1、Designation: E 2300 09Standard Specification forHighway Traffic Monitoring Devices1This standard is issued under the fixed designation E 2300; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in p
2、arentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification describes the recommended proce-dure for identifying the performance and operating require-ments to be included in a purchase o
3、rder for Traffic MonitoringDevices. As such, the specification can be referenced by theuser and seller when determining compliance with each speci-fied requirement. It is the intent of this specification to have theuser require the seller to provide evidence that the brand andmodel of TMD offered by
4、 the seller has passed an applicableType-approval Test. If the TMD has not previously passed aType-approval Test, then it is the intent of this specification tohave the device type-approved before it is accepted by the user.If the TMD has previously passed a Type-approval Test, thenthis specificatio
5、n requires that the production version of thedevice provided by the seller pass an On-site Verification Testbefore being accepted by the user.1.2 Traffc Monitoring DeviceA Traffic Monitoring De-vice (TMD) is equipment that counts and classifies vehiclesand measures vehicle flow characteristics such
6、as vehiclespeed, lane occupancy, turning movements, intervehicle gaps,and other parameters typically used to portray traffic move-ment. TMDs usually contain a sensing element that convertsthe signal-generating phenomenon (such as, air pulse generatedby a vehicle tire passing over a pneumatic tube) i
7、nto anelectrical signal and electronics that amplify, filter, and other-wise condition the signal. Some TMDs provide outputs as relayor solid-state switch closures, while others contain signalprocessing that translates the signal into the required vehicleand vehicle flow data. TMDs whose outputs are
8、 relay or solidstate switch closures may be connected to roadside controllers,which process the switch-closure information and convert itinto vehicle flow data.1.3 Characterization of Traffc Monitoring DevicesThisspecification classifies Traffic Monitoring Devices by thefunctions they perform, the d
9、ata they provide, the requiredaccuracy of the data, and the conditions under which the deviceis expected to operate in conformity with the requirementsdeveloped through this specification.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mat
10、hematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and h
11、ealth practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 867 Terminology Relating to Vehicle-Pavement SystemsE 1318 Specification for Highway Weigh-In-Motion (WIM)Systems with User Requirements and Test MethodsE 2532 Test Me
12、thods for Evaluating Performance of High-way Traffic Monitoring Devices3. Terminology3.1 Definitions of terms and definitions of terms specific tothis specification are given below.3.2 Definitions:3.2.1 axle, naxis oriented transversely to the nominaldirection of vehicle motion, and extending the fu
13、ll width of thevehicle, about which the wheels at both ends rotate. (E 867,E 1318)3.2.2 axle count, nnumber of vehicle axles enumerated ata point on a lane or roadway during a specified time interval.(E 867)3.2.3 vehicle, none or more mobile units coupled togetherfor travel on a highway; a vehicle c
14、ontains one powered unitand may include one or more non-powered full-trailer orsemi-trailer units. (E 867)3.3 Definitions of Terms Specific to This Standard:3.3.1 accepted reference value, na particular quantity(number of vehicles in a particular class defined by number ofaxles and interaxle spacing
15、s, vehicle count, lane occupancy, orvehicle speed) that is agreed upon by the user and seller inadvance of testing of a TMD, which has an uncertaintyappropriate for the given purpose.1This specification is under the jurisdiction ofASTM Committee E17 on Vehicle- Pavement Systems and is the direct res
16、ponsibility of Subcommittee E17.52 onTraffic Monitoring.Current edition approved July 1, 2009. Published July 2009. Originally approvedin 2006. Last previous edition approved in 2006 as E 2300 06.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at
17、 serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.3.2 accuracy, ncloseness of agreement between a
18、valueindicated by a TMD and an accepted reference value.3.3.3 correct detection, nan indication by a TMD that avehicle actually passing over the detection area of the TMD isdetected by the TMD.33.3.4 data item, ncharacteristic associated with individualvehicles (count, class, and speed) or the conti
