Determining Voice Strategies for Hands-Free Human-Computer Interaction

Abstract

This Practitioner Paper examines a cost effective and efficient method to determine voice command strategies for hands-free controls when interacting with computer systems. Specifically, this method is applied to determining the combined use of voice commands and a head-tracking device as an alternative user interface for accessing digitized aircraft technical manuals. Aircraft maintainers from the Springfield, OH Air National Guard F-16 facility and the 445^th C-141 Air Force Reserve Unit served as subjects. User strategies appeared to follow on-screen interface characteristics and the user's experience level with computers. Generally, unlabeled icons and buttons elicited a point-and-click strategy, while labeled links elicited voice-only commands. Users with increased familiarity with Windows-based interfaces were prone to a point-and-click strategy, while novices were likely to attempt various function oriented voice commands. Due to the observed user strategies, several issues were identified and a series of recommendations are presented which address the strategic application of a voice command vocabulary to a hands-free user interface.