Performance differences between instructions on paper vs digital glasses for a simple assembly task

Providing instruction for assembly tasks is essential in modern manufacturing industry, as well as in households for customers that buy products to be assembled at home. Recent technological developments might be able to assist in completing an assembly task faster and more accurately. The aim of this study was to evaluate whether performance and usability differs when instructions for an assembly task are presented on digital glasses versus paper.

Participants (n = 63) completed one of three versions of an assembly task (between-subject-design) with LEGO® bricks: (1) with paper instruction (P), (2) with text instructions presented stepwise via digital glasses (GT), (3) with stepwise text and auditory instruction (in parallel) on digital glasses (GA). Outcome measures on performance were completion time and errors. Furthermore, usability was measured by the User Experience Questionnaire, the Standardized Usability Questionnaire, the Post-Study Usability Questionnaire, and cognitive processing skills were assessed by the Trail Making Test and different versions of the Eriksen Flanker Task. Analyses were adjusted for the confounding factors age, gender, experience with glasses and LEGO, and problems with instruction.

Findings indicate that task completion was faster with the paper instructions compared to both versions of instruction via digital glasses (GT, GA). We observed no difference in accuracy and usability between the instructions. "Novelty" was rated higher for instructions for both GT and GA, compared to P.

Results show that instructions on digital glasses may not always be more effective for assembly than the traditional paper-based instructions. Further studies are necessary to investigate whether effectiveness may depend on task complexity, target group, experience of the user with task and device, and how the information is presented.