CL_Assets

A directory of assets H12 assets for the correll lab

mujoco_assets/battery/ — battery workcell (RoboCasa sim --task Battery)

• battery_cell.xml — the arena: ARPA cell, battery pack, a row of 36 free-joint screws, walls, floor, lights. No robot; h1_robocasa/battery_env.py builds it around the robosuite H1-2. Loads standalone in view_mjcf.py.
• meshes/ — battery and screw-head meshes used by the arena.
• objects/*.xml — parts placed in the scene. Every file here is merged into the task, so adding a part means adding a file.

Adding an object

Write a standalone MJCF that opens on its own in view_mjcf.py, with one top-level body per part (give it a <freejoint> to make it loose). Examples: objects/orange_fuse_block.xml, objects/hv_busbar_a01.xml.

• The body pos is its world spawn pose. Battery module tops are at z = 0.932 m, the screw-row walls at 0.91 m and the channels between modules at 0.822 m.
• Only the top-level bodies and the assets they use are merged. A floor, lights and <option> for viewing the file on its own can stay; the task skips them.
• Degree or radian angles and <default> classes both work. Mesh and texture files resolve against the file's own meshdir / texturedir.
• Mass and inertia are taken from the file compiled on its own, so the part weighs what it does in view_mjcf.py.
• The sim's viewer and cameras draw geom groups 1-2 only; a geom with no group is group 0 and invisible there. Put visible geoms in group 2 (they still collide), as hv_busbar_a01.xml does through its default class.
• Names (bodies, geoms, joints, materials, meshes) must be unique across the whole scene.
• objects/make_meshes.py builds the fuse block's visual mesh.

g1/ — the Unitree G1's model (GOLEM's golem_ros2_models and the G1 sim)

The G1's model source for GOLEM, the counterpart of meshes/h1_2 and ros_assets/ for the H1-2.

• g1/g1_description/ — the 29-DoF G1 as URDF and MJCF, body-only (g1_29dof_rev_1_0.*, rubber hands) and with the Dex3-1 hands (g1_29dof_with_hand_rev_1_0.*), and meshes/ (51 STL). meshdir="meshes" in the MJCFs and meshes/<name>.STL in the URDFs resolve inside this directory.
• g1/dex3_1_description/ — the standalone Dex3-1 hands (dex3_1_{l,r}.{urdf,xml}, scene.xml, meshes/ with 16 STL).
• g1/README.md — the provenance of these files, file by file.
• g1/LICENSE.unitree_ros — their licence (BSD-3).

Source: the leprechaun_g1 repo at 3bee054, which vendored unitreerobotics/unitree_ros at ccfc6fd. The files are byte for byte upstream's, except the Dex3 MJCFs (g1/README.md lists what changed). All meshes are Git-LFS objects (*.STL).

The G1's sphere model and SRDF

g1/g1_sphere.urdf and g1/g1_sphere_collision.srdf are the G1's self-collision model, supplied by the lab and not generated in this repo (there is no exclude_pair script for them). They sit beside g1_description/ because they are the lab's files, not Unitree's. The SRDF is the lab's file as supplied; the sphere model is the lab's except for its three torso spheres.

• g1_sphere.urdf packs 24 spheres (each as both collision and visual geometry, no meshes) onto the body-only G1, with its joints in /lowcmd slot order. It was packed on the rubber-hand G1: each hand is two spheres on a {left,right}_rubber_hand link at the Dex3 palm's mount, so the Dex3 fingers are not covered.
• The torso spheres are a column on the torso's midplane, fitted by an optimiser (differential evolution) against points sampled on g1_description's torso mesh, then rounded to millimetres: at torso-link z 0.061, 0.116 and 0.212 m, radii 0.078, 0.086 and 0.102 m. The fit minimised the mesh left uncovered, then the spheres' protrusion past the mesh, subject to every arm sphere clearing them by at least 25 mm at golem_upper_ik's home, t_pose and arms_front_45. With the arms hanging at golem_upper_ik's home, each upper arm is 9 mm from the real torso's flank. The lab's torso spheres (one around the lower torso, r 0.100 m, and two side by side around the chest, r 0.089 m) followed the flanks, so the shoulder-yaw spheres sat 2 mm from them there and the IK's keep-out (controller.d_min) could be no more than 2 mm. The column's sides stay 6 to 19 mm inside the flanks from the waist to the chest (torso z 0.04 to 0.16 m), so at home every arm sphere clears the torso by 25 mm and the G1 keeps the H1-2's 20 mm keep-out: an upper arm rolled inward from home stops a few millimetres from the real torso. Elsewhere the column follows the torso about as closely as the lab's spheres: the torso mesh lies at most 25 mm outside it (the lab's spheres: 22 mm), more than 20 mm only on those flanks, and the column stands up to 22 mm proud of the chest's front.
• g1_sphere_collision.srdf lists the collision pairs to skip. Unlike the H1-2's, it keeps the pelvis and hip-pitch spheres active against the torso, the arms and the hands. With the arms straight down (golem_upper_ik's arms_down) the real wrists and hands rest on the hips, so that pose is in collision on the meshes as in the spheres.
• The lab's original sphere model is g1/g1_sphere.urdf at commit f183096 (sha256 981f84fc823d8a9fd0aebcf126379935f7748125e2e8289758af6e5e6318cb57): git show f183096:g1/g1_sphere.urdf.