A challenge in commanding a robot arm to carve up a target object with its router is precise understanding of where that object is located in "three space." The team recently developed a process to locate the plane of its angle table (the baseline surface upon which an object rests) using a piezoelectric "button" that is tapped several times to establish at least three points in space. When tapped, the button under the router shaft lights up the indicator at the bottom right of the image. This close-up more clearly shows the piezoelectric button under the router shaft. Photos by Guillermo Gomez