H-Point: Package Builder

H-Point: Package Builder, What's New: v1.6.2 to v1.7.1

Curb Industries, INC. · July 2026

If you're upgrading straight from v1.6.2, here's everything you're getting in one jump: the v1.7.0 accuracy release plus the v1.7.1 patch.

The headline: standards accuracy

Referencing SAE J826 (1995) and the full SAE J941 (2002) eyellipse model, this is the biggest accuracy update yet.

• The 95th percentile manikin now matches SAE J826 Table 1 exactly, right down to the corrected 456.0 mm thigh length. Knee, ankle, heel, and ball of foot all shift slightly downstream to match.
• Planted feet. The ball of foot stays on the pedal as seat height changes, and the heel stays on the floor, the way a real driver's does. The thigh angle is now solved from the leg, not locked to the torso.
• Full SAE J941 (2002) driver eyellipse: correct 95th percentile axes (206.4 x 60.3 x 93.4 mm), a 12 degree side view tilt, and a placement derived from your own package geometry (pedal reference point, steering wheel position, seat height, and heel height) instead of a fixed formula. Short track packages (133 mm of seat travel or less) automatically switch to the shorter 173.8 mm axis.
• Vision lines now touch the tilted eyellipse at the exact tangent point.
• New rear view eyellipse cross section at the centroid.

Expect the eyellipse position and shape to visibly change from v1.6.x. That's the standard catching up, not a bug.

New: seating layout options

• 3 Across Seating adds a third, centerline occupant to any row with one toggle. No door or steering column for the center seat; rear-facing rows get a rear-facing center occupant.
• Per-row Symmetric toggle (on by default). Turn it off for a single occupant placed anywhere across the cabin by a signed lateral offset (plus or minus 700 mm). Handy for jump seats and asymmetric cab layouts.
• With symmetry off, the door trims hold a fixed, symmetric cabin about the centerline, and the Shoulder Room readout always reports the true door-to-door width, so the numbers stay honest even with an off-center occupant.
• Steering wheel and column follow the driver across the centerline in asymmetric layouts.

Posture and controls

• Unlocking the driver Back Angle (A40) now reclines the whole manikin, torso, neck, and J1052 head form, not just the seat back. The eyellipse itself stays package-fixed per J941, since it's a statistical reference point, not something that reclines with the driver.
• Two new driver-station inputs: Seat Track Travel (TL23) and Wheel to PRP (L6), the latter with a lock/derive toggle.
• The Eyellipse visibility toggle actually works now (it was present but inactive before).

Removed and deprecated

• Clutch Pedal input dropped. The J941 clutch term is omitted going forward and treated as zero.
• Vehicle Class (Class A/B tilt) is deprecated. J941 (2002) uses one 12 degree tilt for everyone. The setting is still there for old files to load cleanly, but it no longer does anything.

v1.7.1: one bug fix

• Remove Row could leave a 3-across center occupant behind. If Center Occupant was turned on for a row, removing that row used to leave the center passenger and its marker in the scene. The only fix was turning the row back on, switching Center Occupant off, then removing the row again. Remove Row now clears the center occupant correctly the first time.

Compatibility

• Saved .blend files from v1.6.2 open normally. The eyellipse will reposition itself to match the new J941 math the first time the file updates, and files using the old 133 mm short-track default will draw the short-track eyellipse axis until you set Seat Track Travel to your actual value.
• The passenger eyellipse isn't part of this release. A documented passenger placement is planned.

v1.6.0 — Curb Industries, INC.

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A procedural vehicle-packaging tool for Blender, built around the SAE J1100

Motor Vehicle Dimensions standard. Designed for concept car designers,

transportation design students, and automotive packaging enthusiasts who want

to explore interior layout, seating geometry, and occupant accommodation

directly inside their 3D environment.

NOTE: This tool generates reference geometry based on SAE standards and

published dimensional relationships. All outputs are approximations intended

for advanced concept development and early-stage packaging studies. Validate

dimensions and spatial relationships with a qualified studio engineer before

using outputs to inform design decisions. H-Point: Package Builder is not a

substitute for production-level packaging tools or regulatory compliance

software.

