Parametrically Excited Micromechanical Absolute Angular Velocity Sensor

Abstract

It is shown that the information redundancy of a three-degree hybrid micromechanical gyroscope (the output information of the device is contained not only in the amplitude of the rotor deflection, but also in the frequency and phase of its oscillations) can be used to measure the traditionally inaccessible component of the absolute angular velocity of the base. A method proposed for determining the third component of the angular velocity of a gyroscope from the magnitude of the phase shift of its rotor oscillations. The method is basing on parametric excitation of the device by modulating the angular speed of rotation of the drive. A mathematical model of the gyroscope motion in a rotating coordinate system built. Computer simulation of the excited gyroscope operation carried out. Graphical solutions are presenting, showing the possibility of determining the value of the third component of the angular velocity by the measured phase shift of the rotor oscillations relative to the resonance value. An algorithm for extracting such information proposed. Conclusions made about the possibility of endowing a three-degree hybrid micromechanical gyroscope with the properties of a meter of three mutually orthogonal components of an arbitrarily oriented vector of the absolute angular velocity of the base.