Emotional design for smart product-service system: A case study on smart beds

Smart products typically have a strong sense of technology but rarely consider factors related to emotional design, thus keeping users at a distance. Human-centric emotional design can enhance the stickiness of products and maximize product use. To include emotional factors in the design of smart products, this paper constructed a top-down development method for smart product-service systems (PSS). First, we proposed an expanding three-level theory of emotional design (ETTED) to construct a user requirement framework. ETTED expands the connotation and extension of the three-level theory of emotional design (TTED) and can guide emotional design in detail. Second, the analytic hierarchy process (AHP) and fuzzy comprehensive evaluation (FCE) were proposed to perform a quantitative calculation on fine-grained requirements to distinguish the influence of each requirement in design practice. Finally, a smart bed with emotional factors was designed according to the requirements and their weights. To evaluate this development method with regard to mitigating the lack of emotional factors used to design Smart PSS, an eye-tracking experiment on the design of smart beds was conducted to verify the requirement framework based on ETTED and the requirement measurement method based on AHP and FCE. The eye-tracking data included participants’ pupil dilation and other physiological indicators of eye movements, which showed that the smart bed designed based on the development method for Smart PSS was more attractive than other similar products on Amazon. The method proposed in this paper is a top-down, quantitative and objective method that mitigates the lack of emotional factors considered in smart products design. Thus, the proposed method can be used as a systematic development method with Smart PSS.