Leo Rover ROS API

Subscribed topics

• cmd_vel (geometry_msgs/msg/Twist)

  Target velocity of the Rover. Only linear.x $[\frac{m}{s}]$ and angular.z $[\frac{rad}{s}]$ are used.

• firmware/wheel_{FL,RL,FR,RR}/cmd_pwm_duty (std_msgs/msg/Float32)

  Target PWM duty cycle for each wheel motor. $[\%]$

  warning

  Cannot be used at the same time as other cmd topics.

• firmware/wheel_{FL,RL,FR,RR}/cmd_velocity (std_msgs/msg/Float32)

  Target velocity of the individual wheels. $[\frac{rad}{s}]$

  warning

  Cannot be used at the same time as other cmd topics.

Published Topics

• merged_odom (nav_msgs/msg/Odometry)

  Merged odometry calculated from wheel encoders and the onboard IMU.

  info

  This is the preferred topic to use for odometry data. Use this topic instead of wheel_odom or firmware/odom.

• wheel_odom (nav_msgs/msg/Odometry)

  Odometry calculated from wheel encoders.

• imu/data (sensor_msgs/msg/Imu)

  Filtered readings from the onboard IMU. The filter does 2 things:

  • Adds a dynamic bias to the gyroscope readings.
  • Adds estimated orientation by fusing the accelerometer and gyroscope data.
  info

  This is the preferred topic to use for IMU data. Use this topic instead of imu/data_raw or firmware/imu

• imu/data_raw (sensor_msgs/msg/Imu)

  Raw gyroscope and accelerometer readings from the onboard IMU.

• imu/rpy (geometry_msgs/msg/Vector3Stamped)

  Roll, pitch and yaw angles calculated from the IMU data. $[rad]$

• camera/image_raw (sensor_msgs/msg/Image)

  Raw, unprocessed image data from the camera.

• camera/camera_info (sensor_msgs/msg/CameraInfo)

  Intrinsic and extrinsic parameters of the camera, such as calibration data.

• camera/image_color (sensor_msgs/msg/Image)

  Color image data from the camera. No different from camera/image_raw.

• camera/image_color/compressed (sensor_msgs/msg/CompressedImage)

  Compressed color image data from the camera.

• camera/image_mono (sensor_msgs/msg/Image)

  Monochrome (grayscale) image data from the camera.

• camera/image_mono/compressed (sensor_msgs/msg/CompressedImage)

  Compressed monochrome (grayscale) image data from the camera.

• camera/image_rect (sensor_msgs/msg/Image)

  Rectified (undistorted) monochrome image data from the camera.

• camera/image_rect/compressed (sensor_msgs/msg/CompressedImage)

  Compressed rectified monochrome image data from the camera.

• camera/image_rect_color (sensor_msgs/msg/Image)

  Rectified (undistorted) color image data from the camera.

• camera/image_rect_color/compressed (sensor_msgs/msg/CompressedImage)

  Compressed rectified color image data from the camera.

• firmware/battery (std_msgs/msg/Float32)

  Current battery voltage reading. $[V]$

• firmware/battery_averaged (std_msgs/msg/Float32)

  Battery voltage estimated from averaging readings from last 30 seconds. $[V]$

• joint_states (sensor_msgs/msg/JointState)

  Current state of the robot joints.

• robot_description (std_msgs/msg/String)

  The URDF description of the robot.

• /parameter_events (rcl_interfaces/msg/ParameterEvent)

  Parameter events (additions, changes or deletions) from all the running ROS nodes.

• /rosout (rcl_interfaces/msg/Log)

  Logs from all the running ROS nodes.

• /tf, /tf_static (tf2_msgs/msg/TFMessage)

  Relationships between TF frames in the ROS network.
  These topics are used by the tf2 library.

Services

• reset_odometry (std_srvs/srv/Trigger)

  Reset odometry position.

• camera/set_camera_info (sensor_msgs/srv/SetCameraInfo)

  Set onboard camera calibration parameters.

• firmware/get_board_type (std_srvs/srv/Trigger)

  Get the type of the controller board.

• firmware/get_firmware_version (std_srvs/srv/Trigger)

  Get the version of the firmware running on the controller board.

• firmware/reset_board (std_srvs/srv/Trigger)

  Perform software reset of the controller board.

• imu_filter/reset_calibration (std_srvs/srv/Trigger)

  Reset the IMU calibration. This will reset the dynamic gyroscope bias.

• system/reboot (std_srvs/srv/Trigger)

  Perform reboot of the onboard computer's system.

• system/shutdown (std_srvs/srv/Trigger)

  Perform shutdown of the onboard computer's system.

Parameters

/camera

• role (type: string, read-only)

  Which StreamRole to use. (possible choices: raw, still, video, viewfinder)

• format (type: string, read-only)

  The pixel format of the camera stream. For possible values, check picamera2 documentation (Appendix A).

• width, height (type: int, read-only)

  The width and height of the camera stream in pixels.