19、nuum of vehiclesat a location (density, flow rate, and queue length).3.3.5 detection area, nroad surface area above which asensor detects a vehicle or vehicle component.3.3.6 device identifier, ninformation output by a TMDthat includes, as a minimum, the model and serial number ofthe device.3.3.7 el
20、ectronics unit, ndevice that provides power to oneor more sensors, filters and amplifies the signals produced bythe sensors, and may perform other functions such as sensitiv-ity adjustment, failure indication, and delayed actuation oftraffic control signals.43.3.8 false detection, nan indication by
21、a TMD that avehicle not actually passing over the detection area of the TMDis detected by the TMD.33.3.9 flow rate, nnumber of vehicles passing a given pointor section of a lane or roadway during a designated timeinterval, usually 15 min, but expressed as an equivalent hourlyrate in vehicles/h.3.3.1
22、0 lane occupancy, npercent of selected time intervalthat vehicles are detected in the detection area of a sensor; thetime interval during which the lane occupancy is measured isusually 20 s to 30 s.53.3.11 missed detection, nan indication by a TMD that avehicle actually passing over the detection ar
23、ea of the TMD isnot detected by the TMD.33.3.12 sensor, ndevice for acquiring a signal that providesdata to indicate the presence or passage of a vehicle or of avehicle component over the detection area with respect to time(for example, flow rate or number of axles and their spacing),or one or more
24、distinctive features of the vehicle such as heightor mass.3.3.13 speed, nrate of vehicle motion expressed as dis-tance per unit of time.3.3.14 time stamp, nrecorded date and time at which ameasurement was made; information and format may betailored to the application, but usually consists of month,
25、day,year, hour, minute, second, and subsecond.3.3.15 tolerance, nallowable deviation of a value indi-cated by the device under test or a device in service from anaccepted reference value.3.3.16 traffc monitoring device, nequipment that countsand classifies vehicles and measures vehicle flow characte
26、ris-tics such as vehicle speed, lane occupancy, turning movements,and other items typically used to portray traffic movement.3.3.17 vehicle class by axle, ncharacterization of a ve-hicle by its number of axles and interaxle spacing.3.3.18 vehicle class by length, ncharacterization of ve-hicles by th
27、eir total length.3.3.19 vehicle count (volume), ntotal number of vehiclesobserved or predicted to pass a point on a lane or roadwayduring a specified time interval.3.3.20 vehicle passage, nsensor output pulse signal pro-duced when an initial vehicle detection is made in the detectionarea of the sens
28、or.3.3.21 vehicle presence, nsensor output signal producedthe entire time a vehicle is detected in the detection area of thesensor.4. Significance and Use4.1 The accuracy required of a TMD for data acquisitionand characterization of vehicles and traffic flow parameters isrelated to the traffic manag
29、ement or data reporting tasksupported by the device. The TMD to be procured shall bespecified by designating a Type from Table 1, a tolerance foreach data item required, and the conditions under which thedevice is expected to operate within the requirements devel-oped through this specification. For
30、 example, if a TrafficCounting device is desired to provide axle counts to within 65% tolerance, then specify a Type I-1, 5 % tolerance device. Ifa Speed Monitoring device is desired to provide the number ofvehicles correctly detected to within 65 % tolerance and speedto within 610 % tolerance, then
31、 specify a Type IV-1 devicewitha5%tolerance on the number of individual vehiclescorrectly detected and a 10 % tolerance on vehicle speedmeasurement. If a combination Speed Monitoring and TrafficSignal Control device is desired to provide the number ofvehicles correctly detected to within 65 % tolera
32、nce, speed towithin 610 % tolerance, vehicle presence to within 610 %tolerance, and lane occupancy to within 620 % tolerance, thenspecify a combination Type IV-1 device witha5%toleranceon the number of individual vehicles correctly detected and a10 % tolerance on vehicle speed measurement and Type V
33、I-1device with a 10 % vehicle presence tolerance and a 20 % laneoccupancy tolerance. The associated operating conditions shallbe specified by the user through consideration of requirementssuch as those shown in Table 2.5. Ordering Information5.1 TypeThe user shall specify a TMD by a type identifier(
34、that is, indicator of the vehicle characteristics detected by theTMD to support the function) as described in Table 1,atolerance for each required data item as described in 5.2, andthe conditions under which the device will be operated. Table1 also lists the detected vehicle characteristics (that is
