URoboSim

Unreal engine based robot simulator.

Version using SDF for loading robots. See gzsdf for converting URDF to SDF.

Plugin Dependencies

• UUtils
• UROSWorldControl
• UROSBridge
• URoboVision

Installation

• place the URobosim into the plugin folder of your project
• place all plugin dependencies into the plugin folder of your project
• add URoboSim as dependency to the *.Build.cs

ROS requirements

• install ROS (tested on kinetic)
• install rosbridge_suite
• add urobosim_msgs to your workspace

Tools

• Github Organization
• Msg Generation
• Action Generation
• ROS configuration Example

Setup Editor

• open Editor Settings
• search for CPU
• disable "Use less CPU when in Background"

Importing new Robot Model

• convert xacro to urdf: rosrun xacro xacro --inorder -o model.urdf model.urdf.xacro

• convert urdf to sdf: gz sdf -v 1.6 -p /my_urdf.urdf > /my_sdf.sdf

• replace ' with ": sed -i "s/'/\"/g" my_sdf.sdf

• convert .stl and .dae files to .fbx

  • you can use this blender script (experimental state) FBX conversion

• Source ROS environment before starting UE4.

  • Currently only ros python tool "catkin build" supported (catkin_make creates different ROS_PACKAGE_PATH which unreal uses to finds all ros packages)

• Start unreal

• Create Collision channel Robot in new Projects

• Click import

• Select sdf
• Tick combine meshes
• Click ImportAll (if first mesh does not include textures the rest will be loaded without texture. Workaround: click import until mesh with texture is imported)

• Drag and drop the created asset into the world (while dragging wait for the mesh creation to be finished before dropping the model)

Setup GameInstance

• Create Blueprint of RoboSimGameInstance or adjust URoboSimGameInstance of the URoboSim Content

• Open the Project Settings (Edit > ProjectSettings)

• In Maps & Modes set
  • Default GameMode to GameMode
  • GameInstance to the RoboSimGameInstance

Add Controller

• create new data asset, right click into ContentBrowser > Miscellaneous > Data Asset

• search for RControllerDataAsset

• double click on the created asset
• add robot name and controller configurations
• drag and drop the config file into the world

Add ROSCommunication

• create new data asset, right click into ContentBrowser > Miscellaneous > Data Asset
• search for RROSCommunicationDataAsset

• double click on the created asset
• add robot name and communication configurations
• drag and drop the config file into the world

FQA

• The robot in dynamic mode wobbles/moves strange
  • Unreal has problems with long kinematic chains
  • Try optimizing the joint controller parameters
  • Try small changes in joint space large changes might lead to overswinging