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 there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2011 SAE International All rights reserved. No part of this publication m
3、ay 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 (outside U
4、SA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, please visit http:/www.sae.org/technical/standards/J2114_201102SURFACEVEHICLERECOMMENDEDPRACTICEJ2114 FEB2011 Issued 1993-04 Stabilized 2011-02 Su
5、perseding J2114 OCT1999 Dolly Rollover Recommended Test Procedure RATIONALE The technical report covers technology, products, or processes which are mature and not likely to change in the foreseeable future. STABILIZED NOTICE This document has been declared “Stabilized“ by the SAE Impact and Rollove
6、r Test Procedure Standards Committee and will no longer be subjected to periodic reviews for currency. Users are responsible for verifying references and continued suitability of technical requirements. Newer technology may exist. Copyright SAE International Provided by IHS under license with SAENot
7、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2114 Stabilized FEB2011 Page 2 of 5 ForewordThe objective of this procedure is to subject a test vehicle to a rollover condition. The vehicle andoccupant dynamics are recorded using appropriate instrumentation and p
8、hotographic/video coverage such thatthe vehicle and occupant kinematics can be observed.1. ScopeThis SAE Recommended Practice describes the test procedure for conducting a rollover test using adolly fixture designed to laterally trip a vehicle into a roll. Its purpose is to establish a recommended t
9、estprocedure which will standardize the procedure between different test facilities. A description of the testprocedure, test instrumentation, photographic/video coverage, and the rollover fixture is included.2. References2.1 Applicable PublicationsThe following publications form a part of the speci
10、fication to the extent specifiedherein. Unless otherwise indicated, the latest revision of SAE publications shall apply.2.1.1 SAE PUBLICATIONAvailable from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J211-1Instrumentation for Impact TestPart 1: Electronic Instrumentation2.1.2 ASTM PUB
11、LICATIONAvailable from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.ASTM E 274-90Standard Test Method for Skid Resistance of Paved Surfaces Using a Full-Scale Tire3. Test Facilities3.1 Test SiteThe test site and facilities should be able to tow and guide the rollover dolly to a cons
12、tant velocity,decelerate the dolly, and allow for free unobstructed rolling of the test vehicle until it comes to rest. Typically,the test site will be an outdoor, concrete, level surface with a guide rail, towing system, and an energy-absorbing snubber which will decelerate the moving dolly appropr
13、iately.The surface, on which the vehicle will be tripped, and initially contact should be of a uniform concreteconstruction with a skid number of 75 when tested according to ASTM E 274-90 at 64.4 km/h (40 mph),omitting water delivery as specified in paragraph 8.1 of that method. Typically for a 48 k
14、m/h (30 mph) initialvelocity, a surface which allows for 50 m (164 ft) of unobstructed rolling is sufficient for most passenger carapplications.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J21
15、14 Stabilized FEB2011 Page 3 of 5 3.2 Dolly Rollover FixtureThe rollover fixture is constructed such that during its deceleration the test vehicle istripped into a lateral unobstructed roll on the concrete surface. A diagram of a typical rollover fixture isincluded in Figure 1. The incline is at 23
16、degrees to the horizontal, and the lower flange, which trips the tires ofthe test vehicle, is 102 mm (4 in) deep measured from the top of the flange to the top of the inclined surface. Itshould be noted that the tire and rim interaction with the flange will depend upon the type of tire and will not
17、beconsistent for all vehicles. The intersection of the inner side of the flange and the top of the inclined surfaceshould be 229 mm (9 in) above the concrete roll surface. The fixture should be constructed such that it will notpitch severely during the deceleration. One method of limiting the pitch
18、is to utilize wheels which extendforward of the location of applied stopping force which will prevent severe rotation about the center of gravity.In addition, the rear of the dolly may be vertically constrained to the tow rails to prevent pitch.FIGURE 1DOLLY ROLLOVER FIXTUREA remote-controlled brake
