1、Designation: F 1572 08Standard Test Methods forTire Performance Testing on Snow and Ice Surfaces1This standard is issued under the fixed designation F 1572; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the evaluation of tire perfor-mance on snow and ice surfaces utilizing passenger car or lighttruck vehicles
3、. Since the tires are evaluated as part of atire/vehicle system, the conclusions reached may not be appli-cable to the same tires tested on a different vehicle.1.2 These test methods do not purport to identify everymaneuver useful for determining tire performance in a winterenvironment.1.3 These tes
4、t methods are not meant to evaluate vehicleperformance. Allowing for the variability of test results withdifferent vehicles, these procedures have been developed andselected to evaluate relative tire-snow performance.1.4 These test methods are suitable for research and devel-opment purposes, where t
5、ires are compared during a singleseries of tests. They may not be suitable for regulatory statutesor specification acceptance because the values obtained maynot necessarily agree or correlate either in rank order orabsolute traction performance level with those obtained underother environmental cond
6、itions on other surfaces or the samesurface after additional use.1.5 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It i
7、s theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 178 Practice for Dealing With Outlying ObservationsE 1136 Specification for A Ra
8、dial Standard Reference TestTireF 457 Test Method for Speed and Distance Calibration ofFifth Wheel Equipped With Either Analog or DigitalInstrumentationF 538 Terminology Relating to the Characteristics and Per-formance of TiresF811 Practice for Accelerometer Use in Vehicles for TireTestingF 1046 Gui
9、de for PreparingArtificially Worn Passenger andLight Truck Tires for TestingF 1650 Practice for Evaluating Tire Traction PerformanceData Under Varying Test ConditionsF 1805 Test Method for Single Wheel Driving Traction in aStraight Line on Snow- and Ice-Covered Surfaces2.2 SAE Standards:3SAE J1466 P
10、assenger Car and Light Truck Tire DynamicDriving Traction in Snow3. Terminology3.1 Definitions:3.1.1 candidate tire, na test tire that is part of a testprogram.3.1.1.1 DiscussionThe term “candidate object” may beused in the same sense as candidate tire. F 5383.1.2 candidate tire set, na set of candi
11、date tires. F 5383.1.3 control tire, na reference tire used in a specifiedmanner throughout a test program.3.1.3.1 DiscussionAcontrol tire may be of either type andtypical tire use is the reference (control) tire in Practice F 1650that provides algorithms for correcting (adjusting) test data forbias
12、 trend variations (See Practice F 1650 and Annex A1).F 5383.1.4 driving coeffcient (nd), nthe ratio of the drivingforce to a normal force. F 5383.1.5 driving force (F), nof a tire, the positive longitudi-nal force resulting from the application of driving torque.F 5383.1.6 grooming, vin tire testing
13、, mechanically reworkinga snow test surface in order to obtain a surface with moreconsistent properties. F 5383.1.7 ice, dry, nsmooth ice without loose surface materi-als. F 5383.1.8 longitudinal force (F), nof a tire, the component ofthe tire force vector in the X8 direction. F 5381These test metho
14、ds are under the jurisdiction ofASTM Committee F09 on Tiresand are the direct responsibility of Subcommittee F09.20 on Vehicular Testing.Current edition approved Oct. 1, 2008. Published December 2008. Originallyapproved in 1994. Last previous edition approved in 2005 as F 1572 99 (2005).2For referen
15、ced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from SAEAutomotive Headquarters, 755 W. Big Beaver, Suite 1600
16、,Troy, MI 48084.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.9 longitudinal slip velocity (L/T), nthe effective roll-ing radius multiplied by the difference between the spinvelocity (in rad/unit time) of a driven or braked tir
17、e and that ofa free rolling tire when each is traveling in a straight line.F 5383.1.10 reference tire, na special tire included in a testprogram; the test results for this tire have significance as a basevalue or internal benchmark. F 5383.1.11 snow, hard pack, nin tire testing, packed basewithout l
18、oose snow. F 5383.1.12 snow, medium hard pack, nin tire testing, packedbase with some loose snow.3.1.13 snow, medium pack, nin tire testing, groomedpacked base with 2.5 to 5.0 cm (1 to 2 in.) loose snow.F 5383.1.14 snow, soft pack, nin tire testing, freshly fallen ordeeply groomed base snow with 5.0
19、 to 7.5 cm (2 to 3 in.) loosesnow. F 5383.1.15 spin velocity, nthe angular velocity of the wheelabout its spin axis. F 5383.1.16 standard reference test tire (SRTT), na tire thatmeets the requirements of Specification E 1136, commonlyused as control tire or a surface monitoring tire.3.1.16.1 Discuss
