Integrating hardware and software

For digital products, the relationship between the hardware and the software is important but their integration is largely achieved in the later phase of the design process. This paper presents new prototyping methods that allow digital product designers to effectively integrate the hardware and the software of the products from the early phase of the design process. The integration is accomplished by accurately overlaying a virtual display onto a quickly made functional hardware prototype using two augmented reality techniques; 1) using a video see through HMD and 2) using video projection. The results of the preliminary evaluation suggest that the early integrated prototypes are effective for design development and user studies.