35、, dataacquired by the TMD by which a vehicle or vehicle flowcondition is distinguished) and the data recorded per specified3The terms correct detection, false detection, and missed detection, rather thanthe aggregated vehicle count metric, are recommended as metrics for determiningthe ability of a T
36、MD to accurately detect vehicles. Aggregated measurements, suchas vehicle count over a time interval, can obscure the actual accuracy of a TMDsince failures to detect are often canceled by false detections. Therefore, evaluationmethods based upon aggregated metrics can provide misleading conclusions
37、concerning the ability of a TMD to correctly detect vehicles.4Klein, L.A., Gibson, D., and Mills, M.K., Traffc Detector Handbook: ThirdEdition , FHWA-HRT-06-108 (Vol. I) and FHWA-HRT-06-139 (Vol. II), U.S.Department of Transportation, Federal Highway Administration, Washington, DC,Oct. 2006. Also av
38、ailable at: http:/www.tfhrc.gov/its/pubs/06108/ and http:/www.tfhrc.gov/its/pubs/06139/5Different sensor models or technologies used to measure lane occupancy mayhave different detection area sizes and, hence, produce different occupancy values,although all devices are operating properly.E2300092tim
39、e interval for each type of TMD. In addition, the user shallspecify the recording of a device identifier and time stamp datawhen needed. The same data may support more than onefunction as shown by the entries in the last column of the table.The measurement units that typically correspond to TMD data
40、TABLE 1 Traffic Monitoring Device Functions, Types, Detected Vehicle Characteristics, and Data Recorded/Specified Time IntervalFunction Type Detected Vehicle Characteristic Data Recorded/Specified Time IntervalAITraffic Counting I-1 axle passage number of axlesI-2 vehicle passage number of vehiclesI
41、-3 vehicle presence number of vehiclesIITrafficCounting/ClassifyingII-1(classification by number of axlesand interaxle spacings)vehicle passage,number of axles,and interaxle spacingsduring vehicle passagenumber of axles,number of vehicles per class,vehicle speed,vehicle class by number of axlesand i
42、nteraxle spacingsII-2(classification by length)vehicle passageand speednumber of vehicles,vehicle speed,vehicle length and class,vehicle presence,lane occupancyIIIIncidentDetection DataIII-1 vehicle passage,presence, and speednumber of vehicles,vehicle speed,vehicle presence,or lane occupancyIVSpeed
43、 Monitoring IV-1 speed number of vehicles,vehicle speedVMetering Data(Ramp, Mainline, orFreeway-to-Freeway)V-1 vehicle presence number of vehicles,vehicle presence,or lane occupancyVISignal Control Data VI-1 vehicle presence number of vehicles,vehicle presence,or lane occupancyVIIEnforcement Aid VII
44、-1(speed)speed vehicle speedVII-2(red signal)location of front of vehicle,red signal indicationnumber of vehiclesand violationsVIII-3(dimension)vehicle locationand specified overall dimensionsvehicle presence,specified overall dimensionsAThe user shall specify the recording of device identifier and
45、time stamp data when needed.TABLE 2 Installation and operating Requirements for Potential Inclusion in TMD Purchase SpecificationsEnvironment Installationambient temperature weight and size limitationshumidity mounting or other installation constraintslighting power availabilitysun position and angl
46、e power surge and lightning resistanceprecipitation types (snow, rain, hail) input power interfaceother atmospheric obscurants (fog, dust) special cables and connectorsvibration and shockwind Setup and Calibrationoperating and calibration softwareVehicle Characteristics operating, installation, and
47、repair manualsvehicle class mixvehicle-to-vehicle gaps required to define vehicle flow rate andto evaluate TMD detection accuracyMiscellaneousfail safe operation if device failsOutput Data Items warrantydata recording interval software upgrades and product maintenancedata communication link other pe
48、rtinent items affecting installation, operation, maintenance,and storagedata interfacedata displayE2300093are listed in Table 3. Weigh-in-motion sensors and systems aretreated in Specification E 1318.5.2 ToleranceThe user shall specify a tolerance for eachrequired data item output by the TMD. A TMD
49、that records oroutputs multiple data items may have different tolerancesspecified for each data item as explained in Section 4.IftheTMD is a vehicle classifier, the tolerance may be specified bythe user to apply to the individual classes identified by thedevice or to the aggregate of all vehicle classes identified. Thetolerance should be specified by the user in a manner that isconsistent with the application supported by the TMD outputdata. Accordingly, the tolerance of the TMD may be specifiedin three ways, namely as percent differenc
