Recently, it has become common for designers to deal with complex and large-scale ubicomp or IoT spaces. Designers without technical implementation skills have difficulties in prototyping such spaces, especially in the early phases of design. We present miniStudio, a designers' tool for prototyping ubicomp space with proxemic interactions. It is built on designers' existing software and modeling materials (Photoshop, Lego, and paper). Interactions can be defined in Photoshop based on five spatial relations: location, distance, motion, orientation, and custom. Projection-based augmented reality was applied to miniatures in order to enable tangible interactions and dynamic representations. Hidden marker stickers and a camera-projector system enable the unobtrusive integration of digital images on the physical miniature. Through the user study with 12 designers and researchers in the ubicomp field, we found that miniStudio supported rapid prototyping of large and complex ideas with multiple connected components. Based on the tool development and the study, we discuss the implications for prototyping ubicomp environments in the early phase of the design.

Gesture-based interaction is still underutilized in the mobile context despite the large amount of attention it has been given. Using accelerometers that are widely available in mobile devices, we developed M.Gesture, a software system that supports accelerometer-based gesture authoring on single or multiple mobile devices. The development was based on a formative study that showed users' preferences for subtle, simple motions and synchronized, multi-device gestures. M.Gesture adopts an acceleration data space and interface components based on mass-spring analogy and combines the strengths of both demonstration-based and declarative approaches. Also, gesture declaration is done by specifying a mass-spring trajectory with planes in the acceleration space. For iterative gesture modification, multi-level feedbacks are provided as well. The results of evaluative studies have shown good usability and higher recognition performance than that of dynamic time warping for simple gesture authoring. Later, we discuss the benefits of applying a physical metaphor and hybrid approach.

Prototyping of gestural interactions in the early phase of design is one of the most challenging tasks for designers without advanced programming skills. Relating users' input from gesture-based sensor values requires a great deal of effort on the designer's part and disturbs their reflective and creative thinking. To deal with this problem, we present EventHurdle, a visual gesture-authoring tool to support designers' explorative prototyping. It supports remote gestures from a camera, handheld gestures with physical sensors, and touch gestures by utilizing touch screens. EventHurdle allows designers to visually define and modify gestures through interaction workspace and graphical markup language with hurdles. Because the created gestures can be integrated into a prototype as programming code and automatically recognized, designers do not need to pay attention in sensor-related implementation. Two user studies and a recognition test are reported to discuss the acceptance and implications of explorative prototyping tools for designers.