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WHAT IT DOES

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H-Point: Package Builder generates a complete occupant packaging study inside

Blender from a small set of high-level inputs — seat height, torso angle,

pedal position, and vehicle type. From those inputs it procedurally builds:

  - SAE J826 kinematic manikins (driver and passenger) with correct skeletal

    geometry driven by seat height

  - H-Point / SgRP markers per seating station

  - Seat contour reference profiles based on the J826 H-Point Machine template

  - SAE J941 eyellipse and J1052 head contour reference volumes

  - Steering wheel and column geometry

  - Bounding box and vehicle envelope reference planes

  - Tire and wheel assemblies from standard ISO/SAE tire codes

  - Knee blocker packaging clearance indicator (SAE L62)

  - Ground plane and wheelbase reference geometry

All geometry updates live as you adjust parameters — move the seat height

slider and every dependent element (manikin posture, eyellipse, headroom,

knee blocker clearance) recalculates.

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REQUIREMENTS

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  - Blender 4.2 or later (Extension format required)

  - No external Python dependencies

FIRST-LOAD NOTE

  If your Blender preferences have "Auto Run Python Scripts" disabled

  (Edit > Preferences > Save & Load), you'll see a one-time security banner

  the first time you open a .blend file containing an H-Point package. Click

  "Allow Execution" once; the package's scripted drivers will then evaluate

  normally for the rest of the session. This is Blender's standard security

  flow for any addon that ships scripted drivers.

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INSTALLATION

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  1. Download the addon zip from your purchase confirmation.

  2. Open Blender and go to Edit > Preferences > Get Extensions

  3. Click the dropdown arrow (top right) > Install from Disk

  4. Select the downloaded zip

  5. Enable the extension if not already active

The H-Point tab will appear in the 3D Viewport Sidebar (press N to open).

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QUICK START

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  1. Open the H-Point tab in the 3D Viewport Sidebar

  2. Click Create Package to generate a default single-row layout

  3. Adjust seat height, torso angle, pedal position, and other parameters —

     geometry updates automatically

  4. Use Add Row to add second or third row seating

  5. Use the Interior, Exterior, Seating, and Tire panels to refine individual

     elements

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FEATURES

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OCCUPANT PACKAGING

  - SAE J826 kinematic driver and passenger manikins (50th percentile)

  - Seat height range with full limb kinematics driven by seat height (SH)

  - Independent torso angle (TAD / A40) control with lock/unlock

  - Heel point and accelerator pedal reference geometry

SEAT REFERENCE PROFILE

  - Seatback and cushion reference lines offset from H-point per J826 template

  - Smooth Bezier radius at the seatback/cushion junction

  - Adjustable surface offset, cushion angle (L27), seatback height, cushion

    length, and corner radius

VISION & HEADROOM

  - SAE J941 eyellipse (95th percentile binocular) — driver and passenger

  - SAE J1052 head contour reference

  - Headroom clearance reference geometry

STEERING

  - Steering wheel diameter and tilt angle

  - Column reach and offset controls

KNEE BLOCKER CLEARANCE

  - SAE L62 packaging clearance indicator, parallel to shin geometry

  - Adjustable clearance value with show/hide toggle

TIRE & WHEEL

  - Full tire and wheel assembly from ISO/SAE tire code string

  - Front and rear independent configuration

  - Wheel offset, diameter, and section width controls

BOUNDING BOX & REFERENCE GEOMETRY

  - Vehicle envelope bounding box

  - Ground plane, wheelbase line, and section reference planes

  - Per-row collection organisation in the Blender outliner

APPEARANCE

  - Per-row colour assignment

  - All reference geometry organised into named collections

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SAE REFERENCES

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  SAE J1100   Motor Vehicle Dimensions

  SAE J826    Devices for Use in Defining and Measuring Vehicle Seating

              Accommodation

  SAE J826/2  H-Point Machine — CAD Version

  SAE J941    Motor Vehicle Drivers' Eye Locations

  SAE J1052   Motor Vehicle Driver and Passenger Head Position

  SAE L62     Knee Clearance to Interior Components

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VERSION HISTORY

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See CHANGELOG.md at the project root for the full history, including the

pre-1.0 v7.x development line.

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SUPPORT & CONSULTATION

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TheCurbShop.com — tools, books, and resources for automotive designers

For professional consultation on vehicle packaging, occupant accommodation

studies, or studio-level dimensional validation, contact Curb Industries, INC.

  Website:  https://www.TheCurbShop.com

  Email:    [email protected]

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LICENSE

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H-Point: Package Builder is licensed under the GNU General Public License

v2 or later (GPL-2.0-or-later). See LICENSE at the project root for the full

text and TRADEMARKS.md for trademark terms.

H-Point: The Fundamentals of Car Design & Packaging (2nd Edition)

Available at TheCurbShop.com

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