1、Designation: F 2137 04Standard Practice forMeasuring the Dynamic Characteristics of AmusementRides and Devices1This standard is issued under the fixed designation F 2137; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers acquisition of data related to thedynamic characteristics of amusement rides and devices.1.2 Thi
3、s practice also defines the specific requirements of aStandardized Amusement Ride Characterization Test (SARCTest) for use in characterizing the dynamic motion of anamusement ride or device.2. Referenced Documents2.1 SAE Standard:SAE J211 Instrumentation for Impact Tests23. Terminology3.1 Definition
4、s:3.1.1 aliasinga phenomenon associated with sampleddata systems, wherein a signal containing significant energy atfrequencies greater than one half of the system sample fre-quency manifests itself in the sampled data as a lowerfrequency (aliased) signal. Aliasing can be avoided only bylimiting the
5、frequency content of the signal prior to thesampling process. Once a signal has been aliased, it is notpossible to reconstruct the original signal from the sampleddata.3.1.2 calibration constantthe arithmetic mean of the sen-sitivity coefficients, evaluated at frequencies that are evenlyspaced on a
6、logarithmic scale between FLand FH.3.1.3 calibration valuethe ratio of the reference calibra-tion system output, in engineering units relevant to the trans-ducer, to the data channel output, in volts, as measured atconstant excitation frequency and amplitude.3.1.4 channel frequency class (CFC)a freq
7、uency responseenvelope that conforms to Fig. 1 and is referred to by the valueFHin hertz. The CFC frequency response envelope is definedby the boundaries shown in Fig. 1 and the following charac-teristic frequencies:FLPass band lower limit (hertz). Always equal to zero(0.0) hertz.FHPass band upper l
8、imit (hertz). The CFC designator.FNThe corner or knee of the frequency response envelope.Always equal to or greater than 1.667 3 FH.FSThe minimum sample frequency for a sampled datasystem that corresponds to the designated CFC. Always equalto or greater than 12 3 FH.3.1.4.1 DiscussionFL, FH, FN, and
9、 FSare always specifiedin hertz. While the characteristics of the CFC may be appliedto individual components of a data channel, the CFC is, bydefinition, the frequency response envelope of the entire datachannel from the mounted transducer to the final representationof the acquired data.3.1.5 coordi
10、nate systemthree orthogonal axes that inter-sect at an origin whose positive directions correspond to theright-hand rule.3.1.5.1 measurement coordinate systema coordinate sys-tem that provides the reference axes and sign convention forthe test data record(s).3.1.5.2 patron coordinate systema coordin
11、ate system thatis fixed with respect to the human upper torso and oriented asin Fig. 2.3.1.5.3 vehicle coordinate systema coordinate system thatis fixed with respect to the ride or device being tested.3.1.6 data channelthe entire instrumentation system for asingle channel of data acquisition; from t
12、he transducer to thefinal representation of the data, including all post-acquisitiondata processing that may alter the amplitude or frequencycontent of the data.3.1.7 data channel full scalethe maximum usable value,in units of the physical phenomenon being measured, that maybe represented by a data
13、channel. This value is determined bythe data channel component with the lowest full-scale range.3.1.8 free-run timea period of time during the ride cyclewhen no energy is added to the ride vehicle.3.1.9 full-scalethe maximum usable value, in units of thephysical phenomenon being measured, which may
14、be repre-sented by a data channel or some component thereof.3.1.10 “g”the standard acceleration due to gravity at thesurface of the earth. Defined as 32.2 ft/s/s or 9.81 m/s/s.3.1.11 nonlinearitythe ratio, in percent, of the maximumdifference between a calibration value and the corresponding1This pr
15、actice is under the jurisdiction of ASTM Committee F24 on AmusementRides and Devices and is the direct responsibility of Subcommittee F24.10 on TestMethods.Current edition approved May 1, 2004. Published May 2004. Originallyapproved in 2001. Last previous edition approved in 2001 as F 2137 01.2Avail
16、able from Society of Automotive Engineers, 400 Commonwealth Drive,Warrendale, PA 15096.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.value determined from the straight line defined by the sensi-tivity coefficient and zero bias.3.1.
