Transport Monitoring Team, Imperial Gate Business Park, Corinium Avenue, Gloucester, GL4 3BW www.gloucestershire.gov.uk
Email: [email protected] Tel: 08000 514514
Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 1 of 21 Author: PS Checker: DJ Date: April 2011
TRIAL OF AUTOMATIC TRAFFIC COUNTING (ATC) EQUIPMENT FOR TEMPORARY SURVEYS
March 2011
Comparison of all types of Radar ATC available commercially in the UK Comparison of all types of Pneumatic Tube ATC Event recorders available
commercially in the UK
Volume accuracy
Speed accuracy
Length / classification accuracy
Usability
Release notes:
Issue 1 21/03/2011 Draft for circulation amongst trial participants.
Issue 2 23/03/2011 First full release. Includes participant comments in Appendix 1
Issue 3 04/04/2011 Includes corrected analysis of Golden River M500 speed accuracy and re-analysed per-vehicle analysis for all radar units except Applied Traffic SR4, to ensure consistency.
Transport Monitoring Team, Imperial Gate Business Park, Corinium Avenue, Gloucester, GL4 3BW www.gloucestershire.gov.uk
Email: [email protected] Tel: 08000 514514
Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 2 of 21 Author: PS Checker: DJ Date: April 2011
SUMMARY OF RESULTS:
SUMMARY OF CONCLUSIONS:
Gloucestershire Highways Transport Monitoring Team will be purchasing CA Traffic Radar Recorders
Gloucestershire Highways is happy to endorse the use of the following equipment:
o Applied Traffic SR4 o CA Traffic Radar Recorder and EVR o Golden River M500 o Traffic Technology SDR Pro o Metrocount 5600
Until improvements to accuracy are made, Gloucestershire Highways recommends that ViaCount II radar units should only be used for monitoring 1 lane of traffic.
Until improvements to classification accuracy are made and evidence of speed accuracy provided, Gloucestershire Highways recommends that Golden River M420 tube units should only be used for monitoring traffic volumes.
Transport Monitoring Team, Imperial Gate Business Park, Corinium Avenue, Gloucester, GL4 3BW www.gloucestershire.gov.uk
Email: [email protected] Tel: 08000 514514
Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 3 of 21 Author: PS Checker: DJ Date: April 2011
TABLE OF CONTENTS
Section Page
1 Background to the trial 4 2 Trial Methodology 6 2.1 Control data 6 2.2 Site selection 6 2.3 Equipment installation & configuration 7 2.4 Data analysis 9 2.5 Scoring system 12 3 Results 14 3.1 Radar ATC units – results of per-vehicle analysis 14 3.2 Tube ATC units – results of per-vehicle analysis 14 3.3 Results summary – accuracy 15 3.4 Results summary – usability 16 3.5 Results summary – overall 17 4 Conclusions 18 Appendix 1 – Comments arising from Issue 1 of report 19 Appendix 2 – Contact details for participating suppliers 21
Appendix 3 – Tabulated analysis Separate document
Appendix 4 – Per vehicle record analysis Separate document
Transport Monitoring Team, Imperial Gate Business Park, Corinium Avenue, Gloucester, GL4 3BW www.gloucestershire.gov.uk
Email: [email protected] Tel: 08000 514514
Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 4 of 21 Author: PS Checker: DJ Date: April 2011
1. Background to the Trial
1.1. Gloucestershire Highways Transport Monitoring Team carries out numerous temporary Automatic
Traffic Count (ATC) surveys each year.
1.2. Surveys are carried out using equipment with either pneumatic tube sensors or radar detectors.
1.3. The purpose of the majority of these surveys is to establish traffic flow volumes, patterns and vehicular speeds over a period of at least 7 days.
1.3.1. Both pneumatic tube and radar ATCs provide volume and speed data which is generally
considered to be within acceptable accuracy tolerances (providing installation and set-up follows the manufacturer’s guidelines).
