Research on the Influence of the Parasitic Loop of the Roll-Pitch Seeker on the Stability of the Guidance System

Disturbance rejection rate is an important performance index of the seeker,the disturbance rejection rate affects the extraction accuracy of the line-of-sight angular velocity output by the seeker,and introduce an additional parasitic loop in the guidance loop,this loop affects the stability of the guidance system and reduces the accuracy of the missile guidance system. This paper analyzes the extraction principle of the line-of-sight angular velocity of the roll-pitch seeker,the parasitic loop model of the roll-pitch seeker caused by the scale deviation between the detector, the frame angle sensor and the angular rate gyroscope is established, and the stability and time domain response characteristics of the parasitic loop are analyzed. Then, based on the time-invariant theory, the influence of the parasitic loop of the roll-pitch seeker on the stability of the guidance system and the guidance parameters is analyzed.The simulation results show that the positive and negative feedback characteristics of the disturbance rejection rate parasitic loop have a great influence on the stability of the guidance system. It is necessary to design appropriate guidance parameters according to the characteristics of the parasitic loop to meet the guidance accuracy requirements.