STANDARD

ASABE is a professional and technical organization, of members worldwide, who are dedicated to advancement ofengineering applicable to agricultural, food, and biological systems. ASABE Standards are consensus documentsdeveloped and adopted by the American Society of Agricultural and Biological Engineers to meet standardizationneeds within the scope of the Society; principally agricultural field equipment, farmstead equipment, structures, soiland water resource management, turf and landscape equipment, forest engineering, food and process engineering,electric power applications, plant and animal environment, and waste management.

NOTE: ASABE Standards, Engineering Practices, and Data are informational and advisory only. Their use byanyone engaged in industry or trade is entirely voluntary. The ASABE assumes no responsibility for results attrib-utable to the application of ASABE Standards, Engineering Practices, and Data. Conformity does not ensurecompliance with applicable ordinances, laws and regulations. Prospective users are responsible for protectingthemselves against liability for infringement of patents.

ASABE Standards, Engineering Practices, and Data initially approved prior to the society name change in July of2005 are designated as ‘ASAE’, regardless of the revision approval date. Newly developed Standards, EngineeringPractices and Data approved after July of 2005 are designated as ‘ASABE’.

Standards designated as ‘ANSI’ are American National Standards as are all ISO adoptions published by ASABE.Adoption as an American National Standard requires verification by ANSI that the requirements for due process,consensus, and other criteria for approval have been met by ASABE.

Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement hasbeen reached by directly and materially affected interests. Substantial agreement means much more than a simplemajority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that aconcerted effort be made toward their resolution.

CAUTION NOTICE: ASABE and ANSI standards may be revised or withdrawn at any time. Additionally, proceduresof ASABE require that action be taken periodically to reaffirm, revise, or withdraw each standard.

Copyright American Society of Agricultural and Biological Engineers. All rights reserved.

ASABE, 2950 Niles Road, St. Joseph, MI 49085-9659, USA ph. 269-429-0300, fax 269-429-3852, hq@asabe.org

ASABE/ISO 5008:2002Agricultural wheeled tractors and field machinery—Measurement of whole-body vibration of the operator

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …ASABE STANDARDS 2006 1

ASABE/ISO 5008:2002 W/Cor. 1 (Adopted by ASABE MAY 2006)Approved May 2006 as an American National Standard

Agricultural wheeled tractors and field machinery—Measurement of whole-body vibration of the operator

This standard was reviewed for adoption by the ASABE Power andMachinery Agricultural Machinery—Common Tests Technicalsubcommittee, and has been formally approved by the TechnicalCommittee. The adoption of this standard was made possible by thesigning of 2004 SAE-ASABE copyright agreements, which gave ASABEa royalty-free license to publish in whole or in part SAE standarddocument J1013. Adopted by ASABE May 2006. Approved as anAmerican National Standard May 2006.

Keywords : Operator, Seat, Tractors, Vibration

0 Forward0.1 ASABE/ISO 5008:2002, Agricultural wheeled tractors and fieldmachinery—Measurement of whole-body vibration of the operator, is anadoption without modification of the identically titled ISO standard ISO5008:2002, Agricultural wheeled tractors and field machinery—Measurement of whole-body vibration of the operator.This ISO standard is a derivative of SAE J1013, Measurement of WholeBody Vibration of the Seated Operator of Off-Highway Work Machines.0.1.1 The following Technical Corrigendum to ISO 5008:2002 wasreviewed for adoption by the ASABE Power and Machinery AgriculturalMachinery—Common Tests Technical Subcommittee and has beenformally approved by the Technical committee.0.1.1 1 ISO 5008:2002/Cor.1:20050.2 Scope for ASABE/ISO 5008:2002 W/Cor. 1:2005:l Specifies methods for measuring and reporting the whole body

vibration to which the operator of an agricultural wheeled tractor orother field machine is exposed when operating on a standard testtrack.

l The operating conditions of the machine and the ordinates of theartificial test tracks are also included.

l This International Standard applies when measurements are made onthe artificial test tracks defined herein.

l Measurements made under field conditions are covered in annex A.l This International Standard does not include assessment of vibration

reaching the operator other than through his/her seat or foot platform(e.g., vibration that is sensed by the feet through the controls or bythe hands through the steering wheel is not considered).

