Shrinking Hardware, Expanding Interfaces

3D Sensing with MEMS Accurately sensing location in 3D currently requires large, expensive devices. Researchers in MIT’s Department of Aeronautics and Astronautics have devised an approach to microelectromechanical systems (MEMS) fabrication that lets engineers design 3D configurations for existing fabrication processes. They used the approach successfully to build a MEMS device that enables 3D sensing on a single chip. The silicon device, about the size of Abraham Lincoln’s ear on a US penny, contains microscopic elements about the width of a red blood cell that can be engineered to heights hundreds of microns above the chip’s surface. Postdoc Fabio Fachin says that sensors can be placed atop and underneath the chip’s minuscule bridges to enable 3D sensing and actuation—for example, detecting 3D phenomena such as acceleration. Such compact accelerometers have applications—for example, space navigation—that require extremely accurate resolution of 3D acceleration fields in a small form factor. For more information, see www.rdmag.com/ news/2012/02/researchers-develop-new-approachproducing-3d-microchips.