1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to 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 theref
2、rom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2012 SAE International All rights reserved. No part of this pub
3、lication 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: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970
4、(outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/J2896_201201SURFACEVEHICLERECOMMENDEDPRACTICEJ2896 JAN2012 Issued 2012-01Motor Vehic
5、le Seat Comfort Performance Measures RATIONALEThis document provides technology, terminology, and procedural updates to performance measurements related to occupant support, penetration into the seat, and mechanical aspects of comfort in the seat. These measurements are used in the automotive seatin
6、g industry and were initially described in the SAE Seating Manual (SAE J782). Measurements in this document supersede any similar measurements given in SAE J782. TABLE OF CONTENTS 1. SCOPE 32. REFERENCES 32.1 Applicable Documents 32.2 SAE Publications . 32.3 Other Publications . 33. DEFINITIONS . 44
7、. TEST SEAT . 44.1 Seat Complete 44.2 Conditioning 44.3 Seat Setup 44.4 Adjustable Features 55. TEST METHODS 55.1 Overall Load Deflection . 55.2 Hardness Profile 115.3 Impact Absorption Test . 165.4 Vibration and Transmissibility . 186. NOTES 216.1 Marginal Indicia . 21SAE J2896 Issued JAN2012 Page
8、2 of 35 APPENDIX A (INFORMATIVE) STATIC BODY PRESSURE DISTRIBUTION . 22APPENDIX B (INFORMATIVE) APPLICATION GUIDANCE . 31APPENDIX C (INFORMATIVE) RECOMMENDED SEAT CROSS SECTIONS . 34FIGURE 1 EXAMPLE STATIC LOAD DEFLECTION TEST EQUIPMENT 5FIGURE 2A SEAT BACK PRESSING PLATES . 7FIGURE 2B SEAT CUSHION
9、PRESSING PLATES . 7FIGURE 3 SEAT CUSHION AND SEAT BACK SETUP 7FIGURE 4 LOAD DEFLECTION CURVE . 8FIGURE 5 AREA UNDER LOADING AND UNLOADING CURVES 9FIGURE 6 HYSTERESIS LOSS AT GIVEN LOAD 9FIGURE 7 STATIC SPRING CONSTANT (TANGENT METHOD) 10FIGURE 8A STATIC SPRING CONSTANT (SLOPE AND RELATIVE DEFLECTION
10、 METHODS) 10FIGURE 8B RELATIVE DEFLECTION COMPARISON METHOD 11FIGURE 9 EXAMPLE HARDNESS PROFILE TEST EQUIPMENT . 11FIGURE 10 RECOMMENDED COLUMN TYPE PRESSING PLATES . 12FIGURE 11 SEAT CUSHION AND SEAT BACK SETUP 13FIGURE 12 LOCAL POINT ARRAY EXAMPLE . 13FIGURE 13 LOCAL LOAD-DEFLECTION GRAPH . 14FIGU
11、RE 14 2-D HARDNESS PROFILE . 15FIGURE 15 PENETRATION CONTOUR . 15FIGURE 16 3-D LOADED CONTOUR . 15FIGURE 20 EXAMPLE IMPACT ABSORPTION TEST EQUIPMENT . 16FIGURE 20 IMPACT TEST SETUP . 17FIGURE 21 IMPACT DAMPING GRAPH . 18FIGURE 17 EXAMPLE VIBRATION TRANSMISSIBILITY TEST EQUIPMENT 19FIGURE 18 SETUP 20
12、FIGURE 19 TRANSMISSIBILITY PLOT . 21FIGURE A1 EXAMPLE PRESSURE MAT TEST EQUIPMENT . 22FIGURE A2 BASIC BPD PROCESS 24FIGURE A3 EXAMPLE OUTPUT . 26FIGURE A4 EXAMPLE PRESSURE SENSORS AND ARRAY . 26FIGURE A5 AVERAGE SCAN CALCULATIONS . 27FIGURE A6 EXAMPLE APPLICATION OF A COORDINATE REFERENCE 28FIGURE A
13、7 EXAMPLE MAT REGIONS DEFINED FROM H-POINT REFERENCE . 29FIGURE A8 REGIONAL GRAPHS . 29FIGURE A9 EXAMPLE LUMBAR DIFFERENCE SCAN 30FIGURE C1 RECOMMENDED LATERAL CROSS SECTIONS REFERENCED FROM H-POINT . 35FIGURE C2 RECOMMENDED CENTERLINE SECTIONS REFERENCED FROM H-POINT (SHOWS POSITIVE AND NEGATIVE OF
14、FSET) . 35TABLE 1 DEFINITIONS . 4TABLE C1 SEAT CUSHION SECTIONS 34TABLE C2 SEAT BACK SECTIONS. 34SAE J2896 Issued JAN2012 Page 3 of 35 INTRODUCTIONThis document provides recommended test methods for evaluating performance characteristics of motor vehicle seating related to occupant support, penetrat
15、ion, and comfort. It provides a means of comparing and assessing comfort-related performance of complete, prototype, or competitive benchmark vehicle seat systems.Additionally, this document provides a framework for documenting relevant parameters of these tests in order to aid in interpretation of
16、diverse data sets and address issues of measurement variation. In general, measurement variation in these tests arises primarily from manufacturing variability, seat set-up differences (including determination of the SgRP reference and orientation), and finally user variations in the actual test pro
17、cedures. This document does not make recommendations for tolerance. The tools and procedures for determining seat coordinate positions used in this document are based on the SAE J4002 H-Point Machine (HPM-II). Many of the measurements can be made with the SAE J826 H-point machine (HPM), however the
