Input Methods for Notification Systems: A design analysis technique with a focus on input for dual-task situations

Design and evaluation of input methods for secondary tasks in dual-task systems presents specific challenges not covered by traditional human-computer interaction design techniques. Emerging trends in the fields of mobile, ubiquitous, and in-vehicle information systems demonstrate a desire for users to interact with information systems while engaging in other tasks. Research on interaction within these various fields has revealed input methods that perform well for a particular task. However, few focus on the tradeoffs of attention that must be made to react to this notification information. A design analysis technique for input methods is proposed focusing on the design objectives of interruption, reaction, and comprehension for the secondary task made at the cost of primary task attention. Through a study conducted using a reusable usability test platform constructed for this thesis, a typical in-vehicle information system is analyzed using the proposed design analysis. Three input methods were designed and compared: a graffiti character recognizer, a touch screen, and a remote control for their proficiency at selecting an item from a list while operating a driving simulator. The results of the study revealed similar task performance between the varied input methods; however, the design analysis enabled recommendations about future design directions, confirming the viability of the technique for notification systems research.