Research on Low Temperature Drift Suppression of Micro-Machined Gyroscope Based on Self-Calibration Technology

Abstract

Micro-machined gyroscope is an important inertial sensor, which has the advantages of high integration, small size and low power consumption. However, due to the temperature sensitivity of silicon and electronic devices, the bias and scale factor of micro-machined gyroscopes have temperature drift, which limits their engineering application the relatively large process error of micro-machining makes the frequency mismatch between driving mode and detection mode of micro-machined gyroscope, which not only deteriorates the mechanical sensitivity of the gyroscope, but also causes the frequency mismatch between driving mode and detection mode, it also leads to the quadrature error of driving coupling in gyro detection mode. Based on this, firstly, the relationship between the bias factor and the scale factor of MEMS gyroscope and its dynamic and electrical parameters is analyzed. Secondly, a self-calibration capacitance detection scheme based on triangular-electrode based (TEB) is proposed, and the temperature effect of the scheme is analyzed. Finally, the simulation results show that the temperature coefficient of the scale factor decreases from −8845 ppm/°C to 1660 ppm/°C when the temperature range is from −10 °C to 60 °C, the bias temperature coefficient decreased from −0.97°/s/°C to −0.42°/s/°C. The experimental results show that the scheme effectively reduces the temperature sensitivity of the bias and scale factor of the gyroscope.