Research On Combined Tracking And Aiming Ranging System Based On PSD

Optoelectronic tracking and aiming technology are developing rapidly in the military and aerospace industries.Fast position tracking and aiming control dynamic target provides effective technical means and research development direction for achieving accurate target tracking.How to keep the laser to achieve stable tracking and aiming,so that the laser beam has anti jitter,small measurement error,and accurate ranging function has become the difficulty of this thesis.In view of these problems,this thesis designs the laser pointing stable control optical path to solve the position error of the outgoing beam;corrects the nonlinear distortion of the position sensitive detector(PSD)to reduce the measurement error;studies the fuzzy adaptive PID controller to realize the stable tracking of the tracking target in the presence of disturbance;the designed four-way phase-shifting interference structure can meet the requirements of the system,and the target achieves the requirement of continuous and stable ranging.In this thesis,the three components of the combined tracking and pointing ranging system are analyzed in detail.Firstly,the optical path of tracking and aiming measurement is studied.The simulation model of tracking and aiming optical path is established by optimizing function to represent the change of light spot on PSD photosensitive surface in tracking and aiming measurement system.The influence of two-dimensional mirror rotation on the shape of imaging light spot is studied by Zemax simulation.The factors influencing the light spot distortion are analyzed and the optimization method of the model is proposed.Then,based on the principle of optical autocollimation,an improved tracking and aiming optical path is designed,and a three-step turn back optical path is added to the system to reduce the total length of the measurement system.At the same time,the angle of the two-dimensional tracking mirror turntable is tested,and the error of the two-dimensional angle measurement is corrected and analyzed.The experimental results show that the angle error is controlled within 2 ",the error is reduced by more than 15%,and the linearity is greatly improved.It is verified that the autocollimation angle measurement method used in this system can be applied to the angle measurement of the two-dimensional mirror,so as to achieve the accuracy of the target track.The results show that the cubic spline interpolation algorithm proposed in this thesis has a good effect on PSD nonlinear distortion correction,reduces the angle average error,and meets the requirements of the measurement system for tracking accuracy.Secondly,the beam pointing stability control part is analyzed.The structure model of fast mirror(FSM)is established,and the transfer functions of input voltage and output angle are obtained.According to the transfer functions,the Simulink simulation model of fuzzy adaptive PID controller system is established,and the parameters are adjusted online,so that the fast mirror action output has better dynamic and static performance.The analysis shows that the adaptive fuzzy PID controller can make the fast mirror have good tracking ability for different disturbed targets.Aiming at the shortcomings of single FSM optical path system,a dual FSM laser beam stabilization system is constructed.The deflection of incident beam and the deflection error of outgoing beam are analyzed.It shows that the beam pointing stabilization optical path based on dual FSM can compensate the error caused by beam jitter,and then improve the pointing accuracy of the tracking system.Finally,the optical path of laser interference ranging is designed.The structure of laser interferometric ranging is designed by four-way phase-shifting interferometry.The displacement information of the target is obtained by the interference phenomenon of the beam.The interference fringe image is obtained by Zemax simulation.The interference fringe counter is designed and the Proteus circuit simulation is carried out.The target displacement ranging function is realized by counting the light and dark change process of the fringe.