Font Size: a A A

Research On Line-of-sight Disturbance Rejection Method Of Airborne Photoelectric Stabilized Pod

Posted on:2021-02-24Degree:MasterType:Thesis
Country:ChinaCandidate:S Q ZhaoFull Text:PDF
GTID:2392330611996585Subject:Engineering
Abstract/Summary:PDF Full Text Request
As an equipment that integrating optical,automatic control,precision machinery,image acquisition and processing and other advanced technologies,airborne photoelectric stabilized pod is widely used in the military and civil fields for target detection,reconnaissance,targeting and tracking.During the operation of the pod,various disturbances from the aircraft carrier and the interior of the pod will affect the stability of the pod's line of sight(LOS),which will seriously affect the working effect of the photoelectric detection equipment.Therefore,it is of great significance to explore and research how to improve the disturbance suppression ability of the pod's LOS.In order to improve the dynamic response characteristics and disturbance rejection capability of the two-axis and two-frame photoelectric stabilized pod,conduct a series of researches in this paper,including:1)The photoelectric stabilized pod is systematically analyzed,including: the principle of pod isolation carrier angular motion,the composition of the pod system,the working mode and the composition and working principle of the servo control system under different working modes,and analyze the disturbance factors affecting the stability of pod LOS.Establish the model of the pod velocity control loop based on mechanism modeling method.Conduct the frequency sweeping experiment of the pod,and the acquired frequency sweeping experiment data are used to establish the approximate transfer function of the azimuth frame of the pod through the method of system identification.2)Linear Active Disturbance Rejection Control(LADRC)is applied to velocity loop of photoelectric stabilized pod servo system,then improve and optimize LADRC based on pod model that is established.The improvement and optimization include: firstly,derive the formula of model-assisted reduced-order linear extended state observer(abbreviate MRLESO)which is used to replace the linear extended state observer(LESO),and its convergence is analyzed.Secondly,in the control law,the observer's observation and estimation of the differential of the system's output velocity signal are replaced by the differential of system's output velocity signal.A lot of simulation experiments are conducted and analyzed to verify that the improved and optimized controller based on LADRC can improve the dynamic response characteristics and model perturbation robustness of the pod and the LOS disturbance rejection ability of the pod.3)Design and code the program of pod velocity loop control algorithm.Conduct the experiment of azimuth frame step response of the photoelectric stabilized pod and the experiment of LOS disturbance rejection based on improved LADRC(abbreviate ILADRC)and LADRC,the experimental results show that the ILADRC improved the dynamic response and disturbance rejection capability of the pod compare with the LADRC.
Keywords/Search Tags:airborne photoelectric stabilized pod, LOS disturbance rejection, Linear Active Disturbance Rejection Control, model assisted, reduced order linear extended state observer, control law
PDF Full Text Request
Related items