An interactive "retrographic sensor" for touch, texture, and shape

Retrographic sensing is a novel method for measuring surface texture and shape. It uses a sensor made of clear elastomer with a painted skin to non-destructively change an object's reflectance characteristics. When an object is pressed into the sensor, the painted skin conforms to the shape of the object. Viewed from behind, the object appears as a shaded surface and the shape of the surface can be estimated using photometric stereo techniques. In previous work [Johnson and Adelson 2009], we describe a method for reconstructing high-resolution 2.5D surface data from a single image of the sensor. In this work, we demonstrate an implementation of the system that runs at interactive rates.