Temporal Form in Interaction Design

IntroductionInteraction design is distinguished from most other design disciplines through its temporal form. Temporal form is the computational structure that enables and demands a temporal expression in the resulting design. When programming computers we create a temporal form that then comes to expression through an output of actuators and other materials. Indeed, it is these material manifestations of temporal forms that enable our interactions with computational things, as digital computations in themselves are inaccessible. Thus, temporal form gives interaction design a kinship with temporal arts like music, dance, and film. While several interaction design researchers have already articulated this aspect, we have still to grasp the details of what it entails (cf. Hallnas & Redstrom, 2001; Hallnas & Redstrom, 2006; Maze & Redstrom, 2005; Vallgarda, 2014). How do we experience temporal form in computational things? What significance does the temporal form hold for the overall experience? What is the relation between temporal form and the other form-elements in interaction design? What relations can we find between the expressions of computational things and our experience of them when it comes to temporal forms? Temporal form is what enables poetry. In music, temporal form is the composition of tones, pauses, and timbre, arranged into harmonies and rhythms. In movies, it is the composition of actions and backgrounds moving stories forward. In poetry, it is the composition of meanings and rhythms. Temporal form holds functional as well as aesthetic power in the composition of the overall design--just as physical form does. The traditional view on temporal form in relation to computational things has been that of speed. It has been a matter of removing delays from hardware and software to enable instantaneous representation on graphical displays; it has been about speeding up computations to achieve faster results, etc. Certainly, the execution speed in a computational thing is important and will affect what we do with it, but there are more aspects of temporal form to be explored than speed. Material and tangible computing have changed what forms of interaction we design for and the materials we use. They have entailed that the contexts in which we use computational things have multiplied and that not all of those contexts are suited for speed as the only temporal expression. Indeed, it has become crucial to pay attention to the underexplored notions of timbre and pauses as well as the relations between materials and state changes. From what can we design our rhythms and harmonies? Vallgarda (2014) has proposed to see temporal form as part of a trinity of forms that would constitute the form-giving concerns in the practice of interaction design, with the other forms being physical form and interaction gestalt. We have long understood physical form and its relation to materials. In industrial design schools, for instance, students are taught how any physical form can be broken down into cubes and cylinders, and that every other form comes out of the transitions between them (cf. Itten, 1975; Ching, 2010). We know about materials and their influence on form and expression (cf. Manzini, 1989), and we know about style of physical objects (cf. Semper, 2004). We also have an understanding of the interaction gestalt where concepts like affordances (Gibson, 1986) or signifiers (Norman, 2011) help us understand how physical form is linked to the interaction gestalt. Additionally, Dourish (2001) has succeeded in establishing all interaction as social as well as embodied. Indeed, what we lack most is an understanding of temporal form's role in all this.In the first part of this paper we underline the importance of working explicitly with temporal form in the design of computational things. We give a nuanced account of what temporal form is in interaction design. We then look at related work synthesizing what we already know of the temporal concerns in interaction design and human-computer interaction (HCI). …