cafe_xense

cafe_xense contains four robotic manipulation tasks, 110 complete trial episodes, and 120,321 joint-reference timesteps. Each episode includes seven arm joint states, one gripper joint state, head and wrist RGB images, and two Xense tactile pads with RGB, depth, and three-component force-grid observations.

The data is exported to the FTP-1-compatible Zarr structure for Open-X-Tactile. See the FTP-1 data-processing specification and ZARR_STRUCTURE.md for field definitions.

Release status

Data license, release version, contributor contact, and publication references remain to be confirmed. No license is assigned by this draft.

All 110 complete episodes are retained in the intended upload. The 69 visual-QC Warnings remain pending human review; this is not a claim that all episodes have passed every quality check.

Files

README.md
ZARR_STRUCTURE.md
dataset_mapping.json
task_instructions.json
manifest.json
task1/task1.zarr.zip
task2/task2.zarr.zip
task3/task3.zarr.zip
task4/task4.zarr.zip

Each archive contains its corresponding taskN.zarr/ directory. Download and extract the archives without changing the internal Zarr layout. Archive sizes and SHA-256 checksums are listed in manifest.json. Every archived member has been checked against its source SHA-256 and ZIP CRC.

Tasks and episodes

Task	Episodes	Timesteps	Instruction
task1	48	81,305	Pull the hard drive out of the server.
task2	8	6,864	Trials 1–4: take the bulb out of the tape roll and place it on the table. Trials 5–8: place it into another tape roll.
task3	26	14,432	Pick up one marker pen and place it in the clear plastic box.
task4	28	17,720	Move the pipe clamp from the left table to the right table.
Total	110	120,321

An episode spans one original trial from beginning to end, without trimming. Original trial numbers may have gaps. Episode indices within each task start at zero and must not be inferred by subtracting one from the original trial number.

Robot and camera mapping

• right_arm_joints (T,7): source Data1–7, in radians. Data1 is base left/right rotation; Data2–7 are the arm joints ordered from base to wrist.
• right_hand_joints (T,1): source Data8, the raw gripper angle in radians. right_hand_joints_idx is 28. Each trial starts with the gripper open.
• camera_ego_rgb (T,224,224,3): top/head camera, from arm4_gripper_usb_camera_stream_compressed.
• right_wrist_camera_rgb (T,224,224,3): wrist camera, from arm4_top_usb_camera_stream_compressed.

The right_* namespace represents one exported arm and gripper. It does not mean that both tactile sensors are on the right finger. The camera key alone does not establish ego/UMI classification or calibrated world-frame poses.

Tactile mapping

Both pads belong to the same gripper. For all three tactile groups:

Channel	Finger	Sensor serial	Functional area
0	Left	OG000470	0
1	Right	OG000144	1

• right_tactile_data_gripper (T,2,224,224,3): uint8 RGB images.
• right_tactile_data_depth (T,2,175,100): signed int16 raw counts.
• right_tactile_data_force_grid (T,2,35,20,3): signed int16 raw counts.
• Numeric validity masks, sensor names, modality types and area indices are retained. The exported sensor name is Xense; an exact product model is not asserted.

Force units and component ordering/frame are unverified. Do not interpret raw force counts as Newtons. Display heatmaps are scaled previews, not the stored numerical data and not evidence of physical force saturation.

Timing and episode boundaries

Joint timestamps provide the reference timeline. Other streams are matched by nearest MCAP log time within the same trial. The previously verified maximum absolute matching offset is 28.9383 ms. This does not establish hardware capture synchronization or independent new sensor acquisitions at every timestep.

meta/episode_ends contains exclusive cumulative episode ends. For episode e, use [0, episode_ends[0]) if e=0, otherwise [episode_ends[e-1], episode_ends[e]). Original trial identifiers and source provenance are stored in meta/; matched stream indices/timestamps/offsets are stored in auxiliary/.

Quality-check status

• All four Zarr stores passed the OXT metadata/structure checks, with no dataset-level structural errors or warnings. Human-authored publication metadata remains incomplete.
• Direct Codex visual review covered all 110 episodes and 330 prepared montage pages: 41 Pass, 69 Warning, 0 Fail. No external VLM API was called. These are sampled visual assessments, not calibrated probabilities or full-frame validation. Organizer acceptance of this review method remains to be confirmed.
• The contributor confirmed successful bulb placement in task2/trial_6 and task2/trial_7. Earlier incorrect task-failure findings were withdrawn.
• Additional source-joint reviews found constant-value intervals with visible wrist/finger motion or ambiguous boundary motion. Source CSV values match the export; the cause remains under review. Separate joint concerns also exist for task1/trial_12 and trial_39, whose main visual status remains Pass.
• Real-coordinate 4D validation is not complete. Verified wrist/camera poses and kinematic calibration are not available; joint curves do not substitute for that validation. Ego/UMI applicability remains unresolved.

The organizer metadata/example package is prepared separately from these full data archives.

Verified archives

Task	Archive size (GiB)	SHA-256
task1	31.320	2db944ce7c4b7e9e55984682f0d159f4fd0bf4939262d5c6e17521edea224743
task2	2.633	8a5c16ec8c0de35ae36862d864f4cc074c5c0ab2002cc926745438d1c5145cbf
task3	5.466	9beee703670c8e4da8adb475afee4ee0e524c620add1ac6874d5765c2922bdaf
task4	6.749	6c92842fe9da800ab70dcfd51b17f95713f590af65d1a0d7c66bb8412c6d29a7