By reading this article, we can RenhotecIC understand the difference between geomagnetic sensor, geomagnetic sensor and gyroscope, and the application products of geomagnetic sensor.

　　I. What is a geomagnetic sensor?

　　Geomagnetic field is an inherent resource of the earth, which provides a natural coordinate system for aviation, aerospace and navigation, and can be applied to the positioning orientation and attitude control of spacecraft or ships. The magnetic navigation technology, which uses the space distribution of the earth's magnetic field, is simple, efficient, reliable and anti-interference. It is one of the indispensable basic navigation and positioning methods in developed countries. For example, Boeing aircraft with high degree of automation are loaded with magnetic navigation and positioning systems.


　　II. What is a gyroscope

　　In order to introduce the difference between geomagnetic sensor and gyroscope, the gyroscope is briefly introduced here.

　　The principle of a gyroscope is that the direction of the axis of rotation of a rotating object will not change without external force. People use it to keep direction according to this truth. Then the direction indicated by the axis is read by various methods, and the data signal is automatically transmitted to the control system. We actually use this principle by cycling. The faster the wheel turns, the less easy it is to fall, because the axle has a force to keep level. An instrument that accurately determines the orientation of a moving object, an inertial navigation instrument widely used in modern aviation, navigation, aerospace and national defense industries. The traditional inertial gyroscope has mechanical gyroscope in the main part, but the mechanical gyroscope has high requirements for the process structure.

　　The basic components of the gyroscope are:

　　Gyro rotor (often used synchronous motor, hysteresis motor, three-phase AC motor and other drag methods to make the gyro rotor rotate around the axis of rotation at high speed, and see its speed approximate to constant value);(2) inner and outer frame (or inner and outer ring, which is the structure to obtain the required degrees of freedom of angular rotation of the gyroscope);(3) accessories (refers to torque motor, signal sensor, etc).


　　III. Distinction between geomagnetic sensors and gyroscopes

　　Geomagnetic sensors and gyroscopes can be used in navigation, each with advantages.

　　Gyroscope is an instrument which can measure attitude (using fixed axis) and north finding (using precession) by using the fixed axis and precession of gyroscope, and has high precision in short time and accumulated error in long working time. The geomagnetic field sensor can measure the earth's magnetic field. Without magnetic interference, if we know the local latitude and longitude and altitude, we can use various geomagnetic field models to calculate the magnetic inclination angle, magnetic deviation angle, and then calculate the polar north and attitude, etc. Magnetic field sensors are easily disturbed, but simple and not easy to break.

　　IV. Application of geomagnetic sensors

　　Through the above introduction, we must have a certain understanding of geomagnetic sensors, so, what are the applications of geomagnetic sensors?

　　(i) Application of geomagnetic sensors

　　Before the application of magnetic sensors in mobile phones, mainly used in compass and some games, the most used GPS inertial navigation. So in the eyes of customers and some mobile phone manufacturers, geomagnetic sensors are an optional "luxury ", has always been a high-end mobile phone.

　　However, a new application will greatly promote geomagnetic sensors as a necessary product for mobile phones. This is indoor navigation. Google, Gaude and other traditional map manufacturers have established databases to promote indoor navigation, a LBS-based location service.


　　(ii) A specific geomagnetic sensor system —— geomagnetic vehicle detector TVD-200; and

　　TVD-200 is a buried wireless geomagnetic vehicle detection system, which is used to replace the traditional coil vehicle detector. When the vehicle passes through the embedded area of the detector, the vehicle passes through and passes by detecting the change of the magnetic field around the equipment relative to the earth magnetic field. The wireless geomagnetic vehicle detector can be installed without wiring, without external power supply, simple construction and strong adaptability, which can meet the requirements of collecting and processing parking space information under various complex meteorological conditions.