Mixed Prototyping For Products Usability Evaluation

Mixed prototyping is an industrial practice that combines virtual and real components in order to realize a prototype of a product used to evaluate and assess the design choices. Recently, mixed prototypes have been also used to assess the usability of products interface. This particular application arises several problems related to the devices and the interaction techniques that, better than others, allow a natural interaction with the mixed prototype.This paper presents a mixed reality environment for usability evaluation that deals with two specific problems of this kind of application: the occlusion between real and virtual objects and the interpretation of the user's gestures while he/she is interacting with the elements of the product interface. In particular we propose a technique able to manage both the problems by using only commodity hardware and video processing algorithms, thus avoiding the use of expensive data-gloves and tracking devices.The proposed approach has been validated through a user study addressed to establish whether and to what extent the augmented reality devices and the techniques proposed may distort the usability assessment of the product. Moreover, the user study compares the mixed reality environment adopted in this study with a classical virtual reality set-up.