Mixed prototypes for the evaluation of usability and user experience: simulating an interactive electronic device

Mixed prototyping technology can be used to represent and simulate the behavior of interactive products at low cost and with great flexibility. This preliminary experimental research intends to verify the suitability of using this technology in the evaluation of usability and user experience of interactive products. Users and experts evaluate the mixed prototype of an image projector with regard to its own usability, and also with respect to its ability to be used to evaluate usability and user experience aspects of the real projector. Users perform tasks on both the real projector and its mixed prototype. In regard to these comparative performance evaluations, time to perform the task and number of errors show a clear positive relationship with the difficulty of the task for both mixed prototype and real projector. In regard to more subjective UX evaluations, the results show to be congruent. However, we realize that emotions assigned to the mixed prototype are influenced by the “fascination” that augmented reality arises in individuals. Experts evaluate the mixed prototype with respect to aspects of the interaction with the product that it is able to simulate, and with respect to the classes of products best suited to be prototyped. They highlighted the possibility of using the technology to evaluate product performance, ergonomics, and operation. In regard to the classes of products to be prototyped, experts’ suggestions coincided with the classes of products that have already been used in research: household appliances, information and communication devices, and automotive parts and accessories.