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 2009 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: 724-776-4970 (outside USA)
4、 Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SURFACE VEHICLE INFORMATION REPORT J2570 AUG2009 Issued 2001-09 Revised 2009-08 Superseding J2570 SEP2001 (R) Performance Specifications for Anthropomorphic Test Device Transducers RATIONALE This document was created
5、 to define the minimum requirements of transducers for use in regulated locations within the ATD. It is being revised to: 1) Add or update devices required in current FMVSS safety compliance testing. 2) Address terminology concerns of the ISO committee for safety compliance testing. 3) Add a comment
6、 on the usage of damped accelerometers as an alternative to undamped accelerometers in safety testing. 1. SCOPE This SAE Information Report defines the minimum performance specifications for accelerometers, load cells, and angular position transducers used within Anthropomorphic Test Devices (ATDs)
7、when performing impact tests per SAE J211, “Instrumentation for Impact Test”. This report does not define methodology and equipment for performing verification tests of the transducers. It is intended that any agency proposing to conduct tests in accordance with SAE J211 shall be able to demonstrate
8、 that the transducers they use would meet the performance requirements specified in this document. 1.1 Purpose The purpose of this document is to provide guidelines for choosing accelerometers, load cells, and angular position transducers for use in impact testing. The aim is to provide uniformity i
9、n transducer measurements, and provide a basis for meaningful comparisons of test results from different sources. 1.2 Field of Application The transducer specifications defined in this document apply in particular to those transducers used within ATDs, and whose outputs are used to calculate various
10、 injury estimates. The transducer specifications also apply to sensors used for the calibration of ATDs. 2. REFERENCES 2.1 Applicable Publications The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publicat
11、ions shall apply. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHSSAE J2570 Revised AUG2009 Page 2 of 15 2.1.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 150
12、96-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. SAE J211-1 Instrumentation for Impact TestPart 1Electronic Instrumentation SAE J1733 Sign Convention for Vehicle Crash Testing 2.1.2 National Highway Traffic Safety Administration (NHTSA) Publications Avai
13、lable from NHTSA Headquarters, 1200 New Jersey Avenue, SE, West Building, Washington, D.C. 20590, Tel: 1-888-327-4236, www.nhtsa.gov. Code of Federal Regulations, Title 49, part 572 (CFR part 572) Appropriate NHTSA Dockets, Notice of Proposed Rule Making (Proposed Amendments to CFR part 572) 2.1.3 M
14、ilitary Specifications Available from the Document Automation and Production Service (DAPS), Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Tel: 215-697-6257, http:/assist.daps.dla.mil/quicksearch/. MIL-PRF-39023B (1 February 1999) General Specification for Precision Nonwire-wound Re
15、sistors MIL-STD 45662A (1 August 1988) Calibration System Requirements 2.1.4 ANSI Publications Available from ANSI, 25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org. ANSI/NCSL Z540-1-1994 Calibration Laboratories and Measuring and Test EquipmentGeneral Requirements 3. DE
16、FINITIONS 3.1 Load Cell Definitions 3.1.1 Channel Frequency Class (CFC) The channel frequency class is designated by a number indicating that the channel frequency response lies within limits specified by Figure 1 of SAE J211-1. This must be defined to calculate free air resonance. 3.1.2 Compensated
17、 Temperature Range The range of temperature over which the transducer is compensated to maintain output and zero balance within specified limits. 3.1.3 Crosstalk Effect on the reading of an unloaded transducer axis when a load equal to the full-scale capacity of a secondary axis is applied to that s
18、econdary axis. Expressed as a percentage of full-scale capacity of the unloaded axis. 3.1.4 Deflection at Full Scale Applied Load Maximum linear deflection of a load cell in the direction of the applied full scale load for that axis. Copyright SAE International Provided by IHS under license with SAE
19、Not for Resale-,-,-SAE J2570 Revised AUG2009 Page 3 of 15 3.1.5 Deflection at Full Scale Applied Moment Maximum angular deflection of a load cell in the direction of the applied full scale moment for that axis. 3.1.6 Free Air Resonance The frequency at which a transducer resonates, when suspended fr
