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.
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
Reflecting the rapid growth in ELV traffic equipment,
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
Detection
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
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
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
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
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
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
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.
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
Mike Payne, of group member company
"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
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.