0.3 Seven normative references are listed in ISO 5008:2002. Thesereferences have been reviewed and accepted as part of the adoption ofASABE/ISO 5008:2002 W/Cor.1:2005.0.4 This standard had been approved as an American National standardby ANSI (American National Standard Institute).

1 Scope1.1 This International Standard specifies methods for measuring andreporting the whole body vibration to which the operator of an agriculturalwheeled tractor or other field machine is exposed when operating on astandard test track.1.2 The operating conditions of the machine and the ordinates of theartificial test tracks are also included.1.3 This International Standard applies when measurements are madeon the artificial test tracks defined herein.1.4 Measurements made under field conditions are covered in annex A.1.5 This International Standard does not include assessment of vibration

reaching the operator other than through his/her seat or foot platform(e.g., vibration that is sensed by the feet through the controls or by thehands through the steering wheel is not considered).

2 Normative referencesThe following normative documents contain provisions which, throughreference in this text, constitute provisions of this International Standard.For dated references, subsequent amendments to, or revisions of, any ofthese publications do not apply. However, parties to agreements basedon this International Standard are encouraged to investigate thepossibility of applying the most recent editions of the normativedocuments indicated below. For undated references, the latest edition ofthe normative document referred to applies. Members of ISO and IECmaintain registers of currently valid International Standards.ISO 2041:1990, Vibration and shock—VocabularyISO 2631-1:1997, Mechanical vibration and shock—Evaluation of humanexposure to whole-body vibration—Part 1: General requirementsISO 5007:1), Agricultural wheeled tractors—Operator’s seat—Laboratorymeasurement of transmitted vibrationISO 5348:1998, Mechanical vibration and shock—Mechanical mountingof accelerometersISO 8041:1990, Human response to vibration—MeasuringinstrumentationISO 10326-1:1992, Mechanical vibration—Laboratory method forevaluating vehicle seat vibration—Part 1: Basic requirementsISO 13090-1:1998, Mechanical vibration and shock—Guidance on safetyaspects of tests and experiments with people—Part 1: Exposure towhole-body mechanical vibration and repeated shock1) To be published. (Revision of ISO 5007:1990)

3 Terms and definitionsFor the purposes of this International Standard, the terms and definitionsgiven in ISO 2041 and the following apply.3.1 whole-body vibration vibration transmitted to the body as a wholethrough the buttocks of a seated operator3.2 operator seat that portion of the machine provided for the purposeof supporting the buttocks and back of the seated operator, including anysuspension system and other mechanisms provided (e.g., for adjustingthe seat position)3.3 frequency analysis process of arriving at a quantitative descriptionof vibration amplitude as a function of frequency3.4 measuring period time duration in which vibration data for analysisis obtained

4 Symbolsawi

( t ) frequency weighted acceleration in the direction i (i 5 x, y or z)awx rms value of the frequency weighted acceleration in the x directionawy rms value of the frequency weighted acceleration in the y directionawz rms value of the frequency weighted acceleration in the z directionBe resolution bandwidth of the frequency analysis, in hertzD distance from start, in metres (see clause 11)L ordinate of left-hand strip, in millimetres (see clause 11)rms root-mean-squareR ordinate of right-hand strip, in millimetres (see clause 11)Ts sampling time, in seconds

5 Vibration measurements5.1 Location of the measurements The vibration shall be measuredalong three mutually perpendicular axes, defined as follows:

x-direction: back to chesty-direction: right side to left sidez-direction: foot (or buttocks) to head

The vibration shall be determined as close as possible to the point orarea through which the vibration is transmitted to the body.a) In the case where the operator is normally sitting, transducersmounted in a semirigid disc shall be placed on the surface of the seatsuch that the transducers are located midway between the ischialtuberosities of the seated person. It is acceptable if the centre of the discis located slightly in front (up to 5 cm) of the ischial turberosities or thevertical projection of the Seat Index Point (SIP).b) In the case where the operator is normally standing, the transducersshall be located on the platform midway between the arches of the feet.5.2 Magnitude of vibration The quantity used to describe themagnitude of vibration shall be the frequency-weighted acceleration inmeters per second squared (m/s2), expressed as a root-mean-square(rms) value.

