Does the Medium Matter? A Comparison of Augmented Reality Media in Instructing Novices to Perform Complex, Skill-Based Manual Tasks.

Past research comparing augmented reality (AR) media such as in-situ projection and head-mounted devices (HMD) has usually considered simple manual activities. It is unknown whether previously reported differences between different AR media also apply to complex, skill-driven tasks. In this paper, we explore the feasibility and challenges in designing AR instructions for expertise-driven, skilled activities. We present findings from a real-world, between-subjects experiment in which novices were instructed to trim and bone sub-primal cuts of pork using two interactive AR prototypes, one utilizing in-situ projection and a second using the Hololens 2. The prototypes and instructions were designed in consultation with experts. We compared novices' task performance and subjective perceptions and gathered experts' feedback. Although both users and experts indicated a subjective preference for in-situ projection, results indicate that when tasks require knowledge, skill and expertise, the choice of the AR medium itself may not be consequential. Rather, in our experiment, the instruction quality influenced comprehension, knowledge retention and task performance. Hence, from an engineering perspective, emphasis ought to be laid on gathering and structuring expert performance and knowledge to create effective instructions, which could be delivered using any AR medium suited to the task and work environment.