17、12 reference calibration systemthe entire calibrationinstrumentation system from the reference transducer to theoutput device that provides the calibration excitation value inengineering units appropriate to the physical phenomenonbeing measured.3.1.13 resolutionthe lowest magnitude data channel out
18、-put value that can be identified as non-zero.3.1.14 sensitivity coeffcientthe slope of the straight linerepresenting the best fit, as determined by the method of leastsquares, to calibration values generated at a single frequencyand at various amplitudes within the data channel full scalerange. In
19、the special case where only a single calibration valueis considered, the sensitivity coefficient and the calibrationvalue will be equal.3.1.15 standardized amusement ride characterization test(SARC Test)an instrumented test of an amusement ride orFIG. 1 Frequency Response EnvelopeFIG. 2 Patron Coord
20、inate SystemF2137042device that is done in conformance to the general specificationsof this standard and the particular specifications of Section 12.3.1.16 test data recordthe uninterrupted time record ofdata channel value(s) that results from a data acquisitionsession. the length of a data acquisit
21、ion session is not specified.The data acquisition session is considered complete (or inter-rupted) when data is not recorded for a time interval longerthan the sampling period of the data recorder. Both a strip chartpaper record and a computer data file containing periodicallysampled data channel va
22、lues are typical forms of a test datarecord.3.1.17 test documentationthe entire body of documenta-tion pertaining to a test performed in compliance with thispractice, including, but not limited to, the test data record(s),data channel specifications and other test specifications, andinformation as p
23、rovided in this practice (see Section 11 and12.1.9).3.1.18 transducerthe device at the front end of the datachannel that converts a physical phenomenon, such as accel-eration, to a calibrated electrical signal that may be input to theremainder of the data channel.3.1.19 transverse sensitivitythe sen
24、sitivity of a rectilineartransducer to excitation along an axis that is perpendicular toits nominal sensitive axis.3.1.20 zero biasthe magnitude of the data channel outputwhen the transducer input is zero or static.4. Significance and Use4.1 This practice is intended for use whenever the dynamicchar
25、acteristics of an amusement ride or device are to bedetermined. The existence of this practice is not intended toimply that there is a requirement to perform specific testing onamusement rides or devices.4.2 The general provisions of this practice provide instru-mentation specifications, data acquis
26、ition and testing proce-dures, and documentation requirements that when applied willimprove the repeatability, reliability, and utility of the testresults.4.3 Based on the general provisions of this practice, theSARC Test specifications, when followed, will yield standard-ized test results regarding
27、 the patron-related, dynamic motionof amusement rides or devices. The SARC Test will facilitateboth the meaningful comparison of the dynamic motion ofdifferent amusement rides or devices and the tracking ofchanges, if any, in the dynamic characteristics of a given rideor device.5. Data Channel Perfo
28、rmance Specifications5.1 CFC DefinitionsThe following channel frequencyclasses are defined as standard:CFC10ACFC60BFL0.0 Hz 0.0 HzFH10.0 Hz 60.0 HzFN16.7 Hz 100 HzFS120 Hz 720 HzACFC10 should be used when the data channel is being used for acquisition oflower frequency events.BCFC60 should be used w
29、hen the data channel is being used for acquisition ofhigher frequency events.Other channel frequency classes may be defined as needed ordesired by the user of this practice. The proportional relation-ship between FH, FN, and FSshall be maintained for all channelfrequency classes.5.2 Minimum data cha
30、nnel resolution shall be 2 % of thedata channel full scale.5.3 Maximum nonlinearity shall be 2.5 % of the datachannel full scale.5.4 Minimum time base resolution shall be 1/FS(s).5.5 Maximum relative delay or time shift between datachannels that are nominally acquired simultaneously shall be1/FS(s).
