Bosch and the Dutch map and traffic information provider TomTom have achieved a breakthrough in the development of high-resolution maps for automated driving. So far, video data has been used for this purpose. Bosch’s ‘radar road signature’ is made up of billions of individual reflection points. These are formed everywhere that radar signals hit – for example, on crash barriers or road signs and reproduce the course a road takes. Automated vehicles can use the map to determine their exact location in a lane down to a few centimetres. With this development, Bosch has become the first worldwide to create a localisation layer using radar signals, which will be indispensable for maps like these.
“The radar road signature is a milestone on the path towards automated driving. It will enable automated vehicles to reliably determine their location at all times,” said Dr Dirk Hoheisel, Bosch’s board of management member. The huge advantage of Bosch’s radar road signature is its robustness: unlike maps that rely exclusively on video data for vehicle localisation, the radar road signature also works reliably at night and in conditions of poor visibility. Moreover, the Bosch radar road signature only transmits five kilobytes of data to a cloud per kilometre – this data volume is twice as high using a video map. It is expected that by 2020 at the latest, the first vehicles will provide data for the radar road signature in Europe and the US.
“We are delighted to be able to introduce supplemental localisation data in the form of the radar road signature in partnership with Bosch. It will make self-localisation for automated vehicles considerably more robust in every respect,” says TomTom’s CEO Harold Goddijn. The two companies have been working intensively on the radar road signature and its integration into TomTom’s high-resolution overall map since the beginning of their collaboration in July 2015. Bosch is a global market leader in the field of radar sensors with 77-gigahertz technology and detection ranges of up to 250 meters. By comparison, video sensors only have a maximum detection range of 150 metres.
The main challenge was finding a way to adapt existing radar sensors for this task. When used in a driver assistance system such as automatic emergency braking systems or adaptive cruise control (ACC), the sensors detect moving objects. But in order to generate the radar road signature, they also need to be able to detect static objects, which meant that existing radar sensors had to be modified. The next generation of Bosch radar sensors will be able to provide the data required for the radar road signature. “Cars arriving on the market in years to come with the assistance functions of tomorrow will be running the map for the automated vehicles of the future,” Hoheisel added.