Sound-guided running Using GPS and binaural audio in an exercise application

Abstract

This report describes the development of an exercise application for Android smartphones, called Run For Life. It combines the sensors found in present day smartphones with spatial audio feedback, creating an exercise application with virtual sound sources. The idea of combining spatial audio with smartphone sensors is new and the research is limited. By using the GPS sensor to calculate both the user’s position and orientation, the project attempts to combine the spatial audio achievements made by Lawitzki (2012) with the running game elements of applications like Zombies, Run!. The audio was implemented using general, non-individualized head related transfer functions. An attempt to use the gyroscope sensor to calculate the orientation of a user standing still was made, often resulting in a confusing sound. The application’s main mode is game inspired. By providing a randomized running route and audio feedback to guide the user though its checkpoints, the application aims to enhance regular exercise. Run For Life also presents the opportunity for the user to view statistics of previous running sessions. A lot of time was put into designing the user interface in a way that makes the application appealing. The report concludes that it is hard to make the perception of an angle realistic to the user because of the difficulty in sensing a user orientation. GPS technology is still too inaccurate to create a perfect perception of the sound direction by itself. Finally, determining a user’s orientation is not reliable while the sensor is not at a fixed position relative to the user ears; a head-mounted sensor device would probably avoid most of these problems and provide a more realistic perception.