# Recording setup This document describes the hardware and sensor configuration used to record the React dataset. Schema for the resulting `.pt` files is in [`schema.md`](schema.md). ## Collection method — robot-arm-free, human-hand operated React is recorded **without any robot arm**. A human operator holds one GelSight Mini sensor in each hand and performs the task directly. Compared to robot-collected manipulation data this means: - No robot kinematic constraints, no robot occluding the scene, no robot-specific visual features. - The tactile sensors move with natural human-hand dynamics — varied trajectories, jerks, regrasps, etc. - Cross-embodiment by design: any downstream policy / dynamics model trained on this data does not bake in a particular robot morphology. The trade-off: there are no robot joint angles or commanded actions in the data. Sensor 6-DoF pose comes from a motion-capture system (OptiTrack VRPN) tracking rigid-body markers rigidly attached to the back of each GelSight Mini, and a separate rigid body tracks the manipulated object (e.g. the motherboard). The dataset therefore does **not** include action labels and is **not** an imitation-learning / behavioral-cloning corpus. ## Sensors | Stream | Hardware | Native shape | Rate | |---|---|---|---| | 3 × RealSense color | Intel D415 (serials `143322063538`, `104122062574`, `217222066989`) | 480×640×3 uint8 (BGR) | 30 FPS | | 3 × RealSense depth | same | 480×640 uint16 (mm) | 30 FPS | | 2 × GelSight tactile | GelSight Mini (left / right, **handheld**) | 480×640×3 uint8 | ~25 FPS, resampled to camera ticks | | 3 × OptiTrack rigid bodies | `motherboard`, `sensor_left`, `sensor_right` | 7-vector (x, y, z, qx, qy, qz, qw) | ~120 Hz | Each RealSense camera's calibration is stored in the source repo under `twm/calibration/result/T_mocap_to_cam_{middle,left,right}.json`. The serial→position mapping: | Camera | Serial | Calibration file | Role | |---|---|---|---| | `cam0` | `143322063538` | `T_mocap_to_cam_right.json` | right-side view | | `cam1` | `104122062574` | `T_mocap_to_cam_left.json` | left-side view | | `cam2` | `217222066989` | `T_mocap_to_cam_middle.json`| overhead / center view | The OptiTrack-to-GelSight rigid transforms are stored alongside in `T_gel_to_rigid_{left,right}.json`. These let you project the GelSight contact center into any of the three camera views; see the per-recording GIFs under `figures/episode_previews/` for examples. ## Timing All streams share a common monotonic timestamp axis, recorded in the `timestamps` dataset (camera tick rate, 30 Hz). Per-tracker OptiTrack streams keep their own higher-rate timestamps under `optitrack//timestamps` in the raw HDF5 (not preserved in the processed `.pt` slice). The processed dataset (`processed/mode1_v1/...`) nearest-neighbor-aligns the OptiTrack pose stream to camera ticks. The full ~120 Hz pose track is only in the raw HDF5 mirror. ## Coordinate frames - OptiTrack reports positions in meters relative to the mocap room origin. - Quaternions follow `(qx, qy, qz, qw)` ordering (scalar last). - The `T_mocap_to_cam_*` extrinsics map mocap-frame coordinates into camera-frame coordinates (right-handed, +Z forward). ## Tasks recorded | Task | Description | |---|---| | `motherboard` | Bimanual manipulation of components on a computer motherboard (CPU placement, lever seat, screw tightening). | More tasks will be added as collection continues; see [`../tasks.json`](../tasks.json) for the machine-readable registry.