• sensor_mode (type: sting, read-only)

  The desired raw sensor format resolution (format: width:height)

• orientation (type: int, read-only)

  The orientation of the camera in degrees. Possible values: 0, 90, 180, 270.

• frame_id (type: string, read-only)

  The TF frame associated with the camera stream.

info

Apart from the aforementioned parameters, the camera node also translates the libcamera controls into ROS parameters. The camera controls are documented in picamera2 documentation (Appendix C).

/camera/debayer

• .image_color.compressed.jpeg_quality (type: int)

  The quality of the JPEG compression for the color image. Range: 0-100.

• .image_mono.compressed.jpeg_quality (type: int)

  The quality of the JPEG compression for the monochrome image. Range: 0-100.

/camera/rectify_mono

• .image_rect_color.compressed.jpeg_quality (type: int)

  The quality of the JPEG compression for the rectified color image. Range: 0-100.

/camera/rectify_color

• .image_rect.compressed.jpeg_quality (type: int)

  The quality of the JPEG compression for the rectified monochrome image. Range: 0-100.

/firmware

info

The parameters for /firmware node can be overridden by modifying the /etc/ros/firmware_overrides.yaml file.

• wheels/encoder_resolution (type: float)

  The resolution of the wheel encoder in counts per rotation.

• wheels/torque_constant (type: float)

  The torque in Nm produced by the wheel per 1 Ampere of windind current.

• wheels/pid/p (type: float)

  The P constant of the PID regulator.

• wheels/pid/i (type: float)

  The I constant of the PID regulator.

• wheels/pid/d (type: float)

  The D constant of the PID regulator.

• wheels/pwm_duty_limit

  The limit of the PWM duty applied to the motor in percent.

• controller/wheel_radius (type: float)

  The radius of the wheel in meters.

• controller/wheel_separation (type: float)

  The distance (in meters) between the centers of the left and right wheels.

• controller/wheel_base (type: float)

  The distance (in meters) between the centers of the rear and front wheels.

• controller/angular_velocity_multiplier (type: float)

  The angular velocity in cmd_vel command is multiplied by this parameter and the calculated odometry has its angular velocity divided by this parameter.

• controller/input_timeout (type: int)

  The timeout (in milliseconds) for the cmd_vel commands. The controller will be disabled if it does not receive a command within the specified time. If set to 0, the timeout is disabled.

• battery_min_voltage

  The voltage (in Volts) below which the battery is considered low. If the battery goes below this voltage, the LED indicator will start blinking fast.

/firmware_message_converter

• robot_frame_id (type: string, read-only)

  The TF frame associated with the robot.

• odom_frame_id (type: string, read-only)

  The TF frame associated with the odometry readings.

• imu_frame_id (type: string, read-only)

  The TF frame associated with the IMU readings.

• tf_frame_prefix (type: string, read-only)

  The prefix added to the published TF frames.

• wheel_joint_names (type: string[], read-only)

  The names of the wheel joints used in the joint_states topic. The order of the names is: front left, rear left, front right, rear right.

• wheel_odom_twist_covariance_diagonal (type: float[], read-only)

  The diagonal of the covariance matrix for the standard wheel odometry twist readings. The size of the array must be 6, representing the variances for the linear x, linear y, linear z, angular x, angular y and angular z axes.

• wheel_odom_mecanum_twist_covariance_diagonal (type: float[], read-only)

  The diagonal of the covariance matrix for the mecanum wheel odometry twist readings. The size of the array must be 6, representing the variances for the linear x, linear y, linear z, angular x, angular y and angular z axes.

• imu_angular_velocity_covariance_diagonal (type: float[], read-only)

  The diagonal of the covariance matrix for the IMU angular velocity readings. The size of the array must be 3, representing the variances for the x, y and z axes.

• imu_linear_acceleration_covariance_diagonal (type: float[], read-only)

  The diagonal of the covariance matrix for the IMU linear acceleration readings. The size of the array must be 3, representing the variances for the x, y and z axes.

/imu_filter

• gain_acc (type: float)

  Gain for the complementary filter for orientation estimation. The value must be in the range (0, 1).

• do_adaptive_gain (type: bool)

  Whether to use adaptive gain for the complementary filter. If set to true, the gain will be adjusted based on the accelerometer readings.

• bias_alpha (type: float)

  The gyroscope bias estimation gain. The value must be in the range (0, 1).

• do_bias_estimation (type: bool)

  Whether to do bias estimation of the angular velocity (gyroscope readings). If set to false, the gyroscope readings will not be filtered and will be published as is.

• do_save_bias (type: bool)

  Whether to periodically store the gyroscope bias on the disk and load it upon startup.

• bias_save_period (type: int)

  Time interval between current imu bias save (in seconds).

• orientation_variance (type: float)

  The variance of the orientation estimation. Will be used to fill the diagonal of the covariance matrix of the IMU orientation readings. The value must be greater than 0.

/odom_filter

• publish_tf (type: bool)

  Whether to publish the TF frame for the odometry.