Wheel Encoders

Rover supports up to two “AB” wheel encoders like those in this Pololu motor which can be used to improve position estimation especially when no GPS is used.

Connection and Setup

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To enable position estimation using the wheel encoders the EKF3 must be used and configured as follows:

After making the above changes the autopilot should be rebooted

Ground Testing

The WHEEL_DISTANCE MAVLink message shows the total distance travelled by each wheel in real time. Mission Planner’s MAVLink Inspector can be used which can be opened by pressing Ctrl-F and then pushing the “MAVLink Inspector” button.

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DataFlash logging

The wheel encoder data including total distance travelled by each wheel appears in the WENC dataflash log messages.