Design of Micro Inertial Measurement Unit Based on Micromachined Thermal Expansion Gas Gyroscope

Micro machined Thermal Expansion Gas Gyroscope (MTEGG) based on the principle of thermal expansion is a novel MEMS gyroscope. It is more convenient to use MTEGG to design MIMU, because MTEGG is not only as an angular rate sensor but also as an accelerometer. In this paper, a novel MIMU based on the MTEGG is discussed. The scheme of MTEGG is introduced first, basing on it, the design of detecting & controlling circuits is proposed. Then, the design of MIMU which includes structure design, selection of MCU, data acquisition design, and MCU software design is introduced. In addition, experimental methods of zero-bias stability and scale factor are also introduced. In the end, the designed MIMU based on MTEGG has been tested by experiments. The measurement result of the MIMU show that the zero-bias stability for the angular rate and acceleration of the designed MIMU in x y z axis is 0.9723 mV/(°·s-1), 0.96401 mV/(°·s-1), 0.90556 mV/(°·s-1), 2.568 mg, 2.603 mg, 2.512 mg respectively, while the scale factor of them is 0.541°/s, 0.564°/s, 0.583°/s, 0.72375 mV/g, 0.72301 mV/g, 0.72446 mV/g separately, and the designed MIMU can be used in common navigation field.