Thermal Analysis Of The Liquid Floating Rotor Type Micromachined Gyroscope

MEMS micro-gyroscope as a collection of MEMS technology and gyrotechnology is a hot topic of research in the field of inertial sensors. The thermalcharacteristics of the gyro is the key to stability and sensitivity of the device.This paper studied thermal characteristics of a new type of MEMS liquid floatingrotor gyro with the method of combining simulation and experimental researchand analysis.This paper first described the structure and working principle of the liquidfloating rotor gyro, then established mathematical and finite element model ofthe heat source rotor system and stator system. Secondly, used the COMSOLMultiphysics software modeling and simulating the temperature distribution ofthe gyroscope and contrasted three different viscosity coefficient floating fluid ofgyro in the low, medium, high speed when the temperature rise situation andanalyzed of heat transfer paths and temperature gradient. Thirdly, used theinfrared camera to test the steady state temperature distribution of gyro. The testresult verifying the simulation is reasonable indicated that in steady speed whenthe temperature rise, the simulation of the temperature error is less than1℃compared with the test result. Drawed out the maximum temperature of the statorand rotor regions with the low temperature curve and analyzed the gyro threefloating liquid temperature gradient is0.3℃to0.5℃. Finally, used COMSOLsimulating the Marangoni convection caused by the temperature gradient offloating liquid, and analyze the influence of thermal convection on the velocityfield of floating liquid. The temperature change of floating liquid is no longerlinear when the temperature difference is0.05K; temperature field and velocityfield coupled when the temperature difference is2K. Analyzed and calculatedthe existence of temperature gradient of floating liquid disturbed torque on therotor gyro error model of the first coefficient D1.