Integrate systems to reduce roadside infrastructure

David Crawford reviews promising current developments. Instrumentation of the road infrastructure has grown to become one of the most dynamic sectors of the ITS industry. Drivers for its deployment include global concerns over the commercial and environmental pressures of traffic congestion, the importance of keeping drivers informed throughout their journeys, and the need to reduce accident rates and promote the safety of all road users, for example by enforcing traffic safety rules.
Air Quality & Weather Systems / January 27, 2012
Dark snow covered road
Swarco is now in production with its Futurlux LED streetlight, designed to cut local authorities' costs, seen here installed in wintry conditions in Vaasa, Finland

David Crawford reviews promising current developments

Instrumentation of the road infrastructure has grown to become one of the most dynamic sectors of the ITS industry. Drivers for its deployment include global concerns over the commercial and environmental pressures of traffic congestion, the importance of keeping drivers informed throughout their journeys, and the need to reduce accident rates and promote the safety of all road users, for example by enforcing traffic safety rules.

It is also a fast-changing sector. It faces pressures on costs, from budget-conscious public administrations worldwide and, for both cost and environmental reasons, for rationalisation. One promising path is the development of integrated solutions that can achieve the multiple use of existing or planned equipment, with some potentially highly relevant initiatives on both sides of the Atlantic (see Sidebar, 'Integration').

This article is a snapshot. It takes a look at a selection of the many recent and current developments and trends in the field of signals, displays, camera technologies and traffic management systems.

One of the more visible phenomena is the steady advance of LED deployment in traffic signals and VMS, where implementation case studies show that its 'energy-sipping' characteristics can reduce power usage by 80 per cent by using the latest technology, while offering a useful equipment life of between five to seven years. The highest level of take-up, at an estimated 70 per cent-plus, is in North America, double the figure for Europe - although the advent of effective Extra Low Voltage (ELV) systems has meant that new installations are now predominantly LED-based.

Keith Manston, head of product management with 678 Siemens Traffic Solutions, also points to the way in which more and more local administrations are implementing retrofit programmes. Existing sites can then be updated to LED, achieving similar power savings to those offered by new ELV solutions, he says.

Reflecting the rapid growth in ELV traffic equipment, 189 Siemens has launched a low-level access traffic signal pole, designed to minimise the need to work at height.

Initial costs for LED technology are higher but solutions are available for road authorities. In Pennsylvania in the US, for example, where local administrations were facing a 35 per cent increase in electricity charges following a 2010 uncapping of electricity rates, the Energy Resource Center of the SEDA-COG grouping of local authorities set up an LED Traffic Signal Conversion Project for members that had not yet made the transition. This resulted in a per cent saving in equipment costs and projected annual avoided aggregate cost savings of US$48,746 with an aggregate annual energy reduction of 244,216 kWh.

The use of Fresnel or programmed visibility lenses to focus light output and ensure that what is needed is being aimed in the relevant direction is another encouraging development. It allows the use of fewer LEDs and thus lower power use and longer LED lifetimes.
Among traffic signal head suppliers, Swarco Futurit is claiming worldwide interest in its Futura product, whose eco-design principles have won it an award from the Austrian Federal Ministry of Transport for its contribution to climate protection. The company has also installed an LED-lit feedback window in its new TOUCH SOUND pedestrian signal activator that gives people waiting to cross optical, acoustic and haptic cues.

Current work in the area is being centred on determining the reliability of having fewer LED light source solutions without prejudicing product lifetimes. One company, communications infrastructure specialist 525 Telent, is testing its latest-generation CLS (Central Light Source) optic, which incorporates two LEDs and is rated at about 9W bright and 5W dim, compared with a previous optic using 11 LEDs with 15W power rating.

Detection 527 Digital Recognition Systems's integrator-oriented approach to number plate recognition technology has led it to develop and pilot its iSharp camera range and NumberWorks recognition engine. This reflects the growing deployment of IP cameras in ANPR systems and the challenges that their compression methods present, with high-frequency components impacting on recognition performance and imposing higher loads on power and processing capability.

The camera, based on EverSharp lens technology, uses cat5 ethernet cable to transmit two uncompressed (colour and infrared) video signals together with power and  communication, enabling undistorted content for up to 500m without repeaters.

Conceived with global markets in mind, NumberWorks replaces direct template matching with font-free contour matching. The company has recently partnered with a Japanese company to develop a system for reading Japanese number plates. It is developing an on-chip version, to avoid computer reliance, and working with integrators in the US, Europe and the Asia/Pacific.

The UK 503 Highways Agency has specified 819 NavTech Radar's Clearway radar incident detection system for the 1.8km twin-bore Hindhead Tunnel on the A3 trunk road in Surrey, south of London, with tunnel control system specialist 530 PDS Ltd responsible for the SCADA control component and integration with other tunnel systems. Built to relieve serious congestion, the tunnel, which opens officially in June 2011, is the longest non-estuarial tunnel in England.

