SURFACE
J2732 JUN2008
VEHICLE STANDARD
Issued
2008-06
Motor Vehicle Seat Dimensions
RATIONALE The Motor Vehicle Dimensions Recommended Practice (SAE J1100) has a limited number of seating measurements related to automotive interior space. This document provides additional and more comprehensive dimensional measurements specifically for the design, evaluation and benchmarking of vehicle seats. Coordinate references are established along the cushion and seat back to better define seat characteristics. These dimensions are based primarily on the use of the SAE J4002 HPM-II that provides divot points, support points, a measure of lumbar support prominence, and many seat measures that can be taken independent of the seating package. Many of the definitions and measurements can be made with the SAE J826 H-point machine (HPM); however, the measured values may not be identical to values taken using HPM-II. TABLE OF CONTENTS INTRODUCTION................ INTRODUCTION .................................. .................. .................. .................. .................. .................. ..................... .................. .................. .. 2 1.
SCOPE. SCOPE... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... .. 2
2. 2.1 2.1.1 2.1.1
NORM NORMAT ATIV IVE E REFE REFERE RENC NCES... ES..... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .. 3 Applic Applicabl able e Public Publicati ations.... ons...... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ... 3 SAE SAE Public Publicati ations. ons.... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ..... .... .... ..... ...... ...... ...... ...... ...... ...... ...... ..... .. 3
3.
DEFI DEFINI NITI TION ONS S .... ...... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... 4
4. 4.1 4.2 4.3
CODE CODE EXPL EXPLAN ANAT ATIO ION N .... ...... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... 7 Prefi Prefix x Codes.. Codes.... ..... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ..... .... ..... ...... ...... ...... ...... ...... ...... ...... ...... ..... .. 7 Seat Seat Positi Position on Codes Codes ...... ......... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ... 8 Cross Cross Sectio Sectional nal Code Code ..... ........ ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... .. 8
5.
SEAT SEAT DIME DIMENS NSIO IONS.. NS.... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... .... 9
6. 6.1
NOTES... NOTES...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ..... .... ..... ...... ..... ..... ...... ...... ...... ...... ...... ..... 18 Margin Marginal al Indici Indicia a ..... ........ ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... ..... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ...... ..... 18
APPENDIX A
(INFORMATIVE) (INFORMATIVE) RECOMMENDED RECOMMENDED SEAT CROSS CROSS SECTIONS................. SECTIONS........................... ................... ................... ................... ................. ........ 19
BIBLIOGRAPHY BIBLIOGRAPHY .................. ........................... .................. .................. ................... ................... .................. .................. .................. .................. .................. ................. ................. ................... ................... .................. .................. ......... 22
_________________________________________ _____________________ _________________________________________ __________________________________________ _________________________________________ _________________________________________ ___________________________________ ______________ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright © 2008 SAE International All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER:
Tel: Tel:
877-606-7323 (inside USA and Canada) 724-776-4970 (outside USA)
SAE
J2732 Issued JUN2008
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INTRODUCTION The tools and procedures for determining motor vehicle seat dimensions used in this document are based on the SAE J4002 H-Point Machine (HPM-II). Many of the definitions and measurements can be made with the SAE J826 H-point machine (HPM), however the measured values may not be identical to values taken using HPM-II. Since the SAE J826 HPM does not have support or divot points, dimensions based on these points are difficult to measure in the field, but can readily be measured in CAD if desired. The LSP measure is not available with the SAE J826 HPM. Users shall document and maintain a record noting whenever the SAE J826 HPM is used in making the measurements cited in this document. H-point devices are used (1) during vehicle design and development to establish interior reference points and dimensions for occupant packaging, (2) to validate (audit) the location of these key reference points and dimensions on physical properties, and (3) to measure competitive vehicles for benchmarking. The procedures employed for each usage vary somewhat. SAE J4002 describes the use of the HPM-II in auditing vehicle seats and other interior compartment dimensions. SAE J4003 describes the use of the HPM-II in benchmarking. Audits are conducted by regulatory agencies and OEMs to assess how closely the vehicle is manufactured to its design intent. Although serving different purposes, auditing and benchmarking procedures are very similar. The most significant difference between them is that audits use actual design intent values to set up the vehicle and position the seat, whereas benchmarking is used to discover the design intent values for competitor vehicles. 1. SCOPE This document provides dimension definitions that facilitate geometric quantification and evaluation of seats. Dimensions described in this document have been designed to be measured in a CAD environment; however, many dimensions require the HPM position and attitude. This can be obtained by physically establishing H-point using benchmark or auditing procedures OR by measuring the HPD within a CAD or modelling system. Refer to the appropriate document for these procedures. These dimensions are package independent in that they do not require use of the HPM-II supplemental thigh/leg/shoe. Three types of seat geometry reference points and measurements have been developed: •
•
•
Simple reference points and measurements not related to H-point. H-point dependent reference points and measurements that utilize the seat characterization capabilities of the HPM to quantify seat measurements. Cross sectional seat trim outlines.
