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Alloy

A physics engine for robot learning: robots, cloth, liquids and cables in one scene, in many worlds on one GPU.

pip install alloy-engine

import alloy

scene = alloy.Scene(dt=0.01)
scene.add_ground()
scene.add_box("table", size=(0.6, 0.6, 0.4), pos=(0, 0, 0.2), static=True)
scene.add_box("block", size=(0.05, 0.05, 0.05), pos=(0, 0, 0.6), mass=0.2)
sim = alloy.build(scene)
sim.run(1.0)
print(sim.state(world=0)["block.pos"].round(3), sim.check()["ok"])
sim.render(width=640, height=480, path="block.png")

[0.    0.    0.425] True

The block falls 17.5 cm, lands on the table and rests with its centre at 0.425 m. True means every world passed its health checks.

Where next

  • Quickstart: your first simulation and image, step by step.
  • Use Alloy with your coding agent: one prompt to paste, and what to ask for.
  • Guides: Robots, Train with RL, Imitation learning, Camera, Liquids, Cloth, Cables, World health.
  • Errors and fixes: what each error means and what to change.
  • Known limits: what does not work yet, one line each.

Alloy is built on Newton, MuJoCo Warp and Warp. It runs on an NVIDIA GPU, or on the CPU when there is none.