MEMS gyroscopes are silicon microelectromechanical gyroscopes. Most MEMS gyroscopes rely on alternating Coriolis forces caused by mutually orthogonal vibrations and rotations. MEMS (Micro-Electro-Mechanical Systems) refers to a complete micro-electromechanical system that integrates mechanical elements, micro-sensors, micro-actuators, signal processing and control circuits, interface circuits, communications and power supplies.
Features of MEMS gyroscopes:
The MEMS gyroscope uses the coriolis theorem to convert the angular velocity of the rotating object into a DC voltage signal proportional to the angular velocity. Its core components are mass-produced through doping technology, lithography technology, corrosion technology, LIGA technology, packaging technology, etc. The main features are
1. Small in size and light in weight, its side length is less than 1mm, and the weight of the core of the device is only 1.2mg.
2. Low cost
3. Good reliability, the working life is more than 100,000 hours, and it can withstand 1000g impact.
4. Large measuring range
Is MEMS Replacing Fiber Optic Gyroscope Technology?
Fiber optic gyroscope is a huge improvement following the laser gyroscope. It belongs to the two-light gyroscope. It uses the Sagnac effect to calculate the angular velocity with the optical path difference. , high reliability, and has been widely used. However, compared with MEMS, it is still very expensive, and nearly a kilometer of optical fiber is wound into a lump, and there are problems with temperature coefficient, reliability, shock resistance, and long storage. Moreover, the current accuracy of MEMS is already 10 and open-loop optical fiber, and has been Going forward to 1, so in some low-end and short-term applications, it will test the thick nerves of optical fiber practitioners, and the advantages of MEMS such as small volume and weight, low cost, chip batch size, and high reliability are very obvious, but the accuracy of MEMS will enter the market within 10 years. 0.1 is a bit difficult, so in the world where 0.1 to one thousandth can be optical fiber, it cannot be replaced in a short time.
How Fiber Optic Gyroscopes Work
The implementation of fiber optic gyroscopes is mainly based on Segnick's theory: when a light beam travels in a ring-shaped channel, if the ring-shaped channel itself has a rotational speed, then the time required for the light to travel in the direction of the channel's rotation is longer than that in this direction. It takes more time for the channel to turn in the opposite direction to advance. That is to say, when the optical loop rotates, in different advancing directions, the optical path of the optical loop will change relative to the optical path of the loop when it is stationary. Using the change of the optical path, the phase difference of the two optical paths or the change of the interference fringe can be detected, and the angular velocity of the optical path can be measured, which is the working principle of the fiber optic gyroscope.
