Over the past decade, our group has approached interaction design from an industrial design point of view. In doing so, we focus on a branch of design called formgiving 1 .Traditionally, formgiving has been concerned with such aspects of objects as form, colour, texture and material. In the context of interaction design, we have come to see formgiving as the way in which objects appeal to our senses and motor skills. In this paper we first describe our approach to interaction design of electronic products. We start with how we have been first inspired and then disappointed by the Gibsonian perception movement [1], how we have come to see both appearance and actions as carriers of meaning, and how we see usability and aesthetics as inextricably linked. We then show a number of interaction concepts for consumer electronics with both our initial thinking and what we learnt from them. Finally, we discuss the relevance of all this for tangible interaction. We argue that in addition to a data-centred view it is also possible to take a perceptual-motor centred view on tangible interaction. In this view it is the rich opportunities for differentiation in appearance and action possibilities that make physical objects open up new avenues to meaning and aesthetics in interaction design.Keywords tangible interaction, industrial design, ecological psychology, semantics 1 Approach Background and InfluencesNow that micro-controllers have found their way into almost every household product, be it cookers, washing machines, cameras or audio equipment, a domain which once was considered pure industrial design is faced with many interaction design challenges. For modern-day industrial designers, getting a grip on these interaction problems appears to have become an essential part of their profession. Yet the last two decades or so show that this integration of interaction design and industrial design is far from trivial. Many interfaces of electronic products feel 'stuck on' (Figure 1).This is not only a matter of form integration, but also a matter of how 'display and push button' interfaces disrupt interaction flow, causing many electronic products to feel computeresque [2][3]. One would expect that 'strong specific' devices tailored to a single task would feature alternative interfaces that are superior to the 'weak general' PC which needs to cater for many tasks [4][5], However, most electronic products actually feel very PC-like in interaction style-complete with decision trees and menu structures-only worse, because of their lack of Tom Djajadiningrat Faculty of Industrial Design, Designed Intelligence Group Eindhoven University of Technology Den Dolech 2, 5600MB Eindhoven, The Netherlands E-mail: j.p.djajadiningrat@tue.nl 1. Whilst formgiving is somewhat of a neologism in English, many other European languages do have a separate word for form-related design, including German (Gestaltung), Danish (formgivnin), Swedish (formgivning) and Dutch (vormgeving).

In this paper, we articulate the role of movement within a perceptual-motor view of tangible interaction. We argue that the history of human-product interaction design has exhibited an increasing neglect of the intrinsic importance of movement. On one hand, human-product interaction design has shown little appreciation in practice of the centrality of our bodily engagement in the world. This has resulted in technologies that continue to place demands on our cognitive abilities, and deny us the opportunity of building bodily skill. On the other hand, the potential for movement in products to be a meaningful component of our interaction with them has also been ignored. Both of these directions (design for bodily engagement and the expressiveness of product movements) are sketched out, paying particular respect for their potential to impact both interaction aesthetics and usability. We illustrate a number of these ideas with examples.

No abstract

We present a skeletal linked model of the human hand that has natural motion. We show how this can be achieved by introducing a new biology-based joint axis that simulates natural joint motion and a set of constraints that reduce an estimated 150 possible motions to twelve. The model is based on observation and literature. To facilitate testing and evaluation, we present a simple low polygon count skin that can stretch and bulge. To evaluate we first introduce a hand-motion taxonomy in a twodimensional parameter space based on tasks that are evolutionary linked to the environment. Second, we discuss and test the model. The appendix shows motion sequences of the model and the real hand. Animations can be fetched from our website.