German authorities use CB-radio message to reduce accidents in roadworks
First publishedin ITS International
A CB radio trailer in position with grey boxes housing the radar (centre) and two four-lanugage antenna
Citizen Band radio is proving useful to prevent accidents in Germany’s roadworks.
In common with other German Länder (federal regions) with large volumes of commercial vehicles using their trunk road networks, Bavaria had been experiencing high levels of road traffic accidents (RTAs) involving heavy trucks in the vicinity of minor motorway maintenance sites. This was despite the extensive visual warning regulations published in the German federal road safety audit (RSA) guidelines for the protection of site operations. Typically, these RTAs involved rear-end collisions between trucks and roadworks vehicles, following failures by drivers of the former to brake in time. They were occurring in both short-term, static repair sites and mobile maintenance operations such as verge mowing or tree pruning.
The region’s northern motorway network had been experiencing over 30 such collisions a year resulting in total losses of maintenance vehicles, by far the most of these caused by trucks. This also meant unacceptably high incidence rates of injuries to both drivers and maintenance personnel.
In response, the Autobahndirektion Nordbayern (ADNB/Motorway Directorate for Northern Bavaria) researched three possible solutions: visual, tactile and acoustic. The first was deemed insufficient on its own, because of the evident failure of existing systems, especially on routes with high traffic flows. At the same time, the absence of new systems that could improve the situation was evident as modern LEDs do not solve the problem of being seen too late by trucks separated by small gaps.
The tactile solution, most obviously in the form of temporary road humps, was not going to be of use with mobile roadworks. The result was an acoustic alternative, using an intelligent alarm system. COST OF EQUIPMENT PER TRALIER:
FOR A FOUR-CHANNEL SYSTEM:
FOR AN EIGHT-CHANNEL SYSTEM:
INSTALLATION COSTS (RETROFIT):
MAINTENANCE PER TRAILER:
c €90 (US$124) pa
REDUCTION IN TOTAL LOSSES OF CONSTRUCTION VEHICLES:
Developed by wireless technology specialists B&E antec, the system communicates directly with the Citizen Band (CB) radios of drivers heading for potentially hazardous sites.
Research showed that, depending on the nationalities of those using German motorways, on average 75% of trucks are equipped with CB radios. Of their drivers, 95% are constantly listening in; 90% of those to standard channels.
The chosen solution involves positioning basic trailers, owned by the Directorate for the use of its motorway maintenance teams, at strategic points in advance of roadworks sites. The trailers are equipped with battery-powered modules with antennae for continuously broadcasting warning messages to CB radio users.
The antennae send out an initial alert tone followed by the message ‘attention – danger spot’ in up to eight languages. There are both four- and eight-language versions with Bavaria, as a major freight transit region, using eight.
The trailers also carry integrated, off-the-shelf Doppler radar units for measuring traffic speeds. These enable the system to switch off automatically during periods of congestion, when traffic speeds fall below the danger level, to avoid drivers being distracted by unnecessary warnings. Transmission stops when the radar detects that the speed has fallen below 30km/h.
The system is limited to a range of 300m, to minimise power consumption. Using appropriate antenna technology, it is also possible to restrict transmissions as far as possible to a single direction along the motorway, with the angle limited to screen drivers travelling in the opposite direction from receiving unnecessary messages.
Since the introduction of the scheme, the directorate has brought more than 230 equipped trailers into use and as they are small they can easily be moved, as maintenance progresses along the autobahn.
A mike makes CB radio use safer
The ADNB’s example has been followed by other German federal states, including neighbouring Hessen and its own neighbour North-Rhine Westphalia; and also by Austria, in the system’s First national-scale implementation.
ADNB head of ITS Thomas Zeh told ITS International: “As most trucks in Germany still have CB radio, this communications medium – even if ‘old’ - seemed very well suited. Again, with the proper setting of transmission power and directed antennae, it is locally restricted, for safety.
“It operates reliably at both static and mobile maintenance sites. Another important point is that it involves no additional tasks for maintenance personnel, as even function tests can be performed easily. Both road crews and truck drivers have evaluated it as being ‘very positive’.”
Surveys in Hessen have shown that the behaviour of truck drivers using the system is significantly different from those that are not. This is partly because they often hear the warning messages before they can see the roadworks site.
“Obviously”, says Zeh, “the system cannot avoid all accidents, but it has proved to be a major contribution to improving safety.
Following its introduction in 2010, the rate of total loss of construction vehicles in Northern Bavaria caused by rear-end collisions has fallen by about 30%.” Subsequent deployment by Austrian Toll road operator ASFINAG has delivered similar results.
“As a success story, this should be implemented throughout Europe, adapted to the prevailing languages and CB radio channels used by truck drivers in individual regions. There should also be scope for future expansion of the technology which, with the help of automated driver assistance systems, could lead to a similar solution being developed for passenger cars,” says Zeh adding that pilots have already been carried out in Hessen.
The system has won an award for the medium-scale deployment making the most notable impact in achieving the objectives of the European EasyWay programme, aimed at reducing congestion and accident levels and enhancing the environment.
Interestingly, in the US, the Florida Department of Transportation
’s Fourth District is also recruiting this ‘old’ technology into a US$4.5 million anti-crash and congestion scheme along a 74km stretch of US route 27- the First time in an ITS implementation.
ITS managers wanted to make sure that truck drivers received vital traffic information. The CB radio takes its place among a more conventional array including CCTV, dynamic message signs, vehicle detectors, highway advisory radio (HAR) and a roadway weather information system. Introduced in the US in 1945, and having lost of its attraction for general populations following the emergence of mobile phones and the internet, CB radio remains popular with truckers in both Europe and North America. Upgrading with hands-free microphones has made it safer to use.
Legal status will boost ITS database
As this issue of ITS International went to press, IBEC (the International Benefits Evaluation and Costs Working Group) was on the cusp of finalising its new status as an independent legal entity, registered in Switzerland. Says chair Tom Kern, executive vice-president of ITS America: “Why become a legal entity?
“Because our greatest resource is an international and cost-cutting membership. Men and women from public agencies, research institutions, and private companies offer a wealth of tacit knowledge on evaluation and cost benefit. Their writings on these subjects offer a body of knowledge and learning that can offer instruction and experience to organisations deploying ITS on every scale.
“As a legal entity, IBEC hopes to offer them opportunities to engage with its membership to expand their base of evaluation and cost benefit knowledge. This can be via consulting arrangements, studies, development of education and training materials, and procurement of speakers and presenters – all focused on the importance of validating and guiding the application of ITS approaches to enhance transportation.
“The information challenge that all deployment agencies face is what IBEC plans to take on, by filling the current void with case studies, lessons learned, best practices, teaching materials and valuation protocols. Transportation agencies can then make financially prudent and cost-effective technology decisions to improve efficiency and safety, reduce congestion, and minimise carbon footprints.”
IBEC emerged formally in 2002 as the initiative of a cadre of committed ITS professionals who believed that effective deployment is enhanced by the application of solid evaluation and assessment protocols. Its 500-plus membership represents all world regions, and it holds direct responsibility for a swathe of programming for ITS world congresses, with work already under way for the 07-11 September 2014 edition in Detroit, US.
Kern told ITS International: “IBEC hopes that its status as a legal entity will complement its world congress programming and elevate the importance of evaluation on the march towards widespread interoperable ITS deployment. For their help in holding this vision, I thank my predecessor chairs; our president, Eric Sampson; and AECOM, our secretariat for many years”.