Slipperiness detector radios ice warnings

February 06, 2013 // By Christoph Hammerschmidt
The VTT Technical Research Centre of Finland has developed an automatic slipperiness detection system for cars. The system warns vehicles in advance of a road’s actual slipperiness. If the road becomes slippery, other vehicles arriving in the area will also be warned immediately. The communication scheme resembles car-to-x communications but does not depend on such an infrastructure.

The research center claims that its system makes use of an novel real-time method of obtaining information on a road's actual slipperiness. 
Slipperiness detection is based on a method 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”, says Senior Scientist Kimmo Erkkilä.

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.

Image: The ice warning system developed by VTT makes use of multiple channels to communicate the messages. For full resolution click here .

Various vehicle-based terminal devices can be used to join the system, under the condition that 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. 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 device. As well as through vehicle terminal devices, this information can be utilised via many other communication channels, such as smart phones, the national media, weather forecasts or roadside signs.