MIT News  May 26, 2021 Technologies that sense the subterranean from above provide only a hazy view of submerged objects. Researchers at MIT have designed Digger Finger to meet the challenge of identifying buried objects. The Digger Finger is a slender cylinder with a beveled tip and uses a combination of blue LEDs and colored fluorescent paint. Its tactile sensing membrane is about 2 square centimeters. They ran its vibrating motor at different operating voltages, which changes the amplitude and frequency of the vibrations. They found that rapid vibrations helped “fluidize” the media, clearing jams and allowing for deeper burrowing. […]