1、Secretariat Acoustical Society of America American Society of Mechanical Engineers American National Standards Institute, Inc. ANSI S2.2-1959 American National Standard Methods for the Calibration of Shock and Vibration Pickups American National Standard Published by Approval of an American National
2、 Standard requires verification by ANSI that the requirements for due process, consensus, and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly
3、 and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution. The use of American National Standards is comp
4、letely voluntary; their existence does not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Standards Institute does not develop
5、standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpretations sh
6、ould be ad dressed to the secretariat or sponsor whose name appears on the title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to re
7、affirm, revise, or withdraw this standard. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. American National Standards Institute 11 West 42nd Street, New York, New York 10036 Copyright 1960 by
8、 American National Standards Institute All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. Printed in the United States of America Foreword (This Fore9o“ord is not a part of
9、 American Standard1Methods for the Calibr:otion of Shock and Vibration Pickups, 82.2-1959.) This American Standard1 comprises a part of a group of definitions, .standards, and specifica tions for use in work concerning acoustics, vibration, and mechanical shock. It has been developed under the Secti
10、onal Committee Method of ASA procedure, under the co-sponsorship of the Acous tical Society of America and the American Society of Mechanical Engineers. The S2 Committee under whose jurisdiction this standard was developed has the following scope: Standards, specifications, methods of measurement an
11、d test, and terminology in the fields of mechanical shock and vibration, but excluding those aspects that pertain to biological safety, tolerance, and comfort. Various subcommittees have been organized to take care of the committees program and this standard was developed by Subcommittee S2-W -27, w
12、hose personnel is shown below. Suggestions for improvement gained in the use of this standard will be welcomed. They should be sent to the United States of America Standards b1stitute, Ill East 40th Street, New York. N.Y. York 1f The organizations which participated in this work and the names of the
13、ir representatives, as listed at the time this standard was submitted to the S2 Sectional Committee for approval, were as follows: H. M. TnExT, Chairman C. E. CREDE, Vice-Chairman S. DAVID HoFFMAN, Secretary Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14、 8 2.5 Sensitivity, Amplitude Sensitivity, Phase Lag. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.6 Amplitude Distortion, Frequency Distortion, Proportional Phase Lag, Phase Distortion 8 2.7 Calibration Factor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.8 Transverse Sensitivity Ratio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.9 Fxciter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16、. . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.10 Damping Ratio. 9 2.11 Undamped atural Frequency :. 9 2.12 Damped atural J.orequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.13 Resouant Jorequency. . . . . . . . . . . . . . . . . . . .
17、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3. ChanLCteristics to be .Measured. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
18、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.2 Direct Response . . . . . . . . . . . . . . . . . 9 3.:l Response to Motion in Other Directions and About Other Axes. . . . . . . . . . . . . . . . . . . . . . 10 3.4 Damping Ratio and Undamped atural Frequency . 10
19、3.5 Xonlinearity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4. Standard Calibration Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.1 T
20、abulation of Standard Methods . 13 4.2 Tilting Support Calibrator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.3 Centrifuge Calibrator . 14 4.4 Rectilinear Electrodynamic Vibration Pickup Calibrator. . . . . . . . . . . . . . . . . .
21、 . . . . . . . . . . 15 4.4.1 Sensitivity of Electrodynamic Calibrator Determined by Reciprocity :Method. . . . . . 16 4.4.2 Calibration of Vibration Pickups on Calibrator, General llethod . . . . . . . . . . . . . . . . 17 4.5 Physical Pendulum Calibrator. . . . . . . . . . . . . . . . . . . . . .
22、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.6 Ballistic Pendulum Calibrator . 20 5. Calibration by Comparison Vith Calibrated Pickup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Appendix AI. Survey of Other Calibration llethods. . . . . . . . . . . .
23、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Al.l Static Calibration Methods . 23 Al.l.l Static Load Method . 23 Al.2 Dynamic Calibration by Sinusoidal Excitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Al.2.1 Rectilinear Vibration Exciter. . . . . .
24、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 A1.2.2 Angular Vibration Exciter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Al.2.3 Tilted Centrifuge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、 . . . . . . . . . . 26 A1.2.4 Dual Centrifuge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 A1.2.5 Resonant Beam Vibrator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Al.2.6 Acoustical Cavity :
26、Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Al.2.7 Condenser Microphone llethod : . . . 27 A 1.3 Dynamic Calibration by Transient Excitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Al.3.I Free-Fall Test . 28 A1.3.2 Pulse
27、Calibrator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 .-1.3.3 Air Gun . 29 AI.3.4 Shock Test Applying Measured Impact AcceJeration . . . . . . . . . . . . . . . . . . . . 29 A1.3.5 Hydraulic Shock Test . . . . . . . . . . . . . . . . . .
