Abstract

reduction in recent years, the modules became increasingly popular in the leisure sector as well and are state of the art now. The modules are used in sport devices and fitness watches for navigation and activity tracking like bicycling, running, hiking etc.

In accidents where bicyclists or pedestrians are involved the likelihood of facing fitness tracking devices during the accident reconstruction is increasing significantly. When working with the recorded data it is important to understand which accuracy for the different data items can be achieved typically.

This paper evaluates the accuracy of several modules and the usability of the tracking data for accident reconstruction is discussed. Various factors influencing the accuracy like signal reflection and shading in urban areas, satellite configuration and others are discussed.

In order to evaluate the accuracy of the different GPS tracking modules in terms of lateral and longitudinal position determination as well as speed measurement, test drives were performed under ideal conditions on the DSD test site. A calibrated dGPS unit with an accuracy of 1 cm for position and 0.05 km/h for speed is used as the reference signal (provided by Alp.Lab). As test vehicle a mobile robot, which can follow a given path and velocity course, was used. Furthermore, tests in rural and urban areas under realistic conditions were conducted for illustration and comparison of the results.