上月初，美国总统奥巴马提议未来十年拨款20亿美元，用来开发新能源汽车和卡车——这个主意对政客们来说一直很有诱惑力。历届总统和国会议员为了讨好选民，已经砸了不少银子研究油电混合动力、生物燃料、高级电池、燃料电池、太阳能等各种技术，但迄今为止都没有取得任何实质性的突破，95%的新车还是在用喝油的引擎。

    现在有了另外一个看来颇有希望的战略：投资开发自动和半自动驾驶系统。这类技术的主要功能是防止或纠正驾驶者的错误。由于能最大限度地减少碰撞，提高行车的安全性，未来的汽车可以设计得更轻，用料更省。汽车企业指出，重量变轻就意味着更省油。轻量化的汽车还能让电池的电力发挥更大作用，延长续航里程。

    截至目前，汽车厂商还没有请求政府帮助开发自动驾驶系统（但也没有拒绝华盛顿当局向它们提供研发补助）。自动驾驶系统这个议题至今还没有进入政治领域。通用汽车公司（GM）首席技术官乔恩•劳克纳表示：“就算自动驾驶技术不能让汽车驾驶完全自动化，它在减少交通事故上也有很大潜力。”

    劳克纳称，通用汽车旗下的凯迪拉克（Cadillac）将会在2020年前推出一项名为“超级巡航”的功能，使高速公路上行驶的司机不用手握方向盘。汽车会保持在车道中央行驶。如果前方出现车辆，或是有车辆超车到它前面，汽车就会自动减速或停止前进。

    通用表示，用“超级巡航”的驾驶者仍然必须注意路面情况——但他们也能安全地发短信，甚至将目光移开路面。大众汽车（Volkswagen）的奥迪（Audi）则表示很快会为它的旗舰A8装备“塞车辅助系统”，它能在低速行驶时保持正常行驶状态，同时避免撞车。

    可能还得过好几年——甚至好几十年，变道警示系统、车车通信、自适应巡航控制、先进视觉和刹车系统才能彻底演进为无人驾驶技术。很多工程师相信，一旦无人驾驶汽车大量上路，由驾驶者导致的事故数量将大幅下降，只有极端情况下才会发生事故。

    劳克纳说：“等到我们展示出这项技术的效果时，监管者可能就会考虑调整现行政策，让汽车企业从根本上改变汽车现有的设计方式，允许我们从汽车上减去大量部件。”

    Earlier this month, President Obama proposed spending $2 billion over the next decade to find an alternative to operating cars and trucks on oil -- an idea that has been catnip to the political class. Previous presidents and congresses have sought favor with voters by spending on gas-electric hybrids, biofuels, advanced batteries, fuel cells, solar, and other technologies. So far, no breakthrough has been made; gas-sipping engines still power more than 95% of new cars.

    There is another promising strategy: investing in autonomous and semi-autonomous systems. Such technology, which prevents or corrects driver error, could minimize collisions, making driving so safe that future vehicles will be built with far less weight and mass than today. Automakers point out that lighter weight automatically translates into less gasoline burned. Lighter vehicles also could make the power of batteries more useful and extend their range.

    Carmakers so far aren't asking for government help to develop autonomous systems. (Assistance from Washington in the form of subsidized research typically isn't refused.) The subject of autonomous systems so far hasn't reached the political arena. "Autonomous related technologies, even if they fall short of making a vehicle fully autonomous, hold the potential to reduce fatalities and injuries on our roadways," says Jon Lauckner, GM's (GM) chief technology officer.

    Lauckner said that GM's Cadillac division will offer a feature called "Super Cruise" before the end of the decade. Super Cruise will allow a driver at highway speeds to take his or her hands off the wheel. The car will remain centered in its lane, and slow down or stop for slower traffic ahead or if a car cuts in front of it.

    A driver using Super Cruise must pay attention to the road, GM says -- but he or she also can safely text or even take eyes off the road. Volkswagen's Audi division said it soon will equip its A8 flagship with "traffic jam assist" that steers and avoids collisions at low speeds on highways.

    It might take years -- or even decades -- for systems like lane-change warning, car-to-car communication, adaptive cruise control, advanced vision and braking to evolve into fully driverless technology. Once driverless cars are used in great number, many engineers believe, accidents that result from driver error will decline sharply, occurring only under extreme or unusual circumstances.

    "When we show this technology can have that effect," Lauckner says. "Regulators might consider adjusting the rules that would allow automakers to fundamentally change the way we design vehicles, allowing a significant amount of mass to be removed from cars."

    现在福特（Ford）推出的全新中级车Fusion重量为3,427磅，在城区道路上每加仑燃油可行驶22英里，高速公路上为34英里。而丰田（Toyota）的雅力士（Yaris）车重还不到2,300磅，城区道路上每加仑燃油可行驶30英里，高速公路上为37英里。

    换言之，为车减重1,000磅左右意味着每年燃油消耗可减少90加仑。由电池驱动的更小更轻的车辆将可以行驶更长的里程。可以预计，未来的中级车将不再需要现在所用的大量加强钢材，而正是这些钢材才能让车辆通过联邦政府的碰撞测试。轻量化的材料将取代钢材。汽车甚至不再需要用安全气囊或大量安全配置来保护乘客和司机遭遇事故时的安全。

    不过，汽车企业首先必须证明，自动和半自动驾驶系统——有时候也叫“辅助驾驶系统”——确实能显著降低事故率和伤亡率。目前，美国每年发生约35,000起各类事故。因此，只有“超级巡航”这类系统变得更普及时，才有可能达到这个效果。

    译者：清远

    Today's Ford (F) Fusion midsize sedan, which weighs 3,427 pounds, achieves fuel economy of 22 miles per gallon in the city, 34 miles per gallon on the highway. A Toyota (TM) Yaris, at just under 2,300 pounds, gets fuel economy of 30 miles per gallon in the city, 37 miles per gallon on the highway.

    In other words, reducing a car's weight by 1,000 pounds or so translates into almost 90 gallons less fuel burned annually. Smaller, lighter vehicles powered by batteries would feature longer range than today. Presumably, future midsize sedans wouldn't need much of the reinforcing steel that today helps a car pass federal crash tests. Lighter materials might replace steel. The vehicle wouldn't need airbags or much of the safety paraphernalia that keeps passengers and driver safe in the event of a collision.

    First, however, automakers must prove that autonomous and semi-autonomous systems -- sometimes called "assisted driving" -- can reduce drastically the number of accidents and fatalities, now numbering about 35,000 a year in the U.S. That's only likely to happen as features like Super Cruise become more common.