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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