The frequency weightings to be used are defined in 6.3. The rms valueawi used in this International Standard is defined as the rms value of thefrequency weighted acceleration signal awi( t ) [i 5 x, y or z]:

awi5F 1

T0

TE awi2~ t !dt G 1/2

For tests on a standard track, the integration time shall be the timerequired to traverse the track.

6 Instrumentation6.1 GeneralMeasuring equipment may comprise:a) transducers (usually accelerometers);b) conditioning amplifiers and filters;c) telemetry set;d) recorders (digital or analog);e) meters.The dynamic range, sensitivity, accuracy, linearity and overload capacityof the vibration measuring system shall be in accordance with ISO8041:1990 for type 1 instruments.6.2 Transducers Accelerometers shall normally be used formeasurement of vibration. The mounting of accelerometers shall be inaccordance with ISO 5348 and the transducer manufacturer’sinstructions. Transducers oriented in different directions at a singlemeasurement location shall be as close together as possible. Careshould be taken to ensure, as far as is practical, that neither the mass ofthe measuring device and its fixture, nor any local resonances,significantly affect the measured value.The transducers used for the measurement in the seat shall be mountedin a semirigid disc (see Figure 1). The disc shall be 12 mm or less inthickness and be made of approximately 80-90 Shore-A molded rubberor plastic material.

NOTE For practical reasons it is usually not possible to perfectly alignthe accelerometers in the disc with the directions of the basicentriccoordinate system. In a tolerance range to within 615° of theappropriate directions, the accelerometers may be considered asaligned parallel to these directions.The transducers used for the measurement at the feet of a standingoperator shall be rigidly fixed (e.g. by screwing or glueing) on to theworking platform. If the working platform is covered by a resilientmaterial, the transducers may be mounted in the middle of a rigidmetal plate (about 30 cm 3 40 cm) with the operator standing onthe plate.

ASABE ÕISO 5008:2002 WÕCor. 1 „A2

6.3 Frequency weighting The frequency weightings to be used shallcorrespond to frequency weightings Wd (for the x and y directions) andWk (for the z direction) in accordance with ISO 2631-1:1997 for wholebody vibration.6.4 Calibration The whole measurement chain shall be checked bothbefore and after a sequence of measurements by using a calibrationsource that produces a known acceleration at a known frequency.

NOTE It is also important to regularly check that the whole chain isalso calibrated at other frequencies throughout the frequency range ofinterest.In addition to regular preventive calibration (e.g. every two years),calibration is also necessary after rough handling of any importantpart of the measurement chain. The results of the calibration checkshall be recorded.

7 Safety recommendationsSafety precautions shall be in accordance with ISO 13090-1.

8 OperatorIf the tractor fits one of the 3 tractor classes that are defined in ISO 5007and is equipped with a seat for which the SEAT factor has beenestablished for that class, the test can be made with one operatorweighing 75 kg 6 5 kg.If the tractor does not fit one of the 3 tractor classes that are defined inISO 5007 and/or the SEAT factor for the seat has not been established,the test shall be made with both a light and a heavy operator. The lightperson shall have a total mass of 52 kg to 55 kg, of which not more than5 kg may be carried in a belt around the waist. The heavy person shallhave a total mass of 98 kg to 103 kg, of which not more than 8 kg maybe carried in a belt around the waist.

9 Operator seat9.1 General The operator seat for the test shall be representative ofseries-produced models, with regard to construction, static and vibrationcharacteristics and other features that may affect the vibration test result.Any compliant end-stops or devices normally fitted to production versionsof the seat to be tested to minimize the effect of suspension over-travelshall be in place for the tests.9.2 Run-in Before the test, the suspension seats shall be run-in for aminimum of 1 h of operation under typical working conditions.9.3 Seat adjustment The seat shall be adjusted to the weight of the testperson in accordance with the manufacturer’s instructions.For seats with adjustable damping, the damper shall be set according tothe manufacturer’s instructions.For seats with fore-aft and/or lateral isolation, such isolation shall beworking.The other seat adjustments shall be made to suit the operator.

