A Framework of Energy Efficient Mobile Sensing for Automatic User State Recognition

MobiSys ’09 Proceedings of the 7th international conference on Mobile systems, applications, and services.

ISBN: 978-1-60558-566-6

Authors: Yi Wang University of Southern California, Los Angeles, CA, USA
Jialiu Lin Carnegie Mellon University, Pittsburgh, USA
Murali Annavaram University of Southern California, Los Angeles, CA, USA
Quinn A. Jacobson Nokia Research Center, Palo Alto, CA, USA
Jason Hong Carnegie Mellon University, Pittsburgh, USA
Bhaskar Krishnamachari University of Southern California, Los Angeles, CA, USA
Norman Sadeh Carnegie Mellon University, Pittsburgh, USA

This paper introduces an Energy Efficient Mobile Sensing System (EEMSS) in order to collect the vast amount of information produced by mobile applications. The case is made that battery life will be spared if certain sensors are turned off when not needed. Three real-time conditions are checked to attempt to detect what state the user is in. They are: motion (coming from the acceleration), location (from the GPS), and background environment (from the microphone), and Wifi detection. Their prototype was evaluated on Nokia N95 devices with the following user states defined:

“Walking”, “Vehicle”, “Resting”, “Home talking”, “Home ent
ertaining”, “Working”,“Meeting”, “Office loud”,“Place quiet”,
“Place speech” and “Place loud”

The states and conditions for those states are described in a XML document. Once the condition(s) for one state is satisfied it moves on to the next and so on. The rate at which these sensors are polled have been manually assigned by the system designer. It was noted that manually setting these values is not optimal and a proposed algorithm was introduced that took into account how much power each sensor took. Based on the determined state only certain sensors will be pulled to achieve the most amount of context with the least amount of battery consumption.

About Frank Sposaro

Frank was the initial student to start the mobile lab with Dr. Tyson. After working on the first project, iFall, he and Dr. Tyson designed the Mobile Programming course as FSU. The course is used as a training base to recruit new students into the lab. His thesis researches several medical related applications, including iFall. Frank then went on to implement the redesign of the “favorite contacts” for Android’s Ice Cream Sandwich at Google HQ in Mountain View, California. He currently acts as a tech lead in the lab getting infrastructure and project management tools setup. He has special focus on native Android coding and UI design.