Nori A3 description v0.1.1

Nori A3 robot description — v0.1.1

MODEL: Nori A3

A URDF/xacro description of the Nori A3 for simulation and visualisation.
Loads in Isaac Sim, MuJoCo, Gazebo, or anything that reads URDF.

Try it in the browser, no install:
https://lab.norirobotics.com/nori/model
Docs:
https://docs.norirobotics.com/guide/a3

CONTENTS
46 links, 45 joints (22 movable)
22 visual meshes, collision primitives, per-link mass
6.6 MB

WHAT TO TRUST
Kinematics — joint axes, limits, link transforms — are measured and verified
against hardware. Joint limits are tested on real units.

Mass is per-link and weighed, but the total is ~8.7% light
(18.3 kg modelled against 20.1 kg real): hubs, wiring and fasteners
are not modelled as their own links. Assumed distributed; scale by 1.096.

Inertia is approximate — each link is a uniform-density primitive. Not
suitable for torque-level sim-to-real.

The lift's joint limit (0.700 m) is an OPERATING CEILING, not
the stroke. The mechanism travels 0.720 m; the 50 mm reserve keeps the
carriage off the top stop and is what the real controllers command.

Camera positions are measured; aim angles are modelled but not yet verified
on hardware. Torso, neck and head masses are measured; their SHAPES are
placeholders.

Full detail in NOTICE.

IMPORT NOTES
Three joints use mimic — the lift's middle stage and both geared grippers.
These are the most common import casualty: if the lift's middle section does
not move at half the top's rate, or a gripper's second finger stays still
while the first closes, the mimic did not survive.

Isaac Sim: leave "Import Inertia Tensor" unchecked and let PhysX compute from
collision geometry — the tensors here are estimates. Collider type: convex
decomposition.

LICENSE
CC BY-NC-SA 4.0. Free for research and simulation, share-alike, NOT for
commercial use. Converting the model and publishing your conversion is
expressly fine. Commercial enquiries: info@norirobotics.com

Not open source in the OSI sense — the non-commercial term disqualifies it.
Please describe it as source available.