The Study Of Stiffness Measurement Of Dynamic Air Bearing Based On Wireless Data Transmission

Gyro motor of dynamic pressure air bearing is the heart of gyro instruments, and was widely used in inertial equipment and device. The gas film stiffness of air bearing reflected its carrying capacity, was an important index of air bearing quality. The research for the dynamic stiffness of air bearing was very significant for the improvement of accuracy and reliability of gyro equipment. The stiffness of dynamic pressure air bearing was calculated by the film thickness in the condition of bearing running. Because the film thickness was micrometer, the resolution of the measurement equipment must be nanometer. Non-contact capacitance micrometer technology was one of important choice for measurement of film thickness, because of its fast dynamic response, temperature stability, high precision, and high natural frequency of system.Now the requirement for stiffness measurement of dynamic pressure motor in static state was satisfied using existing capacitance micrometer sensor at home and abroad. But measurement of dynamic stiffness can not be realized using existing product, especially in the condition of 20g random vibration. Therefore, the research for dynamic stiffness measurement equipment of dynamic pressure motor was an emergency.Based on analysis for stiffness measurement methods of air bearing, and combining the existing shortage of capacitance micrometer in dynamic measurement, proposed air bearing stiffness measuring system based on wireless data transmission, the work includes:(1) Hardware selection, hardware design of dada collection and wireless transceiver circuit were achieved based on design scheme. Two PCB boards for wireless sending and receiving data were made. Hardware welding and commissioning were completed.(2) Software design of wireless data collection system was achieved. Data A/D conversion and wireless data communication were realized. corresponding anti-interference deaign and test for bit error rate and packet loss were made based on analysis for types of possible interference sources during communication.(3) PC application software in MFC was complied. Data showing in PC, digital filtering for data from capacitance micrometer and nonlinear error compensation were achieved. Then data waveform was drown for users. (4)At last, general test and analysis for capacitance micrometer dynamic stiffness test system based wireless data transmission were achieved. feasibility of scheme was verfied.