Saturday, March 19, 2016

PRT LITE

Mass ownership of cars surged after WW-II causing massive congestion and urban flight in the US. Eisenhower sealed the problematic deal in the 1950s in the deteriorating Interstate Highways that put down a continental network. It ripped apart cities. Transit use declined dramatically. Urban cores were almost abandoned. Some were.

In the 1960s the principles of PRT were understood, many seeing them as quite effective. Urban leaders baulked at the ugliness of widespread elevated guideways and stations. USDOT dabbled with R&D in the early 1970s, but put the option on ice for the 1980s and beyond. What was good for Detroit was judged good for the country. We become the Asphalt Nation that we are, now in a melt-down car world. 

The Morgantown PRT operated in hilly isolation. Transport engineers and urban planners ignored it.  They are still largely ignorant of it.

Three modest PRT shuttles opened in recent years outside the US. Despite fanfare and bravado from suppliers and fans, nothing has happened. Vectus and Ultra seem moribund. 2getthere - whose driverless vehicles are not locked into a guideway - has a brighter prospectus.

It’s the Elevated Spaghetti, Stupid!

PRT doesn’t make any sense without an extensive network. The more destinations served by it, the more attractive its non-stop service. Unfortunately the extent of the infrastructure becomes pervasively intrusive (and costly). 

Think no small plans!  The problem is that big PRT plans are scary. The inventor of Skytran recently said cities are ugly, so the ugliness of spaghetti-in-the-sky PRT isn’t a problem.  The proponent of TransitX is similarly oblivious to the issue. PRT promoters don’t really like to deal with it.

An urban mode needs to have extent
coverage to be effective.
Creating a network that puts tailored transit service portals into scores of urban nooks and crannies has appeal.  Eisenhower made it the post-war assumption that cars and other vehicles do it all. To be a viable urban citizen, you need a car.

In the multi-stations PRT world of the future, you will prefer to be within a quarter-mile from a PRT station.  Location, location, location!

But the guideways? Not down my street! Not in my neighborhood!

Robocars Rule!

Enter autonomous vehicles and the dozen labels already stuck on them -- automated, driverless, self-driving, i-cars, e-cars, etc. The onset of robocars is scary to many. Can they be safe? Will they solve or intensify congestion? Are they affordable?

The answers are:  yes, depends on planning, and yes.

Good links need good coordination with land management.
The even better news is that smart vehicles in smart districts can provide PRT-like service without guideways and stations. That massive fixed infrastructure is reduced to hundreds of devices, each smaller than a fist, no more intrusive that the thousands of security cameras now laced throughout our buildings. PRT devices will be embedded into curbs, sidewalk, utility poles, and buildings.

Vehicle-to-infrastructure communications will go both ways. Data from thousands of sources will come together to inform network operators. Each robocar will get guidance (control) enhanced by real-time routing informed by network traffic conditions. 

Multiple points - everywhere, almost - will have access to driverless, taxi-like services for trips rarely over five miles. 

It’s PRT without the spaghetti!

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