YDLIDAR ROS2 Driver

ydlidar_ros2_driver is a new ros package, which is designed to gradually become the standard driver package for ydlidar devices in the ros2 environment.

How to install ROS2

ubuntu

windows

How to Create a ROS2 workspace

Create a workspace

Compile & Install YDLidar SDK

ydlidar_ros2_driver depends on YDLidar-SDK library. If you have never installed YDLidar-SDK library or it is out of date, you must first install YDLidar-SDK library. If you have installed the latest version of YDLidar-SDK, skip this step and go to the next step.

Download or clone the YDLIDAR/YDLidar-SDK repository on GitHub.
Compile and install the YDLidar-SDK under the build directory following README.md of YDLIDAR/YDLidar-SDK.

Clone ydlidar_ros2_driver

Clone ydlidar_ros2_driver package for github :

git clone https://github.com/YDLIDAR/ydlidar_ros2_driver.git ydlidar_ros2_ws/src/ydlidar_ros2_driver
Build ydlidar_ros2_driver package :
```
cd ydlidar_ros2_ws
colcon build --symlink-install
```
Note: install colcon see

>Note: If the following error occurs, Please install YDLIDAR/YDLidar-SDK first.
Package environment setup :

source ./install/setup.bash

Note: Add permanent workspace environment variables. It's convenientif the ROS2 environment variables are automatically added to your bash session every time a new shell is launched:
```
$echo "source ~/ydlidar_ros2_ws/install/setup.bash" >> ~/.bashrc
$source ~/.bashrc
```
Confirmation To confirm that your package path has been set, printenv the grep -i ROS variable.
```
$ printenv | grep -i ROS
```
You should see something similar to: OLDPWD=/home/tony/ydlidar_ros2_ws/install
Create serial port Alias [optional]
```
$chmod 0777 src/ydlidar_ros2_driver/startup/*
$sudo sh src/ydlidar_ros2_driver/startup/initenv.sh
```
Note: After completing the previous operation, replug the LiDAR again.

Configure LiDAR paramters

ydlidar_ros2_driver_node:
  ros__parameters:
    port: /dev/ttyUSB0
    frame_id: laser_frame
    ignore_array: ""
    baudrate: 230400
    lidar_type: 1
    device_type: 0
    sample_rate: 9
    abnormal_check_count: 4
    resolution_fixed: true
    reversion: true
    inverted: true
    auto_reconnect: true
    isSingleChannel: false
    intensity: false
    support_motor_dtr: false
    angle_max: 180.0
    angle_min: -180.0
    range_max: 64.0
    range_min: 0.01
    frequency: 10.0
    invalid_range_is_inf: false

Run ydlidar_ros2_driver

Run ydlidar_ros2_driver using launch file

The command format is :

ros2 launch ydlidar_ros2_driver [launch file].py

Connect LiDAR uint(s).

ros2 launch ydlidar_ros2_driver ydlidar_launch.py

launch $(ros2 pkg prefix ydlidar_ros2_driver)/share/ydlidar_ros2_driver/launch/ydlidar.py

RVIZ

ros2 launch ydlidar_ros2_driver ydlidar_launch_view.py

echo scan topic

ros2 run ydlidar_ros2_driver ydlidar_ros2_driver_client or ros2 topic echo /scan

Launch file introduction

The driver offers users a wealth of options when using different launch file. The launch file directory

is "ydlidar_ros2_ws/src/ydlidar_ros2_driver/launch". All launch files are listed as below :

launch file	features
ydlidar.py	Connect to defualt paramters Publish LaserScan message on `scan` topic
ydlidar_launch.py	Connect ydlidar.yaml Lidar specified by configuration parameters Publish LaserScan message on `scan` topic
ydlidar_launch_view.py	Connect ydlidar.yaml Lidar specified by configuration parameters and setup RVIZ Publish LaserScan message on `scan` topic

Publish Topic

Topic	Type	Description
`scan`	sensor_msgs/LaserScan	2D laser scan of the 0-angle ring

Subscribe Service

Service	Type	Description
`stop_scan`	std_srvs::Empty	turn off lidar
`start_scan`	std_srvs::Empty	turn on lidar

Configure ydlidar_ros_driver internal parameter

The ydlidar_ros2_driver internal parameters are in the launch file, they are listed as below :

Parameter name	Data Type	detail
port	string	Set Lidar the serial port or IP address it can be set to `/dev/ttyUSB0`, `192.168.1.11`, etc. default: `/dev/ydlidar`
frame_id	string	Lidar TF coordinate system name. default: `laser_frame`
ignore_array	string	LiDAR filtering angle area eg: `-90, -80, 30, 40`
baudrate	int	Lidar baudrate or network port. default: `230400`
lidar_type	int	Set lidar type 0 -- TYPE_TOF 1 -- TYPE_TRIANGLE 2 -- TYPE_TOF_NET default: `1`
device_type	int	Set device type 0 -- YDLIDAR_TYPE_SERIAL 1 -- YDLIDAR_TYPE_TCP 2 -- YDLIDAR_TYPE_UDP default: `0`
sample_rate	int	Set Lidar Sample Rate. default: `9`
abnormal_check_count	int	Set the number of abnormal startup data attempts. default: `4`
fixed_resolution	bool	Fixed angluar resolution. default: `true`
reversion	bool	Reversion LiDAR. default: `true`
inverted	bool	Inverted LiDAR. false -- ClockWise. true -- CounterClockWise default: `true`
auto_reconnect	bool	Automatically reconnect the LiDAR. true -- hot plug. default: `true`
isSingleChannel	bool	Whether LiDAR is a single-channel. default: `false`
intensity	bool	Whether LiDAR has intensity. true -- G2 LiDAR. default: `false`
support_motor_dtr	bool	Whether the Lidar can be started and stopped by Serial DTR. default: `false`
angle_min	float	Minimum Valid Angle. default: `-180`
angle_max	float	Maximum Valid Angle. default: `180`
range_min	float	Minimum Valid range. default: `0.1`
range_max	float	Maximum Valid range. default: `16.0`
frequency	float	Set Scanning Frequency. default: `10.0`
invalid_range_is_inf	bool	Invalid Range is inf. true -- inf. false -- 0.0. default: `false`
More paramters details, see here

Contact EAI

If you have any extra questions, please feel free to contact us

nilutpolkashyap/ydlidar_ros2_driver