Informing the Use of Visual Assets in Industrial Augmented Reality

Augmented Reality is considered one of the most promising technologies for Industry 4.0. Augmented Reality allows to display the needed information at the right time and to locate it in the desired space, superimposing it to the real world. In this way, it could simplify the work of industrial operators in a variety of tasks, from planning and commissioning to assembly and maintenance. Despite the growing research interest and efforts for the development of Augmented Reality applications and technologies for the industrial domain, Augmented Reality is still rarely used in real industrial procedures, often remaining at a conceptual level. In fact, developers fail to completely answer the actual needs of industries and workers because of a lack of knowledge of the context and the absence of guidelines to drive the design and development of Augmented Reality applications. One of the open issues is the choice of the proper visualization methods to display technical information in Augmented Reality, which is not trivial. Both the paper-based documentation, based on text and illustrations, and digital documentation, including CAD models and image or video-based tutorials, present different criticalities when adapted to the Augmented Reality technology. Other visual material has been developed specifically to be used in Augmented Reality, but it is difficult to use because of a lack of standards which are instead present for the former paperbased and digital documentation. In this work, we categorize and compare different Augmented Reality visual assets, illustrating their advantages and disadvantages and providing directions for future research.