Active safety for vulnerable road users based on smartphone position data

Smartphones have long become an omnipresent part of our life. Equipped with both a broadband internet connection and advanced GPS onboard sensors, the idea is to use them as mobile sensors for active safety systems that aim at protecting vulnerable road users such as pedestrians or cyclists. This paper gives a comprehensive analysis of today's smartphones GPS accuracy on an inner-city bicycle track. In addition, the transmission latencies of a prototypical bicycle warning system are evaluated. The results show that while the lateral deviations are still too high to allow for lane-level localization, the longitudinal accuracy as well as the transmission latencies are good enough for many active safety applications already.