For convenience and simplicity, many terms associated with H-point devices use human body parts in their name. However, they should not be construed as measures that indicate interaction with any or all occupants concerning accommodation, human capabilities, or comfort. H-point devices do not represent the size or posture of any category of occupant.
SAE 2.
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NORMATIVE REFERENCES
2.1
Applicable Publications
This document contains provisions which reference the following documents. The latest edition of the reference applies. 2.1.1
SAE Publications
Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. SAE J182
Motor Vehicle Fiducial Marks and Three-dimensional Reference System
SAE J826
Devices for Use in Defining and Measuring Vehicle Seating Accommodation
SAE J1100
Motor Vehicle Dimensions
SAE J4002
H-Point Machine (HPM-II) Specifications and Procedure for H-Point Determination—Auditing Vehicle Seats
SAE J4003
H-Point Machine (HPM-II)—Procedure for H-Point Determination—Benchmarking Vehicle Seats
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DEFINITIONS
For the purposes of this document, the following definitions apply. TABLE 1 - SEAT DEFINITIONS Term
Definition
Figure
A-Surface
Surface of a seat, or any of its components, that is closest to the occupant. For example, the A-surface of the foam pad is the surface the occupant sits on.
3
B-Surface
Surface of a seat, or any of its components, that is furthest from the occupant (opposite the A-surface). For example, the B-surface of the foam pad is the surface in contact with the frame.
3
Bench Seat
Seat structure designed to hold multiple occupants.
Biteline (seat bight)
Area close to and including the intersection of the surface of the vehicle seat cushion and seat back.
2
Bolster
Raised contour at lateral edges of the seat cushion and seat back.
2
Bucket Seat
Seat structure designed to hold a single occupant usually contoured to hold the occupant.
Centerline of Occupant (C/LO)
Lateral (Y) centerline of an occupant in a given designated seating position. See SAE J1100. C/LO is repeated in this section for convenience. In the case of a CL trench or decorative raised regions, a lateral offset can be used to approximate the centerline.
2
Cross Car
Lateral direction across vehicle (+Y, -Y).
1
Deflection (HPM)
Distance between the free unloaded seat trim contour prior to HPM installation and the HPM surface, when loaded in the seat.
4
Head Restraint
Protective device that limits the rearward displacement of a seated occupant’s head relative to the occupant’s torso.
2
Insert
Primary seating region between the bolsters on the seat cushion and seat back, usually defined with a seam or line in the trim A-Surface.
2
Lumbar Region
Area of the seat back that provides support for an occupant’s lower back – can be adjustable or static.
N/A
Protruded (Extended)
Refers to an adjustable mechanism when it is in its maximal or projected state.
N/A
Retracted
Refers to an adjustable mechanism when it is in its minimal or withdrawn state.
N/A
Seat Adjuster
Refers to mechanisms used to alter position, shape, or support characteristics of the seat.
N/A
Seat Back
Part of the seat that supports the occupant’s back.
2
Seat Cushion
Part of the seat that supports the occupant’s buttocks and thighs.
2
Split Bench Seat
Seat structure designed to hold multiple occupants that may be split for independent adjustment of two or more occupant positions.
N/A
Tie-down
Depression or line in the A-surface of the trim cover created by the attachment of trim to seat components.
N/A
Trench
Recess in the foam pad used to accommodate or attach seams in the trim cover.
Trim Cover
Material or attachment used to cover a seat.
Trim Prominence
Most prominent point on the undeflected profile of the seat trim defined by the tangent point of a line parallel to a reference line such as the Cushion or Torso (Back) Line.