1.4. In a minority of surveys, vehicle classification (distinguishing between vehicle types) data is also
required.
1.4.1. Pneumatic tube ATCs provide detailed vehicle classification data based on axle spacings. Various classification schemes are available, with up to 15 types of vehicle being differentiated. The principal limitation of these schemes is an inability to differentiate between 2-axled vans/lorries which are under/over 7.5 tonnes maximum gross weight – the definition of a Heavy Goods Vehicle (HGV).
1.4.2. Radar ATCs provide vehicle length data, which can be aggregated to give an estimate of
light, medium and heavy vehicles. Limitations of this system of vehicle classification include light vehicles with trailers being recorded as medium or heavy; and difficulties in distinguishing between buses and HGVs.
1.5. Both pneumatic tube and radar ATCs are prone to a reduction in data quality if used to monitor
more than 1 traffic lane. If 2 or more vehicles pass through the detection zone simultaneously, mis-classification and/or mis-counting can be caused.
1.5.1. In recent years, it has been accepted (in Gloucestershire at least) that a 2-lane single
carriageway road with a daily flow of up to 10,000 vehicles can be monitored by a single tube or radar ATC unit with levels of vehicle coincidence remaining acceptable.
1.6. Due to the operational efficiencies available, Gloucestershire Highways is looking to use radar ATCs
to carry out the majority of temporary surveys where classification data is not specifically requested.
1.6.1. Operative safety requirements dictate that installing or removing pneumatic tube sensors
across a carriageway requires 2 technicians on site and consideration of the use of additional Traffic Management on high speed (50 or 60mph limit) roads. Additional Traffic Management for tube installations currently costs Gloucestershire Highways between £300 and £500 per day.
1.6.2. ATC radar units can be installed by a single technician, without any in-carriageway work or
requirement for Traffic Management. Use of a ladder is required in some circumstances, although it is rare for units to be mounted higher than 3m from the ground, so “working at height” issues are quite easily and cheaply addressed.
1.7. Before investing in further radar ATCs, some evaluation of the available models is necessary to
satisfy procurement procedures. Gloucestershire Highways is not aware of any recent evaluations having been carried out including all of the currently available models.
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1.8. In the course of setting up the trial, it became apparent that there was also interest in testing
“event” recording pneumatic tube ATCs. 1.8.1. “Event” recorders do not store vehicle records at the roadside, but record the details of
each individual sensor activation, which is converted into vehicle records post-survey by analysis software.
1.8.2. Again, there does not appear to have been an independent evaluation including all of the
current models. 1.8.3. As Gloucestershire Highways currently uses 1 type of event recorder and handles survey
data collected using another, it made sense to extend the scope of the trial to include this type of equipment.
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Email: [email protected] Tel: 08000 514514
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2. Trial methodology
2.1. Control data
2.1.1. It is proposed to use 2 types of control data: a permanent ATC site with inductive loop sensors and video footage.
2.1.1.1. Traffic volume and speed data from a correctly installed and configured loop ATC
site is considered to be the optimum standard for traffic surveys. Loop ATC data does not suffer from vehicle coincidence in the detection zone.
2.1.1.2. It is important that loop ATC data used should include per-vehicle records, to allow
direct comparison of how each vehicle is recorded by the different equipment.
2.1.1.3. Classification of vehicles by a loop ATC is based on the magnetic profile of the vehicle’s metallic chassis. The class schemes used are therefore slightly different to those based on axles, used by tube ATCs.
2.1.1.4. Vehicle length is recorded by loop ATCs, but this again is based on the length of the
metallic chassis, so tends to slightly under-record (plastic/rubber bumpers are missed).
2.1.1.5. Video footage of the trial site during the survey, coupled with length markings painted on the carriageway can be used to verify actual vehicle types and lengths.
2.1.1.6. Comparison of individual vehicle records obtained from the loop ATC, the
radar/tube ATC and the video footage will enable the number of vehicles missed and the number of spurious records created by the radar/tube ATCs to be quantified.
