unity_ros_lidar_3d

Unity package for simulating 3D Laser Scanner (LIDAR) and publishing the point cloud to ros2.

This package implements following things

A simple robot with 4 wheels

• A simple urdf file is created (along with xacro). This urdf file is imported to unity using urdf importer.
• A differential drive robot controller is implemented in unity. This subscribe to "cmd_vel" topic and generate commands for movement of robot in unity.

LIDAR (3D laser Scanner)

• A 3D laser scanner sensor is implement using Ray Casting. It has parameters such as fov, angular_resolution (both horizontal and vertical), min_range, max_range etc.
• A Point Cloud publisher publish the generated point cloud to 'point_cloud' topic. It aslo publish the pose (position and orientation) of the laser_scanner to 'laser_scan_pose'.

Notes

• This package is in ROS2 meaning unity scripts in this are written for ROS2, so if you will select ROS1 in unity (in ROS-TCP-Connector) it will show compilation error. By default ROS2 is selected but if you want to run this in ROS1 you have to modify scripts accordingly.
• Please do read how unity-ros framework works. ROS Unity Hub ROS Unity Integration
• User can edit xacro file and then generate urdf from it. And import new urdf into the unity to try different robot.
• User can edit all parameters either from unity script or from panel.

Installation and Running

• Read ROS-Unity integration (try few examples to get the grasp on ros-unity framework works in general). ROS Unity Hub ROS Unity Integration

Installation

• Download this package and open in unity.
• Create a ros workspace and build package ROS-TCP-Endpoint in the workspace by downloading approriate branch (ROS or ROS2 Branch of ROS-TCP-Endpoint ) from github.
• Install teleop-twist-keyboard package to control robot using keyboard
  • sudo apt-get install ros-noetic-teleop-twist-keyboard change the ROS-DISTRO name from neotic to your ROS-DISTRO

Running

• Run ROS-TCP-Endpoint Server in one terminal ROS–Unity Demo Setup
  • ROS1: roslaunch ros_tcp_endpoint endpoint.launch
  • ROS2: ros2 run ros_tcp_endpoint default_server_endpoint
• Click on play button in unity to start the simualtion
• Run rviz in another terminal and add tf and point cloud topics to rviz for displaying them
  • ROS1: rosrun rviz rviz
  • ROS2: rviz2
• Run teleop_twist_keyboard in another terminal and control the robot using keyboard
  • ROS1: rosrun teleop_twist_keyboard teleop_twist_keyboard.py
  • ROS2: ros2 run teleop_twist_keyboard teleop_twist_keyboard

Credits

• Most of the code is from Navigation 2 SLAM Example. Following addition/modifications are made
  • Laser scanner code to make it scan in 3D as well as fast and publish point cloud message.
  • AGVController script has been modified and renamed as Robot Controller to control 4 wheel robot instead of 2.