Research On The Measurement And Calibration System Of Projectile Roll Angle Based On PSD

Semi-active laser terminal correction projectile has become a research hotspot in recent years because of its advantages of high accuracy,simple structure and capacity of resisting disturbance.The operational principle is to start the control of the duck rudder under the specific rolling angle of the projectile to achieve the purpose of correcting the attitude of the projectile.The rolling angle is the key to realize real-time and accurate attitude control of projectile.Therefore,this paper focuses on the calculation and calibration system of projectile rolling angle based on position sensitive detector.This paper mainly includes the following aspects:The rolling angle calculation model based on position sensitive detector and the reference direction calibration model based on geomagnetic sensor were established.The system based on the laser sensor and the system based on the geomagnetic sensor calibration were carried out respectively considering the application platform,working environment and parameter requirements of the system.The noise model of amplifier circuit under the narrow pulse laser irradiation was established and the effect of frequency on the output voltage noise was introduced to improve the resolution of the circuit.The large dynamic range photocurrent was amplified by the AGC circuit according to the gain control strategy and the peak value of pulse signal was detected by the peak detection circuit.The A/D chip configuration and data reading were realized by the state machine of FPGA,the coordinate solving model and the UART model were also established to realize the solution and transmission of the incident spot coordinates.The hardware signal processing module,calculation module and data storage module were designed for the reference direction calibration system of projectile rolling angle.The multi-feedback band pass filter and Schmidt flip-flop were constructed to optimize the noisy geomagnetic signal,and the reference direction of the projectile rolling angle was calibrated by the timer capture function of ARM microprocessor.At last,the experiment of the ground calibration system was designed,and the static and dynamic measurement experiment of the rolling angle calculation system was carried out.Experiments show the calculation and calibration system has better stability and precision.