2.2. Site selection
2.2.1. The trial site should have a reliable loop ATC site recording per-vehicle data. 2.2.2. The trial site should have plenty of street furniture near the loop ATC site to allow for
securing/mounting the radar/tube ATC equipment.
2.2.3. The trial site should be on a relatively straight section of road to give the best approach angle for traffic.
2.2.4. Vehicle speeds through the length of the trial site should be consistent.
2.2.5. It was decided that the trial site should be on a single carriageway, 2-lane, bi-directional
road with a daily traffic flow of below 10,000 vehicles. This is in order to quantify the impact of vehicle coincidence in the detection zone and determine whether the current assumptions about using a single recorder for 2 lanes of traffic are still valid.
2.2.6. ATC site 4123 – Innsworth Lane, Gloucester was chosen as the trial site, subject to the
approval of participating suppliers.
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Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 7 of 21 Author: PS Checker: DJ Date: April 2011
Figure 1 – location of ATC site 4123
2.2.7. All participating suppliers accepted the trial site as being suitable. 2.2.8. Site 4123 is equipped with an EMU loop profiling vehicle classifier, supplied and
commissioned by the manufacturer TDC Systems. This is an advantage, given that TDC Systems are not otherwise involved in the trial and the data from their equipment can be considered truly independent.
2.3. Equipment installation and configuration
2.3.1. All participating suppliers were given the opportunity to install, configure and remove their equipment themselves or have an approved installer undertake the work for them. The purpose of this was to ensure the best possible data quality by following recommended installation and configuration procedures.
2.3.2. All suppliers carried out their own installation, with the exception of CA Traffic who
supervised the installation of pneumatic tubes by Gloucestershire Highways. All suppliers configured their own equipment.
2.3.3. Suppliers were able to choose their own mounting point / installation location and given the
option of using an alternative trial site if they were not satisfied. All suppliers declared themselves satisfied with the locations available.
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Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 8 of 21 Author: PS Checker: DJ Date: April 2011
Figure 2 – equipment installation location plan
Figure 3 – ATC site 4123 with carriageway markings, radar ATCs and video surveillance
ATC 4123
Video surveillance
Radar ATCs
Loop sensors & length markings
Transport Monitoring Team, Imperial Gate Business Park, Corinium Avenue, Gloucester, GL4 3BW www.gloucestershire.gov.uk
Email: [email protected] Tel: 08000 514514
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2.3.4. Equipment was required to record both traffic lanes continuously for a period of at least 7
days. 2.3.5. Equipment was installed between 31
st January and 17
th February 2011 and removed between
11th
February and 18th
March 2011. 2.3.6. The loop ATC site was recording continuously throughout the trial period. 2.3.7. A 2-hour period of video footage was to be recorded to allow detailed analysis of individual
vehicle records. As it was not possible to arrange for all equipment to be on site simultaneously, 2 batches of video footage were recorded: 1100-1300hrs on 10
th February and
1200-1400hrs on 18th
February. 2.3.8. Length markings were painted on the carriageway in both lanes at 50cm intervals.
2.4. Data Analysis
2.4.1. Gloucestershire Highways uses the C2 software suite for traffic data analysis, provided and hosted by Drakewell. One advantage of this system is that it is manufacturer independent and allows processing and storage of, and reporting on almost all types of raw traffic data files.
2.4.2. Raw data files from the radar and tube ATC units were provided to Gloucestershire
Highways by the participating suppliers. These were all successfully processed using C2, with the exception of the Golden River M420 data file. Processed results for this unit were provided by Golden River in Excel format.
