PointCloud Concatenator

This package is created to take more than one of LIDAR poincloud stream as ROS2 subscriber then, transform their frames given with static_transform_publisher tf2, and hence concatenate the input streams to output stream publisher.

Installation

If not installed, install ROS2 with distrubution you want. (Foxy and Humble is tested.)

Then, install this package and build as below:

mkdir yildiz_ws/src -p && cd yildiz_ws/src
git clone https://github.com/yusufy1ld1z/point_cloud_concatenator.git
cd ..
source /opt/ros/<your_distro>/setup.bash
colcon build

Then, source the local_setup

source ./install/local_setup.bash

Usage

Run Static Transforms

Open 3 terminals to run tf2 static_transform_publisher
For the usage of static_transform_publisher:

source /opt/ros/<your_distro>/setup.bash
ros2 run tf2_ros static_transform_publisher --help

On each one of the terminals, source the ROS2

source /opt/ros/<your_distro>/setup.bash

In terminal1:

ros2 run tf2_ros static_transform_publisher 0 0.56362 -0.30555 1.575  0.71 -0.02 base_link velodyne_left

In terminal2:

ros2 run tf2_ros static_transform_publisher 0 -0.56362 -0.30555 -1.580 0.71 -0.01 base_link velodyne_right

In terminal3:

ros2 run tf2_ros static_transform_publisher 0.0 0.0 0.0 1.575 0.0 0.0 base_link velodyne_top

You can edit the transformation values and frame_id's as you desired.

Download Bag and Play

You can download the sample bag record by this link.

Then extract the file to any folder and play it

ros2 bag play -l assignment_bag_0.db3

Run the Node

Now, run the point_cloud_concatenator in which the terminal you sourced the local_setup.bash

ros2 run point_cloud_concatenator pc_concatenate

Visualize

You can simply open rviz2, and change the fixed_frame to base_link, then add the topic "/sensing/lidar/concatenated_point_cloud".

rviz2

Images

The output frame_tree and rviz2 shots of the static_transform_publisher

The image of the not concatenated pointcloud streams

And the result poincloud stream of the point_cloud_concetanator on rviz2

License

MIT