Speed Aware – a mobile app prototype for the promotion of responsible driving

Abstract

This paper addresses the promotion and awareness of responsible driving and road safety through the development of a very simple to use mobile application prototype, Speed Aware. This application provides users with speed limit information on roads they are travelling on, together with a journey logging feature that allows off-line self-review of driving behaviour. Tracked journeys can be displayed on a map and the trace shown as a heatmap, comparing the vehicle speed to the road speed limit. Furthermore, an audible alarm is emitted whenever the vehicle is travelling at a speed higher than the legal limit. At the heart of this app is a map matching algorithm, which matches raw Global Positioning System (GPS) data to the road network. Five map matching algorithms are implemented and compared on the basis of real-time performance and accuracy. A ground truth dataset of GPS traces in dense, urban, and sub-urban environments, together with TraceView, a trace visualisation and management tool, were developed. A modified version of a weight-based topological algorithm achieved accuracy of 94.9% at a GPS sampling frequency of 1Hz. This algorithm, together with three of the reviewed map matching algorithms, were implemented on a mobile device and subjectively tested for realtime performance.