Vehicles are warned in advance of a road's actual slipperiness with the automatic slipperiness detection system developed by scientists at VTT Technical Research Centre of Finland.
While transmission of slippery road warnings to vehicles via, for example, SMS messages has been tested before but warnings have been based on estimates derived from sources such as weather forecasts. With the new system, it is possible to obtain direct information on road conditions. Slipperiness detection is based on a method developed by VTT, whereby changes in road conditions are detected in real time, based on data collected by the car's own sensors.
"The method entails estimating the difference in the speeds of the drive shaft and freely rotating axles in various driving situations, which enables deduction of the level of friction," said Senior Scientist Kimmo Erkkila.The system is capable of determining the slipperiness of a road on the basis of a drive of a few kilometres. The information is then passed on to the driver, before he or she has even noticed the change in road conditions.
After this, observations collected from all cars and the
related coordinates are transmitted wirelessly to a background system, which maintains a real-time slipperiness map and generates a log of the road conditions.
For each car that joins the system, the background system produces and transmits an individual data package on road conditions. This allows drivers to prepare in advance for slippery stretches of road.
Various vehicle terminal devices can be used to join the system, as long as they have sufficient capacity to carry out the slipperiness detection calculations, have a link to the vehicle's data bus, are equipped with a location tracking system and are able to connect to the background system, researchers said in a statement. Information on the level of slipperiness can be transmitted to drivers by means of warning lights, voice signals, text or symbols, according to the possibilities offered by the terminal As well as through vehicle terminal devices, thisinformation can be utilised via many other communication channels, such as smart phones, the national media, weather forecasts or roadside signs. The system fits all cars and negotiations to commercialise the system are under way.