Sunday, June 15, 2008


Here is a little picture I drew to show how inefficient our road/car system is for transporting individual commuters during rush hour. The extravagant use of space really harkens back to a bygone era. They are even more spread out when they are moving!


We urban dwellers know we have a big problem every time we try to get to work. For what seems like hours we become zero efficiency machines with the many horses under our hoods jumping up and down going nowhere. Well maybe not ZERO efficiency..after all we are making some impact...we are obstructing others while spewing emissions from our tailpipes. We are taking up what could otherwise be productive space. We are depleting the world's supply of oil. We are empowering hostile governments...
It's easy to blame the cars......but let's consider, for a moment, another culprit. The roads.
One often overlooked point is that it’s not just that there are too many cars, but rather there are too few roads. While this may seem to be obvious and counter-productive, it raises a couple of important points. First of all, there is traffic because it is too difficult to add lanes in a timely manner. It is too expensive. There may be insufficient space. Now let’s think outside the box and be the three year old who just keeps asking, “why?”
“Well, Junior,” you say, “you need at least ten feet all along the way to add and extra lane..”
“Because it needs to be big enough for cars and even big trucks.”
O.K. now I’m even annoying myself. The point is that we forget that we have a road system designed for big heavy trucks, not the 1.2 person average occupancy of an average car. If you designed roads for commuters in gas sippers only, the lanes could be narrow, the asphalt thin, etc. More lanes, more throughput, faster construction, less money.
One of my main gripes with previous PRT designs is that they seem to forget this lesson. PRT needs to go everywhere a car can go without encountering the “we can’t afford more lanes” problem. It needs to be cheap with a capital C. It must not try to compete with other forms of mass transit between, say two points with only one or two stops in between. That is the realm of trains, or trolleys or buses. PRT should supplement these means by going to where ridership is insufficient to justify larger vehicles. A prime example of where PRT would seem to be less than a great choice is the only active (to my knowledge) program out there, the system to serve Heathrow Airport in London. If you already have people aggregated, and you are transporting them to a single destination, why use PRT?
P.S. Perhaps I shouldn’t use this as an example. In all fairness I haven’t really studied the specifics of that project. Perhaps there are enough terminals on one end and a massive enough parking lot on the other to justify personalized routing. I really don’t know..The point is that PRT needs an extensive network, not just a circular route. That means cheap track, as opposed to the huge cost of expanding truck capable roadways.


Accidents- 72 43
Anderson, Dr. J Edward- rebuttal of Anderson's arguments for supported vehicles- 32 paper on PRT control- 23, comments regarding "rules for engineering"- 38
Active Wheels- Michelin's active wheel -30
ATSC-Automated Transit Systems Classification - 61
Angled Wheels- 65
Braking- 43 72
Bumper- in track hydraulic- 43 72
Business model - trouble with- 35
Climbing Slopes - 31
CO2 in a gallon of gas- 40
Control - 23, 20, 104, 105, 106, 109, 98, 100, 101, 77,
Concrete- prestressed concrete track - 60
Control System and Software- 41
Crash Tests -  43
Dualmode- 50, 11064
Electrical Lines- cost of burying 21
Encoders- 20
Freight- track and bogie design - 54, delivery of -55
Future- the future of PRT- 41
High-Speed- conceptual system design - 56
Linear Induction Motors- bogey design - 26
Magnetic Braking- 43
Passenger Preferences - 41
Roller Coasters, Wheels of- 65
SVN - Instructions for collaboration - 59
Safety - looking ahead - 23, 12
Skateboard- a modular auto design concept- 50
SketchUp - design repository instructions 59
Skyhook - concept of- 52
Software - 41
Slopes - cog design for- 31
Stations - 47, 48, 49 12
Status Quo - comments on the continuation of dysfunctional transportation systems- 40
Street lighting - 14
Suburban sprawl -27, 97
Switching - redundant switching mechanism design - 42 traditional "in vehicle" switching designs- 36
Torque Motors - 51
Tortoise - SVN program for Open PRT- 59
Track - industrial and freight 54, switching, 36 design profile, concrete-60, high-speed-54, impact on station design-47, 48, 49, see-through for dual 4 wheel bogies- 42 , profile analysis- 39
suspended vs supported 33, 32
Traffic- PRT traffic management 41
ULTra- hidden design attributes63, 64
Wheelmotors- 44, 31


Backyard Monorail Just for fun-
Bubbles and Beams 2 - Many PRT concepts are illustrated in this great YouTube animation 
Control of Personal Transport Systems - Anderson
Flyway Beamcars - Don't leave this site without checking the index. It's huge.  
Headway Limitations - Dr. J E Anderson describes his approach to this and some control issues.
Linear Induction Motor (AC) -general description and guidelines for use, from Baldor
Linear Induction Motors (LIMS)- Force Engineering's Website, links to how they work, etc.
MAIT- (Modular Automated Individual Transit) Non-Profit, promoting multi-modal approach
MonicPRT - This animation shows a ULTra-like system but with some twists
OKI Study   Ohio, Kentucky, Indiana' study which included assessment of a Taxi 2000 PRT proposal.

PRT Activism - Koren  (reasons for PRT's slow adoption)
PRT Consulting - As the name suggests
Rack (or Cog) Railways - using toothed track for slopes- Wikipedia
Station Design - Muller. Concentrates on "open-guideway" types, so would apply to autos as well.

Transportation Research Board
Wheel Motor - Wikipedia entree

X Prize - Big money for innovators