CLOiSim is a high-performance multi-robot simulator based on Unity 6. It dynamically builds simulated 3D environments and robots directly from SDFormat (SDF) description files.
CLOiSim was developed to address performance bottlenecks encountered with other simulators when loading multiple robots with complex sensor suites. By leveraging Unity's efficient rendering and physics pipelines, CLOiSim provides a scalable solution for large-scale robot simulation.
- SDF Parser: Utilizes sdformat-sharp as a Unity package for robust and comprehensive SDF 1.6+ specification parsing.
- Unity Implementer: Automated mapping of SDF elements to Unity's Visual, Collision, and Physics (ArticulationBody) components.
- Transport Layer: High-performance sensor data and control signal transport via ZeroMQ (NetMQ).
- Web Service: JSON-based simulation control and monitoring through a web interface.
Important
🚨 CLOiSim has been upgraded to Unity 6 (6000.5.3f1). Legacy versions based on Unity 2022.3 LTS are no longer maintained.
Warning
Warning
Ubuntu 24.04 LTS is required on Linux. The bundled AssimpNetter 6.0.5 native library requires newer GLIBC/libstdc++ and may fail to load on older distributions such as Ubuntu 20.04/22.04.
| Branch | CLOiSim Version | Unity Version | Status |
|---|---|---|---|
main |
5.4.x (Latest Release) | Unity 6 | Active — release snapshots |
develop |
5.4.x+ (Rolling) | Unity 6 | Active — ongoing development toward the next release |
release-5.3.14 |
5.3.x | Unity 6 | Not recommended (URT freeze) |
release-4.14.6 |
4.x.x | Unity 2022.3 LTS | Maintenance |
release-3.2.0 |
3.x.x | Unity 2021 | Legacy |
release-2.7.7 |
2.x.x | Unity 2020 | Legacy |
| Category | Feature | Status | Notes |
|---|---|---|---|
| Joints | Joint Control / Pose | ✅ | ArticulationBody based |
| LiDAR | 2D / 3D (URT ray tracing) | ✅ | Pattern-based (e.g., Livox) supported |
| Camera | Color / Multi / Segmentation | ✅ | Rasterization-based |
| Depth Camera | Depth / RealSense (IR1, IR2, VCSEL dot pattern) | ✅ | Rasterization-based |
| Inertial | IMU / GPS | ✅ | Gaussian noise models included |
| Other | Sonar / IR / Contact | ✅ | |
| Noise | Gaussian / Custom | 🚧 | Gaussian fully supported |
- Physics Engine: NVIDIA PhysX with Temporal Gauss Seidel (TGS) solver for enhanced stability.
- World Elements: Actors (animated characters), Lights, Heightmaps (DEM), Roads.
- Coordinates: Support for Spherical Coordinates.
- Rendering: URP-based high-quality visuals with specialized shaders for sensors.
CLOiSim uses a flexible plugin architecture to extend robot and world functionalities via SDF <plugin> tags. Plugin names are case-sensitive and should be specified in the filename attribute (e.g., <plugin name="actor_plugin" filename="libActorPlugin.so" />).
LaserPlugin: Publishes 2D or 3D LiDAR data.CameraPlugin: Publishes 2D color or depth image data.SegmentationCameraPlugin: Publishes semantic segmentation images and label info.MultiCameraPlugin: Publishes data from multiple color cameras.RealSensePlugin: Handles IR1, IR2, depth, and color data for RealSense sensors.MicomPlugin: Controls differential drive (2/4-wheeled) and self-balancing robots.JointControlPlugin: Controls joints and publishes joint status.GpsPlugin: Provides GPS position data in the world.ImuPlugin: Publishes IMU sensor data.SonarPlugin/IRPlugin: Publishes range data from Sonar or IR sensors.LogicalCameraPlugin: Publishes object detection and info within the camera view.ContactPlugin: Publishes contact sensor data.ActorPlugin: Adds character control functionality using Unity AI components.ParticleSystemPlugin: Enables Unity's particle systems.ClothPlugin/ClothGrabberPlugin: Handles cloth simulation and fingertip grabbers.
ElevatorSystemPlugin: Controls lifting and calling logic for elevator systems.GroundTruthPlugin: Retrieves precise information (position, size, velocity) for all objects.ActorControlPlugin: Centrally controls actors that have theActorPluginattached.MowingPlugin: Handles grass and mowing simulation.
- OS: Ubuntu 24.04 LTS or Windows 10+ (older Ubuntu 20.04/22.04 not supported)
- Graphics: Vulkan-capable GPU (NVIDIA RTX 20-series recommended)
- Unity: Unity Editor 6000.5.3f1 (if building from source)
- Release Binary: Download the latest Linux version.
- From Source: Refer to the Build Guide for detailed instructions.
Set the paths to your resources (models, worlds, media):
export CLOISIM_FILES_PATH="/path/to/sample_resources/media"
export CLOISIM_MODEL_PATH="/path/to/sample_resources/models"
export CLOISIM_WORLD_PATH="/path/to/sample_resources/worlds"# Standard mode
./run.sh cloisim.world
# Headless mode (Linux only)
./run.sh --headless --world cloisim.worldTo bridge simulation data to ROS 2, use the cloisim_ros package:
- Supports ROS 2 Humble & Jazzy.
- Launch the bringup node to start publishing sensor topics.
See scripts/README.md for detailed EditMode test runner usage and configuration.
CLOiSim provides a WebSocket interface for runtime interaction:
- Path:
ws://127.0.0.1:8080/{service-name} - Capabilities: Marker placement (lines, boxes, text), simulation reset, and more.
- Detailed Guide
- Full SDF specification compatibility.
- Programmable C++ plugin interface.
- Advanced sensor performance optimizations.
- Enhanced graphical fidelity and material support.
If you encounter any issues or have feature requests, please open an Issue.
감사합니다. Thank you!