Harware Node

Overview

This package provides a ROS node to control robot movement on real (not simulated) hardware. More specifically, it communicates with ODrive (BLDC motor controller) and Teensy MCU (manages servo motors for steering).

Paramethers

• model_config — path to model.yaml file, used by model::Model class (see here for details)
• steering_config — path to steering.csv file (see here for details)
• odrive_timeout (default: 250 ms) — odrive watchog timeout (milliseconds). Adjust to be slightly higher than the interval between control messages (/control/command topic).
• status_report_rate (default: 1 Hz) — rate of messages in /hardware/status topic.
• telemetry_report_rate (default: 20 Hz) — rate of messages in /hardware/telemetry topic.
• odrive_axis (default: “axis1”) — name of odrive axis with connected motor.
• teensy_serial_port (default: “/dev/ttyTHS0”) — path to serial port to communicate with teensy.
• teensy_serial_speed (default: 500000 baud) — teensy serial connection speed (baud rate).

Topics

Input:

• /control/command — current velocity and steering target (see here).
• /control/mode — current mode of operation (see here).
  • OFF = motion disabled (odrive state = IDLE, motor coils off).
  • REMOTE = robot is controlled via remote (gamepad).
  • AUTO = robot is controlled programmatically.

Output:

• /hardware/status — global status of hardware (see here). In case of odrive failure, message will contain list of internal error codes. Published with a regular rate = telemetry_report_rate, also published immediatly after odrive error occurs.
• /hardware/telemetry — odrive internal metrics, useful for diagnostic (see here). Published with a relatively high rate = telemetry_report_rate.