大学英语综合教程 第四册 Unit 2B

[00:00.00]Steve Shladover outlines the benefits to be gained from vehicles that could drive themselves
[00:06.71]and discusses how this could be achieved.
[00:10.61]INTELLIGENT VEHICLES                                            by Steve Shladover
[00:15.33]Even when cars were still young,futurists began thinking about vehicles that could drive themselves,without human help
[00:24.79]Perhaps the best known of these conjectures was the General Motors Futurama,the hit of the1939 New York World's Fair
[00:35.40]Now,at the start of the new century,it's worth taking a fresh look at this concept and asking
[00:42.92]how automation mingt change transportation and the quality of our lives.
[00:49.50]Consider some of the implications of cars that could drive themselves.
[00:54.83]We might eliminate the more than ninety percent of traffic crashes
[01:05.02]that are caused by human errors such as misjudgments and inattention.
[01:10.92]We might reduce antisocial driving behavior such as road rage,thereby singnificantly reducing the stress of driving.
[01:20.61]The entire population,including the young,the old,and the infirm,
[01:26.70]might enjoy a higher level of mobility without requiring advanced driving skills.
[01:33.91]The luxury of being chauffeured to your destination might be enjoyed by all,not just the wealthiest individuals.
[01:42.82]Fuel consumption and pollution might be reduced by smoothing traffic flow
[01:49.45]and running vehicles close enough to each other to benefit from aerodynamicdrafting.
[01:56.48]Traffic-management decisions might be based on firm knowledge of vehicle responses to instructions,
[02:03.79]rather than on guesses about the choices that drivers might make.
[02:09.04]The capacity of a freeway lane might be doubled or tripled,making it possibe to accommodate growing demands for travel 
[02:18.00]without major new construction,or,equivalently,today's level of congestion mingt be reduced,enabling travelers to save time
[02:28.43]Is it feasible?
[02:30.96]This is now a realisitic prospect.With advances in technology
[02:36.00]we can readily visualize your trip on an automated highway system.
[02:41.67]Imagine leaving work at the end of the day and needing to drive only
[02:47.05]as far as the nearest on-ramp to the local automated highway.At the onramp,
[02:54.94]you press a button on your dashboard to select the off-ramp closest to your home and then relax
[03:02.94]as your car's electronic systems,in cooperation with roadside electronics and similar systems on other cars,
[03:11.76]guide your car smoothly,safely,and effortless toward your destiantion.
[03:18.69]En route you save time by maintaining full speed even at rush-hour traffic volumes.
[03:25.82]At the end of the off-ramp you resume normal control and drive the remaining distance of your home
[03:32.90]better rested and less stressed than if you had driven the entire way.
[03:38.93]Although many different technical developments are necessary to turn this image into reality,none requires exotic technologies
[03:48.52]and all can be based on systems and components
[03:52.99]that are already being actively developed in the international motor vehicle industry.
[03:59.60]These could be viewed as replacements for the diverse functions that drivers perform every day:obserbving the road
[04:08.01]observing the preceding vehicles,steering,accelerating,braking,and deciding when and where to change course.
[04:16.78]Observing the road
[04:19.66]Researches have developed a road-reference and sensing system
[04:24.65]that makes it possible to determine accurately a vehicle's position and orientation relative to the lane's center.
[04:33.19]Cheap permanent magnets are buried at four-foot intervals along the lane centerline
[04:40.22]and detected by magnetometers mounted under the vehicle's bumpers.These meters prvide the information