2.4.3. The control data from the loop ATC site is stored using the Euro 6 class scheme:
2.4.3.1. Motorcycles 2.4.3.2. Car / Van 2.4.3.3. Car / Van & trailer 2.4.3.4. Rigid Goods 2.4.3.5. Articulated HGV 2.4.3.6. Bus / Coach
2.4.4. The event data from the tube recorders was processed to produce class data in the Euro 13 class scheme:
2.4.4.1. Car / LGV with or without 1 or 2 axle trailer 2.4.4.2. 2 axle rigid HGV 2.4.4.3. 3 axle rigid HGV 2.4.4.4. 4 axle rigid HGV 2.4.4.5. 2 axle rigid HGV & trailer 2.4.4.6. 3 axle rigid HGV & trailer 2.4.4.7. 3 axle articulated HGV 2.4.4.8. 4 axle articulated HGV (2 axle tractor) 2.4.4.9. 5 axle articulated HGV (2 axle tractor) 2.4.4.10. 4/5 axle articulated HGV (3 axle tractor) 2.4.4.11. 6 axle articulated HGV 2.4.4.12. 2/3 axle bus / coach 2.4.4.13. >7 axle vehicles and unclassified vehicles
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2.4.5. Other than formatting raw data files where necessary for loading into the C2 database,
Gloucestershire Highways has not manipulated the trial data in any way. No records have been added, deleted or amended. Raw data files have been retained in their original state to allow for auditing of this fact.
2.4.6. The video footage was analysed by Gloucestershire Highways staff. All vehicles were
classified according to time, direction of travel, vehicle length and type. Total vehicle length was estimated by using the markings painted on the carriageway. For HGVs, PSVs and any other vehicles with more than 2 axles, the distance between axles was also measured, to assist with verifying tube classification accuracy. The vehicle type classifications used were designed to allow comparison with both loop and tube class schemes:
2.4.6.1. Pedal cycles 2.4.6.2. Motorcycles 2.4.6.3. Light Goods Vehicles (LGV) (<3.5 tonnes Max Gross Weight) 2.4.6.4. Medium Goods Vehicles (MGV) (3.5-7.5t MGW) 2.4.6.5. 2 axle rigid HGV 2.4.6.6. 3 axle rigid HGV 2.4.6.7. 4 axle rigid HGV 2.4.6.8. 3 axle articulated HGV 2.4.6.9. 4 axle articulated HGV 2.4.6.10. 5 axle articulated HGV 2.4.6.11. 6 axle articulated HGV 2.4.6.12. Passenger Service Vehicle (PSV)
Figure 4 – screenshot from video footage, showing loop ATC, CA Traffic tubes and carriageway markings
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2.4.7. Volume Accuracy Check
2.4.7.1. 7-day directional volumetric reports with data displayed in 15 minute time intervals
were prepared for each radar and tube ATC and compared with identical reports from the loop ATC. The difference between the 2 was calculated numerically and as a percentage of the total flow.
2.4.8. Speed Accuracy Check
2.4.8.1. 7-day directional average speed reports with data displayed in 15 minute time intervals were prepared for each radar and tube ATC and compared with identical reports from the loop ATC. The difference between the 2 was calculated numerically and as a percentage of the total flow.
2.4.9. Video Volume & Length Accuracy Check
2.4.9.1. A length bin report with data displayed in 15 minute intervals was produced for each radar ATC for the complete 7 day period. The length bins used were:
2.4.9.1.1. <5.2m – likely to include pedal cycles, motorcycles, cars and LGVs 2.4.9.1.2. 5.2-6.5m – likely to include larger LGVs, MGVs and minibuses 2.4.9.1.3. 6.5-11m – likely to include MGVs, rigid HGVs and buses 2.4.9.1.4. >11m – likely to include articulated HGVs
2.4.9.2. The report also displayed the mean vehicle length calculated from individual vehicle records. These reports were compared with identical reports from the loop ATC. The difference between the 2 was calculated numerically and as a percentage of the total flow. This report was not used in the calculation of accuracy, but was done for completeness and to check for consistent performance of the equipment during the 2-hour period used for per-vehicle analysis.