N/A
N/A
2 N/A 3
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FIGURE 1 - THREE DIMENSIONAL REFERENCE SYSTEM, SEE SAE J1100
FIGURE 2 - GENERAL SEAT DEFINITIONS
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FIGURE 3 - GENERAL SEAT DEFINITIONS (CROSS SECTION) TABLE 2 - HPM SPECIFIC DEFINITIONS Term
Definition
Figure
Cushion Line
Line from the H-point through the C1 divot point. See SAE J4002.
4
D-point
Located on the bottom of the cushion pan, at the lateral centerline, 25.5 mm (15 degrees) rearward of the H-point (when cushion angle equals 0). This point is identified by a divot point on the surface of the cushion pan. See SAE J1100.
4
Divot Points
Fourteen divot points are provided on the HPM. See SAE J4002.
Exit Point
Point where the undeflected trim separates from the manikin’s surface. Exit Points are determined using CAD. Lateral Exit Points are referenced to the HPM centerline. The measurement process assumes that HPM centerline is at the centerline of occupant (C/LO).
4
H-point
Point at the pivot center of the back pan and cushion pan assemblies, located on the lateral centerline of the H-point device (HPM or HPD). See SAE J4002. NOTE 1: When an H-point device is properly positioned within a vehicle – either in CAD or in an actual physical property – the location of the H-point relative to the vehicle is used as a vehicle reference point. If the seat is moved, the location of the H-point within the vehicle is changed. Therefore, adjustable seats will have more than one H-point location, while fixed seats will have only one H-point location. NOTE 2: H-points are often referred to as hip points or hip pivot points. However, they do not accurately represent the location of the human hip joint.
4
Support Points
There are nine support points: 5 located on the outer surface of the cushion pan and 4 on the back pan assembly. See SAE J4002.
N/A
Torso (Back) Line
Line from the H-point through the sliding thoracic pivot (B1 divot point). See SAE J4002.
4
N/A
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FIGURE 4 - HPM SPECIFIC DEFINITIONS 4.
CODE EXPLANATION
Each dimension is assigned a code, which consists of an alpha prefix and a number. The letters denote the direction or type of measurement (e.g. W - Width, A - Angle). See Table 3. Numeric codes relate to the type of vehicle dimension. Seat specific dimensions range between 1000–1999 (e.g. W1020). See Table 4. Users shall record pertinent design, setup, and measurement information, including settings for user adjustable features (e.g. lumbar support or thigh extender), CAD vs. field measurement, and the HPM (SAE J4002 / SAE J826) used to set the reference position and attitude. 4.1
Prefix Codes TABLE 3 - PREFIXES Letter
Meaning
W
Widths associated with seats (cross car distance).
L
Lengths associated with seats.
H
Heights associated with seats.
A
Angles associated with seats.
R
Radii associated with seats.
TABLE 4 - NUMERIC SCHEME Number Range
Type of Dimension
1–99
Interior (General Seat Dimensions).
1000–1199
Seat Cushion Lateral Dimensions.
1200–1399
Seat Cushion Centerline Dimensions.
1400–1599
Seat Back Lateral Dimensions.
1600–1799
Seat Back Centerline Dimensions.
1800–1999
Seat Head Restraint Dimensions.
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Seat Position Codes
These dimensions can be applied to several designated seating positions. In order to indicate a specific seat position, the basic alphanumeric code remains the same, but an additional alphanumeric code is added (e.g., H30-1-L, H30- 2-R, H30-3-C). The number indicates the designated seating row. See Table 5. The letter indicates the seating position in that particular row. See Table 6 (e.g. W1015-1-L). TABLE 5 - SEATING ROW Row Number
Designated Seating Row
-1
Front Row Measurement.
-2
Second Row Measurement.
-3
Third Row Measurement.
-4
Fourth Row Measurement.
-5
Fifth Row Measurement.
TABLE 6 - SEATING POSITION (SUFFIX)
4.3
Letter
Designated Seating Position
-L
Measurement taken for the left, outboard designated seating position. (-Y in vehicle coordinates)
-R
Measurement taken for the right, outboard designated seating position. (+Y in vehicle coordinates)
-C
Measurement taken for the center designated seating position.
-B
Measurement taken for an entire bench seat (such as overall width).
Cross Sectional Code
Selected dimensions are measured at a given distance from H-point along or normal to a given reference line and are denoted with _X (where X equals the distance in mm from H-point ) following the alphanumeric prefix (e.g. W1020_100). See Figure 5 and Appendix A.
