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Saturday, December 23, 2006

Traffic Information with all the senses

When it's not building neck-numbingly bad seats, or eye-wateringly ugly executive saloons, BMW is actually quite a clever company. It's got next-generation telematics right. The best way to improve safety is to share up-to-the-second data about road conditions with the cars that are actually on the road. And the best way to do this without needing to violate the laws of physics is to adopt a peer-to-peer system, in which cars communicate directly with their neighbours, rather than going via a central control point. Of course it helps to have a central co-ordinating point as well – partly to collate data and to send it to vehicles that are out of sight of other cars, but also to check whether the data from any particular car is trustworthy. This is how BMW's XFCD (Extended Floating Car Data) system seems to work

To date, telematic services have only worked through the intermediary of a traffic centre which compares and analyses up-to-the-minute traffic information from various sources and then, for example, passes on traffic jam warnings to all participating vehicles. So vehicles have been playing a role in providing specialist traffic information services for years. With FCD, the Floating Car Data System, the vehicles - which are fitted with a GPS receiver and a mobile phone module - send information about their speed and position to the traffic centre. Cars known as 'Floating Car Data Vehicles' have been on the roads since 1999, "some 40,000 in Germany", according to traffic researcher Susanne Breitenberger from the BMW Group. However, according to Breitenberger, the drawback of this system is that "it costs a relatively large amount to transfer a relatively small volume of data".So she and her team of traffic researchers are working on an advanced version of data logging called Extended Floating Car Data, XFCD for short.

XFCD cuts out the middle man - the traffic control centre - and the vehicles can swap the information they have calculated directly with one another," Breitenberger describes the benefits. XFCD uses much of the vehicle-generated data which is already available in the vehicle in order to obtain a comprehensive picture of the traffic situation: Are the lights on, are the wipers working, what are the rain and ABS sensors reporting? In the future, the special software - very little additional equipment is required - will be able to calculate not only travel times, but also congested exits and junctions, jam conditions and the weather and road conditions. Conclusions can be drawn about local risks such as black ice and aquaplaning, and on the current traffic situation, directly within the vehicle. Finally, the car sends information to the traffic centre and transmits information direct from the vehicle to other affected vehicles in the area. Another benefit is that "XFCD is more cost-effective because its 'back-channel referencing' sends only that information which is really needed to the traffic centre," says Breitenberger. This means that a vehicle with XFCD which is stuck in a traffic jam and has been given the information over the radio can register that the information is correct, so it is not reported to the traffic centre again. The result: "The system generates traffic information and sends this on a 'need to know' basis. By using the new XFCD system, we are saving money on communication relative to the FCD system, while at the same time improving the quality of the traffic information put out," says Breitenberger. At the same time, the system not only enables the information calculated on board to be compared with the traffic reports on the radio, but XFCD also checks that the traffic jam reports are still accurate. So the system sends up-to-date information directly to the traffic centre if, for example, a traffic jam has cleared.

What makes XFCD special is that the customer does not have to fit additional hardware into the car. The system works using the existing vehicle architecture, only software is added," stresses Breitenberger. After all, plenty of information besides the speed is already recorded in the car. The introduction of modern on-board computer systems allows the combination of a wide range of available data. This can be used to find out information about the traffic, the road conditions and the current weather. This includes data from, for example, the navigation system, the headlights, the air-conditioning system and rain sensors on the windscreen wipers. The system processes this data and determines the current condition of both traffic and the roads. This means traffic and risk situations, such as black ice, rain or fog, can be detected immediately. "For example, adjusting the Dynamic Stability Control (DSC) in conjunction with a low external termperature, high wiper frequency and correspondingly low speeds translates into a local risk of slipping because of ice or oil on the road," explains Breitenberger. The traffic researcher is optimistic that XFCD can be implemented quickly. Based on her calculations, which were drawn up for the city of Munich, if there is just 7.3 percent takeup on XFCD technology in vehicles, the traffic situation could be reliably determined on 80 percent of the main streets of the city.

The BMW Group has already proved that the new technology works in practice by demonstrating the system on a special test track as part of the "Innovative Mobility Showcase" in San Francisco. As its base scenario, the BMW selected a situation where one of the three vehicles came onto a slippery road surface. The vehicle processes all the information from the vehicle sensors and warns the following vehicles in real time. At the same time, the data is forwarded to a traffic centre. Information gathered by XFCD vehicles on the traffic situation on the public highways can be viewed on the internet and made available directly as traffic information to all road users.

XFCD is being implemented at the BMW Group in line with the BMW ConnectedDrive system. The basic philosophy is the networking of the driver, the vehicle and the environment using telematics, online and driver assistance systems in order to make driving safer and less congested.

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