2.4.9.3. A per-vehicle report was produced for each radar ATC for the 2-hour period covered
by video surveillance. The report showed the time, direction, speed and length for each vehicle detected. This was them compared with an identical per-vehicle report from the loop ATC and the per-vehicle analysis from the video footage. The 3 sets of records were then synchronised to allow for marginal differences in the recorder clock settings. Checks were made to establish the number of vehicles missed by the radar ATC, the number of spurious readings recorded by the radar ATC and how close the radar ATC length readings were to the loop readings and the manual estimates from the video footage.
2.4.10. Video Volume & Class Accuracy Check
2.4.10.1. A class report with data displayed in 15 minute intervals was produced for each tube
ATC for the complete 7 day period. These reports were compared with identical reports from the loop ATC. The classes were aggregated to allow direct comparison between Euro 6 and Euro 13 class schemes. The difference between the 2 was calculated numerically and as a percentage of the total flow. This report was not used in the calculation of accuracy, but was done for completeness and to check for consistent performance of the equipment during the 2-hour period used for per-vehicle analysis.
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2.4.10.2. A per-vehicle report was produced for each tube ATC for the 2-hour period covered
by video surveillance. The report showed the time, direction, speed, estimated length if available and class of each vehicle detected. This was them compared with an identical per-vehicle report from the loop ATC and the per-vehicle analysis from the video footage. The 3 sets of records were synchronised to allow for marginal differences in the recorder clock settings. Checks were made to establish the number of vehicles missed by the radar ATC, the number of spurious reading recorded by the radar ATC and the number of vehicles mis-classified by the tube ATC.
2.4.10.3. Each of the tube ATC suppliers was asked for a copy of the detailed class tables used
to determine the classification of each vehicle. Typically for an axle-based class scheme, this would define the number of axles detected and the range of possible distances between axles for each class “bin”.
2.4.10.3.1. Metrocount supplied this information for their version of the Euro 13
scheme. CA Traffic did not supply any information. Golden River did not supply any information over and above the Vehicle Classification Table which appears on page 66 of the Count and Classify Manual Issue 1.0 which Gloucestershire Highways already held.
2.4.10.3.2. The purpose of requesting this information was to allow differentiation
between inaccuracies in the Euro 13 class scheme definitions themselves and inaccuracies in the tube ATC equipment.
2.4.10.3.3. Where equipment was found to have correctly classified a vehicle according
to its class scheme tables – even though the vehicle was mis-classified according to its actual type, the equipment was deemed to have operated correctly.
2.4.10.3.4. It is hoped that future analysis of the per-vehicle records from this study
might be helpful in improving the currently accepted definitions of the Euro 13 class scheme.
2.5. Scoring system
2.5.1. Accuracy
2.5.1.1. The accuracy score for each radar ATC unit was to be determined as the average of:
2.5.1.1.1. % accuracy for average volume for near side lane 2.5.1.1.2. % accuracy for average volume for far side lane 2.5.1.1.3. % accuracy for average speed for near side lane 2.5.1.1.4. % accuracy for average speed for far side lane 2.5.1.1.5. % accuracy for detailed count & length (video) analysis for near side lane 2.5.1.1.6. % accuracy for detailed count & length (video) analysis for far side lane
2.5.1.2. Radar ATC units were ranked 1-5 based on their accuracy scores.
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Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 13 of 21 Author: PS Checker: DJ Date: April 2011
2.5.1.3. The accuracy score for each tube ATC unit was to be determined as the average of:
2.5.1.3.1. % accuracy for average volume for near side lane 2.5.1.3.2. % accuracy for average volume for far side lane 2.5.1.3.3. % accuracy for average speed for near side lane 2.5.1.3.4. % accuracy for average speed for far side lane 2.5.1.3.5. % accuracy for detailed count & class (video) analysis for near side lane 2.5.1.3.6. % accuracy for detailed count & class (video) analysis for far side lane
