The mode of primary oscillations of a micromechanical gyroscope (MMG) sensor is provided by an electrostatic comb-drive actuator in which the interaction between the micromechanical structures and electronics occurs by means of a single or differential capacitive sensor. Two pairs of capacitive sensors are traditionally used for frequency stabilization of MMG primary oscillations. The first pair of capacitive sensors excites primary oscillations, while the second measures the amplitude of primary oscillations. The stabilization system provides a continuous frequency tuning of primary oscillations that increases the duration of transition processes, the time of operational readiness, and the instability of the output signal from the secondary oscillation channel of the MMGs. This paper presents a new approach to the primary oscillation control system of the two-component MMG. The method of calculating the natural resonant frequency is based on measurements of the total current passing through the comb-driver actuator capacitances, and a lock-in detection is suggested. This paper consists of the results of the numerical analysis, the description of the proposed approach to the frequency control of the primary MMG oscillations, and the Simulink model of the behaviour of the MMG stabilization system, depending on its mechanical-and-physical properties with regard to a 2% shift of the natural resonant frequency. The frequency control of the primary oscillations at 2% frequency detuning is performed within 0.11 s.
ASJC Scopus subject areas
- Applied Mathematics