Design And Research On Photoelectric Tracking And Measuring Device For UAV Flight Performance Test

In this paper,an optical tracking measurement device for UAV flight performance testing is developed.As a high-precision automatic tracking device,the pointing accuracy and tracking control accuracy of the optical tracking measuring device affect the accuracy of the target tracking measurement.Therefore,in this paper,based on the structure design of the photoelectric tracking measurement device,the pointing accuracy and tracking control are studied and analyzed.Firstly,the overall structure design of the photoelectric tracking and measuring device is completed.According to the relevant technical requirements,the optical system selection of the device is completed,the structure scheme and drive scheme are determined,and the design of the vertical and horizontal axis systems are introduced in detail.By using finite element simulation software,the static and modal simulation analysis of key components and the whole machine of the photoelectric tracking and measuring device are carried out,and the stiffness and strength are verified to meet the requirements of application.The accuracy of the finite element model is verified by conducting inherent frequency test experiments on the tracking turntable.Next,the analysis of the pointing accuracy of the photoelectric tracking measurement device is studied.The error sources of the pointing accuracy of the device are analyzed,and the formula of the influence of the three-axis error on the pointing error is derived.The error transfer model of the pointing error is established by the coordinate transformation method,and the effect of each single error on the pointing error is simulated and analyzed.According to the analysis results,the orientation difference g,the deflection errorγ_c of the horizontal axis around the vertical axis coordinate system Z_c axis and the deflection errorγ_s of the visual axis around the horizontal axis coordinate system Z_s axis have a greater influence on azimuth pointing accuracy;the zero position difference h and the deflection errorβ_s of the visual axis around the horizontal axis coordinate system Y_s axis have a greater influence on the pitch pointing accuracy.After that,the rotation error of the horizontal and vertical axis systems of the device and the average axis verticality error of the two axis systems are tested and experimented,and according to the data analysis results,it is known that the axis system error meets the design requirements.Finally,the tracking control study of the photoelectric tracking and measurement device is carried out.The dynamics modeling of the photoelectric tracking and measuring device is carried out.For the problem of coupling between two axes and complex interference during the operation of the photoelectric tracking and measuring device,the backstepping sliding mode control algorithm is designed as an example for the azimuthal drive system.The performance of the designed backstepping sliding mode control algorithm is greatly improved compared with that of the PID control algorithm and the backstepping control algorithm,in which the step tracking response speed is improved by more than 21%,the steady-state accuracy of sinusoidal tracking and the steady-state accuracy under random disturbance are both improved by two orders of magnitude,and the stabilization time of pulse disturbance is reduced by more than 0.7s.After that,the two-axis motion of the photoelectric tracking and measurement device is simulated and analyzed to verify the effectiveness of the algorithm.