31、6. Transducer Performance Specifications6.1 Transducer selection shall be consistent with the in-tended test objectives and generally accepted instrumentationand engineering practice.6.2 The transducer frequency response curve shall conformto the CFC frequency response envelope from FLthrough2 3 FHa
32、nd exhibit no more than +6 dB of peaking at thenatural frequency of the transducer.6.3 Maximum transverse sensitivity shall be 3 %.7. Recorder Performance Specifications7.1 Analog Data Recorders:7.1.1 The analog data recorder shall provide a method bywhich the zero bias, if any, can be reduced to le
33、ss than the datachannel minimum resolution prior to acquiring any test data.7.1.2 Minimum amplitude resolution shall be two 2 % of thedata channel full scale.7.1.3 Paper tape recorders (or their equivalent) shall providea minimum paper speed, in mm/s, of 1.5 3 FH(Hz).7.2 Digital Data Recorders:7.2.1
34、 All data shall be acquired with a minimum CFC of ten.7.2.2 Minimum amplitude resolution shall be 0.10 % of thedata channel full scale.7.2.3 Minimum sample rate shall be FS(Hz) for the chosenCFC.7.2.4 Protection from aliasing errors in the sampled datashall be accomplished by pre-sample filtering th
35、at conforms tothe specified CFC frequency response envelope for the datachannel.7.2.4.1 Alternate protection from aliasing errors may beaccomplished by providing appropriate pre-sample, anti-aliasfiltering in conjunction with a higher-than-FSsample rate anddigital post-acquisition filtering such tha
36、t the frequency re-sponse envelope of the data channel conforms to the desiredCFC frequency response envelope. The anti-alias filter charac-teristics shall be such that the maximum possible signalamplitude at one half the sampling frequency is less than thedata channel minimum resolution.8. Calibrat
37、ion Specifications8.1 For transducers, data recorders, or any other data chan-nel component that is subject to calibration changes over time,the calibration constant and frequency response shall bedetermined and documented annually.8.2 Reference calibration instrumentation used as a second-ary stand
38、ard in the calibration of a data channel or anyF2137043subsystem thereof shall have current certificates of calibrationthat are traceable to accepted national standards.8.3 The reference calibration system and calibration meth-ods shall not introduce a calibration error greater than 1.5 % ofthe data
39、 channel full scale.8.4 To establish a data channel or data channel componentfrequency response and calibration constant, sensitivity coef-ficients shall be determined from calibration values measuredat a minimum of one signal amplitude that represents at least50 % of the full scale range of the dat
40、a channel or componentbeing calibrated and throughout a range of frequencies from FLto 10 3 FHfor a given CFC. A minimum set of five sensitivitycoefficients establishes the frequency response of a data chan-nel or component. The minimum set of sensitivity coefficientsshall be generated at frequencie
41、s that nominally correspond tothe following CFC specifications:FL, FH, FN,23 FH, and 10 3 FN8.5 To establish nonlinearity, a minimum of one sensitivitycoefficient shall be determined from calibration values gener-ated at a minimum of three signal amplitudes that nominallycorrespond to the following
42、percentages of the minimumfull-scale range of the data channel or data channel componentbeing calibrated: Less than 20 % of full scale, 50 % of fullscale, and 80 % of full scale. For the minimum requirement ofa single sensitivity coefficient, the nominal frequency shall behalfway between FLand FH.9.
43、 Transducer Location and Mounting9.1 General Instrumentation:9.1.1 Transducer location, orientation, and mountingmethod shall be consistent with the intended test objectives andgenerally accepted instrumentation and engineering practice.9.1.2 Transducers shall be mounted such that the anglebetween t
44、he sensitive axis (axes) of the transducer and thecorresponding axis (axes) of the selected coordinate systemshall be no greater than 5.9.2 General Accelerometry:9.2.1 MountingTo avoid distortion in the data channelvalues, accelerometers shall be mounted so as to minimizerelative motion between the
45、transducers and the instrumentedsurface. When deemed appropriate, an analytical or experimen-tal evaluation of transducer mounting effects on the datachannel should be provided (see 11.1.6).9.2.2 When multi-axis accelerations at a point are to bemeasured, the center of seismic mass of each accelerom
46、etershall be within 60 mm of that point. Each accelerometer axisshall be within one degree of orthogonal relative to the otheraxes.10. Procedure10.1 The unique characteristics of a particular amusementride or device or other special circumstances may be such thatit is not reasonably possible to test
47、 in strict conformance withone or more provisions of this practice. Any deviation(s) fromthe provisions of this practice shall be recorded so as to clearlyprovide a description of the specific deviation(s).10.2 Field Calibration:10.2.1 Where practical, all data channels should be sub-jected to a fie
48、ld calibration procedure to establish the reliabilityof the data channel calibration.10.2.2 For accelerometer-based data channels, the fieldcalibration procedure, may take the form of a 2g “roll-over”test. The 2g “roll-over” test requires that the accelerometer beplaced with its sensitive axis perpe
49、ndicular to a plane surfacethat is nominally level with respect to the earth while the outputof the data channel is recorded. The accelerometer should thenbe oriented with its sensitive axis parallel to this surface torecord a zero-g input. Next, the accelerometer should beinverted with respect to its original orientation and its outputrecorded. This procedure will yield a three-point calibration(+1g,0g, and -1g) with a nominal 2g range.10.3 When testing the nominal dynamic characteristics ofamusement rides and devices that have characteristics thatchang
