????消息靈通人士關于自動駕駛汽車的深談已經與可行性無關了，現在大家關注的焦點是“什么時候上市？”，“哪家汽車廠商會首先推出這種車？”以及“如果發生事故，責任到底在哪方？”

????日產汽車（Nissan）已經表示將于2020年銷售無人駕駛汽車。IHS咨詢公司預計，到2025年，市場將推出好幾款此類車型。這兩個消息都有猜測的性質——但它們表明，這項技術的發展是何等神速。

????十年前還顯得那么不可思議的事情現在已經變得十分可行，可以理解，而且無比真實了。谷歌（Google）那輛自動駕駛豐田普銳斯（Toyota Prius）已經在加州的公路上安全行駛了上萬英里，沒有出過任何事故。大多數汽車廠商正在賽道上測試自動駕駛汽車，同時——最近，正如我本周初在拉斯維加斯體驗的——也在真實路況中開展這種測試。

????奧迪A7搭載了一套“堵車輔助系統”，它能在嚴重擁堵的車流中以每小時不超過40英里的時速自動駕駛（測試時奧迪項目組組長比約恩?吉斯勒博士就坐在駕駛席上）。這輛車上裝了各種攝像頭、傳感器和一套特殊設備，能監測駕駛者眼睛的情況，以確保司機開車時不要睡著。如果司機真的睡著了，這輛車就會穩穩地減速、停止行駛，請求援助。

????大家不妨把無人駕駛汽車看成是機器人。對奧迪公司（Audi）和其他汽車廠商來說，關鍵問題是駕駛中到底有多少該由機器人來完成，多少該由駕駛者來完成。這其實最終還是取決于駕駛者自己。奧迪和其他品牌的高管都表示，駕駛者無論如何都必須保持介入和警覺，發生開錯道或失控這類意外時要能隨時重新接管車輛。

????奧迪的高管從來不用“無人駕駛”這個字眼，他們說的是“引導式”駕駛。其他品牌的高管說的則是“自動”或“輔助”駕駛。只有谷歌堅稱自己要研發的就是無人駕駛汽車，也就是能幫助老年人和盲人，以及那些寧可在車上讀書的人的自動駕駛汽車。

????Informed conversations about self-driving cars no longer are about feasibility. New key talking points are "When?" and "Which automakers first?" and "Who will be responsible when an accident happens?"

????Nissan has said it will sell a driverless car by 2020. IHS forecast several models available by 2025. Both of these are guesses -- but they indicate how fast the technology is progressing.

????What seemed unimaginable a decade ago becomes more practical, comprehensible, and real by the day. Google's (GOOG) self-driving Toyota Prius (TM) has logged hundreds of thousands of miles without incident on California roads. Most automakers are testing self-driving cars on tracks and -- lately, as I experienced earlier this week in Las Vegas -- in traffic.

????The Audi A7 equipped with "traffic jam assist" was programmed to drive itself slowly in heavy traffic at no more than 40 miles per hour. (Dr. Bjorn Giesler, head of Audi's project team, was behind the wheel.) The car was loaded with cameras, sensors, and a special device that monitors a driver's eyes to ensure he or she doesn't fall asleep at the wheel. In that event, the car will safely slow down, stop, and call for help.

????Think of a driverless car as a robot. For Audi and other automakers, a key question is how much of the driving should be done by the robot, how much by the driver. The driver decides. Executives at Audi and other automakers say the driver, in any case, must remain engaged and attentive, ready to take over in the event of the unexpected: a car travelling the wrong way or out of control, for example.

????Audi executives won't use the word "driverless;" instead they speak about "piloted" driving. Other auto executives talk about "autonomous" or "assisted" driving. Only Google is adamant that it wants a driverless car, one that can help the elderly and the blind, as well as anyone who would rather be reading a book.