2.5.1.4. Tube ATC units were ranked 1-3 based on their accuracy scores.
2.5.1.5. Accuracy rankings were given a 60% weighting in calculating the overall scores.
2.5.2. Usability
2.5.2.1. All radar ATCs were scored 1-5 and all tube ATCs were scored 1-3 against the
following criteria:
2.5.2.1.1. Ease of installation 2.5.2.1.2. Ease of configuration 2.5.2.1.3. Endurance (battery performance & memory capacity) 2.5.2.1.4. Choice & suitability of communications / download methods 2.5.2.1.5. Capability / flexibility of data analysis software and ease of use 2.5.2.1.6. Purchase price 2.5.2.1.7. Anticipated maintenance costs (battery replacement frequency & cost,
standard service charge) 2.5.2.1.8. Experience of post-sales support
2.5.2.2. Where information was not available or it was not appropriate to allocate a score,
the category was left blank, so as not to affect the average.
2.5.2.3. These scores will inevitably be slightly subjective and particular to Gloucestershire Highways. Other persons using this report to inform their own decisions may wish to disregard or adjust them.
2.5.2.4. Usability rankings were calculated based on the average of these scores.
2.5.2.5. Usability rankings were given a 40% weighting in calculating the overall scores.
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3. Results
3.1. Radar ATC units – results of per-vehicle analysis
Figure 5 – results of per-vehicle analysis for radar units
3.2. Tube ATC units – results of per-vehicle analysis
Figure 6 – results of per-vehicle analysis for tube units
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3.3. Results Summary – Accuracy
Figure 7 – summary of accuracy results (all units)
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3.4. Results Summary – Usability
Figure 8 – summary of usability results (all units)
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3.5. Results Summary – Overall
Figure 9 – overall results
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4. Conclusions
4.1. Both radar and tube ATC units are capable of recording very accurate volume, speed and length/class data from a single traffic lane.
4.2. If data quality is the prime consideration in setting up a survey, one ATC unit should be used per
traffic lane.
4.3. Gloucestershire Highways is satisfied that the following units are capable of collecting volume, speed and length/class data bi-directionally on a single carriageway road with flows of 7,000 vehicles per day to a level of accuracy acceptable for the majority of its surveys:
4.3.1. Applied Traffic SR4 4.3.2. CA Traffic Radar Recorder and EVR 4.3.3. Golden River M500 4.3.4. Traffic Technology SDR Pro 4.3.5. Metrocount 5600
4.4. It seems reasonable to conclude that previous assumptions were correct and that 1 radar or tube ATC can cover 2 lanes of bi-directional traffic up to about 10,000 vehicles per day without significant loss of data quality in the far traffic lane.
4.5. Gloucestershire Highways would be happy to use any of the equipment listed in 4.3 above. Use of
these types of equipment by contractors working on behalf of Gloucestershire Highways will also be accepted.
4.6. It is recommended that Gloucestershire County Council makes this list of equipment available to
developers commissioning surveys for use in planning applications.
4.7. The results of this trial will be shared with all participating suppliers, Atkins (Gloucestershire County Council’s partner in Gloucestershire Highways) and other local authorities.
4.8. Results will be made available to other interested commercial parties only with the agreement of
participating suppliers.
4.9. Given a significant price difference between the radar ATCs ranked joint 1st
overall, Gloucestershire Highways has chosen to purchase from CA Traffic.
4.10. Gloucestershire Highways would encourage all participants to use the detailed analysis
carried out in this trial to refine firmware/software to further improve accuracy.
4.11. It is hoped that ViaCount and Golden River M420 equipment can be re-tested when improvements have been made to their systems.
4.11.1. Until such time, Gloucestershire Highways would only recommend:
4.11.1.1. ViaCount II equipment be used for volume and speed surveys on 1 lane of traffic only.
4.11.1.2. Golden River M420 equipment be used for volume surveys on 1 or 2 lanes of traffic
only.
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Appendix 1
Comments arising from Issue 1 of report
Security of radar ATC installations o Applied Traffic have pointed out that they consider their mounting bracket to be more
resistant to vandalism once installed than alternatives based on banding. They suggest this compensates for the small amount of additional time which may be required to install the system.
