Research On Redundant Design And Switching For Servo Loop Of Inertial Platform

Inertial technology is a discipline applied to the object attitude control and motion trajectory control. The platform inertial system, taking inertial technology as the core part, uses inertial sensor to sensitive and obtain carrier angular motion and linear motion information, and furthermore, provides speed, position and attitude information to guidance system. Due to its full autonomy, anti-interference and the advantages of the good concealment, the platform inertial system still has an irreplaceable role in strategic weapon systems up to now.To meet the needs of the weapon system under the new situation of the combat, the inertial platform system must have the ability to work continuously with trouble-free. As the basis part of inertial platform system, the servo loop system has a great demand to be more robust to improve the reliability of inertial platform system.This paper proposed a redundant circuit design based on DSP, and carried on research on the fault detection, arbitration and switching technologies, making it possible to switch the platform circuit to redundant channel rapidly and smoothly when servo loop works failure, which to ensure platform system work normally.First of all, this paper introduced the structure of servo loop, expounded the platform servo loop composition and the working principle, explained the establishment of a servo loop control system mathematical model, and introduced the main performance index of the circuit design.Second, this paper analyzed the failure mode of the servo loop, took reliability prediction of the original circuit design, proposed three kinds of redundancy design, and after analyzing and comparison on three kinds of schemes, the final design of redundant circuit had been determined.After that, using the domestic components, this paper completed the redundancy scheme design, circuit fault detection scheme, arbitration and switching scheme design, and proposed the key electrical parameters selection and calculation method, the circuit schematic design and PCB design were also available.Finally, the method of simulation of fault injection mode had been taken to test the redundant circuit design and platform system. Basing on the calculation of the main technical indexes and test, the correctness and reliability of the design had been fully verified.