Before talking about the EPSON gyroscope, let us understand the principle and history of the gyroscope.
The early gyroscope was a mechanical device, the main part of which was a rotor that rotated at a very high angular velocity to the rotating shaft. The rotor was installed in a bracket; an inner ring frame was added to the central axis of the rotor XX1, then the gyroscope could be used. Freely move around the plane on two axes; then, add an outer ring frame outside the inner ring frame; this gyroscope has two balance rings, which can move freely around the plane three axes, which is a complete gyroscope.
In today's common smart phones, game controllers and other devices are micromechanical gyroscopes (MEMS gyroscopes). MEMS gyroscopes use Coriolis force—the tangential force that a rotating object receives when it moves in a radial direction. By adding an oscillating starting voltage to the capacitor plate in the radial direction to make the object move in the radial direction, the capacitance change caused by the lateral Coriolis force movement, because the Coriolis force is proportional to the angular velocity, so the change in the measured capacitance can be calculated Angular velocity.
EPOSN gyroscope uses QMEMS gyroscope, that is, quartz crystal (QUARTZ) + micromechanical (MEMS) gyroscope. The so-called QMEMS refers to those crystal components that use precision processing (lithography) technology on quartz raw materials, integrate various functions related to mechanics, electronics, optics, and chemistry, and have high precision, high stability and other value-added crystal components.
By cutting the quartz crystal as H, the vibrating arms on both sides, and the zero output at the center, this structure can make the vibrating arms on both sides of the gyroscope vibrate in contrast, and then the detection arm can accurately detect whether there is vibration or rotation of the carried object. When the angular velocity sensor is relatively stable and does not rotate, the data of the vibrating arms on both sides relative to the center is used as the reference value. When rotation occurs, due to the piezoelectric effect of the crystal, the vibrating arms on both sides of the center will have different deflection values. According to this deflection , The angle value calculated by the processor is output through the communication interface, and the user will directly get the angle value sent by the communication interface.
The reason why EPOSN chose the production process of quartz crystal (QUARTZ) + similar to semiconductor MEMS is firstly because the structure of the traditional MEMS gyroscope oscillator is very complicated, including AD converter, temperature compensation circuit, bias current circuit, etc., its biggest weak link It is because the temperature characteristics change very sharply, the detection range of the gyroscope is limited to about +/-2g; while the QMEMS gyroscope uses quartz crystal as the component, the hardness and physical and chemical properties of the quartz crystal are stable, and the frequency basically does not change with temperature. The internal oscillation loss is also minimal, and the QMEMS gyroscope can extend the range to about hundreds of g. Therefore, QMEMS gyroscopes are very suitable for electronic devices that pursue high precision and high stability.