saltyrover_drive 0.1.0 4-wheel differential drive controller for SaltyRover variant. Converts /cmd_vel (Twist) to per-wheel speeds for STM32 via JSON drive4 command. Includes dead-reckoning odometry node. No balance PID required — stable chassis. sl-controls MIT rclpy geometry_msgs nav_msgs std_msgs tf2_ros ament_python ament_copyright ament_flake8 ament_pep257 python3-pytest ament_python