Workcell and frames
For a plain description of the shelf, tray, and arm layout (with schematics and 3D), start with the Introduction. This page is the frame contract: how names, stamps, and surveyed YAML stay consistent across description, perception, planning, and placement.
Coordinate frame tree · world (metres, REP-103)
Both branches start at world. Arrows show ancestry; grouped siblings do not form a chain.
Robot branch
rail_base → carriage → base_linkprismatic rail + UR10e root
shoulder_link → … → wrist_3_link → tool0official ur_description chain
tool0 children: gripper · wrist_camera_linkgripper → grasp_center / fingers; camera → optical frame
Shelf branch
shelfstatic world → shelf transform
Separate children of shelf
lane_01 … lane_06six sibling frames · +Y downhill
roller_bedfixed shelf child
overhead_camera_linkfixed shelf child
overhead_camera_optical_framechild of camera link · image stamps
RootStructureKinematics / sensorsEnd-effector
Surveyed geometry
Lane frames and collision volumes come from one YAML source so semantic IDs cannot drift from TF names:
restocker_description/config/workcell_geometry.yamlrestocker_description/config/gripper_geometry.yaml
Lane frames are axis-aligned to shelf. Roller-bed inclination is evaluated as geometry, not as
a rotated frame. Grasp planning targets grasp_center; MoveIt solves to tool0. Viewpoints are
poses of wrist_camera_optical_frame, converted to tool0 via the mount transform from TF.
Rules that keep the tree consistent
- Units: metres / radians (REP-103 / REP-105 vocabulary).
- Store authoritative object poses in
world. - Transform observations at the acquisition stamp, never “latest.”
- Never invent identity transforms to paper over missing frames.
- Image topics stamp optical frames (
gz_frame_id), not body links.
This project
| Topic | Path |
|---|---|
| Robot / workcell Xacro | restocker_description/urdf/ |
| Geometry YAML | restocker_description/config/workcell_geometry.yaml |
| MoveIt groups | restocker_moveit_config/config/restocker.srdf |
References
- Literature: REP-103 · REP-105
- Official docs: TF2 (Jazzy)
- This project: Fundamentals: manipulators