Affective engineering involves measuring people’s affective responses to products, identifying the features of the product to which people are responding, and then using the information to improve the design of the product. By affective response, we mean the way they feel about the product. This involves two activities. First, accurate measurements of people’s affective engagement with products need to be measured and, second, the physical properties of the product and the mechanics of the interaction need to be characterised.
First activity at Leeds in 2001 started from comments by industrial collaborators in the manufacturing arena that although efficient and high quality manufacture was certainly necessary, ensuring that manufactured products would be what people wanted to buy (in preference to competitors’ products with the same functionality and usability) was becoming the bottleneck in new product introduction processes. Traditionally this was the area of industrial design, but perhaps a more systematic, engineering, approach would lead to an increased number of successful products. An engineering approach to subjective human-product interaction studies had been pioneered in Japan, starting from the 1970s. It is known there as kansei engineering.
Affective engineering is a Western interpretation of Kansei engineering which has been pioneered by Nagamachi at Hiroshima University since the 1970s. At Leeds, we have been applying the principles of affective engineering to the tactile properties of product packaging, personal care and domestic cleaning products, and to touch-sensitive display screens.
Our industrial collaborators include: Nokia, Mars, Cadbury, Boots, P&G, Logitech, SSL International and Fundermax.
The focus of our research includes the following areas:
Combination of visual and tactile cues
Our research will determine how different tactile cues are combined by the toucher, and how being able to see something affects tactile perception. We are investigating how stickiness and roughness affect the perception of softness, and how being able to see what is being touched with a laparoscopic tool affects someone’s perception of its softness. We are applying our findings to tactile displays for laparoscopic surgery and to applications in the digital economy. Modelling of the human finger has enabled us to better understand the mechanisms of human touch.
Quantitative methods for measuring affective response
We have developed new techniques for analysing the results of studies in the consumer evaluation of products. The approach, which uses the Rasch probabilistic model rather than statistics, and which is similar to item response theory, allows the construction of psychometric instruments that produce linear scales, need only small samples for reliability, and allow the outcomes of different experiments to be accurately compared.
Electrostatic tactile stimulation
The mechanics of electrostatic tactile stimulation are being studied which may eventually enable surface topographies to be simulated on the flat touch screens of telephone and tablets.
Prototyping of surface textures
This work has developed a process with which to design and manufacture bespoke surface textures which evoke particular affective responses.