high precision characteristic of servo control system,a servo controller which integrates "DSP controller + SA60 motor driver + ST16C654 information acquisition" is designed.The structure and system structure of the vehicle turntable are introduced,and then the components of the system are analyzed and modeled.The transfer function of the vehicle turntable is identified in detail,and the identified model is verified.Finally,the speed loop and position loop controller of the servo system are designed.Aiming at the influence of FOG output signal error and noise on LOS stabilization loop,the error is calibrated and compensated.Two kinds of filtering methods for FOG output signal are studied: sliding filtering and Butterworth filtering.Comparing the filtering results,Butterworth filtering method is the best method.Finally,the gyro FOS stabilization loop is designed.In order to improve the anti-disturbance ability of the servo system,a speed disturbance observer is introduced into the control system based on the accurate system model.The experimental results show that the method can improve the stability accuracy of the servo system.The stability accuracy is tested indoors,and the vibration of vehicle turntable is simulated.Parallel light tube is used instead of beacon light.The stability accuracy is less than 60 urad.Establishing a 1Km laser communication link in the school,swinging the optical terminal on the swing table,the system stability accuracy is better than the design index 150 uard,can establish a stable laser communication link,the communication rate is about 1Mbps.