Gyroscopes

A gyroscope is a device that uses Earth’s gravity to help determine orientation. Gyro sensors are devices that sense angular velocity which is the change in rotational angle per unit of time. Angular velocity is generally expressed in deg/s (degrees per second). There are three basic types of gyroscope Rotary (classical) gyroscopes, Vibrating Structure Gyroscope and Optical Gyroscopes.

Its design consists of a freely rotating disk called a rotor, mounted onto a spinning axis in the centre of a larger and more stable wheel. As the axis turns, the rotor remains stationary to indicate the central gravitational pull, and thus which way is down. The gyroscope maintains its level of effectiveness by being able to measure the rate of rotation around a particular axis. When gauging the rate of rotation around the roll axis of an aircraft, it identifies an actual value until the object stabilizes out. Using the key principles of angular momentum, the gyroscope helps indicate orientation.

Gyroscopes are available that can measure rotational velocity in 1, 2, or 3 directions. 3-axis gyroscopes are often implemented with a 3-axis accelerometer to provide a full 6 degree-of-freedom (DoF) motion tracking system. A gyroscope would be used in an aircraft to help in indicating the rate of rotation around the aircraft roll axis. As an aircraft rolls, the gyroscope will measure non-zero values until the platform levels out, whereupon it would read a zero value to indicate the direction of down.