Surface I/O: Creating Devices with Functional Surface Geometry for Haptics and User Input

Surface I/O is a novel interface approach that functionalizes the exterior surface of devices to provide haptic and touch sensing without dedicated mechanical components. Achieving this requires a unique combination of surface features spanning the macro-scale (5cm ∼1mm), meso-scale (1mm ∼200μm), and micro-scale (<200μm). This approach simplifies interface creation, allowing designers to iterate on form geometry, haptic feeling, and sensing functionality without the limitations of mechanical mechanisms. We believe this can contribute to the concept of "invisible ubiquitous interactivity at scale", where the simplicity and easy implementation of the technique allows it to blend with objects around us. While we prototyped our designs using 3D printers and laser cutters, our technique is applicable to mass production methods, including injection molding and stamping, enabling passive goods with new levels of interactivity.