# Unitree H2 and B2-W — actuator cutaway studies

Two GLB assets for the APRUMO humanoid and legged robotics application area. The robot surfaces come from Unitree's official simulation meshes. Pale blue translucent surfaces and fine blue contours reveal newly created dark actuator illustrations.

## Files

- `assets/unitree-h2-actuator-cutaway.glb` — H2 humanoid, with illustrative drives at all 31 source hinge joints.
- `assets/unitree-b2w-actuator-cutaway.glb` — B2-W wheeled quadruped, with illustrative drives at all 16 source hinge joints, including four wheel hubs.
- `viewer.html` — self-contained interactive preview. Includes both models and the viewer libraries; no CDN requests are required. Rotate, zoom, change body opacity, isolate drive families, select an actuator, focus a joint, or download either GLB.
- `previews/` — studio PNG renders of both models and the individual robots.
- `source/unitree-actuator-cutaways.blend` — editable Blender 3.6 scene with both robots, link hierarchy, materials, and individually named actuator assemblies.
- `source/source-provenance.json` — source file checksums and repository provenance.
- `manifest.json` — dimensions, joint names and axes, display poses, file checksums, and mesh statistics.
- `licenses/` — the full Unitree BSD 3-Clause notice and Three.js MIT notice.

The viewer was checked through a local HTTP server in a Chromium browser. A browser with WebGL is required. If your browser restricts locally opened HTML, serve this folder through a local preview server.

## Geometry and actuator interpretation

The shell geometry, link offsets and joint axes derive from Unitree's MJCF models. Collision proxies are omitted. Surface tessellation is simplified, source seams are welded where appropriate, and the robots are posed for display. The mesh remains recognizably Unitree H2 or B2-W.

The dark assemblies are new illustrative geometry: annular motor housings, copper winding ends, output bearings, hollow shafts, fasteners, seals and connectors. Larger leg drives, compact arm reduction housings, small wrist/ankle/neck drives, waist drives and wheel hubs have different proportions. Their dimensions and internal arrangements are visual concepts, not verified Unitree internals or qualified APRUMO products. The joint reference point and axis follow the source model; an actuator body can be offset along that axis for visual placement.

The H2 hand surfaces are included as provided by Unitree. Fingers are not individually rigged or populated with separate finger actuators. The GLBs are static posed scenes with a named link hierarchy, not simulation-ready rigs, motion animations or manufacturing CAD.

## Website use

The GLBs use metres, glTF's Y-up convention and ordinary PBR materials with alpha blending. Transparency and contour geometry are embedded in the assets. They have no baked background, floor, camera, light or external texture dependency. A light blue or neutral light studio environment gives the best contrast.

Load the separate GLBs on demand on the production site. The self-contained viewer embeds both files and is intended for review; it is larger than a production page that loads one model at a time. Renderer lighting and transparency settings can affect the appearance. For translucent surfaces, disable depth writing if your viewer does not do so automatically.

Keep the Unitree licence notice with the distributed assets and reproduce it in the website's third-party notices. Suggested caption:

> Unitree H2 / B2-W reference geometry. Added actuators are illustrative; no supply relationship or endorsement is implied.

Use the manufacturer's model names for identification. The assets do not establish a relationship between Unitree and APRUMO or show that APRUMO supplies these robots. The live APRUMO site has not been modified by this deliverable.

## Source and licences

Source: https://github.com/unitreerobotics/unitree_mujoco

Pinned revision: `1eb6642e3f3fdfb7fb13a9794fd6a2dd93ea0e7d`

Source folders: `unitree_robots/h2/` and `unitree_robots/b2w/`.

Unitree's source geometry is distributed under the BSD 3-Clause licence. See `licenses/UNITREE-BSD-3-Clause.txt` for its complete copyright, conditions and disclaimer. Three.js is distributed under the MIT licence in `licenses/THREE-MIT.txt`. Materials, contours, illustrative actuator assemblies and presentation were added for this APRUMO application study. This package does not grant trademark rights or imply manufacturer endorsement.