28、 . . . . . . . . . . . . . 30 A1.3.6 Impact Drop Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Al.3. 7 Elastic Pulses in Long Bars. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 A2. Theory of Reciproc
29、ity Method for Linear Electromechanical Pickups. . . . . . . . . . . . . . . . . 30 A3. Reciprocity Method for Electrodynamic Calibrators . . . . . . 32 A3.1 Theory . 32 A3.2 MeasureJnents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30、. . . . 34 A3.2.1 Transfer Admittance !feasurements 35 A3.2.2 Voltage Ratio Measurements . . . . . . . . . . . . . . . . . . . . . 35 Table 1 Estimated Ranges and Errors of Standard Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figures Fig. 1 Response of Idealized Linear Acce
31、leration Pickup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Fig. 2 Response of Idealized Linear Displacement or Velocity Pickup . . . . . . . . . . . . . . . . . 11 Fig. 3 Phase Lag of Idealized Linear Pickup. . . . . . . 11 Fig. 4 Response of Idealized Linear Pickup to a Sudden Impu
32、lse . . . . . . . . . . . . . . . . . . . . . 12 Fig. 5 Tilting Support for Static Calibration of Acceleration Pickups. . . . . . . . . . . . . . . . . . 14 Yg. 6 Schematic Cross-aectionaJ View of Rectilinear Electrodynamic Vibration Pickup Calibrator. . . . . . . . . . . . . . . . . . . . . . . . .
33、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Fig. 7 Circuit for Calibration by Method A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Fig. 8 Pendulum Calibrator 19 Fig. 9 Recorded Output of Pickup on Physical Pendulum Calibrator. . . . .
34、 . . . . . . . . . . . . . 20 Fig. 10 Calibration of Pickup A on Ballistic Pendulum Calibrator 20 Fig. 11 Simple RC Network for Integrating Pickup Output. . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Fig. 12 Compariaon Method for Calibrating Pickup 2 Against Calibrated Pickup 1. . . . . .
35、. 21 Fig. AI Vibrating Wedge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Fig. A2 Rectilinear Vibration Pickup Calibrator with Piezoelectric Drive. . . . . . . . . . . . . . . . 25 Fig. A3 Dual Centrifuge. . . . . . . . . . . .
36、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Fig. A4 Reeona.nt Beam Vibrator. . . . . . . . . . . . . . . . 27 Fig. A5 Impact Load Acting on Mass and Displacement of Mass of Linear Mass-Spring System, with Natural Period T. . . . . . . . . . . . . .
37、 . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Fig. A6 Typical Oscillograph Record from Free-Fall Test of Velocity Pickup 29 Fig. A7 Shock Test Applying Measured Impact Acceleration 29 Fig. A8 Circuits and Polygons for Making Transfer Admittance Measurements on Electro-dynamic Calibrator
38、and Pickups. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Fig. A9 Circuits and Polygons for Making Voltage Ratio Measurements on Electrodynamic Calibrator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
39、. . . . 36 References . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 USA Standard Methods for the Calibration of Shock and Vibration Pickups Introduction The calibration of shock and vibration pickups has
40、 become increasingly important as the need has grown for accurate measurements of the shocks and vibrations to which aircraft, missiles, and other high performance equipment are subjected in service. Numerous methods have been used or proposed for these calibrations. These are briefly described in S
41、ection 4 of this standard and in the Appendix. Section 4 contains a tabulation and detailed descrip tion of five “standard methods“ which have proven themselves to be reliable means for the calibration of shock and vibration pickups. A tabulation (see 4.1) lists approximate ranges of application of
42、each standard method and estimates of attainable ac curacy. The description, which follows the tabula tion, gives details of performing calibrations by each of the standard methods. SectionAl contains a brief survey of other methods which have been used to calibrate vibration pickups, but which have
43、 not found sufficient acceptance as yet to be included among the standard methods. The methods de scribed range from precision techniques suitable for laboratory use only to procedures appropriate to field use. It is anticipated that the standard will undergo frequent vision to keep pace with the ad
44、vance ment of the art in this new and growing field. Section 4 will grow as methods in Section Al prove their adequacy as standards. Section Al will expand as new methods make their appearance. Calibration methods for both shock and vibration pickups are included in the same standard because it is i
45、mpracticable to draw a line of demarcation be tween pickups used in measurements of shocks and vibrations. Using Fourier analysis 1)1 any shock can be described by the superposition of a sufficient number of sinusoidal vibrations of proper fre quency, amplitude, and phase angle. The standard is limi
46、ted to the calibration of ac celeration, velocity, and displacement pickups. It is not concerned with pickups used for measurements of force, pressure, or strain even though some of these may be calibrated by similar methods. 1 Numbers in brackets denote references at the end of the standard. 6 I. P
47、urpose and Scope 1.1 Purpose. This standard is designed to acquaint the user with the general principles of calibration of shock and vibration pickups and to describe con cisely several standard methods which have proven to give reliable and reproducible results. Further de tails concerning these me
48、thods are given in the Appendix. Also, other methods that have not as yet reached the stage of development of the standard methods are described briefly in the Appendix. 1.2 Scope. Five methods have. been selected as standard methods for the calibration of acceleration velocity, and displacement pic
49、kups. They are de scribed in Section 4 of this standard. It is impracticable to calibrate all pickups by one standard method over the entire frequency and amplitude range of vibrations and shocks to be measured by the pickups. Several methods are ac cordingly described. Each method is limited to u range of frequency and amplitude, and to the weight ?f picku that C:S. be calibrated. The limitations may mclude, m addit1on, other variables such as volume of the pickup and temperature of operation. 1.3 Present and Future Choices of Methods. A pickup should be