20、eely in air by a single wire and impacted with a hard surfaced body. This test shall be done while monitoring the channel output to insure each channels fundamental output frequency shall be equal to or greater than the specified frequency. 3.1.7 Full Scale Capacity Full scale capacity refers to the
21、 capacity defined in CFR part 572. This must be defined for calculating other parameters in these specifications. 3.1.8 Hysteresis (% of Full Scale Capacity) The maximum deviation between ascending and descending output readings taken at the same load point, expressed as a percentage of full scale c
22、apacity. Refer to Figure 1 for graphical representation. 3.1.9 Non-Linearity (% of Full Scale Capacity) The maximum deviation of a transducer output reading from the terminal line, expressed as a percentage of full scale capacity (the terminal line is defined as a straight line connecting a transduc
23、er zero load reading and its full scale reading). Refer to Figure 1 for graphical representation. 3.1.10 Temperature Effects on Output The change in output due to a change in transducer temperature, expressed as a percentage of reading per degree Celsius change. Refer to Figure 1 for graphical repre
24、sentation. 3.1.11 Temperature Effects on Zero Balance The change in zero balance due to a change in transducer temperature, expressed as a percentage of full scale capacity per degree Celsius change. Refer to Figure 1 for graphical representation. 3.1.12 Terminal Line A theoretical straight line con
25、necting a transducer zero load reading and its full scale reading. Refer to Figure 1 for graphical representation. NOTE: The ISO committee refers to this as “Sensitivity Coefficient”. Copyright SAE International Provided by IHS under license with SAENot for Resale-,-,-SAE J2570 Revised AUG2009 Page
26、4 of 15 FIGURE 1 - TYPICAL SENSOR CALIBRATION CURVES 3.2 Accelerometer Definitions 3.2.1 Compensated Temperature Range The range of temperature over which the transducer is compensated to maintain output and zero balance within specified limits. 3.2.2 Damping Ratio The ratio of a transducer output v
27、s. input when excited by a sinusoidal input near the point of resonance. A reasonably accurate calculation for damping ratio is a ratio of measured sensitivity at near DC versus 2 times the measured sensitivity at resonance. This assumes that resonance is defined at the 90-degree phase shift point.
28、3.2.3 Frequency Response The range of frequencies over which the transducer output voltage will follow the sinusoidally varying mechanical input within specified limits. The difference in sensitivity at any frequency relative to the sensitivity at a set frequency in the range of 80 to 160 Hz is spec
29、ified as a percentage of the sensitivity measured at that set frequency. 3.2.4 Full Scale Range Full scale range as is listed in CFR part 572, or in the appropriate NPRM (Notice of Proposal Rule Making). This must be defined for calculating other parameters in these specifications. 3.2.5 Non-Lineari
30、ty (% of Reading) The maximum deviation of a transducer output reading from the terminal line, expressed as a percentage of reading. The terminal line is defined as a straight line connecting a transducer zero load reading and its full scale reading. Refer to Figure 1 for graphical representation. C
31、opyright SAE International Provided by IHS under license with SAENot for Resale-,-,-SAE J2570 Revised AUG2009 Page 5 of 15 3.2.6 Resonance Frequency The resonance frequency is the frequency at which the voltage output of an accelerometer lags the mechanical input by a phase angle of 90 degrees. For
32、undamped accelerometers, it may alternately be defined as the frequency at which the response (sensitivity) of an accelerometer is at its maximum output. 3.2.7 Sensitivity or Sensitivity Coefficient The ratio of the output signal (in equivalent physical units) to the input signal (physical excitatio
33、n) when an excitation is applied to the transducer. This may be determined from a single point or a regression of evenly spaced points, as specified for the transducer. 3.2.8 Temperature Effects on Output The change in output due to a change in transducer temperature, expressed as a percentage of re
34、ading per degree Celsius change. Refer to Figure 1 for graphical representation. 3.2.9 Temperature Effects on Zero Balance The change in zero balance due to a change in transducer temperature, expressed as a percentage of full scale range per degree Celsius change. Refer to Figure 1 for graphical re
