Benefits and Limits of Recent Floating Car Data Technology – An Evaluation Study

This paper describes how Probe Vehicle Data or Floating Car Data (FCD) collected from vehicle fleets are an excellent technology for the traffic surveillance needed to support various applications of Intelligent Transportation Systems (ITS). Data from an FCD-fleet result in travel time maps of the area under surveillance. Despite the simplicity of such a system, traffic surveillance based on such data has some disadvantages. The main shortcoming is caused by the insufficient penetration rate which has been achieved so far. Operating systems of Floating Car Data use at maximum several hundred up to few thousand vehicles in urban street networks composed of some ten or even hundred thousands of road kilometers. Questions arise about the reliability of travel time information on routes derived by very few probe vehicles. Unfortunately, most systems lack of a systematic performance evaluation. In this contribution, a taxi-based FCD system with about 500 taxis, operational running in Nuremberg, Germany, is tested with data from a measurement campaign. This campaign of four days duration had been conducted along a main street in Nuremberg using license plate recognition to estimate the travel times along the street. These data are compared to the travel time calculations obtained from the taxi-FCD system. The main result is that the FCD system is particularly able to detect jammed situations and the travel times calculated by the system deliver valuable data for mobility and traffic information systems.