I’ve been intrigued by [Personal Rapid Transit->] since 2002. I’ve gone so far as to do some software modeling and simulation of a PRT system for San Marcos (with a station right by my house, natch), and those of you unfortunate enough to live near me have probably been regaled by my excited blathering on the subject from time to time. (“Good goshamighty, why won’t he be quiet? Shut up! SHUT UP! He won’t stop. Ok, I’m going to my happy place now. Thinking about unicorns and cheesecake. Mmmmmm…cheesecake.”)

But as of today, I’m no longer a fan.

The reason? Not any particular deficiency on PRT’s part. It’s still quicker, more efficient, and generally much more desirable than private cars or other public transit options.

But today, I discovered Robocars.

What are Robocars? Cars that can drive themselves. DARPA’s Grand Challenge in 2004 and 2005 showed that autonomous vehicles were a technological possibility. The 2007 Urban Challenge demonstrated that they could function on normal roadways, dealing with traffic laws, other vehicles, and pedestrians along the way.

Once you have vehicles that can drive themselves, a fleet of them (run by, say, a taxi company) offers nearly all of PRT’s advantages without its drawbacks. Consider these improvements on the PRT concept:

• Robocars operate on existing roadways. There’s no need for a dedicated infrastructure like PRT’s.
• If a Robocar breaks down, it can easily be moved out of the way like a car. It wouldn’t block an entire monorail line like a failed PRT tram would.
• Implementation of Robocars would not need a huge initial investment from a central government, but can be introduced one at a time, just like automobiles. It can therefore happen as gradually or rapidly as the market dictates.
• By communicating with traffic lights and ensuring optimum travel speeds, Robocars could be nearly as efficient as a PRT system.
• One can have personal ownership of a Robocar if one wishes.
• Robocars remain useful as you move out of urban areas.

Robocars, like PRT, offer even more advantages over traditional cars and transit systems: fuel efficiency, convenience, safety, flexibility, and the ability to both enjoy a private space and to do other things while in transit.

See Brad Templeton’s Introduction to the idea for an overview of what it’s all about, or for a glimpse into the possibilities, read his fictional account of what a week with Robocars might look like.