FIGURE 5 - CROSS SECTIONS AND CENTERLINE SECTIONS
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SEAT DIMENSIONS
The dimension definitions that follow are shown with no suffix codes to indicate seat row or position. In practice the proper suffix codes should be added to identify seat aspects. Note also that certain seat and package dimensions are repeated in this Section for convenience. TABLE 7 - GENERAL SEAT DIMENSIONS Code
Dimension
Definition
Figure
A27
Cushion Angle
Angle of the Cushion Line from the horizontal with the HPM loaded in the seat with the seat at design attitude. See SAE J4002.
6
A42
Hip Angle
Included angle between the Cushion Line and Torso (Back) Line with the seat at design attitude. See SAE J1100.
6
A40
Torso Angle
Angle measured between a vertical line through the H-point and the Torso (Back) Line. See SAE J1100.
6
Lumbar Support Prominence
LSP is a measure of the attitude (posture) of the H-point device. It is defined as 57 mm minus the distance from the lumbar-pelvic pivot point to the Torso (Back) line, measured normal to the Torso (Back) line. When LSP = 0, the posture is referred to as neutral. The suffix following L81 identifies the designated seating position. See SAE J1100.
6
L81
FIGURE 6 - BASIC HPM DIMENSIONS
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TABLE 8 - SEAT CUSHION LATERAL CROSS SECTION DIMENSIONS Code
Dimension
Definition
Figure
W1000_X
Seat Cushion Width
Width across the seat cushion soft trim surface within a cross sectional plane normal (90 deg) to the Cushion Line.
7a
W1020_X
Seat Cushion Bolster Width
Width between the highest points on the bolsters within a cross sectional plane normal (90 deg) to the Cushion Line.
7a
W1040_X
Seat Cushion Insert Width
Width of the insert between the bolsters within a cross sectional plane normal (90 deg) to the Cushion Line. In certain cases this measure is not definable.
7a
H1060_X
Seat Cushion Bolster Height
Height of the bolsters above the centerline (C/L) insert within a cross sectional plane normal (90 deg) to the Cushion Line. In certain cases this measure is not definable.
7a
R1080_X
Seat Cushion Bolster Radius
Radius defined by the arc of the highest point of the outboard bolster, the highest point of the inboard bolster, and the surface of the centerline (C/L) insert within a cross sectional plane normal (90 deg) to the Cushion Line. In certain cases this measure is not definable.
7c
W1100_X
Seat Cushion Lateral Exit Point
Distance from the seat centerline to the lateral exit points within a cross sectional plane normal (90deg) to the Cushion Line. If the seat is not symmetrical use only the outboard side. In the case of a trench use furthest lateral exit pt.
7b
H1120_X
Seat Cushion Trim Deflection
Distance from the manikin surface to the undeflected seat cushion surface measured within a cross sectional plane normal (90 deg) to the Cushion Line.
7b
H1140_X
Seat Cushion Bolster Asymmetry
Difference in outboard bolster height and inboard bolster height within a cross sectional plane normal (90deg) to the Cushion Line. Center seats should use the same convention as the left outboard seat position. Value will be negative if inboard bolster is higher than outboard bolster.
7c
FIGURE 7A - SEAT CUSHION LATERAL CROSS SECTION DIMENSIONS
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FIGURE 7B - HPM SPECIFIC SEAT CUSHION LATERAL CROSS SECTION DIMENSIONS
FIGURE 7C - SEAT CUSHION LATERAL CROSS SECTION BOLSTER ASYMMETRY AND RADIAL DIMENSIONS
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TABLE 9 - SEAT CUSHION CENTERLINE SECTION DIMENSIONS Code
Dimension
Definition
Figure
H1200_X
Seat Cushion Trim Prominence to Cushion Line
Distance measured normal (90 deg) to the Cushion Line from the Seat Cushion Trim Prominence to the Cushion Line.
8a
L1220_X
Seat Cushion Trim Prominence to H-point
Distance measured parallel to the Cushion Line from H-point to the Seat Cushion Trim Prominence.
8a
L1240_X
Cushion Biteline Exit Point
Distance measured parallel to the Cushion Line from H-point rearward to a line normal to the Cushion Line at the exit point.