20、ionThis is a Type 1 reference tire.F 5383.1.16.2 DiscussionA surface monitoring tire may also beused as a control tire.3.1.17 surface monitoring tire, na reference tire used toevaluate changes in a test surface over a selected time period.F 5383.1.18 test (or testing), na procedure performed on anob
21、ject (or set of nominally identical objects) using specifiedequipment that produces data unique to the object (or set).3.1.18.1 DiscussionTest data are used to evaluate ormodel selected properties or characteristics of the object (or setof objects). The scope of testing depends on the decisions to b
22、emade for any program, and sampling and replication plans (seedefinitions below) need to be specified for a complete programdescription. F 5383.1.19 test matrix, nin tire testing a group of candidatetires, usually with specified reference tires; all tests arenormally conducted in one testing program
23、.3.1.20 test tire, na tire used in a test. F 5383.1.21 test tire set, none or more test tires as required bythe test equipment or procedure, to perform a test, therebyproducing a single test result.3.1.21.1 DiscussionThe four nominally identical tires re-quired for vehicle stopping distance testing
24、constitute a test tireset. In the discussion below where the test tire is mentioned, itis assumed that the test tire set may be submitted for test tire,if a test tire set is required for the testing. F 5383.1.22 vertical load, nthe normal reaction of the tire onthe road which is equal to the negativ
25、e of normal force.F 5384. Summary of Test Method4.1 These test methods describe a series of vehicle maneu-vers which can be utilized by the tire and vehicle industry toconsistently measure the properties of a tires performance onsnow and ice surfaces in the braking, driving and corneringtraction mod
26、es.4.2 These test methods outline the procedures for conduct-ing the following tests:4.2.1 Road circuit handling,4.2.2 Winter hill climb,4.2.3 Winter slalom,4.2.4 Accelerationstraight ahead,4.2.5 Brakingstraight ahead, and4.2.6 Step steer.5. Significance and Use5.1 These test methods describe techni
27、ques for assessing theperformance characteristics of tires in a winter environment onsnow and ice surfaces in a standardized manner. When onlysnow is referred to hereafter, it should be understood that ice isimplied as appropriate.5.2 A series of maneuvers are conducted to characterizeseveral aspect
28、s of the tire performance in snow, since a singlemaneuver is not sufficient to characterize all aspects of a tiresperformance.6. Interferences6.1 Factors which may affect tire snow performance andmust be considered in the final analysis of data include:6.1.1 Snow/ambient temperature,6.1.2 Mechanical
29、 breakdown of snowflake into granularcrystals,6.1.3 Solar heat load and tire temperature,6.1.4 Tire wear condition or preparation,6.1.5 Tire pressure and vertical load,6.1.6 Test vehicle characteristics,6.1.7 Snow surface characteristics,6.1.8 Test driver, and6.1.9 Rim selection.7. Apparatus7.1 Due
30、to the nature of these test methods, specific require-ments for apparatus will be limited. A general discussion oftypes of apparatus and their uses follows.7.1.1 Time MeasurementThis provides one of the simplestand lowest cost methods of quantifying tire performance.However, since time measurement i
31、nherently involves averag-ing over a time period, the measurements obtained provideonly a general overview of performance.7.1.1.1 Time measurement apparatus may be onboard thevehicle or stationary and may vary from handheld stopwatchesto optical start/stop gates or combined apparatus for measure-men
32、t of time and other properties (for example, fifth wheelapparatus).7.1.1.2 Many tests measure time to complete a slalom orhill-and-curve course. Other tests involve measuring the timenecessary to reach some condition, such as the time necessaryto stop from a given speed or the time to achieve a cert
33、ainspeed from rest.7.1.2 Speed and Distance MeasurementVehicle speed anddistance measurement may be used for evaluating tire snowF1572082performance. There are a number of technologies for measur-ing speed and distance.7.1.2.1 Fifth Wheel BasedThis test method requires that alightly loaded free-roll
34、ing wheel be attached to the vehicle. Arevolution counting device on this wheel is used to providetypical distance resolutions of 1 cm (0.4 in.). Fifth wheel typedevices are highly reliable but may slip on low friction surfacesor bounce on a rough surface, providing inaccurate readings. Afifth wheel
35、 may not be appropriate on a road circuit handlingcourse. Fifth wheel type devices are not suitable for use inradical maneuvers or situations where the vehicle may slide orspinout, as these maneuvers may cause damage to the devices.See Test Method F 457 for additional information on fifthwheels.7.1.