18、measured values may not be identical to values taken using HPM-II. Users shall document and maintain a record noting whenever the SAE J826 HPM is used in making the measurements cited in this document. For convenience and simplicity, many terms associated with H-point devices use human body parts in
19、 their name. However, they should not be construed as measures that indicate interaction with any or all occupants concerning accommodation, human capabilities, or comfort. 1. SCOPE These test procedures apply to complete seat systems (production seats or prototypes built at the intended manufacturi
20、ng quality); however, the procedures can be modified for subsystem or component level testing. 2. REFERENCES 2.1 Applicable Documents The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall ap
21、ply. 2.2 SAE Publications Available from SAE International, 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 J1100 Motor Vehicle Dimensions SAE J2732 Motor Vehicle Seat Dimensions SAE J182 Motor Vehicle Fiduci
22、al Marks and Three-dimensional Reference System SAE J4002 H-Point Machine (HPM-II) - Specifications and Procedure for H-Point Determination - Auditing Vehicle SeatsSAE J4003 H-Point Machine (HPM-II) - Procedure for H-Point Determination - Benchmarking Vehicle Seats SAE J826 Devices for Use in Defini
23、ng and Measuring Vehicle Seating Accommodation 2.3 Other Publications JASO B407 (1987) Test Code of Seating Comfort for Automobile Seats SAE J2896 Issued JAN2012 Page 4 of 35 3. DEFINITIONS For the purposes of this document, the following definitions apply. TABLE 1 - DEFINITIONS Term Definition Bite
24、line (seat bight) Area close to and including the intersection of the surface of the vehicle seat cushion and seat back.See SAE J2732. Centerline of Occupant (C/LO) Lateral (Y) centerline of an occupant in a given designated seating position. See SAE J1100. Cross Car Lateral direction across vehicle
25、 (+Y, -Y). See SAE J182 H-pointPoint 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 and J1100. NOTE 1When an H-point device is properly positioned within a vehicle either in CAD or in an actual physi
26、cal 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 l
27、ocation. 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. Lateral Section (Seat) Section perpendicular to the Centerline of Occupant plane. NOTE: This section is usually the same as Cross Car. Long
28、itudinal Section (Seat) Fore aft Section parallel to the Centerline of Occupant plane. Seat Surface Reference Load The Minimum Load used to define initial contact with a seating surface Torso (Back) Line Line from the H-point through the sliding thoracic pivot (B1 divot point). See SAE J1100. Thigh
29、line A line in side view connecting the H-point to the knee point. See SAE J1100 4. TEST SEAT 4.1 Seat Complete A complete seat created at the intended manufacturing quality shall be used where possible. A prototype seat system or parts may be used in cases where finished parts are not feasible for
30、testing. 4.2 Conditioning The test seat should be conditioned, undeflected, and undistorted at 23 2 C and relative humidity of 50 5% for at least 12 h before being tested. The tests shall be performed 96 h or more after the manufacture of the raw materials used in the test specimen (foam, elastic co
31、mponents other than metal, etc.).Because most seats are made with open-celled foam, loading them forces air out of the foam cells. Full recovery of the foam (movement of air back into the seat to equilibrium levels) requires time. Therefore, it is recommended that seats rest up to four hours between
32、 major tests to recover fully. 4.3 Seat Setup For seats with adjustable track and recline, the test seat should be positioned as specified by the manufacturer. If no setup information is provided, the benchmark SgRP position as described in SAE J4003 should be used. SAE J2896 Issued JAN2012 Page 5 o
33、f 35 4.4 Adjustable Features Any non-standard adjustable features should be set to the manufacturer-specified positions. If no setting is specified, features should be set to the full off or retracted position (e.g.,st lumbar support or shortest thigh extender). NOTE: Tests can be repeated on the sa
34、me seat with the adjustable features at different settings. 5. TEST METHODS 5.1 Overall Load Deflection For many materials, stiffness is a linear relationship which can be represented as a straight line and described with a single parameter. The mechanical behavior of seats is extremely non-linear u