The advantage of radar in dealing with incidents is its ability to detect vehicles and people through smoke in the event of a fire. The solution required a bespoke modification of the interface to enable seamless integration with the control system. It also had to be able to handle a change to the tunnel operating mode so that it continues to operate and generate alarms when a bore is operated in contra-flow mode (when delineation is achieved by the use of Astucia's hardwired bi-directional road studs). The company has also successfully trialled a radar-based system for safety monitoring of hard shoulder running schemes on motorways.

Video imaging processing specialist 5574 Traficon has recently taken on the challenge of integrating the needs of vulnerable road users, such as pedestrians and cyclists, with those of vehicle users. Says the company's Stijn Vandebeurie: "Cities are already crowded, with people on foot, two wheels and four wheels jostling for right of way. So, in the not-too-distant future, cities are going to need more intelligence so that people can live and travel safely in these crowded, fast-paced urban jungles." He reports widespread interest from the company's SafeWalk and C-Walk pedestrian detectors, introduced in 2010. The SafeWalk 3D stereovision detection system uses two of the Complementary Metal-Oxide Semiconductor (CMOS) sensor cameras that are deployed singly in its TrafiCam platform to account for the extent to which pedestrians can vary in size and profile.

The system captures, in real time, a stereo image for video processing (to confirm that the subject is a person), then checks whether it is moving or stationary, in order to calculate precisely when a pedestrian enters or leaves the pre-defined detection zone.

C-Walk, designed to track pedestrians as they cross a road, uses the basic TrafiCam platform to detect rate and direction of movement. Add-on units make it possible to deploy units to give advance warning to drivers that someone is crossing the road by triggering an alarm or warning signal to oncoming traffic; and/or to hold the green phase for a pedestrian who is crossing slowly or has stopped within the zone.

The two systems work together, for example at intersections where they generate input for traffic controllers.

Traffic management

France's first deployment of automated reversible-lane traffic management went live in 2010 on the congested St Nazaire Bridge over the River Loire. The e10 million scheme deploys new vehicle guidance technology in the form of illuminating road marking technology that is not yet fully covered by French highway regulations.

 The key innovation is the identification of a reversible lane on both sides by the use of lines of illuminating road studs set into the carriageway alongside it. The studs, developed for the project by French traffic safety specialist manufacturer 531 Cryzal, use 532 Luxeon super LEDs to deliver 300 lux at 1m. When activated, they show red in the direction of travel to create the impression of a continuous red line which it is illegal to cross.

Luminous lane marking is also in operation on the Southern Expressway in Adelaide, Australia, a three-lane, one-way reversible motorway which feeds traffic to and from the city centre and the Adelaide Hills. It changes direction around midnight and midday to accommodate the morning and evening peak traffic flows, and needed a traffic management solution to reinforce these - particularly for afternoon peak traffic entering the motorway.

The two-stage solution involved: the installation of 30 white Astucia intelligent road studs to provide delineation across the normal lane lines in the morning; and the installation of a line of 30 red studs to help traffic entering the motorway at a junction. The aim was to discourage motorists from changing lanes until they were further along the road, and had reached a point where their speeds were more compatible with those of vehicles already on the motorway, travelling at 80km/h, and where sight distances were better.

For vehicle classification on highways, Swiss company 535 ECTN has developed a traffic information collector using 536 Sick LMS111 laser scanners which can identify up to 28 different classes of vehicle (including those changing lane) and map them into user-defined categories according to project specifications for applications including free-flow tolling. The system can automatically trigger external third-party systems including DSRC and ANPR enforcement cameras and DSRC systems, enabling close integration and a single-gantry solution.

Signs of progress

Long familiar on interurban roads, where they are developing scope for the display of additional features including journey-time estimation, VMS are now moving steadily into new, more specialised deployment areas. In a pilot ending in mid-2011, Swarco Traffic Systems has installed an LED-based HGV parking information updating system at sites along the A5 motorway in south-west Germany.

Responding to a known national deficit of 15,000 spaces, the system shows the number that are available at the sensor-equipped upcoming site. The aim is to minimise the incidence of vehicles searching often fruitlessly, and sometimes dangerously (if, for example, drivers become over-tired), for somewhere to stop.

German automobile association ADAC forecasts that, over the period to 2025, there will be an increase of more than 80 per cent in levels of freight traffic. Most of this will fall on the federal motorway network.

New needs for signs are also emerging in built-up areas. UK company VMS Ltd now has its 844 Pegasus urban signs in operation with 1466 Transport for London, which has played a central role in the development of the system. Pegasus is a scaled-down version of a standard motorway-type installation, using the same LED technology, and is designed for integration into the built-up streetscape.

It comes, for example, in both portrait and landscape formats, to accommodate space-restricted site conditions. But VMS Ltd deputy chairman Roger Stainforth sees wider applications, reflecting the fact that local authorities increasingly find their urban roads interfacing with motorway networks.

"Many stretches of motorway which were rural when they were initially designed are tending to become part of the urban scene in the wake of the development of out-of-town business parks and shopping malls. Being able to advise drivers on urban roads of the conditions that lie ahead of them in advance of their joining a motorway, by using signs with the same performance and functionality, is obviously advantageous."

