【正文】 on the wall technology,‖ said Tim Reissman, a mechanical engineer at Cornell. ―Currently, our fly is this relatively huge insect,‖ he added, emphasizing the need for both smaller insects and lighter devices before the cybs will be of any help to the armed forces. VandenBrooks, coauthor of the Berkeley study, agreed: ―Some people definitely blow it out of proportion. We’re not even close to having any applications of that kind.‖ 104 ?Perhaps the greatest hurdle to a practical military application of bionic bugs is the issue of power. Any cyb electronics will require a power source, which usually means heavy batteries that weigh down even large insects like flower beetles and hawkmoths. Imagine a giant bug the size of your hand, lugging a backpack of batteries and microchips, trying to discreetly carry out its reconnaissance. Not exactly inconspicuous . But some researchers are determined to resolve the issues of power and size. ?reconnaissance [美 ][r??kɑn?s?ns, z?ns] . ? inconspicuous [美 ][??nk?n?sp?kju?s] 105 ? With the guidance of lab director Ephrahim Garcia, a mechanical and aerospace engineer, Reissman and others at Cornell have tried to create electronic devices powered by the moths’ own movements — an attempt to circumvent the dependency on cumbersome batteries. ? To acplish this, they use piezoelectric material, which turns motion ―into a voltage that can be utilized to power other things,‖ Garcia explained. Attaching a piezoelectric device to a moth turns the vibrations of its body during flight into a power source. The ultimate goal is functional batteryfree sensors, such as a tiny camera or ―a simple GPS monitor — the world’s smallest,‖ Garcia said. 106 ? Reissman is optimistic about their success. His colleagues are working to build miniature mechanical systems patible with the low voltages harvested from a moth’s movements. According to Reissman, their devices are almost efficient enough for takeoff. ? Not everyone thinks it’s feasible to extract sufficient energy from insect movement to power any mechanical instruments of practical use. ―I’m skeptical,‖ said Reid Harrison, a University of Utah bioengineer who builds electronic backpacks for locusts in order to study how their nervous systems help them escape predators. ―These animals only generate so much mechanical force. Even using piezoelectric material, it’s a very difficult challenge.‖ 107 ?Despite the obstacles to true energy harvesting, researchers persist. At the University of Washington, Brian Otis is designing a batteryfree inflight monitoring device for hawkmoths. ―There is data for insects showing huge differences in temperature between rest and movement,‖ he explained. Otis believes the high internal heat of a flying insect is another potential power source. 108 ? Because DARPA provides the funding, scientists who take on the challenge of creating insect cybs are ostensibly working toward the ultimate service of the government and army. But so far, the synthesis of insect and machine has benefited science more than the military. Insect cybs are not only pushing engineers to build devices — like Cornell’s GPS system — that are smaller, lighter and more efficient than anything they’ve made before, they could give scientists access to entirely novel information. 109 ?It’s very difficult to measure a living anism’s internal processes without somehow restraining it and disturbing its natural behaviors. But the more scientists learn about safely fusing living animals and technology, the better they bee at monitoring the many important biological processes that happen inside those animals, without keeping them caged up or tethered in labs. ? Bionic bugs could soon provide biologists with an unprecedented ability