Related to roundabouts I liked this quote from Rock's farewell ITE message = about the future:

"Development of alternative design standards for different roadway classes = or types may be neccessary."

Bill Baranowski

Date:    Tue, 18 Dec 2012 16:25:53 -0500

From:    Gene Russell Sr <geno@KSU.EDU>

Subject: Re: ITE President's Message:  More roundabouts coming & classification

I agree, and it leads me to once again climb one of my soapboxes. Virtually climb that is,  as I don't really climb as high as I used to anymore.

Along with alternate design standards (I think we should use guidelines instead of standards) we need better classification of roundabout types. This has been discussed a number of times on the listserv, i.e., coming up with consensus names for some nonstandard types, etc.

Also, and this may be more important and also one of my virtual soapboxes to climb on, along with a more complete roadway classification  of roundabout types we need some rather extensive roundabout safety audits of a large sample of existing roundabouts to come up with a list of do's and don't's, by classification type as much as possible.

Gene

Subject: Re: Autonomous cars need roundabouts, too.

Can an argument be made that roundabouts are the optimal at-grade intersection design for autonomous vehicle human transport?

Does anyone know of studies being conducted regarding the psychological and physiological affects that might be associated with the human experience of traveling within a roadway network with autonomous navigation of conflicting vehicles through closely spaced gaps? 

Paul

>>> "VanElswyk, Abram" <avanelswyk@PA.GOV> 2/22/2012 6:58 AM >>>

The ULTra PRT system, which is fully self-driving and self-steering, uses a circular intersection to route pods between the two car park stations and the mainline.

http://maps.google.com/maps?=Heathrow+Airport&hl=en&ll=51.479465,-0.486955&spn=0.002699,0.006925&sll=28.772778,-81.371389&sspn=0.025429,0.110807&hq=Heathrow+Airport&t=k&z=18

Actually, every PRT system ever built - going all the way back to ancient line-haul systems like Morgantown - is a series of loops and grade separations. I don't think I've ever seen a proposal for a cross intersection. Since fully autonomous Googlemobiles essentially amount to PRT on public streets, I don't see why roundabouts would be any less preferable in that context.

Abram VanElswyk | Civil Engineer Transportation Pennsylvania Department of Transportation Bureau of Project Delivery | Highway Delivery Division 400 North Street | Harrisburg PA 17210

Phone:  717.705.8535 | Fax:  717.705.2379 www.dot.state.pa.us<http://www.dot.state.pa.us/>

Date:    Wed, 22 Feb 2012 11:20:07 -0500

From:    TONY Redington <tonyrvt99@GMAIL.COM>

Subject: Re: Roundabouts obsolete in 20 years?

Hi:  Lots of good points.  One key as pointed out is capacity--the roundabout will move more objects of all types than a typical cross intersection regardless of the evolution of technology.  Second when studying metro transit in University of Maine at Orono in the 1970s the assumption was there would be little difference in transport modes within the foreseeable future--that assumption was correct, the modes did not change since.  Nor, one can argue will modes change appreciably in the foreseeable future--fuels and vehicle characteristics may change but cars, trains, buses and the "active" modes (walking, bicycling) will endure.  The mix of vehicles, vehicle miles for wheeled modes, development densities (affecting use of transit, etc.) may well change, at least in North America (yes, we will look more like those socialist Europeans in the future!).

Here in New England (six states) the growth of car travel is official over--3% gain per average state last decade with Rhode Island a negative

0.5%.  This changes a century of unmitigated growth!   Since the roundabout especially benefits all aspects of the walking mode (particularly safety and reduced delay--ditto service for the bicycle) the "active" modes should flourish; public transit and rail already grow at double digits while the car travel dwindles; and for much of this region driving age population is flat.

For Gary, then, part of the argument for roundabouts can involve the greater capacity of roundabouts benefiting all modes, the reduced area of pavements needed at intersections (no turn lanes), reduced energy consumption (regardless of source), etc.

Meanwhile, I am looking forward to my Maglev trip this fall in Shanghai and hope there are no jaywalkers or crazy bicyclists in the way.

     Tony

On Tue, Feb 21, 2012 at 1:04 PM, Batson, Scott < Scott.Batson@portlandoregon.govwrote:

Not getting into the validity of a magazine article where sensation sells, the assumption that a small and portable microprocessor is 

going to be able to match the human brain any time soon is ridiculous. I love the quote about it being an accident cars were invented before 

computers (ignoring that a horse and buggy is a 'car').

Built into the story are assumptions about transportation going in the opposite of the current direction, away from the more affordable mass 

transit and toward the less affordable, prt dream of my own vehicle, just for me.  Just what we need, more cars on the road.  Then there is 

the loss of personal control over personal vehicles issue - how likely are people to give that up? So, if all these people are driving these 

small personal vehicles, wouldn't they need to go pretty slow, say 20 mph?

Oh wait, that vehicle is called a bicycle.

How about legal questions? Do we sue Google when a crash happens?

Technology Will Save the World!

-Scott Batson

Hi Gary: It's hard to say what will be obsolete in 20 years.  After 50 years, I'm still waiting for my flying car. But, world oil production 

is now on the downslope and the US population is increasing at a fairly predictable rate: 403 million people in 2050 and 572 million in 

2100. I'm trying to imagine all of those people in single family homes and single occupant vehicles, but that looks mighty unlikely. I expect 

apartments and electrically operated rail transit systems will be the norm, built either by advance planning or eventual economic necessity. 

Looked at in that temporal frame of reference, roundabouts probably are a stopgap measure, but the pavements will wear out in 30 years 

anyway. Regarding her argument, roundabouts' main economic benefit is not safety but time savings. Delay is worth about $15 per hour. Add it 

up 24/7 X 20 years and the numbers are enormous, even when discounted for inflation. Of course, all of that will be moot if the world ends this Dec 21. :!

 -)  All the best, - Ed

Date:    Wed, 22 Feb 2012 12:56:53 -0500

From:    Edmund Waddell <edmundwaddell@HOTMAIL.COM>

Subject: Re: Roundabouts obsolete in 20 years?

Regardless of the vehicles' energy source, roundabouts with sufficient capa city conserve vehicle inertia and save energy compared to stop-n-go traffic  systems. Tony -  See what you can find out about the energy required to si mply elevate the maglev vehicle. In maglev, support from rolling wheels is  replaced by magnetic repulsion. Does the energy savings from reduced fricti on offset the additional energy required to elevate the vehicle?  The track  is also an issue. High speed rail can also operate on standard track. Magl ev track is much more complex and expensive. Speed is only a significant ad vantage in long trips. Where is the economic break point in separation dist ance between stations vs. high speed rail? If the stations are close togeth er, the economic advantage of increased speed would disappear.2020 Is maglev an interesting novelty or a practical transport solution? For wha t trips is it cost effective compared to alternatives?  - Ed