Redundant and accurate vehicle positioning system is crucial for automated driving. Today there is no perfect solution yet that would meet such requirements. This project studied the possibility of adding to the vehicle positioning system a radar reading from the radar reflectors installed in the roadway. The study conclude that the radar reflectors might be a very valuable addition to the vehicle positioning system.
Dependable and fail-safe control of autonomous vehicles requires multiple independent sensors for lane detection and positioning. From analysis of modern sensing technologies, we conclude that radars are underutilized for positioning, and that they might be an enabling technology for achieving safety requirements posed by the standard ISO 26262. To fully utilize the radar potential, we have conducted a pre-study of equipping infrastructure with radar reflectors. We estimate that such reflectors should be installed in the lane markings, about 20-25 meters apart and with some kind of identification. We propose to design and evaluate a combi-reflector based on the traditional cat’s eye design, which will be detectable both by human drivers, radars and lidars. Furthermore, the combi-reflector can be equipped with a magnet for in-vehicle electromagnetic field sensor. From the redundancy evaluation performed, we conclude that the proposed solution increases the level of redundancy significantly. Therefore, the proposed solution could be an enabler for autonomous driving.