Assessment methods for comfort of consumer products at early stages of the development process

Design engineers who are involved in the early conceptual phase of the development of products such as seats, headphones and domestic appliances stress the increasing importance of comfort. Comfort is taken into account in the purchasing decisions of buying a chair, a bed, and when driving a car, or flying.

The terms comfort and discomfort are widely used in studies where prototypes are tested for comfort. Despite the frequent use of these terms there is an absence of a general notion of comfort or discomfort. There are three main issues when designing a product to achieve comfort: 1) the exact cause of comfort is unknown, 2) comfort relies to a certain extent on subjectivity and, 3) there is a lack of a methodology for considering comfort in the design process [Vink, 2005].

This thesis describes an investigation to gain an understanding of the nature of comfort in product design at the early stages of the design process and, to investigate the factors that influence the different dimensions of comfort (physical, physiological and psychological). The investigation has been conducted in strong collaboration with an industrial partner working with ear-worn devices, providing access to data, products and possibilities to test methods.

Three empirical studies were carried out within the industry of external-ear body worn products for commercial use. Key findings included the identification of associations between human dimensions and product dimensions by providing an extended matrix of human dimensions advancing the understanding of human geometry and product complexity.

The findings of this research also revealed that there are strong dependencies between comfort and the attractiveness towards the visual profile of a product. Positive attractiveness towards a product enhances the expectation and experience of comfort and vice versa. Additionally, archetype individuals were identified for the issuing of representative user panels to be used in the comfort studies conducted at the early conceptual phase of the design process.

From the findings, a methodological framework was developed summarizing all the applications of 2-dimensional and 3-dimensional data. In addition, a matrix of archetype persons was also generated with the aim to support designers in streamlining users for the creation of more reliable user panels for the execution of comfort studies to evaluate prototypes in terms of comfort.

The methods have been evaluated and implemented within the collaborating company of external- ear body worn products. The research has contributed towards understanding the multidimensionality of comfort and towards providing with methods to assess comfort at the early stages of conceptual development.