Kuo-cheng Hsieh won the 2007 Ig Nobel Economics Prize for patenting a device that catches bank robbers by dropping a net on them. But amid the glamour of the announcement, some of its charms may have gone unnoticed.
The invention is a nod to ancient methods of capturing animals in a forest, and also to the fanciful adaptation of those techniques in early cops-and-robbers movies. Hsieh's patent sums it up in a terse 94 words:
"A net trapping system for capturing a robber immediately is used in a place of business such as a bank. The device looks like a storing box and is installed above the entrance of the business. When a robbery takes place and the system is activated, an infrared detecting device determines if a robber is in a zone beneath the storing box. A net, a curtain, and a plurality of barriers will drop down immediately and simultaneously. After a lifting motor is activated, the system traps the robber and suspends him above the floor."
Prior to the Ig Nobel ceremony, we were unable to find Hsieh. Attempts to contact him by telephone, by letter, and even by visits to his home address in the city of Taichung, Taiwan, all failed. Fears arose that maybe the poor man had become trapped inside his own invention.
Happily, newspaper accounts of the ceremony reached him, and we have now learned, via journalists in Taiwan, that Hsieh runs a security company, that he is a former commander of an amphibian frogman unit, that he once set up similar traps underwater to capture swimming Chinese spies, and that he is diligently trying to market his machinery to banks.
Hsieh's patent has had at least one recorded effect: it inspired Zoltan Egeresi in the fight against terrorists.
Two years after New York and Washington were attacked by hijacked planes, Egeresi, a Californian inventor, filed a patent application for an "anti-hijacking system". In an ingenious commingling of ideas, Egeresi adapted the Hsieh bank-robber-trapping technology as a way to simplify a rather costly anti-hijacker system devised in the early 1970s by Gustano A Pizzo.
Pizzo's invention, described here last week, drops a hijacker through trapdoors, seals him into a package, then drops the encapsulated hijacker through the plane's bomb bay doors, whence he parachutes to earth.
Here is Egeresi's description of his simple, cheap, Pizzo-ian, Hsieh-ian hybrid invention:
"When one or more person [sic] is trying to overpower the pilots, this anti-hijacking system can provide a non-lethal last line of defence. Doors on the cockpit may not be penetration-proof. When pilot or flight attendant is confronted with a situation where the pilot's door is about to be penetrated, a concealed stainless steel net from below the carpet will hoist up all people to the ceiling."
· Marc Abrahams is editor of the bimonthly Annals of Improbable Research and organiser of the Ig Nobel Prize