Study On The Temperature-dependent Performance And Compensation Methods For Cupped Gyroscope

The cupped gyroscope is a new vibrating inertial sensor，which senses the angularrate based on the inertia effect of the elastic wave in the cupped resonator. The cuppedgyroscopes have high operation accuracy, simple structure, easy of mass production,low cost and so on. At the present, the temperature drift is one of the most seriousproblems, which limits the application of the cupped gyroscope.In this dissertation, the research object is the temperature characteristic of thecupped gyroscope, the frequent-temperature characteristic and the bias-temperaturecharacteristic are researched both in theory and experiment. Based on the plentifultemperature experiments, the mathematical model of the temperature drift is established,which is used to compensate the output of the cupped gyroscope. The research resultsare shown as follows:1. The operating principle and the reason of the temperature errors of the cuppedgyroscope are analyzed. With the changing of the temperature, the elastic modulus,Poisson ratio and the density of the material is changed. Since the existence of themanufacturing tolerance and the material inhomogeneity, the vibration rigidity axis willchange with the variation of the temperature, which causes the variation of the output ofthe cupped gyroscope.2. The influence of the temperature on the drive frequency and the bias isresearched through theory analysis and experiments. The drive frequency and zero biasat different temperature points and their repeatability are tested. The characteristics ofthe drive frequency and the zero bias when the temperature is continuously change areresearched, the results show that the temperature testing error cause the frequencyhysteresis. The relationship between the drive frequency and the zero bias is tested, andthe testing results show that the drive frequency can reflect the zero bias’s changerapidly.3. The compensating methods to eliminate the temperature bias drift are researched.In order to be easily applied, the polynomial model is chosen. The bias-temperature andthe bias-frequency models are established respectively. Without compensation, the biasdrifts6.33°/s when the temperature changes from-40℃to60℃. After thecompensation, the bias-temperature model can decrease the bias drift to1.15°/s, and thebias-frequency model can decrease the bias drift to0.45°/s remarkably.4. The compensate system based on the temperature sensor and the compensatesystem based on the bias-frequency model are built. The hardware circuit and thecompensating program are designed. The equivalent accuracy measuring principle isused to measure the drive frequency, and a MCU is used to realize this method. Themeasuring accuracy of this method can research to10-3Hz, which is enough for the compensating system.