ghkim-rlwrld/shell_game_joint_global

shell_game — joint actions, global instruction

Cups hide a red block, the cups are shuffled by hand, and the arm lifts the cup the block ended under and drops it in a basket. 45 episodes, 18,442 frames.

Absolute joint targets, 8-dim. Every frame carries the same sentence: Find the cup hiding the block after the swaps and move it into the basket.

This is the only one of the three whose action space the DROID runtime already speaks.

Converted from the recorder's DROID-schema teleoperation.h5, one episode per directory, with the videos re-encoded all-intra. The raw h5 is the source of record and lives at ghkim-rlwrld/shell_game; anything that needs a different action representation or a fresh label pass has to go back to it, not to this tree.

Cameras are three stereo pairs and only the left eye is shipped here, which is what a policy reading three streams actually loads:

11845904  wrist        looks down over the gripper
37149196  cam_ext_left   external, to the robot's left
34022131  cam_ext_right  external, to the robot's right

Control rate is 9.2 Hz measured. The mp4 containers say 10 fps and are wrong.

Naming

<task>_<action space>_<language>. An earlier set of names took the action space from one dataset and the language from another, so they could not be compared side by side.

	action	language
shell_game_joint_global	7 joints + gripper (8)	one sentence per episode
shell_game_eef_global	delta EEF, xyz + rot6d + gripper (10)	one sentence per episode
shell_game_eef_subtask	delta EEF (10)	per-frame subtask
solve_equation_eef_subtask	delta EEF (10)	per-frame subtask

Why rot6d and not rpy

This recorder's roll sits at +-pi and flips sign 269 times across the 45 shell_game episodes. Regressing the raw angle puts a 2*pi step in the target at every flip. Unwrapping and moving to the first two columns of the rotation matrix leaves 0 discontinuities and takes the roll channel from std 3.08 to 0.039. The delta mask is (9, -1): position and rotation relative to the current state, gripper absolute.

A runtime that wants 7-dim xyz+rpy can recover it exactly — Gram-Schmidt the two 3-vectors, take the third by cross product, then as_euler("xyz"), verified to 4.44e-16 over 41 episodes. Doing that at inference is safe; training on rpy is not, for the reason above.