????無人駕駛汽車與我們的距離可能比任何人想象的都更近。今年，凱迪拉克（Cadillac）將推出兩款新車型的高科技版本，能讓我們能一窺未來電腦代替人來開車到底會(huì)是什么情景，盡管可能只是驚鴻一瞥。

????據(jù)通用汽車（General Motors）的工程師稱，一系列全新傳感器、報(bào)警裝置和自動(dòng)控制已能讓駕駛者察覺危險(xiǎn)情況、避免事故。通用汽車相信，通過將導(dǎo)航和決策算法與這類系統(tǒng)捆綁，無人駕駛汽車終將成為現(xiàn)實(shí)。該公司表示，第一款“半自動(dòng)”汽車將于2015年問世，更高級(jí)的版本則將于2020年面世。

????雖然新款高級(jí)安全系統(tǒng)并不能包治百病，但它對(duì)那些開車時(shí)犯困，或因?yàn)榇蚴謾C(jī)、喝咖啡、責(zé)罵孩子而注意力渙散的駕駛者來說無疑能達(dá)到以防萬一的備用效果。 “還存在不少問題必須解決，特別是汽車越來越多的更多功能實(shí)現(xiàn)自動(dòng)化之后，如何讓駕駛者保持注意力集中，”即將于下月退休的通用汽車研發(fā)部主管陶藹倫稱。“自動(dòng)汽車不是空想，它離我們比很多人想象的都要近。”

????今年1月，奧迪公司（Audi）在消費(fèi)電子展（the Consumer Electronics Show）上宣布，它正“積極研發(fā)”并擬于“2015年至2020年間”推出一套半自動(dòng)輔助駕駛系統(tǒng)。在車流擁塞、車速緩慢的路況中，比如在高速公路上，這套系統(tǒng)能讓駕駛者切換到半自動(dòng)模式，從而讓汽車以合理的車速在車道上保持行駛，同時(shí)避免與其他車輛相撞。這套系統(tǒng)可能會(huì)首先裝備在奧迪A8旗艦車型上。

????去年，內(nèi)華達(dá)州成為美國首個(gè)修改法律、允許無人駕駛車輛上路的州。眾所周知，谷歌公司（Google）已用一輛自動(dòng)駕駛汽車進(jìn)行過試驗(yàn)。另外德國馬牌輪胎公司（Continental）也已開展過類似的試驗(yàn)。

????今年3月，我和幾位記者受邀前往通用汽車位于密歇根州米爾福德的測(cè)試基地。此次邀請(qǐng)主要是向媒體證明自動(dòng)駕駛的可靠性，包括展示幾項(xiàng)技術(shù)和系統(tǒng)。當(dāng)時(shí)最令人興奮的是我們親自試駕了一輛特別配置的凱迪拉克SRX，以體驗(yàn)其半自動(dòng)“超級(jí)巡航”（Supercruise）的強(qiáng)大性能。

????當(dāng)時(shí)，副駕駛座上坐著一位通用汽車的工程師。加速到時(shí)速60英里時(shí)，我啟動(dòng)了“超級(jí)巡航”功能。我把從方向盤上拿開，但這輛SRX依然保持了適當(dāng)?shù)乃俣龋⑶医z毫沒有偏離車道。很快，另一輛試驗(yàn)用車從左側(cè)逼近，并切入到我們的前方。這時(shí)我的車自動(dòng)減速，與前車保持了安全距離。而當(dāng)前車變道后，我的車又重新自動(dòng)加速。

????隨后，另一輛車從右側(cè)超車到我們前方。結(jié)果，我們的車采用LIDAR，也就是一套運(yùn)用光波的傳感系統(tǒng)，成功地避開了這輛車，并且毫無異常或突發(fā)動(dòng)作。

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????Self-driving cars may be closer than anybody realizes. Cadillac is rolling out high-tech options for two new models this year which provide -- however brief -- a glimpse into a future where computers take over from drivers.

????An array of new sensors, warnings and automatic controls can already help drivers detect hazardous situations and avoid accidents, according to General Motors Co. (GM) engineers. Eventually, by bundling navigation and decision-making algorithms with such systems, GM believes a self-driving car is feasible. The automaker said the first version of a "semi-autonomous" car might be available by mid-decade and a more advanced version by the end of the decade.

????While new advanced safety systems aren't a panacea, they will no doubt provide a backup to drivers who doze off or whose attention wanders while using the phone, drinking coffee or scolding the children. "There still are issues that must be solved, specifically how to keep the driver's attention engaged as more of the car's functions become automatic," says Alan Taub, who is retiring next month as head of GM research and development. "The autonomous car is quite real and closer to reality than many people think."

????In January, Audi announced at the Consumer Electronics Show that it is "actively developing" and intends to offer "by mid- to late-decade" a system that will allow drivers in slow-moving heavy traffic, such as on the freeway, to switch to a semi-autonomous mode that will keep the car moving in its lane at a reasonable speed while preventing it from hitting another vehicle. The feature likely will appear first on Audi's A8 flagship sedan.

????Last year, Nevada became the first state in the U.S. to adapt its laws so that driverless cars may operate on its roads. Google (GOOG) has famously experimented with a self-driving car, as has the tiremaker, Continental.

????In March, I was among several journalists invited to GM's Milford, Michigan proving grounds for a briefing on autonomous driving, including demonstrations of several technologies and systems. By far the most dramatic was a "drive" behind the wheel of a specially outfitted Cadillac SRX to show the capability of its "Supercruise" semi-autonomous capability.

????With a GM engineer in the SRX front passenger seat, I accelerated to about 60 miles an hour and activated Supercruise. With my hands off the wheel, the car maintained the proper speed and didn't stray from its lane. Soon a driver in another GM test car approached from the left and cut in front of my car, into my lane. My car slowed down, keeping a safe distance behind it. Once it left, the car sped up again.

????Next the car cut into our lane from the right. Again, our car -- using LIDAR, a sensing system that employs light waves -- avoided the second car without any jarring or abrupt actions.????