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LDROBOT LD-19

Documents

Setup

Note

The setup of specific udev rules for USB-based 2D laser scanners may not be possible because it is the CP2102N USB to UART Bridge Controller (or other alike) that is communicating with the operating system and not the sensor itself...

udevadm info -a -n /dev/ttyUSB0

ROS 1 Noetic

source /opt/ros/noetic/setup.bash

cd ~/ros1_ws/src/
git clone git@github.com:ldrobotSensorTeam/ldlidar_ros.git

cd ldlidar_ros/
git submodule update --init --recursive -f

cd ~/ros1_ws/
rosdep install --from-paths src --ignore-src  -r -y
catkin_make --force-cmake -DCMAKE_BUILD_TYPE=Release

source devel/setup.bash

ROS 2 Foxy

source /opt/ros/foxy/setup.bash

cd ~/ros2_ws/src/
git clone git@github.com:ldrobotSensorTeam/ldlidar_ros2.git

cd ldlidar_ros2/
git submodule update --init --recursive -f

cd ~/ros2_ws/
colcon build --cmake-args -DCMAKE_BUILD_TYPE=Release --event-handlers summary+ status+ console_cohesion+ console_direct+ console_start_end+ console_stderr+

source install/setup.bash

Launch

ROS 1 Noetic

source /opt/ros/noetic/setup.bash
source /home/user/ros1_ws/devel/setup.bash

roslaunch ldlidar_ros ld19.launch
ld19.launch
<?xml version="1.0"?>
<launch>
  <arg name="laser_scan_topic_name"     default="scan"/>
  <arg name="point_cloud_2d_topic_name" default="pointcloud2d"/>
  <arg name="frame_id"                  default="base_laser"/>
  <arg name="port_name"                 default="/dev/ttyUSB0"/>
  <arg name="fix_to_base_link"          default="true" />

  <!-- LDROBOT LiDAR message publisher node -->
  <node pkg="ldlidar_ros" type="ldlidar_ros_node"
        name="ldlidar_publisher_ld19"
        output="screen">

    <param name="product_name"              value="LDLiDAR_LD19"/>
    <param name="laser_scan_topic_name"     value="$(arg laser_scan_topic_name)"/>
    <param name="point_cloud_2d_topic_name" value="$(arg point_cloud_2d_topic_name)"/>
    <param name="frame_id"                  value="$(arg frame_id)"/>
    <param name="port_name"                 value="$(arg port_name)"/>
    <param name="serial_baudrate"           value="230400"/>

    <!-- Set laser scan directon: -->
    <!--    1. Set counterclockwise, example: <param name="laser_scan_dir" type="bool" value="true"/> -->
    <!--    2. Set clockwise,        example: <param name="laser_scan_dir" type="bool" value="false"/> -->
    <param name="laser_scan_dir" type="bool" value="true"/>

    <!-- Angle crop setting, Mask data within the set angle range -->
    <!--    1. Enable angle crop fuction: -->
    <!--       1.1. enable angle crop,  example: <param name="enable_angle_crop_func" type="bool" value="true"/> -->
    <!--       1.2. disable angle crop, example: <param name="enable_angle_crop_func" type="bool" value="false"/> -->
    <param name="enable_angle_crop_func" type="bool" value="false"/>

    <!--    2. Angle cropping interval setting, The distance and intensity data within the set angle range will be set to 0 -->
    <!--       angle >= "angle_crop_min" and angle <= "angle_crop_max", unit is degress -->
    <param name="angle_crop_min" type="double" value="135.0"/>
    <param name="angle_crop_max" type="double" value="225.0"/>
    <param name="range_min" type="double" value="0.02"/>
    <param name="range_max" type="double" value="12.0"/>

  </node>

  <!-- publisher tf transform, parents frame is base_link, child frame is base_laser -->
  <!-- args="x y z yaw pitch roll parents_frame_id child_frame_id period_in_ms"-->
  <node name="base_to_laser_ld19" pkg="tf" type="static_transform_publisher"
        args="0.0 0.0 0.18 0 0.0 0.0 base_link base_laser 50"
        if="$(arg fix_to_base_link)"/>

</launch>

ROS 2 Foxy

source /opt/ros/foxy/setup.bash
source /home/user/ros2_ws/install/setup.bash

ros2 launch ldlidar_ros2 ld19.launch.py
ld19.launch.py
#!/usr/bin/env python3
from launch import LaunchDescription
from launch_ros.actions import Node

'''
Parameter Description:
---
- Set laser scan directon:
  1. Set counterclockwise, example: {'laser_scan_dir': True}
  2. Set clockwise,        example: {'laser_scan_dir': False}
- Angle crop setting, Mask data within the set angle range:
  1. Enable angle crop fuction:
    1.1. enable angle crop,  example: {'enable_angle_crop_func': True}
    1.2. disable angle crop, example: {'enable_angle_crop_func': False}
  2. Angle cropping interval setting:
  - The distance and intensity data within the set angle range will be set to 0.
  - angle >= 'angle_crop_min' and angle <= 'angle_crop_max' which is [angle_crop_min, angle_crop_max], unit is degress.
    example:
      {'angle_crop_min': 135.0}
      {'angle_crop_max': 225.0}
      which is [135.0, 225.0], angle unit is degress.
'''

def generate_launch_description():
  # LDROBOT LiDAR publisher node
  ldlidar_node = Node(
      package='ldlidar_ros2',
      executable='ldlidar_ros2_node',
      name='ldlidar_publisher_ld19',
      output='screen',
      parameters=[
        {'product_name': 'LDLiDAR_LD19'},
        {'laser_scan_topic_name': 'scan'},
        {'point_cloud_2d_topic_name': 'pointcloud2d'},
        {'frame_id': 'base_laser'},
        {'port_name': '/dev/ttyUSB0'},
        {'serial_baudrate': 230400},
        {'laser_scan_dir': True},
        {'enable_angle_crop_func': False},
        {'angle_crop_min': 135.0},  # unit is degress
        {'angle_crop_max': 225.0},  # unit is degress
        {'range_min': 0.02}, # unit is meter
        {'range_max': 12.0}   # unit is meter
      ]
  )

  # base_link to base_laser tf node
  base_link_to_laser_tf_node = Node(
    package='tf2_ros',
    executable='static_transform_publisher',
    name='base_link_to_base_laser_ld19',
    arguments=['0','0','0.18','0','0','0','base_link','base_laser']
  )


  # Define LaunchDescription variable
  ld = LaunchDescription()

  ld.add_action(ldlidar_node)
  ld.add_action(base_link_to_laser_tf_node)

  return ld