This paper introduces an electrothermally actuated resonant microgyroscope and shows that how a thermal actuator can have a proper performance in the drive mode. In the proposed microgyroscope a v-shaped electro thermal actuator is utilized to drive the proof mass in the drive mode whereas parallel plate electrodes are used for sensing the rotation induced Coriolis force in the sense mode. An intermediate mass and decoupling beams decouples the drive and sense mode that leads to decreasing mechanical crosstalk. Higher sensitivity is achieved by designing the drive and sense mode resonant frequencies being close to each other. The analytical analysis was done based on the motion equations after which the resonant frequency of drive and sense mode were calculated. The modal analysis, which was performed using COMSOL, predicted the drive and sense resonant frequency at 2001Hz and 1998Hz respectively. The results of both methods were in satisfactory agreement. In addition, the function of the gyroscope was simulated while applying a sinusoidal voltage. The frequency response of the drive mode was measured both using analytical equations and numerical simulations which showed a good agreement. The amplitude of the displacement in the drive mode at resonant frequency presented that an electrothermal actuator can be suitably excite proof mass. The advantages of an electrothermal actuator over an electrostatic actuator in the drive mode are; low damping factor; low excitation voltage and electrical circuits of lower complexity.
Index Terms-Microgyroscope, electrothermal actuator, resonant frequency, frequency response.Mohsen Hamedi is a professor of manufacturing in School of Mechanical Engineering, University of Tehran, Iran where he teaches graduate and undergraduate courses. He obtained his PhD in 1995 from UNB, Canada and M.Sc. and B.Sc. from University of Tehran respectively. Dr. Hamedi has supervised more than 60 PhD and M.Sc. dissertations. He has published more than 120 papers in the refereed international journals and conferences. His research area of interests are micro-sensor and micro-actuator design and fabrication, mechanica energy harvesting and manufacturing process optimization.