File
One of Google's more than four dozen driverless cars currently roaming the roadways from California to Texas. Image source: Mark Doliner via Wikimedia Commons.

Driverless cars grabbed headlines in 2015 -- and mostly in a good way.

This was the year that Google, which now calls itself Alphabet (NASDAQ:GOOG) (NASDAQ:GOOGL), took the wraps off its self-driving-car project and began reporting detailed information on its progress in monthly progress reports. And in fact, if we're going to run down the top five driverless car headlines in 2015 -- let's start with that one.

1. "Google Self-Driving Car Project Monthly Report -- May 2015"
Alphabet's first report on its driverless-car project came out in May. In it, Alphabet described how the company's 32 self-driving test cars (a mix of Lexus RX 450h SUVs and self-designed prototypes) had racked up more than 1 million miles over six years of autonomous driving on both closed tracks and public streets.

At the time, this driverless fleet (with humans serving as copilots, ready to take over if needed) was putting in 10,000 autonomous miles per week. Over the course of six succeeding updates, Alphabet described the growth of its driverless-car fleet and its expanded testing from public streets in Mountain View, California, to Austin, Texas. At last report, Alphabet's now-53-car fleet was averaging 10,000 to 15,000 autonomous miles driven every week -- about as much as one average car drives in a year.

Total miles driven without a human hand on the wheel: 1.32 million miles.

2. "Google's Robot Cars Crash 'Surprisingly Often,' Because Humans Are Idiots"
This particular headline appeared on Wired in July, and its import is self-evident. Alphabet's driverless cars have been involved in a total of 17 "minor" accidents over the past six years, including five racked up in just the past six months.

In part, that increasing crash frequency is a function of Alphabet's putting more cars on the road. But it's more a function of how many humans are on the road already. Alphabet driverless-car boss Chris Urmson noted in a blog post that every single accident his cars have experienced over the past six years was the result of human error. -- i.e., not the cars' fault.

Says Urmson, "Our self-driving cars are being hit surprisingly often by other drivers who are distracted and not paying attention to the road ... and not once has the self-driving car been the cause of the collision."

3. "1 in 3 Americans Won't Consider Buying a Self-Driving Car"
Even if that's true, calling other drivers "idiots" may not be the best way to win them over as customers. According to a March report from Harris Interactive, 50% of potential car buyers surveyed in a recent poll say they -- personally -- do not think driverless car technology is ready for prime time right now.

Potential customers point to the cost of driverless cars, their complexity, and a fear of computer "glitches" as factors they worry about. The upshot is that 33% of respondents surveyed in that poll aver they "will never consider buying or leasing a self-driving vehicle."

If that's the way people feel about driverless cars, Alphabet's autonomous vehicles may be dodging "idiot" drivers for many years to come, before the highways go truly driverless.

4. "California's Proposed New Rules Could Slam the Brakes on Driverless Cars"
Consumer reluctance to "early adopt" driverless cars is only part of the problem. Government regulation could build another speed bump -- and in a most surprising place.

Home to Google/Alphabet/whatever we're calling it this week, California has until recently been pretty friendly to driverless cars. In September, the California Department of Motor Vehicles announced that it was permitting Honda to begin testing driverless cars in-state. Three months later, Ford (NYSE:F) joined the list. As of today, a total of 11 separate companies have received permission from California to test autonomous vehicles on public roads.

Yet, according to the preceding headline from Jalopnik, even once these companies have completed their testing and developed a driverless car for sale, new proposed regulations from the California DMV threaten to make that transition from testing to sales more difficult. The rules require, for example, that driverless cars obtain "third-party testing and certification," that the cars have a backup human driver with "special certification" present, and that the cars be equipped with steering wheels and control pedals for the driver to use.

These rules threaten to limit driverless-car companies' ability to innovate to develop a product that will overcome consumer reluctance to buy into the new concept. They also threaten to slow down sales by requiring anyone who wants to buy a driverless car to obtain "special certification." For that matter, the rules may even ban sales outright and limit consumers to leasing the vehicles.

5. "Google Pairs With Ford to Build Self-Driving Cars"
Yet progress marches forward. Just last week, Yahoo! Autos reported that no sooner had Ford received permission to begin road-testing driverless cars in California than the company may be preparing to tie up with Google on a driverless car project.

It's not clear at this point whether Ford would merely build cars for Google to test, build cars for Google to sell, or just license Google technology for incorporation into a driverless-car product of Ford's own. This may not remain a mystery for long, though. According to Yahoo! Autos, Ford will make an official announcement about the partnership at the upcoming International Consumer Electronics Show in Las Vegas, where Ford CEO Mark Fields will hold a press conference on Jan. 5.

What that tells us could determine whether 2016 is as big a year for driverless cars as 2015 already has been. 

Rich Smith does not own shares of, nor is he short, any company named above. You can find him on Motley Fool CAPS, publicly pontificating under the handle TMFDitty, where he's currently ranked No. 308 out of more than 75,000 rated members.

The Motley Fool owns shares of and recommends Alphabet (A and C shares). The Motley Fool recommends Ford. Suzanne Frey, an executive at Alphabet, is a member of The Motley Fool's board of directors. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.