Facade: Auto-generating tactile interfaces to appliances

Digital keypads have proliferated on common appliances, from microwaves and refrigerators to printers and remote controls. For blind people, such interfaces are inaccessible. We conducted a formative study with 6 blind people which demonstrated a need for custom designs for tactile labels without dependence on sighted assistance. To address this need, we introduce Facade-A crowd-sourced fabrication pipeline to make physical interfaces accessible by adding a 3D printed augmentation of tactile buttons overlaying the original panel. Blind users capture a photo of an inaccessible interface with a standard marker for absolute measurements using perspective transformation. Then this image is sent to multiple crowd workers, who work in parallel to quickly label and describe elements of the interface. These labels are then used to generate 3D models for a layer of tactile and pressable buttons that fits over the original controls. Users can customize the shape and labels of the buttons using a web interface. Finally, a consumer-grade 3D printer fabricates the layer, which is then attached to the interface using adhesives. Such fabricated overlay is an inexpensive ($10) and more general solution to making physical interfaces accessible.