8b
L1260_X
Cushion Thigh Exit Point
Distance measured parallel to the Cushion Line from H-point forward to a line normal to the Cushion line at the exit point. Usually offset from centerline of occupant (C/LO) by 100mm.
8b
L1280_X
Seat Cushion Length to H-point
Distance measured parallel to the Cushion Line from H-point to a line normal (90 deg) to the Cushion Line tangent to the front of the cushion at centerline of occupant (C/LO).
8a
L1300_X
Seat Cushion Tie-down Location
Distance measured parallel to the Cushion Line from H-point to a line normal to the Cushion Line at the closest cross car tie down on the A-Surface of the seat. This measurement is positive (forward of H-point) or negative (rearward of H-point).
8a
FIGURE 8A - SEAT CUSHION CENTERLINE SECTION
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FIGURE 8B - HPM SPECIFIC SEAT CUSHION CENTERLINE SECTION
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TABLE 10 - SEAT BACK LATERAL CROSS SECTION DIMENSIONS Code
Dimension
Definition
Figure
W1400_X
Seat Back Width
Width across the soft trim surface within a cross sectional plane normal (90 deg) to the Torso (Back) Line.
9a
W1420_X
Seat Back Bolster Width
Width between the most forward points of the bolsters within a cross sectional plane normal (90 deg) to the to the Torso (Back) Line.
9a
W1440_X
Seat Back Insert Width
Width of the insert between the bolsters within a cross sectional plane normal (90 deg) to the to the Torso (Back) Line. In certain cases this measure is not definable.
9a
H1460_X
Seat Back Bolster Height
Distance of the bolsters forward of the insert at the centerline (C/L) within a cross sectional plane normal (90 deg) to the Torso (Back) Line. In certain cases this measure is not definable.
9a
R1480_X
Seat Back Bolster Radius
Radius defined by the arc of the highest point of the outboard bolster, the highest point of the inboard bolster, and the surface of the centerline (C/L) insert within a cross sectional plane normal (90deg) to the Torso (Back) Line. In certain cases this measure is not definable.
9c
W1500_X
Seat Back Lateral Exit Points
Distance from the seat centerline to the lateral exit points within a cross sectional plane normal (90 deg) to the Torso (Back) Line. If the seat is not symmetrical, use only the outboard side. In the case of a trench use furthest lateral exit pt.
9b
H1520_X
Seat Back Trim Deflection
Distance from the manikin surface to the undeflected trim, measured within a cross sectional plane normal (90 deg) to the Torso (Back) Line.
9b
Difference in bolster depth on outboard side to inboard within a cross sectional plane normal (90 deg) to the Torso (back)line. Center seats should use the same convention as the left outboard seat position. Value will be negative if inboard bolster is bigger than outboard bolster
9c
H1540_X
Seat Back Bolster Asymmetry
FIGURE 9A - SEAT BACK LATERAL CROSS SECTION DIMENSIONS
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FIGURE 9B - HPM SPECIFIC SEAT BACK LATERAL CROSS SECTION DIMENSIONS
FIGURE 9C - SEAT BACK LATERAL CROSS SECTION BOLSTER ASYMMETRY AND RADIAL DIMENSIONS
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TABLE 11 - SEAT BACK CENTERLINE SECTION DIMENSIONS Code
Dimension
Definition
Figure
L1600_X
Seat Back Trim Prominence to Torso (Back) Line
Distance from the seat Back Trim Prominence to the Torso (Back) Line measured normal (90 deg) to the Torso (Back) Line along centerline of occupant C/LO.
10a
H1620_X
Seat Back Trim Prominence to H-point
Distance from the Seat Back Trim Prominence to the H-point measured parallel to the Torso (Back) Line along centerline of occupant (C/LO).
10a
H1640_X
Back Biteline Exit Point
Distance from the H-point parallel to the Torso (Back) Line to a line normal to the Torso (Back) Line at the exit point. This measure can be either positive (above Hpoint) or negative (below H-point).
10b
H1660_X
Upper Back Exit Point
Distance from the H-point parallel to the Torso (Back) Line to a line normal to the Torso (Back) Line at the exit point.
10b
H1680_X
Seat Back Height from H-point without Head Restraint
Distance from the H-point along the Torso (Back) Line to the intersection at a line normal (90 deg) to the Torso (Back) Line, tangent to the top of the seat back at centerline of occupant (C/LO). Head restraint is excluded. This measurement does not apply for integrated head restraints.