Originally developed mainly to cope with event traffic, permanently installed Vanguardreg digital dynamic message signs from 32 Daktronics are now helping to decrease traffic congestion around busy venues in central Minneapolis, USA. The 42-sign array uses text and full-colour graphics to guide travellers into and out of the available parking sites.

The city approached the company in anticipation of increased traffic flows following the 2010 opening of its new Target Field baseball park, adding to those already being generated by the Minneapolis Convention Center and the city's downtown theatre district. Its control centre can change the messages individually or in groups, with the capacity for rapid alteration being a key requirement of the specification.

538 Versilis's dynamic SwiftSign has just won third place in the 2011 833 American Traffic Safety Services Association (ATSSA) Innovation Awards. Conceived as a halfway house between conventional VMS and static signs, and designed to complement the company's remote-controlled Swiftgate system for highway lane closures, which uses a series of pivoting 'gates', it is increasingly finding uses as an independent unit for applications such as work zone or roadway surface conditions warnings and for congestion alerts.

Solar powered to be independent of cabling, and with its own pivoting panel remotely operated from a control centre or by mobile or via a website, it can carry up to three alternative messages by using a 'book-style' page-turning mechanism.


Integration

The growing volume of equipment being installed or considered for deployment on the road infrastructure is generating close interest in multiple use of ITS arrays, for example to gain maximum benefits from those already in place. The US-headquartered 38 Federal Signal Technology group, for example, is offering its Lane-in-a-Box (L-Box) as a new approach to delivering services that depend on roadside vehicle detection or information collection.

Mike Payne, of group member company 529 Diamond Consulting Services, told ITS International: "The concept signifies the way in which all the 'clever bits' are essentially in one box rather than in many from different vendors' sub-systems, all with their own controllers on top of the overall system one, all of which have to be connected together and made to interface.

"By 'one box' we mean much less of the above. All the components can then be located on a single roadside pole, running on one processor and dispensing with ground-level cabinets or equipment racks in nearby buildings, as long as there are power and ethernet or equivalent." He sees L-Box being particularly well-suited to use on single or dual lanes, where conventional road infrastructure can be impractical. The hardware is already in production, with the controller still undergoing test, indicating second-half of 2011 product availability.

Another example is the UK's 3rd Generation Road Side Equipment (3GRSE) project, sponsored by the government-backed Technology Strategy Board with Telent as project leader and the support of ANPR specialist company 539 CitySync, transport consultancy 491 TRL and electronic tolling equipment provider 43 Efkon. The original aim was to explore the scope for integrating current and emerging Time-Distance-Place (TDP) road pricing systems into existing ITS infrastructure using UK-developed Urban Traffic Management and Control (1682 UTMC) specifications.

These are now increasingly being deployed in cities around the world, bringing global significance to the project. The desired result is to enable any existing UTMC-compliant set-up to act as a base, using its existing physical structure of on-road equipment, cabling, power supply and communications.

One obvious application would be to use existing signalised traffic junctions, whose operation is already being optimised by traffic speed and flow data, as the basis for introducing congestion-responsive charging structures. TDP road pricing would then become part of a wider network management strategy.

In return, deployment of a TDP system that is fully integrated into urban traffic control systems would provide benefits for the latter, particularly with the use of new, high-definition ANPR cameras.

The road pricing aspects of 3GRSE, where Efkon is developing the vehicle detection, charging and enforcement components, have already attracted attention from as far afield as Dubai. But the concept's modular approach has also enabled a broader look at further potential applications. Local traffic authorities are, for example, already using ANPR systems to good effect in meeting their network management needs and implementing public transport improvements including bus lane enforcement.

The project is structured around a vehicle signature, image processing and ANPR. At its heart lies a roadside data hub (RDH), developed by CitySync using its Silverbird processor. This can interface with a UTMC common database, allowing a 3GRSE system to transmit vehicle detection records for traffic management applications.

One spinoff currently being actively explored by TRL covers the potential benefits of locating an ANPR camera in a traffic signal head (for the purposes of the project, it sat above the red aspect in a larger-than-usual unit). This would benefit future TDP schemes but could also measure journey times.

TRL told ITS International: "The realisation that the system could produce additional data led us to ask: 'what else can we do with this'. One answer was that an ANPR camera mounted in the signal head could provide a 'virtual loop detector' close to the stop line at a traffic signal, not normally a natural location for a SCOOT detector.

Here, however, it could play a key role in automating the validation of a SCOOT installation - usually a manual process which calibrates the model to the street so that when it calculates that, say, 15 seconds of green are needed to clear a queue, this is what happens on the street."

Validation is necessary when a SCOOT system is first set up, and needs revisiting following changes to local traffic regulations, lane markings or traffic flows that could necessitate moving a detector. A poorly validated system will perform sub-optimally, leading to delays and congestion.

The problem is that effective validation costs time - typically half a day per junction - and therefore money. Automating the process could both save money and improve the signal optimisation.

TRL sees the results of this short investigation as promising and suggests that, with further development, it could determine a suitable algorithm could be determined. In a further enhancement, Telent is looking at ways of operating an ANPR camera through an optic lens.











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