Analysis of the impact of slight changes in product formal attributes on user's emotions and configuration of an emotional space for successful design

Despite virtual concept testing being widely used to evaluate users' emotions elicited by products, prototypes tested in the early stages often undergo slight modifications before reaching the market. This study analyses how slight changes might affect users' perception as well as influence their intention to purchase a product. Furthermore, this analysis opens the door to a new way of dealing with the users' perceptual judgements by means of what has been defined as an emotional space for successful design (ESSD). This space integrates the users' emotional reactions into a physical product solution space. Using a loudspeaker as a case study, eight virtual prototypes were obtained by slightly varying height, diameter and colour. The prototypes were then evaluated by 225 users employing the semantic differential method. The results showed that modifying certain attributes significantly influenced users' responses, thus calling into question the consistency of the user's appraisal of virtual product concepts in the early stages of design. As such, the ESSD aids the identification of a subset of successful design solutions, so providing a clearly useful tool enabling designers to manage the users' emotional needs throughout the product development process.