Designand Development Of Vibration Condition Monitoring System For Gyro Motor Used By Satellite

Gyroscope as a basic inertial sensor has been widely used in the attitude controland orbit control system of various domestic and international satellite, which is thecore components of the satellite navigation and guidance control system.The positioningaccuracy and reliability of gyroscope directly affect the success or failure of thesatellite’s assignment. The gyro motor support gyroscope with moment of momentum,whose production quality and operational performance directly determines thereliability and service life of the gyroscope. Therefore, vibration condition monitoringfor gyro motor is of importance. The superiorities and advantages are to judge whetherthe gyro motor had malfunction, improve the screening efficiency of the gyro motor andensure that the gyro motor installed in the gyroscope in a safe and reliable state.Reducing unnecessary economic losses is the final benefit.Starting at the purpose of vibration signal obtained from the gyro motor, this paperfirstly design the vibration signal test bench of gyro motor. Based on modal analysistheory, the finite element analysis software are used to complete the bench modalanalysis. The results show that the test bench whose first natural frequency is not equalto power drive frequency of gyro motor is safe and reliable. Driving power of gyromotor is constitute of double channel signal generator and power amplifier. Somereasonable sensor, data acquisition card and IPC composed a data acquisition system totest vibration signal of gyro motor, which provides original data source for vibrationanalysis and state monitoring of gyro motor.After obtaining the vibration signal, based on wavelet packet analysis theory, thevibration signal is decomposed by using the orthogonal wavelet packet “db3” at threelayer and eight decomposed sub-bands are reconstructed based on Mallat algorithm.According to the characteristics of typical vibration failure of rotor and bearing of gyrorotor, this paper extract the corresponding state feature information of the gyro motorand then compare its power spectrum with pre-established reference standard in order tocomplete the vibration condition monitoring of gyro motor. With numerical exampleand experimental sample data, the wavelet packet analysis could effectively extractvibration the state feature information of the gyro rotor and bearing, which achievevibration condition monitoring for gyro motor.This paper makes use of the C++programming language to achieve the dataacquisition functional module for vibration signal, the time domain and frequencydomain analysis functional module for vibration signal, the calculation functionalmodule for vibration fault characteristic frequency of gyro motor,the vibration conditionmonitoring functional module for gyro motor using the "top-down" modular designapproach based on "message in response to the programming mode”. In order to queryand callback the historical condition data by user, this article design the data management database of a gyro motor condition by taking advantage of Access2003database so as to store and output vibration test data.After finishing the calibration of various sensors and data acquisition system, thevarious functional modules of the software system are tested and verified throughexperimental data to ensure the system in a safe and reliable operation. The analysisresults show that the system can be safely and reliably operated and accurately completethe vibration analysis and condition monitoring of gyro motor.