19、 system should be installed on the fixture to allow for the test to be aborted followingthe beginning of the fixture tow. Moderate braking levels, as opposed to typical higher abort braking levels withbarrier testing, may be necessary to maintain vehicle stability with a narrow track, high center of
20、 gravityvehicle.The rollover fixture must be guided in a straight path during its acceleration and allowed to reach a constantvelocity before deceleration. The vehicle must be motionless relative to the fixture before the deceleration ofthe fixture begins. Deceleration parameters should be chosen su
21、ch that the vehicle leaves the dolly fixtureappropriately. As an example, if the initial velocity is chosen to be 48 km/h (30 mph), a minimum decelerationrate of 20 g for at least 40 ms and allowing no more than 91 cm (3 ft) of dolly travel would be appropriate.Accelerometers should be mounted on th
22、e fixture to record the deceleration pulse. If energy-absorbingmaterial is used to stop the fixture, it must exert adequate forces on the fixture to produce the desireddeceleration rate.The vehicle should be placed on the fixture with the vehicles center of gravity centered between the tires of thef
23、ixture. The test vehicles brakes are disengaged and the transmission placed in neutral. Care should betaken when placing the vehicle on the dolly so as to not significantly deform the tires laterally. Sliding thevehicle down into position should be avoided to insure the appropriate tire condition wh
24、en it is resting againstthe flange.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2114 Stabilized FEB2011 Page 4 of 5 4. Photographic or Video CoverageTypical passenger vehicles can be expected
25、 to roll between 2-1/2 and4 rolls lasting from 4 to 6 s. High-speed movie cameras or video cameras should be used to document thetest. The camera layout is indicated in Figure 2.FIGURE 2PHOTOGRAPHIC COVERAGE(NOTE2 ONBOARD CAMERAS NOT SHOWN) At least nine high-speed movie cameras (240 frame/s) or vid
26、eo cameras are needed as well as a lower-speedmovie camera or video recorder. Four high-speed cameras are mounted on the front of vehicle side of the rollat 10 m (33 ft) intervals, with each cameras field of view overlapping with the adjacent camera(s). The firstcameras field should cover the vehicl
27、e leaving the dolly. Two high-speed cameras are located on each side ofthe fixture and follow the vehicles roll during the test. One high-speed camera is used at the end of the rollpath pointing back toward the fixture. At least two high-speed cameras which are shock mounted and fittedwith wide angl
28、e lenses may be mounted in the interior of the vehicle to record occupant motion during therollover. The lower-speed camera should be placed on one side of the roll path and should follow the vehicleas it rolls. One or more strobes to indicate the time at which the dolly begins to decelerate should
29、be in thefield of view of all cameras. A timing signal should be recorded on all high-speed cameras.5. Instrumentation5.1 Vehicle DynamicsThe test vehicle is instrumented with accelerometers to record the acceleration in thelateral and vertical (relative to the vehicle) directions. The vehicle accel
30、erometers are typically mounted on theinside surface of the B pillar vertically in line with the center of gravity. Other vehicle accelerometers may beincluded; however, caution should be used to avoid locating accelerometers in areas where large deformation isexpected, which may result in nonrepres
31、entative acceleration signals. In addition to the vehicle accelerometers,an angular velocity transducer is used to record the rotational velocity during the test. This transducer should bemounted as close to the center of gravity as possible and in the longitudinal center of the vehicle.Copyright SA
32、E International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2114 Stabilized FEB2011 Page 5 of 5 The data should be processed and plotted for the entire test duration (up to 6 s). The roll velocity can beintegrated to g
33、enerate an angular displacement time history which can be compared to the vehicleaccelerations and high-speed film to determine the kinematics of the vehicle roll. All instrumentation and dataprocessing should conform to SAE J211-1.6. Notes6.1 Marginal IndiciaThe change bar (l) located in the left m
34、argin is for the convenience of the user in locatingareas where technical revisions have been made to the previous issue of the report. An (R) symbol to the leftof the document title indicates a complete revision of the report.PREPARED BY THE SAE IMPACT AND ROLLOVER STANDARDS COMMITTEECopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
