{
  "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_005.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_005",
  "rows": 763,
  "sides": [
    {
      "side": "left",
      "rows": 763,
      "npz": "/media/yxma/Disk1/twm/force_recovery/motherboard/2026-05-10/episode_005_left.npz",
      "force_calibration": "react_calib (calibration-free recon + gain field + clip correction)",
      "pipeline_version": 5,
      "n_contact_rows": 424,
      "no_contact_frac": 0.4442988204456094,
      "is_new_frac": 0.28833551769331583,
      "duplicate_rows_forward_filled": 543,
      "force_p50_n": 1.3931856155395508,
      "force_p95_n": 5.259615421295166,
      "force_max_n": 6.251071453094482,
      "force_p50_contact_n": 2.9424359798431396,
      "penetration_p50_mm": 0.6965928077697754,
      "penetration_p95_mm": 2.629807710647583,
      "penetration_max_mm": 3.125535726547241,
      "gel_max_depth_p95_mm": 0.5874930620193481,
      "gel_max_depth_max_mm": 1.0830680131912231,
      "identity_max_abs_dev": 0.0,
      "direction": {
        "usable": true,
        "v_dot_n_rise_mm": -3.2478576942818433,
        "v_dot_n_fall_mm": -1.454201117568116,
        "corr_dforce_vdotn": -0.09047358782818703,
        "n_rise": 118,
        "n_fall": 121
      }
    },
    {
      "side": "right",
      "rows": 763,
      "npz": "/media/yxma/Disk1/twm/force_recovery/motherboard/2026-05-10/episode_005_right.npz",
      "force_calibration": "react_calib (calibration-free recon + gain field + clip correction)",
      "pipeline_version": 5,
      "n_contact_rows": 286,
      "no_contact_frac": 0.6251638269986894,
      "is_new_frac": 0.28964613368283093,
      "duplicate_rows_forward_filled": 542,
      "force_p50_n": 0.0,
      "force_p95_n": 4.285294055938721,
      "force_max_n": 5.259615421295166,
      "force_p50_contact_n": 2.9424359798431396,
      "penetration_p50_mm": 0.0,
      "penetration_p95_mm": 2.1426470279693604,
      "penetration_max_mm": 2.629807710647583,
      "gel_max_depth_p95_mm": 0.7971731424331665,
      "gel_max_depth_max_mm": 0.9093713760375977,
      "identity_max_abs_dev": 0.0,
      "direction": {
        "usable": true,
        "v_dot_n_rise_mm": 3.7499645627611256,
        "v_dot_n_fall_mm": -1.6012164958931512,
        "corr_dforce_vdotn": 0.3095885814990277,
        "n_rise": 91,
        "n_fall": 66
      }
    }
  ],
  "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"
  ]
}