Winged Robot Learns to Fly
　　Learning how to fly took nature millions of years of trial and error1 —but a winged robot has cracked2 it in only a few hours, using the same evolutionary principles. Krister Wolff and Peter Nordin of Chalmers University of Technology (CUT) in Gothenburg , Sweden, built a winged robot and set about3 testing whether it could learn to fly by itself, without any pre-programmed data on what flapping is or how to do it.
　　To begin with4, the robot just twitched and jerked erratically. But, gradually, it made movements that gained height. At first, it cheated—simply standing on its wing tips was one early short cut5. After three hours, however, the robot abandoned such methods in favor of6 a more effective flapping technique where it rotated its wings through 90 degrees and raised them before twisting them back to the horizontal and pushing down.
　　“This tells us that this kind of evolution is capable of7 coming up8 with flying motion,” says Peter Bentley, who works on evolutionary computing at University College London. But while9 the robot had worked out how best to produce lift10, it was not about to take off. “There’s only so much that evolution can do,” Bentley says. “This thing is never going to fly because the motors will never have the strength to do it,” he says.
　　The robot had metre-long wings made from balsa wood and covered with a light plastic film. Small motors on the robot let it move its wings forwards or backwards. up or down or twist them in either direction.
　　The team attached the robot to two vertical rods, so it could slide up and down. At the start of a test, the robot was suspended by an elastic band. A movement detector measured how much lift, if any11, the robot produced for any given movement. A computer program fed the robot random instructions12, at the rate of13 20 per second, to test its flapping abilities. Each instruction told the robot either to do nothing or to move the wings slightly in the various directions.
　　Feedback from the movement detector let the program work out which sets of instructions were best at producing lift. The most successful ones were paired up14 and “offspring” sets of instructions15 were generated by swapping instructions randomly between successful pairs. These next-generation instructions were then sent to the robot and evaluated before breeding a new generation, and the process was repeated.
　　词汇: flap /flAp/v.振翅;拍打，拍动 rotate /rEu5teit/v.旋转，转动 twitch /twitF/v.猛抽;抽动 balsa /5bRlsE/n.轻木 jerk /dVE:k/v.猛拉;急扭 offspring /5RfsprIN/n.后代;结果，产物 erratically /i5rAtik/adj.飘忽不定地;不稳定地 swop /swCp/v.交换;交流
　　注释：
　　1. Learning how to fly took nature millions of years of trial and error:自然界里的飞行学习用了几百万年的时间反复实践和磨炼。
　　2. crack: to break through (an obstacle) in order to win acceptance or acknowledgement: 突破(障碍)
　　3. set about:开始做，着手
　　4. To begin with: 首先
　　5. short cut: 捷径
　　6. in favor of:原意为“赞成;支持”。这里，…… the robot abandoned such methods in favor of a more effective flapping technique意为:……这个机器人放弃了这样的方法，而去使用一种更为有效的扇动翅膀的技术。
　　7. be capable of: [指物]有可能，可以……
　　8. come up: to manifest itself; arise 出现。
　　9. while:虽然，尽管
　　10. lift:升高
　　11. if any:若有的话。确切意思是 :如果它能升高的话。
　　12. ... fed the robot random instructions:给机器人输入随意设定的指令。 fed是feed的过去式。
　　13. at the rate of:以……的速度
　　14. pair up:把……配成一对
　　15.“offspring”sets of instructions:指的是将成功的指令配对后的结果。“ offspring”本来是后代的意思，在此修饰sets of instructions，所以加了双引号。练习:
　　1. Which of the following is NOT true of what is mentioned about the winged robot in the second paragraph? A The two professors of CUT built the winged robot B The two professors of CUT tested whether the winged robot could learn to fly. C The two professors of CUT programmed the data on how the robot flapped its wings. D The two professors of CUT tried to find out if the robot could fly by itself.
　　2. How did the robot behave at the beginning of the test?
　　A It rotated its wings through 90 degrees.
　　B It twitched but gradually gained height.
　　C It was twitched and broke down.
　　D It landed not long after the test.
　　3. Which of the following is nearest to Peter Bentley’s view on the winged robot? A The winged robot could never really fly. B The winged robot did not have a motor. C The winged robot should go through further evolution before it could fly. D The robot could fly if it were lighter.
　　4. What measured how much lift the robot produced? A Two vertical rods. B A movement detector. C An elastic band. D Both B and C.
　　5. What does “the process” appearing in the last paragraph refer to? A Pairing up successful inst ructions. B Sending instructions to the robot. C Generating new sets of instructions for evaluation. D All the above.
　　答案与题解 :
　　1. C A、B、D在第二段中都提到过。 C是错误的，因为文中说，教授们测试机器人是否会自己学会飞行，而且预先没有对翅膀扇动的方式进行数据设定。
　　2. B第三段描述了机器人如何学习飞行的过程。第一句和第二句是问题的答案。
　　3. A第四段主要是 Peter Bentley对飞行机器人的看法。他认为前文描述的进化过程只能使机器人有一些飞行的动作，而要让其起飞则永远不可能，因为不可能有如此大功率的发动机。所以 A是正确选项
　　4. B答案在第六段的第三句中。
　　5. D文章昀后一段具体描述在机器人的进化过程中，指令的进化过程。成功的指令配对后产生新一代的指令，将指令输入机辑人，经筛选再进行成功指令配对，再产生新一代指令，如此反复进行。所以 D是正确选项。