US engineers develop a large, high-speed 3D printer

WASHINGTON- The U.S. engineers developed a large, high-speed 3D printer that can print an object the size of an adult human in just a couple of hours.

The study published on Thursday in the journal Science online described the prototype 3D-printing technology called High-area Rapid Printing (HARP) that can safely print both hard, durable parts and elastic, bouncy objects.

Some 3D printers on the market can rival HARP’s speed, but they are limited in print-bed size and can only print small parts, often one at a time, according to the study.

The printer is about four meters tall with a 0.23-square-meter print bed. It prints vertically and can print about 0.46 meters in height in an hour, meaning it can print single, large parts or many different small parts at once.

“If we could print fast without limitations on materials and size, we could revolutionize manufacturing. HARP is poised to do that,” said Chad Mirkin with Northwestern University. It uses ultraviolet light to cure the liquid resins into hardened objects, and the process can print pieces that are hard, elastic or even ceramic, according to the study.

Unlike those laminated structures produced by common 3D printers, its printed parts are mechanically robust so that they can be used as parts for cars, airplanes and dentistry.

Resin-based 3D printer usually generates a lot of heat when running at fast speeds, which can deform the printed parts. To tackle this problem, the researchers project light through a window from below to solidify resin on top of a vertically moving plate, and put a nonstick liquid over the window to remove heat and then circulates it through a cooling unit. Also, the 3D printer doesn’t have to reduce resolution to print larger pieces, and it uses high-resolution light-patterning to achieve ready-to-use parts without extensive post-processing.

China launches new communication technology experiment satellite

XICHANG - China sent a new communication technology experiment satellite into planned orbit from the Xichang Satellite Launch Center in southwest China’s Sichuan Province late Thursday.

The satellite, launched by a Long March-3B carrier rocket at 23:21 (Beijing Time), will be mainly used for multi-band and high-speed communication technology experiments.

The satellite and the carrier rocket were respectively developed by the China Academy of Space Technology and the China Academy of Launch Vehicle Technology under the China Aerospace Science and Technology Corporation.

Thursday’s launch was the 315th mission of the Long March rocket series.