{
  "packet_dir": ".",
  "title": "Hulusi (葫芦丝) — Wooden Cucurbit Free-Reed Flute Family (HUL-001) — Build Packet",
  "instrument": "Hulusi (葫芦丝)",
  "build_target": "HUL-001 five-key wooden hulusi family",
  "artifact_focus": "F-key prototype ladder with B♭ / C / D / F / G family scaling",
  "release_status": "private review scaffold; L1_packet -> measurement_required",
  "packet_version": "v4.1 root scaffold + v4.4.8 studio explorer + Round 30 empirical-loop refresh",
  "hero_image": "images/hero-concept.svg",
  "scaffold_version": "v4.1",
  "scaffold_changes_from_v4": [
    "Master_Inputs sheet with 33 named globals (was: zero named ranges in udu)",
    "Six derived sheets — Acoustics / Pipes / Holes / Family / BOM / Validation (was: single sheet in udu)",
    "Family sheet is fully formula-driven (was: hand-typed static values in udu)",
    "Data validation dropdowns on key, gourd species, tube wood, reed material",
    "Cents-error formula auto-fills in Validation when measured Hz is entered",
    "SolidWorks global-var parity file (cad/hulusi-design-table.txt) makes the Excel ↔ SW link self-documenting"
  ],
  "generated": "2026-05-05",
  "files_included": [
    "README.md",
    "design.md",
    "hulusi-design-table.xlsx",
    "bom.csv",
    "sourcing.csv",
    "cut-list.csv",
    "validation.csv",
    "validation-loop.csv",
    "free-reed-empirical-loop.md",
    "p0-reed-coupon-log.csv",
    "p1-single-melody-pipe-control-log.csv",
    "windchest-geometry-plan.csv",
    "safety-gates.csv",
    "family-spec.csv",
    "assembly-manual.md",
    "drawing-brief.md",
    "visual-bom-brief.md",
    "supplier-rfq.md",
    "hulusi-starter.wl",
    "capstone-deck.md",
    "capstone-deck.pptx",
    "print-packet.md",
    "print-packet.pdf",
    "print-packet.html",
    "cad/hulusi_master.scad",
    "cad/hulusi-design-table.txt",
    "drawings/hulusi-section.svg",
    "drawings/hulusi-family-scale.svg",
    "drawings/reed-detail.svg",
    "site/index.html",
    "explorer.html"
  ],
  "design_table_stats": {
    "sheets": 7,
    "named_globals": 33,
    "formulas": 113,
    "formula_errors": 0
  },
  "family_keys": ["B♭", "C", "D", "F", "G"],
  "family_members": [
    "HUL-B♭",
    "HUL-C",
    "HUL-D",
    "HUL-F",
    "HUL-G"
  ],
  "prototype_ladder": [
    "HUL-P0 reed coupon",
    "HUL-P1 single melody pipe (F-key)",
    "HUL-P2 full F-key hulusi",
    "HUL-P3 waxable Drone 2",
    "HUL-P4 family molds/jigs"
  ],
  "deferred": [
    "Production CAD (.step / .stl / .dxf / .gcode) until HUL-P1 validates pipe physics",
    "Reed pull-down eigenvalue fit until HUL-P0 measured data exists"
  ],
  "empirical_loop": {
    "readiness": "L1_packet -> measurement_required",
    "scope": "HUL-P0 reed coupon and HUL-P1 single-melody-pipe control scaffolds only",
    "measurement_status": {
      "reed_alone_pitch_hz": "not_measured",
      "pull_down_cents": "not_measured",
      "onset_pressure_pa": "not_measured",
      "blow_draw_behavior": "not_measured",
      "coupled_pitch_hz": "not_measured",
      "leak_status": "unknown"
    },
    "primary_files": [
      "free-reed-empirical-loop.md",
      "p0-reed-coupon-log.csv",
      "p1-single-melody-pipe-control-log.csv",
      "validation-loop.csv",
      "windchest-geometry-plan.csv",
      "safety-gates.csv",
      "family-spec.csv"
    ]
  },
  "release_gate": {
    "public_candidate": false,
    "required_before_public": [
      "HUL-P0 reed-coupon measurements are still required before claiming reed pull-down calibration.",
      "HUL-P1 melody-pipe measurements are still required before treating the pipe and finger-hole model as validated.",
      "Production CAD, DXF, STEP, STL, and G-code remain deferred until measured prototype data supports them.",
      "Concept images should be replaced with shop photos before public-release presentation."
    ]
  },
  "engineering": {
    "wolfram": [
      {
        "source_file": "hulusi-starter.wl",
        "cloud_path": "hulusi-starter.wl",
        "cloud_url": "",
        "kind": "local-wl",
        "permission": "local-only pending cloud publish"
      }
    ]
  },
  "cultural_provenance": {
    "claim": "The hulusi lineage is credited to the Dai people of Yunnan, with related instruments across nearby communities and regions; this repo documents a modern wooden workshop interpretation rather than a traditional artifact claim."
  },
  "sources": [
    "README.md",
    "design.md",
    "validation.csv",
    "risks.md",
    "site/index.html"
  ],
  "notes": [
    "All dimensions in the workbook and SCAD are imperial inches.",
    "Reed K_imperial = 27,300 is computed from brass C26000 published moduli; verify on HUL-P0.",
    "Modern Western 'all-closed = tonic' convention used; traditional Dai voicing reachable by adjusting key_midi to tonic_MIDI - 5."
  ]
}