Temperature drift suppression for micro-electro-mechanical system gyroscope based on vibrational-displacement control with harmonic amplitude ratio

Micro-electro-mechanical system gyroscope detection output is susceptible to drift due to ambient temperature variations. Furthermore, the drive-mode vibration amplitude is affected by the signal pickup circuit and structural parameters, which significantly influence the temperature drift of the bias and scale factor (SF). This study proposes a vibration amplitude control method based on harmonic amplitude sideband-ratio (SBR), namely SBR-AGC, which characterizes the vibration amplitude using the harmonic amplitude ratio of the vibrational electrical signal. The constancy of vibration amplitude is maintained via closed-loop control to suppress bias and SF temperature drift. The experimental results on cobweb-like disk resonator gyroscope reveal that the temperature coefficient of bias in the SBR-AGC mode lies within −20 to 60°C and decreases by 36%, and the temperature coefficient of the SF lies within −10 to 50°C and decreases by 49.7%. Therefore, the environmental adaptability of the gyroscope is effectively improved.