Beer Blanket

Computing Gear

Three years ago, after a bash at his apartment, Adam Hunnell was stuck trying to figure out what to do with a keg full of warm beer. “If you don’t drink it all, it just gets ruined and you have to throw it out,” says 23-year-old Hunnell, a grad student in the physics department at Pennsylvania’s Case Western University. Not one to cry into his glass, though, the budding inventor drew up plans for a thermoelectric blanket that would keep kegs to a chilly 32 - 35 degrees F. In April 2004, he won $20,000 from the National Collegiate Inventors and Innovators Alliance to build the prototype.

The solid-state technology uses the Peltier effect, in which heat moves across two metal junctions when current flows through them. Hunnell’s wrap will house 8 - 10 semiconductor plates, most likely made from bismuth telluride. Used to cool laser equipment, the components create a heat flux in one direction. And there may be other benefits to the Peltier effect: while one side of the material gets cold, the other side gets proportionally warmer. Nachos anyone? —Bob Parks

Some prefer a nuts-and-bolts approach to computing — like Tim Robinson, who built a version of Charles Babbage’s Difference Engine No. 1 entirely out of Meccano parts. Babbage’s original invention, which he partially prototyped in 1832 but didn’t finish, proved that machines could generate polynomial solution tables. Meccano sets arrived later; the building toys hit it big in the 1920s and retain a worldwide following today, complete with regional building clubs, conventions, a mailing list, and the glossy magazine Constructor Quarterly.

Porting Meccano’s assortment of trusses and gears to decimal computation took ingenuity. Robinson devised his basic counters by meshing 95- tooth wheels against 57-tooth wheels. The resulting 5: 3 ratio means each small wheel-stop corresponds to a ¹⁄ 10 turn of the larger wheel. A rotating handle on top provides the power to Robinson’s Difference Engine #1, which cranks out new solutions, literally, about every four seconds. As Robinson suggests, had Babbage had Meccano, the history of computing might be very different. —Paul Spinrad

>>Keg Wrap: case.edu/news/2004/4-04/keg.htm

>>Meccano Computing Machinery: meccano.us

Photography by Michael Sands (Beer Blanket) and Tim Robinson (Computing Gear)

Make: 19