Volvo has completed a research project using magnets in the roadway to help a car determine its position – the study is aimed at determining reliable and highly accurate positioning, one of the crucial issues in the development of self-driving cars.
A 100-metre long test track was created at the company’s testing facilities in Hällered in Gothenburg, Sweden, where a pattern of round ferrite magnets measuring 40 x 15 mm were placed 200 mm below the road surface, and a test mule was equipped with several magnetic field sensors. The programme evaluated key areas such as detection range, reliability, durability, cost and the impact on road maintenance.
While established positioning technologies such as GPS and cameras have limitations in certain conditions, road-integrated magnets remain unaffected by physical obstacles and poor weather, effectively creating an invisible ‘railway’ that could pave the way for a positioning inaccuracy of less than one decimetre (10 cm).
Aside from its potential in the field of autonomous driving, road-integrated magnets open up a number of other possibilities. The incorporation of magnet-based positioning in preventive safety systems could help prevent run-off road accidents, and there’s also a possibility of more efficient utilisation of road space, with accurate positioning allowing lanes to be narrower.
The automaker already has a large-scale autonomous driving pilot project in place, in which 100 self-driving Volvo cars will use 50 km of public roads in everyday driving conditions around the Swedish city of Gothenburg.