Preparing Spatial Haptics for Interaction Design

Sammanfattning: Spatial haptics is a fascinating technology with which users can explore and modify3D computer graphics objects with the sense of touch, but its application potentialis often misunderstood. For a large group of application designers it is still unknown,and those who are aware of it often have either too high expectations of what is technicallyachievable or believe it is too complicated to consider at all. In addition, spatialhaptics is in its current form ill-suited to interaction design. This is partly because theproperties and use qualities cannot be experienced in an application prototype until asystem is fully implemented, which takes too much effort to be practical in most designsettings. In order to find a good match between a solution and a framing of aproblem, the designer needs to be able to mould/shape/form the technology into a solution,but also to re-frame the problem and question initial conceptual designs as shelearns more about what the technology affords. Both of these activities require a goodunderstanding of the design opportunities of this technology.In this thesis I present a new way of working with spatial haptic interaction design.Studying the serially linked mechanism from a well-known haptic device, and a forcereflectingcarving algorithm in particular, I show how to turn these technologies froman esoteric engineering form into a form ready for interaction design. The work isgrounded in a real application: an oral surgery simulator named Kobra that has beendeveloped over the course of seven years within our research group. Its design hasgone through an evolutionary process with iterative design and hundreds of encounterswith the audience; surgeon-teachers as users and potential customers. Some ideas, e.g.gestalting authentic patient cases, have as a result received increased attention by thedesign team, while other ideas, e.g. automatic assessment, have faded away.Simulation is an idea that leads to ideals of realism; that e.g. simulated instrumentsshould behave as in reality, e.g. a simulated dental instrument for prying teeth is expectedto behave according to the laws of physics and give force and torque feedback.If it does not, it is a bad simulation. In the present work it is shown how some of therealism ideal is unnecessary for creating meaningful learning applications and can actuallyeven be counter-productive, since it may limit the exploration of creative designsolutions. This result is a shift in perspective from working towards constantly improvingtechnological components, to finding and making use of the qualities of modern,but not necessarily absolute cutting-edge, haptic technology.To be able to work creatively with a haptic system as a design resource we needto learn its material qualities and how - through changing essential properties - meaningfulexperiential qualities can be modulated and tuned. This requires novel tools andworkflows that enable designers to explore the creative design space, create interactionsketches and tune the design to cater for the user experience. In essence, this thesisshows how one instance of spatial haptics can be turned from an esoteric technologyinto a design material, and how that can be used, and formed, with novel tools throughthe interaction design of a purposeful product in the domain of dental education.