35、nder regular occupant loading conditions and requires more complex parameters to describe the relationship. This test measures the deflection characteristics of motor vehicle seats or foam pads under loading and unloading conditions and provides recommended parameters to be reported from the test re
36、sults. 5.1.1 Test Apparatus 5.1.1.1 Static load deflection measurement systemThe deflection measurement system shall be capable of applying forces up to 1500N at a constant rate and measuring the resulting indenter position. 5.1.1.2 Seat Fixture The seat mounting fixture shall be capable of rigidly
37、securing the test sample in proper position and orientation under all test conditions.5.1.1.3 Indenter (Pressing Plate) One of the following Indenter types with a projected contact area greater than 500cm2and a fixed joint is recommended (Figure 2): a. Seat Cushion: Buttform, Disk, or Oval Pressing
38、Plate b. Seat Back: Backform, Disk, or Oval Pressing Plate FIGURE 1 - EXAMPLE STATIC LOAD DEFLECTION TEST EQUIPMENT SAE J2896 Issued JAN2012 Page 6 of 35 NOTE: If data is to be compared from multiple test facilities it is important to control sources of gage variation including the construction char
39、acteristics of pressing plates). See Appendix B Section B1 NOTE: If a universal swivel joint is used with the buttform or backform, a counterbalance (springs or weight, etc) is required to level the pressing plate and control the approach angle prior to loading. NOTE: Data collected from different i
40、ndenters may not be comparable. see Appendix B Section B1 5.1.2 Setup A light muslin cover of sufficient size to prevent the machine from contacting the seat, approximately 910 mm2, is recommended to avoid marking of the seat and promote smooth movement of the pressing plate. The muslin should be a
41、plain cotton fabric having a thread count and weight typical of a durable, mid-grade, general-purpose muslin that is available from most fabric stores. The test seat shall be mounted as specified in 5.1.2.1 and 5.1.2.2 (Figure 3). 5.1.2.1 Seat Cushion Mount the seat cushion so the applied force is p
42、erpendicular to the thigh line of the HPM Cushion Pan.a. The Oval Type pressing plate should be positioned laterally across the cushion. b. The Buttform pressing plate should be positioned with thighs facing forward. Indenters may need to be offset forward to eliminate interference from the seat bac
43、k.a. For the Oval and Disk Type Indenters this offset is typically measured from the loading point of the Pressing Plate to the targeted Seat H-point.b. For the Buttform this offset is measured from the Buttform Hip Point to the Seat H-point.A standard offset should be applied to ensure equitable co
44、mparisons. The typical standard offset is 40mm forward of the Seat H-point. The historical offset range used in industry has varied from 40mm to 90mm. NOTE: The seat back may also be reclined or adjusted as needed to eliminate additional interference with the indenter. If interference is still evide
45、nt, offset the indenter until it is clear and document the resulting offset. 5.1.2.2 Seat Back Mount the specimen so the applied force is perpendicular to the torso line of the back pan. For seats with a recliner mechanism, brace the seatback during loading to minimize the contribution of the reclin
46、er mechanism to the hardness measurement.a. The Oval Type pressing plate should be positioned vertically on the seat back.b. The Oval and Disk Type should be offset so the loading point corresponds to a predetermined Lumbar Apex measured above the Seat H-point. Typical offset is 150mm above H-point.
47、 The historical offset range used in industry has varied from 100mm to 200mm. c. The Backform pressing plate should be positioned so the equivalent H-point is aligned to the seat H-point.SAE J2896 Issued JAN2012 Page 7 of 35 H-PointZZLoadingPointH-PointZZLoadingPointBackform & SeatH-PointLoadingPoin
48、tZZOVALTYPEDISKTYPEBACKFORMTYPEZ OffsetZ OffsetFIGURE 2A - SEAT BACK PRESSING PLATES LoadingPointX OffsetXXH-PointLoadingPointX OffsetXXH-PointSeat H-PointLoadingPointX OffsetXXOVALTYPEDISKTYPEBUTTFORMTYPEButtform Hip PointFIGURE 2B - SEAT CUSHION PRESSING PLATES LoadDirectionH-PointZFIGURE 3 - SEAT
49、 CUSHION AND SEAT BACK SETUPSAE J2896 Issued JAN2012 Page 8 of 35 5.1.3 Load Force Application The following parameters shall be used for the static load deflection measurement system: Set maximum loading force to: a. Seat Cushion: 1100 N (247.8 lbf) b. Seat Back: 550 N (123.9 lbf) NOTE: These recommended maximum force values are based on Pressing Plates with a projected contact area greater than 500cm2. To prevent undesired seat
