Skip to content

Velodyne VLP-16

GitHub code build GitHub last commit

DockerHub image Docker image arch Docker image version Docker image size

🐳 Start Container

Make sure your system meets the system requirements and have followed the setup instructions before using this workspace.

Run the following commands in a Ubuntu desktop environment. If you are using a remote server, make sure you're using a terminal within a remote desktop session (e.g., VNC) instead of SSH (i.e., don't use ssh -X or ssh -Y).

cd ~/ros2-essentials/vlp_ws/docker
docker compose build
xhost +local:docker
docker compose up -d
# The initial build will take a while, please wait patiently.

If your user's UID is 1000, you may replace the docker compose build command with docker compose pull.

The commands in the following sections assume that you are inside the Docker container:

# in a new terminal
docker exec -it ros2-vlp-ws bash

If the initial build somehow failed, run:

rm -r build install
colcon build --symlink-install

Once you have finished testing, you can stop and remove the container with:

docker compose down

Simulation Setup

Add description in defined robot

  1. Declared necessary argument and your own robot_gazebo.urdf.xacro

    <xacro:arg name="gpu" default="false"/>
<xacro:arg name="organize_cloud" default="false"/>
<xacro:property name="gpu" value="$(arg gpu)" />
<xacro:property name="organize_cloud" value="$(arg organize_cloud)" />

  2. Include the velodyne_description package

    <xacro:include filename="$(find velodyne_description)/urdf/VLP16.urdf.xacro" />

  3. Add LiDAR in the robot

    <xacro:VLP-16 parent="base_footprint" name="velodyne" topic="/velodyne_points" organize_cloud="${organize_cloud}" hz="10" samples="440" gpu="${gpu}">
    <origin xyz="0 0 0.1" rpy="0 0 0" />
</xacro:VLP-16>
  • You could refer to more information from veloyne_simulator/velodyne_description/urdf/template.urdf.xacro

Launch LiDAR driver with simulated LiDAR

  • Launch example robot with LiDAR
    ros2 launch velodyne_description example.launch.py
  • Launch the LiDAR data process without driver in another terminal
    ros2 launch vlp_cartographer vlp_driver.launch.py is_sim:=True

Sample Robot

  • A given turtlebot waffle model with VLP-16 is provided in velodyne_simulator/velodyne_simulator/urdf/sample_robot.urdf.xacro
  • Launch the sample robot
    ros2 launch velodyne_description example.launch.py robot:=1

LiDAR setup

Hardware Setup

  • Connect the LiDAR to power.
  • Connect the LiDAR to the computer or router using the provided ethernet cable.

Directly Using Computer

  • Connect the LiDAR to the computer using the ethernet cable.
  • Open the computer settings and navigate to Network > Wired.
  • Set the IPv4 configuration to 'manual' and configure the settings as shown in the image below:

Launch the Driver

Pipeline

  • Data process as following: raw data -> pointcloud -> laser scan -> slam method
  • Velodyne driver: velodyne_driver get the raw data from LiDAR.
  • Transform the raw data to pointcloud: velodyne_pointcloud
  • Transform the pointcloud to laser scan: velodyne_laserscan

Operating in a single launch file

ros2 launch vlp_cartographer vlp_driver.launch.py
  • By the above command, the driver, pointcloud and laserscan will be launched.

Published topics

Topic Type Description
/velodyne_packets velodyne_msgs/VelodyneScan raw data
/velodyne_points sensor_msgs/PointCloud2 Point cloud message
/scan sensor_msgs/LaserScan laser scan message

Test with cartographer

  • In another terminal, launch the cartographer node:
    ros2 launch vlp_cartographer cartographer_demo.launch.py

Bringup

  • Build the docker image and workspace
    docker compose up --build
  • LiDAR driver
    docker exec -it ros2-vlp-ws /home/ros2-essentials/vlp_ws/scripts/lidar-driver-bringup.sh
  • After launching the driver, launch the cartographer in another terminal
    docker exec -it ros2-vlp-ws /home/ros2-essentials/vlp_ws/scripts/lidar-slam-bringup.sh

Reference