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Version: ROS 2 Jazzy

3D Lidar

Three dimensional LiDARs provide a pointcloud of all points detected by several planar scanners at various angles, which is published as a sensor_msgs/PointCloud2 message. It is important to accurately position the LiDAR in the visual description of the robot to ensure that the scanned points are accurate with respect to the robot.

Supported 3D Lidars​

Ouster OS1​

lidar3d:
    - model: ouster_os1
      urdf_enabled: true
      launch_enabled: true
      parent: default_mount
      xyz: [0.0, 0.0, 0.0]
      rpy: [0.0, 0.0, 0.0]
      ros_parameters:
        ouster_driver:
          sensor_hostname: 192.168.131.20
          udp_dest: 192.168.131.100
          lidar_port: 7502
          imu_port: 7503
          proc_mask: IMU|PCL|SCAN|IMG|RAW|TLM
          use_system_default_qos: false
          cap_type: halo
          base_type: base

Package and Setup​

Ouster lidars use the ouster_ros driver. This is an open-source driver, maintained by the manufacturer.

For more specifics on the way Clearpath's configuration system launches the ouster_ros nodes, see the Ouster launch file and the default parameter file in clearpath_sensors.

Base & Cap​

The Ouster lidar can be configured with different base and cap options:

  • base_type: one of base (default) or none.
  • cap_type: one of halo (default) or fins.

The table below shows all combinations of base and cap options:

cap_type
halofins
base_typebase
none

Seyond Robin W​

lidar3d:
  - model: seyond_lidar
    urdf_enabled: true
    launch_enabled: false
    parent: default_mount
    xyz: [0.2, 0.0, 0.0]
    rpy: [0.0, 0.0, 0.0]

Mesh-Only Support​

The Seyond Robin W is only supported as a mesh in robot.yaml; it is intended to be managed by Clearpath's OutdoorNav software, which uses its own set of drivers and launch files that do not directly integrate with the robot configuration yaml.

Velodyne Lidar​

# Model VLP16
lidar3d:
  - model: velodyne_lidar
    urdf_enabled: true
    launch_enabled: true
    parent: base_link
    xyz: [0.0, 0.0, 0.0]
    rpy: [0.0, 0.0, 0.0]
    ros_parameters:
      velodyne_driver_node:
        frame_id: lidar3d_0_laser
        device_ip: 192.168.131.25
        port: 2368
        model: VLP16
      velodyne_transform_node:
        model: VLP16
        fixed_frame: lidar3d_0_laser
        target_frame: lidar3d_0_laser
# Model 32C
lidar3d:
  - model: velodyne_lidar
    urdf_enabled: true
    launch_enabled: true
    parent: base_link
    xyz: [0.0, 0.0, 0.0]
    rpy: [0.0, 0.0, 0.0]
    ros_parameters:
      velodyne_driver_node:
        frame_id: lidar3d_0_laser
        device_ip: 192.168.131.25
        port: 2368
        model: 32C
      velodyne_transform_node:
        model: 32C
        calibration: "/opt/ros/jazzy/share/\
          velodyne_pointcloud/params/VeloView-VLP-32C.yaml"
        fixed_frame: lidar3d_0_laser
        target_frame: lidar3d_0_laser

Package and Setup​

The Velodyne LiDARs use the velodyne_driver ROS 2 Package. The driver is open source, maintained by the ROS community, and hosted on GitHub. Unlike other drivers, the visual description of the device is hosted in a separate repository. The description package, along with the simulator, is maintained by Dataspeed and hosted on BitBucket.

For more specifics on the way Clearpath's configuration system launches the velodyne_driver, see the Velodyne launch file and the default parameter file in clearpath_sensors.

Model​

There are several types of Velodyne LiDAR. To switch between these, the model parameter must be set under the both the velodyne_driver_node and the velodyne_transform_node, and the calibration parameter must be set under the velodyne_transform_node.

NameModelCalibration
Puck"VLP16""VLP16db.yaml"
Puck Hi-Res"VLP16""VLP16_hires_db.yaml"
Ultra Puck"32C""VeloView-VLP-32C.yaml"
VLS-128"VLS128""VLS128.yaml"
HDL-32E"32E""32db.yaml"
HDL-64E"64E""64e_utexas.yaml"
HDL-64ES2"64E_S2""64e_s2.1-sztaki.yaml"
HDL-64ES3"64E_S3""64e_s3-xiesc.yaml"

When setting the calibration parameter, prepend the path /opt/ros/jazzy/share/velodyne_pointcloud/params/ to the calibration file name in the table above.

Hesai Lidar​

lidar3d:
  - model: hesai_lidar
    urdf_enabled: true
    launch_enabled: true
    parent: lidar3d_row_link
    xyz: [0.0, 0.0, 0.0]
    rpy: [0.0, 0.0, 0.0]
    ros_parameters:
      hesai_driver:
        config_path: /path/to/hesai/config/file0.yaml
  - model: hesai_lidar
    urdf_enabled: true
    launch_enabled: true
    parent: lidar3d_row_link
    xyz: [0.1, 0.1, 0.1]
    rpy: [0.0, 0.0, 0.0]
    ros_parameters:
      hesai_driver:
        config_path: /path/to/hesai/config/file1.yaml

Package and Setup​

The Hesai LiDAR uses the hesai_ros_driver ROS 2 driver. The driver is open source, maintained by Hesai Technology, and hosted on GitHub - HesaiLidar_ROS_2.0. The hesai_ros_driver nodes depend on the HesaiLidar_SDK_2.0. The hesai_ros_driver ROS2 package and SDK are not installed by ROS dependencies and need to be built against the specific version installed on your computer. Therefore, you will have to install these manually by following the instructions in the HesaiLidar_ROS_2.0 repository.

The hesai_ros_driver only accepts one single ROS parameter which is config_path as shown above. The config_path points to a configuraiton file formated as shown in the HesaiLidar_SDK_2.0 config.yaml.

Each Hesai LiDAR must be listed first under lidar3d in the robot.yaml file and provide a different the config_path. Each Hesai LiDAR must point to a unique config.yaml. For the first Hesai LiDAR listed in the robot.yaml the following parameters in the config.yaml must be modifed as shown:

lidar:
  - driver:
    ...
      lidar_udp_type:
        device_ip_address: 192.168.131.25
        ...
        multicast_ip_address: 192.168.131.1
    ...
    ros:
      ros_frame_id: lidar3d_0_laser    
    ...

Any additional Hesai LiDAR should increment the device_ip_address (first lidar ip = 192.168.131.25, second lidar ip = 192.168.131.26, etc.) along with the ros_frame_id (first lidar frame ID = lidar3d_0_laser, second lidar frame ID = lidar3d_1_laser, etc.) The IP of the physical Hesai LiDAR must be updated as well. See the User Guide for the XT32 Hesai Lidar that can be downloaded here: https://www.cratustech.com/downloads/.

The change of multicast_ip_address should be set according to the Reserved IP Addresses. The value of 192.168.131.1 should be used if the hesai lidar is connected to the Primary Computer.

The user can change any other parameter in the config.yaml based on their own use case.

Model​

There are several types of Hesai LiDAR models. Currently only the XT32 is supported.

Mesh-Only Support​

The Hesai XT32 Lidar is only supported as a mesh in robot.yaml.

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