Improvements to radar ATC usability o Traffic Technology advise that “Generation 3” of the SDR Pro is due for imminent release
and that any future purchases are likely to be for this unit (which was not available for use in the trial). The new versions will have the following features to improve “usability”:
Built-in wireless BluetoothTM
communications Retained compatibility with Bluetooth
TM equipped Palm equipment
New “Datacollector” device for use as an alternative to Palm for set-up and data retrieval
Improved data compression and 2-3 times faster communication and data retrieval
Selection of tube ATC classification scheme o CA Traffic advise that the FHWA class scheme available for analysis of EVR data is more
relevant to UK traffic than the Euro 13 scheme used. CA state that analysing the same raw data file using the FHWA scheme would have approximately halved the number of classification errors observed in the EVR data.
Comparison of speed data accuracy o CA Traffic have expressed concern that analysing speeds based on reports rounded to the
nearest whole mph introduces a small potential for error in the results.
Difference in trial dates o Some concern has been expressed that as not all equipment was running simultaneously on
site, some units would have recorded more traffic than others in the course of the analysed 7-day period.
o Gloucestershire Highways agrees that to be completely fair, proportional allowance should be made for increased discrepancies in data quality (especially on the far side of the carriageway).
o It is felt however, that as all days in the trial period had total flows of well below 10,000 vehicles, accuracy levels achieved in these circumstances are still pertinent to the aims of the trial. For the time being, the additional work in calculating and applying such allowances does not seem to be merited. We would however be happy to assist others in undertaking this exercise if they wish.
Usability “Endurance” scoring o There was some ambiguity in the scoring of counter endurance in Issue 1 of this report.
Essentially all units have sufficient memory capacity to record more data than Gloucestershire Highways is likely to collect in the course of a normal survey. Greater weighting was therefore given to the battery endurance.
o In this issue, separate scores have been given for both memory capacity and battery endurance, to give greater clarity.
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Usability “Capability / flexibility of data analysis software” scoring o Analysis of Metrocount trial data was carried out in Drakewell’s C2 software using per-
vehicle records generated from the raw data by Metrocount’s Traffic Executive software. o Metrocount would like to clarify that although this analysis is based on per-vehicle records,
it is not as flexible as the analysis which can be carried out in Traffic Executive. This software will carry out each analysis action on raw axle event records, allowing vehicles to be re-classified according to different criteria if required.
o Metrocount have also pointed out the range of different (and customisable) classification schemes available for use with their equipment, through the Traffic Executive software.
o Gloucestershire Highways is happy to endorse these comments and thoroughly recommend the Traffic Executive software for use on its own or in conjunction with manufacturer-independent databases, such as C2.
Transport Monitoring Team, Imperial Gate Business Park, Corinium Avenue, Gloucester, GL4 3BW www.gloucestershire.gov.uk
Email: [email protected] Tel: 08000 514514
Report Ref: Spring 2011 ATC Trial Report – Issue 3 Page: 21 of 21 Author: PS Checker: DJ Date: April 2011
Appendix 2
Contact details for participating suppliers
Applied Traffic Contact: Derek Wager Tel: 01582 528682 Email: [email protected] Web: www.appliedtraffic.co.uk CA Traffic Contact: Chris Hennebry Tel: 01296 333499 Email: [email protected] Web: www.ca-traffic.com Golden River Traffic Contact: Mark Chermside Tel: 01869 362809 Email: [email protected] Web: www.goldenriver.com Metrocount UK Contact: Roger Macklen Tel: 020 8782 8999 Email: [email protected] Web: www.metrocount.com Traffic Technology Contact: Richard Toomey Tel: 01280 847711 Email: [email protected] Web: www.traffictechnology.co.uk ViaCount Tel: 0049-2171-504930 Email: [email protected] Web: www.viatraffic.de