Gyroscopes - Hardware¶
Note
This section covers gyro hardware. For a software guide to gyros, see Gyroscopes - Software.
Gyroscopes (or “gyros”, for short) are devices that measure rate-of-rotation. These are particularly useful for stabilizing robot driving, or for measuring heading or tilt by integrating (adding-up) the rate measurements to get a measurement of total angular displacement.
Several popular FRC devices (known as “inertial measurement units,” or “IMUs”) combine both an accelerometer and a gyroscope. Some popular examples are:
Types of gyros¶
There are two types of Gyros commonly-used in FRC: single-axis gyros, and three-axis gyros.
Single-axis gyros¶
As per their name, single-axis gyros measure rotation rate around a single axis. This axis is generally specified on the physical device, and mounting the device in the proper orientation so that the desired axis is measured is highly important. Single-axis gyros generally output an analog voltage corresponding to the measured rate of rotation, and so connect to the roboRIO’s analog input ports.
The Analog Devices ADXRS450 FRC Gyro Board that has been in FIRST Choice in recent years is a commonly used single axis gyro.
Three-axis gyros¶
Three-axis gyros measure rotation rate around all three spacial axes (typically labeled x, y, and z).
Peripheral three-axis gyros may simply output three analog voltages (and thus connect to the analog input ports, or (more commonly) they may communicate with one of the roboRIO’s serial buses.