Gyroscope is a kind of sensor used to measure angular velocity, and its principle is to use gyro effect. Gyro effect means that when an object rotates, the air around the object will produce relative motion, which will produce a force on the object, called gyro force. Gyroscope usually consists of a freely floating rotor and a sensitive electrode. When the rotor rotates, it will produce electromotive force, which depends on the angular velocity of the rotor. Gyroscope can measure angular velocity by measuring this electromotive force.
An accelerometer is a sensor for measuring acceleration. Its principle is to use Newton's second law, that is, F=ma, where f is force, m is mass and a is acceleration. An accelerometer usually consists of a freely suspended mass and a sensitive electrode. When an object accelerates, the mass will produce electromotive force, which depends on the acceleration. An accelerometer can measure acceleration by measuring this electromotive force.
The output of three-axis angular velocity sensor is the vector value of angular velocity and acceleration of three axes. These data can be used to describe the rotation and motion state of objects. For example, a three-axis angular velocity sensor can be used to measure the attitude of an airplane, the movement of a robot or the trajectory of a car.
The accuracy of three-axis angular velocity sensor depends on the accuracy of gyroscope and accelerometer, which can usually reach one thousandth accuracy. Three-axis angular velocity sensor is usually small in size and can be easily installed on various devices.
Common three-axis angular velocity sensors are MPU6050, L3G4200D, BMI 160, etc. These sensors have high cost performance and are widely used in various fields.