Research On Fault Diagnosis Method Of Space Manipulator Reducing Mechanism

Space manipulator is an indispensable auxiliary equipment for the work and maintenance of the space station.It is a highly integrated electromechanical component.It is a highly integrated electromechanical component.It has a high degree of complexity and multitasking.The normal operation of space manipulator is an effective guarantee for its complex tasks.Therefore,the real-time monitoring and diagnosis of the health condition of the space manipulator is the primary guarantee for the normal operation of the space equipment.Although the research of the space manipulator in China is still in the experimental stage,the technology is not fully mature,but it is urgent to carry out the technology forward research in the related fields.The reducing mechanism of the space manipulator is one of the core modules of the space manipulator,and the reducing mechanism mainly completes the function of the movement transmission and the arm link.The reducing mechanism of space manipulator consists of two parts: servo motor and reducer.This topic mainly aims at the reducing mechanism on the space manipulator,and carries out the research on the health condition monitoring in the ground laboratory,and provides the reference for the follow-up research in the related fields.On the basis of brief introduction of the development of the space station,the structure,composition and function of the space manipulator were analyzed.The types and causes of the possible faults of the manipulator were analyzed.The tooth surface wear and the fault of the teeth in the reducer were selected,and the vibration of the motor and the fault of the rotor bar were taken as the diagnosis object.The general technical scheme of fault diagnosis was formulated.Vibration signal and electrical signal were selected as the carrier of fault information.The acquisition circuit of fault diagnosis signal was designed,and the related software was compiled.The test system was built,and the fault free and analog fault signals were tested.The characteristic parameters of the signal diagnosis were extracted and the feature information base was set up.The diagnosis of the ground simulation fault was realized by the support vector machine.The assembly and debugging of the diagnosis system of the reducing mechanism had been completed.Through the test of multiple samples,the fault identification rate of gear reducer for gear reducer reached 99.6%,the fault recognition rate of gear reducer reached 98.4%,the fault recognition rate of abnormal vibration of servo motor reached 61%,the fault recognition rate of rotor broken bar of servo motor reached 100%.The main contents of this paper are as follows:(1)The types,characteristics and possible causes of the fault of the manipulator are analyzed,and the diagnosis objects and fault types were determined.(2)The overall technical plan of the fault diagnosis has been worked out,the signal acquisition sensor has been selected,the corresponding test circuit has been designed,and the corresponding circuit has been made.(3)The characteristic parameters of the detection signal were extracted,and the statistical analysis of the characteristic parameters of the fault and the fault free signals was carried out respectively,and the fault mode library was obtained.(4)Support vector machine(SVM)theory was applied to fault recognition,and the effective recognition and diagnosis of faults were realized by using the fusion features.(5)The related software was compiled,and the diagnosis system initialization,data collection,storage and processing were compiled,and the algorithm of diagnosis and recognition was compiled.(6)A simulation test system has been built,and the test and diagnostic tests have been carried out.The results show that the fault of the reducing mechanism can be effectively diagnosed.