<XML><RECORDS><RECORD><REFERENCE_TYPE>3</REFERENCE_TYPE><REFNUM>8309</REFNUM><AUTHORS><AUTHOR>Williamson,J.</AUTHOR><AUTHOR>Strachan,S.</AUTHOR><AUTHOR>Murray-Smith,R.</AUTHOR></AUTHORS><YEAR>2006</YEAR><TITLE>It’s a Long Way to Monte-Carlo: Probabilistic GPS Navigation</TITLE><PLACE_PUBLISHED>ACM International Conference Proceeding Series; Vol. 159, Proceedings of the 8th conference on Human-computer interaction with mobile devices and services, Helsinki, Finland http://doi.acm.org/10.1145/1152215.1152234</PLACE_PUBLISHED><PUBLISHER>ACM</PUBLISHER><PAGES>89 - 96</PAGES><LABEL>Williamson:2006:8309</LABEL><KEYWORDS><KEYWORD>GPS</KEYWORD></KEYWORDS<ABSTRACT>We present a mobile, GPS-based multimodal navigation system, equipped with inertial control that allows users to explore and navigate through an augmented physical space, incorporating and displaying the uncertainty resulting from inaccurate sensing and unknown user intentions. The system propagates uncertainty appropriately via Monte Carlo sampling and predicts at a usercontrollable time horizon. Control of the Monte Carlo exploration is entirely tilt-based. The system output is displayed both visually and in audio. Audio is rendered via granular synthesis to accurately display the probability of the user reaching targets in the space.We also demonstrate the use of uncertain prediction in a trajectory following task, where a section of music is modulated according to the changing predictions of user position with respect to the target trajectory. We show that appropriate display of the full distribution of potential future users positions with respect to sites-of-interest can improve the quality of interaction over a simplistic interpretation of the sensed data.</ABSTRACT></RECORD></RECORDS></XML>