Analysis of user activity in an engineering design task during the evaluation of an immersive stereoscopic design system

This paper describes the analysis of user activity during the evaluation of Co-Star, a demonstration immersive stereoscopic design system for cable harness design. During the study ten participants independently completed a sequence of three harness design tasks using the test system. All user interaction was recorded during each of the sessions and subsequently analysed to profile the distribution of user activity into five major activity classes: Design, System Operation, Navigation and Information, and Process Integration. The Design class was further sub-divided into Goal, Support, and Edit activities to produce a more detailed breakdown of this core activity. In addition measures of 'unproductive activity' and 'sequence breaks' (idle time) were used to identify relative performance within the different activities. The results clearly show the distribution of user activity for this task based on time and number of sequences of user activity and provide a compelling visualisation of this profile, with Navigation typically accounting for 41% and System Operation 23% of user activity whilst Design achieved 27%, in addition it was found that 7% of all activity was found to be unproductive, and 28% of system time was idle. Opportunities to improve operational design performance through targeted system developments can be clearly identified from these results. Copyright © 2006 by ASME.