10a
H1700_X
Seat Back Tie-Down Location
Distance from H-point parallel to the Torso (Back) Line to a line normal to the Torso (Back) Line at the closest cross car trench in the seat back. This measurement can be positive (above H-point) or negative (below H-point).
10a
FIGURE 10A - SEAT BACK CENTERLINE SECTION DIMENSIONS
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FIGURE 10B - HPM SPECIFIC SEAT BACK CENTERLINE SECTION DIMENSIONS
TABLE 12 - HEAD RESTRAINT DIMENSIONS Code
Dimension
Definition
Figure
H1800_X
Seat Back Height from H-point with Head Restraint
Distance measured parallel to the Torso (Back) Line from the H-point to the intersection of a line normal (90 deg) to the Torso (Back) Line and tangent to the top of the headrest. If the head restraint is adjustable it is placed in the full down position. This dimension is similar to ECE Head Restraint Height
11
W1820
Head Restraint Width
Width across trimmed surfaces of the head restraint at widest points.
11
H1840_X
Head Restraint Height
Distance measured parallel to the Torso (Back) Line from a line normal (90 deg) to the Torso (Back) Line tangent to the bottom of the head restraint to a line normal to the Torso (Back) Line tangent to the top of the head restraint.
11
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FIGURE 11 - HEAD RESTRAINT DIMENSIONS 6. NOTES 6.1
Marginal Indicia
A change bar (I) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only.
PREPARED BY THE SAE HUMAN ACCOMMODATION AND DESIGN DEVICES COMMITTEE
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APPENDIX A - (INFORMATIVE) RECOMMENDED SEAT CROSS SECTIONS Dimensions described in this document can be measured at distances from H-point along a given reference line. This distance is denoted by _X where X is the offset from H-point (see Figures below). This section describes a minimum set of recommended cross sections intended for seat comparisons and evaluations. Although used for reference these HPM sections and locations do not represent the size or posture of any category of occupant. Additionally, the H-point does not represent the location of the human hip joint. TABLE A1 - SEAT CUSHION DIMENSIONS Code _0 _125 _250 _0 _110
Section Lateral Cross Section Lateral Cross Section Lateral Cross Section Centerline Cross Section Centerline Cross Section
Definition 0 mm forward of H-point (plane normal to cushion line through CP1). 125 mm forward of H-point (plane normal to cushion line through CP2). 250 mm forward of H-point (plane normal to cushion line through CP3). 0 mm lateral of H-point (plane parallel to the cushion and torso (back) line through H-point). ±110 mm on either side of H-point (dependent on outboard or inboard requirement).
Figure A1 A1 A1, A3 A2 A2
TABLE A2 - SEAT BACK DIMENSIONS _35 _175 _350 _0 _110
Lateral Cross Section Lateral Cross Section Lateral Cross Section Centerline Cross Section Centerline Cross Section
35 mm above the H-point (plane normal to torso (back) line through BP1). 175 mm above the H-point (plane normal to torso (back) line through BP2). 350 mm above the H-point (plane normal to torso (back) line through BP3). 0 mm lateral of H-point (plane parallel to the cushion and torso (back) line through H-point). ±110 mm on either side of H-point (dependent on outboard or inboard requirement).
A1 A1 A1, A4 A2 A2
SAE
J2732 Issued JUN2008
FIGURE A1 - RECOMMENDED LATERAL CROSS SECTIONS REFERENCED FROM H-POINT
FIGURE A2 - RECOMMENDED CENTERLINE SECTIONS REFERENCED FROM H-POINT (SHOWS POSITIVE AND NEGATIVE OFFSET)
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SAE
J2732 Issued JUN2008
FIGURE A3 - EXAMPLE HPM SEAT CUSHION CROSS SECTION THROUGH THIGH (250 mm FORWARD OF H-POINT)
FIGURE A4 - EXAMPLE HPM SEAT BACK CROSS SECTION THROUGH SHOULDERS (350 mm ABOVE H-POINT)
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SAE
J2732 Issued JUN2008
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BIBLIOGRAPHY ASPECT/SAE Seat Dimensions Task Group, “Proposed Seat Dimension Definitions for SAE J1100 Derived from Aspect (HPMII),” Final Report, November 30, 1999