| In order to fulfill technical requirements of seekers of guided munitions,this dissertation mainly studied the effect of disturbance rejection rate(DRR)of different sorts of seeker to guidance stability and performance,the online identification and inhibition technique of DRR.This paper analysis the causes of DRR and derive its transfer function at the beginning of each chapter.And then,the stability of guidance system with different DRR models was analyzed;the effects of DRR on the time-domain characters of the control system and the effective proportional navigation coefficient were studied;furthermore,the miss distance was analyzed with inputs of different error sources.At the end of every chapter,the online estimation and inhibition technology is proposed using suitable filter algorithm.This paper firstly studies the generation mechanisms of DRR with strapdown seeker were systematically and discusses the effects on guidance performance of DRR by different inducemets,i.e.,the different scale factors between detector and angular rate gyro,dynamics mismatch of the two sensors.tem with DRRPL were analyzed.The miss distance casued by three different input error sources was studied by adjoint method,i.e.,initial velocity direction error,seeker zero error,and angular noise.angular noise.The research provide theoretical references to the guidance and control system design of strapdown guided munitions.Furthermore,the arithmetic using UKF was designed according to DDR caused by scale factor error.Moreover,the method based on matching filter was deduced to make a uniform dynamic of two sensors.Simulation results showed that the effect of DRR toguidance system could be reduced and the guidance accuracy couldbe enhanced by using these algorithms.Secondly,establishing a model of semi-strapdown imaging seeker's guidance system which contained disturbance rejection rate parasitic loop(DRRPL)which caused by scale error and disturbance torque.Analyze the effect of DRR on guidance accuracy under different input error source,i.e.,angular noise,Target maneuver.Then,proposing an online rejection method based on Strong Tracking Unscented Kalman Filter(STUKF)to solve the problem above.Result of numerical simulations illustrate that the STUKF algorithm can overcome the difficulty to accurately establish the disturbance torque model accurately,estimate DRR and real line of sight rate under the change of scale factors.Thirdly,analyzing strapdown phased array radar seeker DRR and establishing the its models based on seeker's working principles.The influence of different DRR models on guidance system performance is comparatively analyzed,and the online compensation method based on multiple model(MM)for strapdown phased array radar seeker DRR is proposed.The research results show that beam direction error and radome error slope are the main DRR factors which have a strong and similar impact on missile guidance system stability and guidance accuracy.Furthermore the influence of positive feedback of parasitic loop is more serious.The DRR caused by beam direction error and radome error slope can be compensated as a whole by the proposed online compensation method,which can greatly improve the overall guidance performance.Finally,DRR models of platform radar seeker considering radome error are established,and the influence of different DRR models on guidance system stability and guidance accuracy is comparatively analyzed.To compensate for the effect of DRR an online compensation method using STUKF is proposed.Performance analysis shows that positive radome error slope has small influence on guidance performance,while the influence of spring torque and damping torque is relatively larger.Additionally the influence of negative radome error slope is the most serious one.With the help of proposed STUKF based online compensation method,the DRR of platform radar seeker can be inhibited effectively and the performance of guidance system is improved.Compared to UKF,the STUKF algorithm has higher estimation accuracy.The results of this paper has a great significance bothon theory and on practical implication,and can provide theoretical guidance for the DRR online estimation and inhibition and the overall design of the guidance system. |
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