Natural interaction framework for pedestrian navigation systems on mobile devices

Abstract

Mobile Augmented Reality applications base on navigation frameworks try to promote interaction beyond the desktop by employing wearable sensors, which collect user's position, orientation or diverse types of activities. Most navigation frameworks track location and heading of the user in the global coordinate frame using Global Positioning System (GPS) data. On the other hand, in the wearable computing area researchers studied angular data of human b o y segments in the local coordinate frame using inertial orientation trackers. We propose a combination of global and local coordinate frame approaches and provide a context-aware interaction framework for mobile devices by seamlessly changing Graphical User Interfaces (GUIs) for pedestrians wandering in urban environments. The system is designed and tested on a Personal Digital Assistant (PDA) based handheld prototype mounted with a GPS receiver and inertial orientation tracker. It introduces a method to estimate orientation of a mobile user's hand. The recognition algorithm is based on state transitions triggered by time-line analysis of pitch angle and angular velocity of the orientation tracker. The prototype system can differentiate between three postures successfully. We associated each posture with different contexts which are of interest for pedestrian navigation systems: investigation, navigation and idle. Thus, we introduce the idea that once orientation trackers became part of mobile computers, they can be used to create natural interaction techniques with mobile computers. The prototype is tested successfully in two urban environments: Sabanci University campus area, . 9th International Istanbul Biennial venues in Beyoglu, Istanbul.