Idris at World Congress 2008
 |
|
| |
|
|
|
Location: A30 trunk road from Exeter to Honiton, Devon, United Kingdom
Client: Connect A30/A35 Limited.
Application: Shadow Tolling
ITP: Quixote Traffic Corporation
Product: Idris DR410 & Drakewell C2 system
Project: D.B.F.O (Design Build Finance and Operate). To provide reliable and accurate data recording technology with a user friendly interface for traffic monitoring on the A30.
Background: The A30 is a privately operated road set up under contract between the Highways
Agency and Connect A30/A35 Limited. The construction of the trunk road from Exeter to Honiton
began on October 1st 1996 and was completed on the 31st March 2000. Connect was awarded the
contract to replace the existing congested road as well as a 9km dual carriageway bypass. The
bypass construction was to take the trunk road traffic out of the picturesque villages of Puddletown
and Tolpuddle in Dorset. This carriageway was intended to ease congestion, which inturn,
would enhance the environment and improve safety in these small villages. The scheme would also
provide additional capacity to improve traffic flow and help to accommodate future predicted traffic
growth.
History: For some time the volume of traffic using the A30 had been an issue as the flow varried
with significant seasonal variations. When traffic was at it's peak during the holiday periods, there
could be in excess of 24,000 vehicles traveling the route with HGV's making up around 10% of the
figure.
Project Detail: A contractor awarded a D.B.F.O project is paid by shadow tolling the stretch of
road. Shadow tolling is tolling but without the physical presence of tollbooths and the road users do
not actually pay charges to the operators. The term "shadow tolling" is used when there is a
requirement to record the number and type of vehicles using a road in order to set a value against
this usage. The Highways Agency pay Connect for the A30 project on an annual basis depending
upon the volume of traffic using the road. For this reason it is paramount the shadow tolling system
meets the highest levels of accuracy so neither party is under or over paid.
Drakewell Ltd, who specialise in data collection and traffic analysis reporting, were contracted by
Connect to carry out the shadow tolling on the A30. Drakwell implemented their C2 software and
the Idris DR410 product to gather the data required to form the system.
How it works: The data collected was sent to Drakewell's C2 system which provides a platform for
the data to be recorded onto. From there the data can be viewed and stored in an industry standard
database. The C2 system is ideal for manipulating statistics and data into a usable format for
shadow tolling statistics and issuing the various types of report.
Idris counts and monitors the number of vehicles traveling the A30 via fourteen DR410 units housed
in road side cabinets. The DR410 achieves vehicle count accuracy of 99.9% and was selected as the
data recorder for this project due its high accuracy levels. Amongst other information Idris records
the vehicles direction of travel, length, speed and class. This is achieved by the DR410 analysing
vehicle signatures as they travel over an inground
loop array and then processing this inductive
loop data. Patented Idris algorithms translate the information into accurate per vehicle records. The
DR410 is able to place vehicles into a number of classifications however, for this project only two
classifications were required; vehicles over 5.2m in length and vehicles less than 5.2m. The
vehicles in the higher category are likely to be heavy goods vehicles, therefore a higher fee would be
charged as they contribute more to the wear and tear of the road surface. The data, i.e. the number
of vehicles using the road per day and their size, is collected and forms the revenue charge passed to
the Highways Agency.
Results: Using Idris as part of the shadow tolling system means data can be continually collected,
in all weather conditions and in total congestion. The accuracy and end results are achieved
regardless of the various traffic situations, from total congestion (stop/start) through to free flow.
The accuracy of the technology is due to Idris' ability to distinguish between vehicles towing,
tailgating and ones that straddle lanes. This level of accuracy allows both Connect & the HA to be
confident in their financing and payment for the project.
The Idris DR400 range is the ideal choice for any data recording application.
|
|
