Blowhole: Blowing-Activated Tags for Interactive 3D-Printed Models

Interactive 3D models have the potential to enhance accessibility and education, but can be complex and time-consuming to produce. We present Blowhole, a technique for embedding blowing-activated tags into 3D-printed models to add interactivity. Requiring no special printing techniques, components, or assembly and working on consumer-level 3D printers, Blowhole adds acoustically resonant cavities to the interior of a model with unobtrusive openings at the surface of the object. A gentle blow into a hole produces a unique sound that identifies the hole, allowing a computer to provide associated content. We describe the theory behind Blowhole, characterize the performance of different cavity parameters, and describe our implementation, including easy-to-use software to automatically embed blowholes into preexisting models. We illustrate Blowhole's potential with multiple working examples.