36、2.2 Non-Contact OpticalOptical sensors are availablewhich can measure both longitudinal and lateral speed. Sincethese sensors do not contact the road surface they may be usedwithout damage in tests which may involve spinouts orsignificant lateral motion. However, optical sensors depend onsurface mic
37、rotexture and they may not work on all surfaceconditions.7.1.2.3 Wheel SpeedA wheel speed sensing device (opti-cal encoder or tachometer) mounted on the wheels of the testvehicle permits the measurement of rotational speed of thewheels and the calculation of distance traveled. These testmethods may
38、be prone to error due to wheel slip or changingrolling radius. Wheel speed sensors are usually used inconjunction with 7.1.2.1 or 7.1.2.2 to determine the extent ofwheel spin.7.1.2.4 AccelerometersSeveral commercial performancecomputers exist which calculate speed and distance traveledbased on inter
39、nally mounted accelerometers.4These devicesperform numerical integration to compute speed and distancefrom the acceleration signal. Accelerometer-based devices arenon-contact and self-contained; they are easy to transferbetween vehicles. These devices are best suited to tests whichinvolve primarily
40、straight ahead motion and which involveevents of short duration.7.1.2.5 RadarSelf-contained radio and microwave speedsensing devices are not widely used for tire performancetesting. Development of these devices is continuing.7.1.2.6 TelemetryVehicle position sensing equipment isavailable which utili
41、zes both stationary and vehicle mountedtransceivers. Using multiple stationary antennae, this equip-ment may provide dynamic vehicle position, speed and orien-tation data with great accuracy. The disadvantages to thisapproach are the cost of the systems and the difficulty inmoving the system to a di
42、fferent test site. Telemetry is notwidely used at present but may be of value in the future.7.1.3 Acceleration MeasurementAcceleration measure-ment is a primary technology used for evaluating tire snowperformance. Due to their low cost and ease of mounting,three-axis accelerometers provide a simple
43、way to evaluatesome aspects of tire performance.7.1.3.1 Accelerometers function by measuring the accelera-tion of a vehicle. This acceleration depends on the forcesexisting at the tire/surface interface.7.1.3.2 Accelerometers typically have bandwidths in excessof 100 Hz, allowing dynamic measurement
44、 of forces in ahandling test.7.1.3.3 Drawbacks to the use of accelerometers include:sensitivity to wind and vehicle orientation changes, such asbody pitch and roll, which occur in handling maneuvers(gyro-stabilized platforms can be used to eliminate this prob-lem); the need to mount the acceleromete
45、r at or near the centerof gravity of the test vehicle to obtain accurate data; the factthat accelerations on snow and ice surfaces are typically smallin magnitude; and the fact that accelerometer signals aretypically noisy, leading to the need for filtration of the signal.See Practice F811for additi
46、onal accelerometer usage informa-tion.7.1.4 Vehicle OrientationDevices to measure vehicle ori-entation include gyroscopes, wheel steer angle transducers andsome telemetry systems.7.1.4.1 Measurement of the test vehicles orientation aboutits pitch and roll axis is typically used for correction ofacce
47、lerometer based test systems.7.1.4.2 Measurement of the test vehicles orientation aboutits yaw axis as well as wheel steer angle measurement are usedin cornering performance testing.7.1.4.3 Due to high cost, vehicle orientation measurementdevices are typically used only on tests requiring a high deg
48、reeof accuracy.7.1.5 ForceDirect measurement of tire/surface forces isnormally accomplished using load cells.7.1.5.1 Load cells provide the most accurate measure of tireforces under dynamic conditions.7.1.5.2 Using specially designed suspensions, load cellbased systems may be built which are not sig
49、nificantly affectedby body roll of the test vehicle.7.1.5.3 Due to mounting requirements, load cell-based sys-tems typically are not easily transferred between multiplevehicles.8. Selection and Preparation of Test Tires8.1 Ensure that all test tires are approximately the same ageand stored essentially at the same conditions prior to testingunless otherwise specified.8.2 Test tires shall be mounted on Tire and Rim Association(TRA)5or applicable document,6,7recommended rims byusing conventional mounting methods. Proper bead seatingshall be
