{
  "generator": "twm.force_recovery.export_force_columns",
  "stiffness_n_per_mm": 2.0,
  "penetration": "penetration_mm = force_normal_n / stiffness_n_per_mm  (ASSUMED stiffness)",
  "press_direction": "R(q_row) @ gel_axis_in_rigid from calibration/*/T_gel_to_rigid_<side>.json",
  "no_contact_rule": "force == 0 -> penetration 0 and target_pose is a copy of sensor_<side>_pose",
  "duplicate_rows": "tactile_<side>_is_new == False rows reuse the previous estimate (forward fill, asserted exact)",
  "source_release": "/media/yxma/Disk1/twm/release/motherboard/meta/2026-05-10/episode_001.parquet",
  "force_calibration": [
    "react_calib (calibration-free recon + gain field + clip correction)"
  ],
  "supersedes": "Exports before 2026-08-07 used a calibration that applied pixel-unit weights to mm-unit features (end-to-end rho 0.143, peak force 18.3 N). Those newton values are void; these come from react_calib (held-out rho 0.739, MAE 1.23 N, split by press position).",
  "task": "motherboard",
  "date": "2026-05-10",
  "episode": "episode_001",
  "rows": 7621,
  "sides": [
    {
      "side": "left",
      "rows": 7621,
      "npz": "/media/yxma/Disk1/twm/force_recovery/motherboard/2026-05-10/episode_001_left.npz",
      "force_calibration": "react_calib (calibration-free recon + gain field + clip correction)",
      "pipeline_version": 5,
      "n_contact_rows": 3093,
      "no_contact_frac": 0.594147749639155,
      "is_new_frac": 0.28303372260858156,
      "duplicate_rows_forward_filled": 5464,
      "force_p50_n": 0.0,
      "force_p95_n": 5.259615421295166,
      "force_max_n": 7.306922912597656,
      "force_p50_contact_n": 2.9424359798431396,
      "penetration_p50_mm": 0.0,
      "penetration_p95_mm": 2.629807710647583,
      "penetration_max_mm": 3.653461456298828,
      "gel_max_depth_p95_mm": 1.085529088973999,
      "gel_max_depth_max_mm": 2.814138650894165,
      "identity_max_abs_dev": 0.0,
      "direction": {
        "usable": true,
        "v_dot_n_rise_mm": 13.662031083333096,
        "v_dot_n_fall_mm": 7.159910793745246,
        "corr_dforce_vdotn": 0.19570888005623296,
        "n_rise": 1125,
        "n_fall": 954
      }
    },
    {
      "side": "right",
      "rows": 7621,
      "npz": "/media/yxma/Disk1/twm/force_recovery/motherboard/2026-05-10/episode_001_right.npz",
      "force_calibration": "react_calib (calibration-free recon + gain field + clip correction)",
      "pipeline_version": 5,
      "n_contact_rows": 1732,
      "no_contact_frac": 0.7727332371079911,
      "is_new_frac": 0.28277128985697414,
      "duplicate_rows_forward_filled": 5466,
      "force_p50_n": 0.0,
      "force_p95_n": 4.285294055938721,
      "force_max_n": 7.293209552764893,
      "force_p50_contact_n": 2.9424359798431396,
      "penetration_p50_mm": 0.0,
      "penetration_p95_mm": 2.1426470279693604,
      "penetration_max_mm": 3.6466047763824463,
      "gel_max_depth_p95_mm": 0.9505183100700378,
      "gel_max_depth_max_mm": 2.2311151027679443,
      "identity_max_abs_dev": 0.0,
      "direction": {
        "usable": true,
        "v_dot_n_rise_mm": 13.292071614534636,
        "v_dot_n_fall_mm": 13.728640289173756,
        "corr_dforce_vdotn": 0.02997737818629954,
        "n_rise": 657,
        "n_fall": 583
      }
    }
  ],
  "columns": [
    "force_left_normal_n",
    "force_left_penetration_mm",
    "force_left_target_pose",
    "force_right_normal_n",
    "force_right_penetration_mm",
    "force_right_target_pose"
  ]
}