Introduction to Odometry

Odometry is the process of tracking a robot’s position and orientation on the field using sensors, typically wheel encoders. In FTC, odometry is essential for enabling your robot to navigate autonomously and perform tasks with precision.

With odometry, your robot can follow complex paths, score game elements, and return to specific locations during autonomous periods. It is a foundational concept for advanced autonomous routines in FTC.

Odometry systems use encoders attached to wheels to measure how far the robot has traveled. By analyzing the movement of these wheels, the robot can estimate its position (X, Y) and heading (angle) on the field. Most FTC robots use either drive encoders or dedicated 'dead wheels' for this purpose.

For more on the theory, see gm0: Odometry.

There are several ways to set up odometry on an FTC robot:

• Drive Encoder Odometry: Uses the encoders built into the drive motors. Simple, but can be inaccurate due to wheel slippage.
• Dead Wheel Odometry: Uses unpowered wheels with encoders for more accurate tracking.
• Two-Wheel vs. Three-Wheel: Two-wheel setups can track position but not always heading; three-wheel setups can track both position and orientation.

Odometry is not perfect. Errors can come from wheel slippage, misalignment, or sensor noise. Understanding these limitations helps you design more robust autonomous routines and troubleshoot issues during competition.