DART (Dynamic Animation and Robotics Toolkit) is an open-source, research-focused physics engine for robotics, animation, and machine learning. It provides transparent kinematics, dynamics, collision, and constraint-solving foundations for users who need more than a black-box simulator. DART uses generalized coordinates for articulated rigid body systems and Featherstone's Articulated Body Algorithm for accurate, stable motion dynamics.

• Research-grade dynamics — Featherstone algorithms, generalized coordinates, and direct access to dynamics quantities
• Easy to start — Python and C++ packages through common package managers, plus reproducible source builds with pixi
• Extensible foundations — Math, native collision, constraints, model loading, benchmarks, and tests that support new algorithms and baseline comparisons
• Unified model loading — Load URDF, SDF, and MJCF models through a single API
• Scalable compute roadmap — Cross-platform CPU support today, with roadmap work for multi-core, SIMD, and accelerator backends
• Battle-tested ecosystem — Powers Gazebo, research labs, and production systems worldwide, with best-effort support for production use

Python

import dartpy as dart

world = dart.World()

# Load a robot from URDF
urdf = dart.io.UrdfParser()
robot = urdf.parse_skeleton("dart://sample/urdf/KR5/KR5 sixx R650.urdf")
world.add_skeleton(robot)

# Simulate 100 steps
for _ in range(100):
    world.step()
    print(f"Positions: {robot.get_positions()}")

C++

The DART 7 C++ simulation facade is available in source builds while the final public header transaction is still in progress. Use the C++ API shape recorded in docs/design/simulation_cpp_api.md for current source-checkout examples; DART 6 C++ snippets remain on the release-6.* branches for compatibility-line users.

The quick-start snippets above target the current main branch and DART 7 API. Until DART 7 package artifacts are published, package managers resolve the latest published DART 6 artifacts instead, and different indexes may briefly serve different DART 6 patch releases until their packages finish publishing. Use the file-free package smoke checks below for the installed package version, or use the source checkout path for the DART 7 quick starts.

All distributions →

These snippets create a tiny model in code, so they do not depend on sample data files being present in the installed package.

Python package

import dartpy as dart

world = dart.simulation.World()
skeleton = dart.dynamics.Skeleton("box")
skeleton.createFreeJointAndBodyNodePair()
world.addSkeleton(skeleton)
world.step()
print(f"Positions: {skeleton.getPositions()}")

C++ package

The published C++ package smoke for the compatibility line is maintained on release-6.*. DART 7 C++ package smoke checks move through check-dart7-artifacts and the local source-checkout promotion gates until DART 7 C++ artifacts are published.

pixi install
# Smoke the Python-first DART 7 rigid-body demo surface.
pixi run py-demos -- --scene rigid_body --headless --frames 1

# Open the curated rigid-body GUI verifier.
pixi run py-demos
pixi run py-demos -- --scene rigid_solver_compare

# Capture docked visual evidence for the solver comparison.
pixi run py-demo-capture -- --scene rigid_solver_compare --frames 24 --width 960 --height 540 --show-ui

# Optional C++ World-only companion smoke.
pixi run demos -- --scene rigid_body --headless --frames 1

The full 36-row rigid-body visual verification workflow, Rigid Workflow search terms, and capture commands are in the Python demos README.

• Static Docs: English | 한국어
• AI Docs (experimental): DeepWiki for quick codebase Q&A | NotebookLM (Google account required)
• Questions: Ask in GitHub Discussions when you want maintainer or community input.

• Developer Onboarding Guide — Architecture, components, and workflows
• Contributing Guide — Style guide and contribution process
• Project Direction — Research-focused north star and priorities
• Living Plans — Active and proposed roadmap items
• Background Theory — Dynamics, contact solving, and mathematical foundations
• Gazebo Integration — gz-physics integration workflow
• Release Roadmap — Compatibility, deprecations, and future plans

• main — Active development targeting DART 7 (not yet production-ready)
• release-6.19 — Maintenance branch for DART 6 LTS (critical fixes only); see the DART 6 documentation

If you use DART in an academic publication, please consider citing this JOSS Paper:

@article{Lee2018,
  doi = {10.21105/joss.00500},
  url = {https://doi.org/10.21105/joss.00500},
  year = {2018},
  publisher = {The Open Journal},
  volume = {3},
  number = {22},
  pages = {500},
  author = {Jeongseok Lee and Michael X. Grey and Sehoon Ha and Tobias Kunz and Sumit Jain and Yuting Ye and Siddhartha S. Srinivasa and Mike Stilman and C. Karen Liu},
  title = {DART: Dynamic Animation and Robotics Toolkit},
  journal = {Journal of Open Source Software}
}

DART is licensed under the BSD 2-Clause License.