Innovative Developments in Design and Manufacturing

During product development, usability tests allow the investigation of product performance in terms of effectiveness and user satisfaction. Virtual Reality (VR) systems provide new modes of Human-Computer Interaction (HCI) that can support usability testing at the early design stages by adopting virtual prototypes to simulate product experience. The problem is that only posture and occlusion parameters can be easily measured while the emotional and affective dimension is difficult to be assessed. In this context, the present paper focuses on two objectives. Firstly, it aims at investigating which product attributes stimulate affective user response by defining a structured protocol to analyze how sample users experience product attributes determining affordance and synaesthesia qualities. Then, real and virtual environments are compared in order to address VR systems improvements. Consequently, the second goal is to define a new VR-based environment for usability testing by considering a proper set of existing technologies integrated with a proposed multi-sensorial system for materials texture and roughness perception. Protocol experimentations are carried out in household appliances. als and shapes. Touch instantly speaks to the visceral and reflective stages of human perception, stimulating emotional feelings and triggering cognition. However, the virtual simulation of tactile perception is not a trivial task for some technological limitations of available VR-based systems. In this context, the present research work proposes a structured approach to identify new scenarios for future user centered design environments for usability testing. The starting point is the definition of a protocol to analyze how sample users experience product attributes both on physical and virtual prototypes. This allows determining which product attributes stimulate users response. A QFD-based method is adopted to correlate users demands and product attributes in terms of materials, shape and composition. The analysis of users’ behavior during usability testing in different experimental set-ups represents a step forward the determination of the optimal VR system able to reduce the gap between virtual and real. Experimental tests highlight the importance of tactile feedback as crucial for product experience on virtual prototypes. Limitations of available systems and protocol results allow defining a roadmap for the creation of an integrated platform to support the multimodal interaction with virtual prototypes. The paper, after a description of related research work, describes in section 3 the developed protocol for analyzing the usability test process. Experimentations are carried out in the household appliances. Results are used as base in order to define the architecture of the new multi-sensorial VR-based system (section 4) for usability testing. Finally, in section 5, conclusions and future developments are reported.