Perceptual Information for User-Product Interaction: Using Vacuum Cleaner as Example

Product functions have become more complex as technology progresses. Often times the design of the product interface is not intuitive. For product design, designers provide products with an innovative form, and even more importantly curtails the gap between users and a product in operation. Clearly, user-friendly products are preferable to those that are not (Courage & Baxter, 2005). Product designers need to deal carefully with possible interaction problems between users and product interfaces. Furthermore, Dix, Finlay, Abowd and Beale (2004) stated that a person’s interaction with the outside world occurs through the exchange of information. Today, an important concern for designers is how product design can convey information to better help users understand product functions. In general, users interact with products through an interface. The controls, as well as the labels and signs, on the product hardware are part of the user interface (Hackos & Redish, 1998), which acts as a user-product information channel (Thimbleby, 1990; Baumann & Thomas, 2001). While designing user interfaces, designers may employ some techniques, such as affordance or signs, as cues for operations. The term affordance, which was coined by Gibson (1979), describes an intrinsically behavioural relationship between users and objects (You & Chen, 2006) and refers to the function or usefulness of an object (Vihma, 1995; Reed, 1988; Hartson, 2000; Galvao & Sato, 2005). As Norman (1990) stated, affordance provides strong cues to the operations of objects. For example, just by looking at them, users know that plates can be pushed using hands, and knobs can be turned with fingers. Furthermore, the affordance of an object can be specified by perceptual information (Reed, 1988; Gaver, 1991; McGrenere & Ho, 2000). Thus, the physical features are the information that relays the possible behaviours to users. In addition to physical properties, signs, icons, indexes, texts, and such, are used to illustrate the functions and operations of a product. As with signs, icons need to be represented in an appropriate form to facilitate the perception and recognition of its underlying meaning (Rogers & Sharp, 2002). Well-designed icons can help users to act quickly and confidently, because their meanings are immediately recognized (Horton, 1994). Some products have displays that show their functions and statuses with graphical icons and/ or texts. Typographies and images are created by designers to