Key1 Cavity appropriate for accelerometers2 Thin metal disc for accelerometer mount and added centre rigidityFigure 1 – Design for semirigid disc for seat accelerometers

(see ISO 10326-1)

dopted by ASABE MAY 2006 … ASABE STANDARDS 2006

10 Condition of tractorThe tractor may be with or without a safety frame or cab, however, aROPS structure and the use of a seat belt are highly recommended. Fornormal measurements, the tractor shall be in working order with full fueltank and radiator, but without optional front and rear weights, tyre ballast,mounted implements and equipment and any specialized components.The tyres used in the test shall be the standard size for the tractor, asspecified by the manufacturer. The depth of the tread shall be not lessthan 65% of the depth of a new tread. The tyre walls shall not bedamaged and the tyre pressures shall be the arithmetic mean of theranges recommended by the manufacturer. The tyres shall be warmedup by traversing the test course at least 3 2 immediately prior to thestart of the test runs. Tyre pressures shall be measured before and aftera set of test runs and shall be within 65% of each other. The track widthadjustment shall be that which is usual for normal field work with thetractor on which the seat is fitted.When measurements are made under conditions different from thosespecified above, all differences shall be reported.

11 Measurement sites and operating conditions11.1 General Measurements shall be made on artificial test tracks or onactual work (field) sites (see annex A). The measurement sites andoperating conditions shall be appropriate for the machine under test.Where possible, the speed, load and any other relevant operatingconditions of the machine shall be kept constant throughout themeasurement period and shall be measured to an accuracy of 65%. Themeasurements shall be made when the ambient temperature is within therange from 5 °C to 30 °C.11.2 Artificial test track measurements11.2.1 Track description Vibration measurements shall be made whenthe tractor is driven over one or both of the following:a) a 35 m rougher track;b) a 100 m smoother track.Each track shall consist of two parallel strips suitably spaced for thewheel track of the tractor. The surface of each strip shall be either castin smoothly surfaced concrete or formed of pieces of wood, steel orconcrete sited firmly in a base framework. The surface of each track stripshall be defined by the ordinates of elevation, with respect to a levelbase, listed in Tables 1 and 2. For the rougher track (see Table 1), theelevation shall be defined at intervals of 80 mm along each strip; for thesmoother track (see Table 2), the elevation shall be defined at intervalsof 160 mm.

The strips shall be firmly sited on level ground and at each point alongtheir length shall have negligible variation across their width, which shallbe sufficient for the tractor wheels to be fully supported. Where the stripsare constructed of pieces of wood or steel or concrete, these shall be 60mm to 80 mm thick. They shall be spaced at 160 mm intervals for thesmoother track and at 80 mm intervals for the rougher track, but if it ismore convenient, 80 mm intervals may be used for the smoother track

ASABE ÕISO 5008:2002 WÕCor. 1 „AASABE STANDARDS 2006

(with linear interpolation of the data in Table 2 for the heights of theintermediate points).11.2.2 Operating speeds For the smoother track, the tractor shall beoperated at speeds of 10 km/h, 12 km/h and 14 km/h. For the roughertrack, the tractor shall be operated at speeds of 4 km/h, 5 km/h and 7km/h. The rms values of the weighted vibration along the three axes foreach test run shall be determined.

11.2.3 Reported values Measurements shall be made when the wholeof the tractor wheelbase is on or over the track surface.Five (5) runs shall be made at each speed for each weight of operator.For each run, the values for awx, awy, and awz shall be determined. Thereported vibration values shall then be the mean and standard deviationvalues for awx, awy, and awz for each axis at each of the three operatingspeeds as determined from the values measured at each of thosespeeds.

