Acoustics researchers at the Georgia Institute of Technology (www.me.gatech.edu) have developed a piezoceramic actuator to eliminate brake squeals that occur when a vehicle slows down and the brake pads contact the rotor, setting up a vibration that manifests itself as a high-pitched noise. Mounted inside the brake piston, the actuator can suppress the vibration by applying bursts of a 20-kHz dithering frequency—above the human hearing range—to the backing plate of the inside brake pad. An open-loop control system that is connected to the brake-light switch, the actuator does not need any detector or logic system to determine the proper control frequency.
Oak Ridge National Laboratories (ORNL) is partnering with Local Motors to develop technology that will 3D-print an entire production-model car. A second deal with Cincinnati Inc. will develop a huge, very fast commercial 3D printer.