Modeling Human-Computer Interaction in Smart Spaces: Existing and Emerging Techniques
Yngve Dahl · InTech eBooks · 2008
In this section we will briefly discuss how the presented modeling technique can contribute to inform design of ubiquitous computing and smart spaces. We will also point out some limitations. 6.1 Main Contributions De facto computer system modeling formalisms tend to remove physical features of the system that is modeled. This makes it difficult to use such approaches to guide thinking about design of smart spaces, in which digital services and real-world user actions and events merge. How users can provide computer input, properties of the devices and tools, and collocation between elements of interaction are not easily communicated through system models. This highlights need for physical models. In this essay, we have argued that one way to accommodate physical design aspects of smart spaces is to think visually. The proposed method has adopted features from narrative modeling techniques such as storyboarding. By describing interaction in smart spaces sequentially through snapshots or frames it offers a simple way for designers to "zoom" in or out on an interaction sequence by adding or removing frames. As illustrated in previous section this makes it possible to represent both high-level interaction patterns, as well as more specific use scenarios. By introducing a set of formal design elements the proposed modeling technique allows designers to create structured representations. This can help draw attention to the different roles design elements can play in interaction in smart spaces. Essentially, the design elements reflect the basic physical capabilities (mobility, immobility, portability) of the realworld entities they represent. The semantic relationship between the design elements reflects the most common methods of physical interaction (proximity, presence, and touch) supported by UbiComp technology. The examples provided in the previous section highlights that while the actual system operations (i.e. the functional specification) are likely to be constant, the composition of design elements that form the physical interface of smart spaces is highly flexible. Being able to describe such compositions in a structured way can make it easier for designers to recognize similarities and distinction between different interaction design solutions, and re-use or adjust previous models to new design problems. Results from a preliminary focus group evaluation (Dahl, 2007) also suggested that one of the key benefits of the formalism is that the generated models promote reflection and discussion among designers concerning how design solutions present themselves to users. 6.2 Limitations As with any modeling technique from computer-related disciplines there are also certain limitation associated with the approach we have presented and discussed. Firstly, it is limited to representing location-aware and token-based systems only. Alternative interaction techniques for smart spaces, however, include pointing and gesturing (Levin-Sagi et al., 2007), speech-based (Potamitis et al., 2003), and gaze-based interaction (Bonino et al., 2006). Formalizing these interaction techniques will require custom designed notations and semantics.