12 Test reportThe test report shall contain all the information necessary to understand,interpret and use the results arising from the application of thisInternational Standard.A specimen report is included in annex B to show the way in which thetest results shall be reported. As shown in this annex B, the test reportshall contain the following information:a) name and address of tractor or field machine manufacturer;b) type and model of tractor/machine;c) date of test;d) tractor/machine details:

1) mass (total, front and rear);2) cab or protective frame;3) tyres (manufacturer, type and size, pressure for both front and

rear);4) make and model of seat;5) tread width settings, front and rear;6) other details;

e) site details;1) type of surface;2) condition of surface;3) details of ground profile or power spectrum (if available);4) function of tractor/machine (if working);5) ambient temperature;

f) driver details;1) mass;

g) vibration measurements;1) speeds;2) sampling time at each speed;3) mean and standard deviation values of the weighted vibration at

each speed for each axis;h) name of the person responsible for the test;i) identification of test laboratory.

dopted by ASABE MAY 2006 … 3

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …4 ASABE STANDARDS 2006

Table 1 – Rougher track—Ordinates of elevation with respect to an arbitrary baseline

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …ASABE STANDARDS 2006 5

Table 1 – (continued)

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …6 ASABE STANDARDS 2006

Table 1 – (continued)

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …ASABE STANDARDS 2006 7

Table 2 – Smoother track—Ordinates of elevation with respect to an arbitrary baseline

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …8 ASABE STANDARDS 2006

Table 2 – (continued)

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …ASABE STANDARDS 2006 9

Table 2 – (continued)

Annex A(informative)

Field measurements

A.1 Application This annex provides a method for measuring thevibration exposure of the operator of an agricultural tractor or fieldmachine under non-standard test conditions.A.2 Variability Field measurements of operator vibration tend to bequite variable due to differences in the exact path followed, speedfluctuations, weather, temperature and the operator’s driving habits.When attempting to obtain data for comparative purposes, the bestresults are obtained if all of the data is acquired while attempting to holdthese variables as nearly constant as possible. That generally meansthat the data should be acquired on the same day under the sameweather conditions with the same operator.Also, more stable results are obtained if the data are acquired overrelatively long time periods (typically, 3 min or more).A.3 Field description The field conditions should be recorded in detail,including general condition of the site, soil characteristics, surface cover,surface ridges due to previous tillage operations and direction ofoperation with respect to those ridges, grades, etc. Where possible, theground profile and/or its power spectrum should also be recorded.A.4 Operating speeds Where appropriate for agricultural equipment,ground speed should be kept relatively constant throughout eachmeasuring period and the average ground speed during the periodreported. If the vibration test is being conducted during a work cycle thatinvolves several operating speeds and/or operating conditions, then a

ASABE ÕISO 5008:2002 WÕCor. 1 „A10

separate measuring period should be devoted to each such segment ofthe work cycle and the corresponding results so reported along with adescription of the work cycle involved. Where the speeds and/oroperating conditions are constantly varying during the work cycle, suchthat discrete separate cycle segments are extremely short in duration ornon-existent, the work cycle can be measured on a continuous basis.A.5 Integration time In all cases, the sampling time should be as longas is required to obtain vibration measurements representative of themachine and operating conditions. The minimum sampling time isdefined by:

2 3 Be 3 Ts . 140

Be , 0,5 Hz

If the vibration test is conducted during a work cycle that involves severaldiscrete separate segments, the minimum sampling time requirementshould be applied to each such segment. The minimum sampling timemay be obtained by combining like segments during either the actual testor the data analysis.A.6 Reported values Eight to ten (8 to 10) runs should be made at eachspeed of interest. For each run, the rms values of the weighted vibrationalong the three axes (awx, awy, and awz) should be determined. Thereported vibration values should then be the mean and standarddeviation values for awx, awy, and awz at each of the three operatingspeeds as determined from the values measured at each of thosespeeds.

dopted by ASABE MAY 2006 … ASABE STANDARDS 2006

ASABE ÕISO 5008:2002 WÕCor. 1 „Adopted by ASABE MAY 2006 …ASABE STANDARDS 2006 11

Annex B(informative)

Specimen report of measurement of whole body vibration of the operatorof an agricultural tractor or field machine