Overview

The WRC parameter group configures the Closed-Loop Wheel Speed controller for ArduRover.

Without WRC, a rover uses "Open-Loop" control, sending a fixed throttle percentage. With WRC, the autopilot uses feedback from Wheel Encoders to ensure the wheels are spinning at exactly the commanded speed, regardless of surface friction, slope, or battery voltage.

Key Concepts

1. Velocity Feedback

The system calculates the error between the "Commanded Wheel Speed" and the "Actual Wheel Speed" (measured by encoders).

• WRC_ENABLE: Master switch.

2. PID Tuning

(If present in group) Standard gains to control the responsiveness of the wheel motor response.

Integration Guide

1. Hardware: Install and calibrate wheel encoders (WENC group).
2. Enable: Set WRC_ENABLE = 1.
3. Tuning: Adjust gains to ensure the rover can maintain a crawl up a hill without stalling or jerking.

Developer Notes

• Library: libraries/AP_WheelEncoder/AP_WheelRateControl.cpp.
• Dependency: This group is functionally useless without the WENC group being configured first.