35、presentation. 3.2.10 Terminal Line A theoretical straight line connecting a transducers zero load reading and its full scale reading. Refer to Figure 1 for graphical representation. 3.2.11 Transverse Sensitivity The output of the sensitive axis due to any acceleration applied orthogonally to that ax
36、is, specified as a percentage of applied acceleration. 3.2.12 Zero Repeatability When any shock pulse is applied in the primary direction and within the specified range of an accelerometer, the zero output shall return to its initial value. 3.3 Angular Displacement Transducer Definitions 3.3.1 Compe
37、nsated Temperature Range The range of temperature over which the transducer is compensated to maintain rated output and zero balance within specified limits. 3.3.2 Minimum Electrical Angle The specified shaft travel over which the functional characteristic extends between defined output ratio limits
38、, as determined from the index point. 3.3.3 Minimum Rotational Speed The minimum rotational speed at which the transducer must operate while maintaining its specified performance. Copyright SAE International Provided by IHS under license with SAENot for Resale-,-,-SAE J2570 Revised AUG2009 Page 6 of
39、 15 3.3.4 Non-Linearity The maximum deviation, expressed in degrees, of the actual functional characteristic from a fully defined straight reference line. 3.3.5 Output Smoothness A measurement of any spurious variation in the electrical output that is not present in the input, expressed in degrees.
40、3.3.6 Shaft End Play The total axial excursion of the shaft, measured at the end of the shaft with a specified axial load supplied alternately in opposite directions, expressed in inches. 3.3.7 Shaft Radial Play The total radial excursion of the shaft, measured at a specified distance from the front
41、 surface of the unit, expressed in length (inches or millimeters). A specified radial load is applied alternately in opposite directions at a specific point. 3.3.8 Shaft Run-out The eccentricity of the shaft diameter with respect to the rotational axis of the shaft, measured at a specified distance
42、from the end of the shaft, with a specified radial load applied to the shaft. 3.3.9 Shock Discontinuity The maximum period of time that the transducer may experience any electrical output discontinuity caused by subjecting the transducer to 100 g, half sine pulse of 11 ms duration in any direction.
43、3.3.10 Terminal Line A theoretical straight line connecting a transducer zero load reading and its full scale reading. Refer to Figure 1 for graphical representation. 3.3.11 Temperature Effects on Output The change in output due to a change in transducer temperature, expressed as a percentage of rea
44、ding per degree Celsius change. 3.3.12 Temperature Effects with No Rotation The change in output with no rotation due to a change in transducer temperature, expressed in degrees. 3.4 Angular Rate Sensor Definitions 3.4.1 Load / Loading The physical input to the transducer in the form it was designed
45、 to measure. For example; the load to an angular velocity sensor may have units of deg/sec while the load to an angular accelerometer may have units of deg/sec/sec. 3.4.2 Bandwidth For a digital system bandwidth is determined by the maximum sample rate of the output. For an analog device the bandwid
46、th is defined by the maximum rate of change to the input load which can be measured, within a specified accuracy tolerance, expressed in Hertz. Copyright SAE International Provided by IHS under license with SAENot for Resale-,-,-SAE J2570 Revised AUG2009 Page 7 of 15 3.4.3 Compensated Temperature Ra
47、nge The range of temperature over which the transducer is compensated to maintain output and zero balance within specified limits. 3.4.4 Cross Axis Sensitivity The output of the transducer due to a loading applied orthogonally to the measured axis, specified as a percentage of the applied load. 3.4.
48、5 Full Scale Range Full scale range as is listed in CFR part 572, or in the appropriate NPRM. This must be defined for calculating other parameters in these specifications. 3.4.6 Influence of Linear Acceleration The maximum change in output caused applying a linear acceleration on any axis, expressed in deg/sec/g for angular velocity transducers and deg/sec/sec/g for angular acceleration transducers. 3.4.7 Noise The amplitude of unwanted electrical energy which degrades the quality of the output signal and data. Noise is in part related to the bandwidth of the transducer, and must be eval
