Comments on: Use Your Illusion II: Virtual Speed Humps Coming to Philly

By: what the?

what the? — Sat, 21 Jun 2008 14:10:45 +0000

Um, that looks like something that could damage a car. Hope no one swerves and causes a crash.

By: djsbon

djsbon — Sat, 21 Jun 2008 02:03:03 +0000

i think it's a great idea and i can't wait to see them in philly

By: Clarence Eckerson Jr.

Clarence Eckerson Jr. — Fri, 20 Jun 2008 06:33:17 +0000

I can't honestly say whether or not I dig this. I open my mouth and nothing comes out. Seriously. Equal parts clever and a head scratcher - even my fingers are having a hard time typing this.....
Okay, I give up. Maybe tomorrow I will have an opinion.

By: galvo

galvo — Fri, 20 Jun 2008 03:24:21 +0000

the speed limit needs to be lowered to 20 mph in these congested urban areas.

i remember the gas crisis of the 70's. The federal govt mandated that all highways had to reduce the speed limit to 55 mph to conserve fuel. Latter when the fuel crisis was over they tried to retain the speed limit at 55 mph to save lives.

By: Brooklyn Boy

Brooklyn Boy — Thu, 19 Jun 2008 23:54:45 +0000

I wonder if it would be admissable in court (for whatever reason), and then use that as an excuse for a red light ticket claiming to have considered it an optical illusion etc. LOL.

By: Eric McClure

Eric McClure — Thu, 19 Jun 2008 23:26:13 +0000

I don't know, I actually think it might work. I have a feeling people have an auto response to seeing something in the road, which will kick in even if they've been on the route over and over. i guess only time and data will tell.

(Which is not to say that municipalities shouldn't be doing all the things suggested above -- they should -- just that this might be a fairly cheap and effective way to achieve some speed reductions.)

By: escapehelicopter

escapehelicopter — Thu, 19 Jun 2008 22:34:32 +0000

It seems like a terrible idea to use optical illusions of any kind where driving is concerned. What's wrong with real speed bumps, roundabouts, and other physical barriers?

Creating an environment where something isn't as it seems and drivers don't experience the actual bump they expect could easily lead to drivers ignoring real speed bumps and having accidents as a result.

Let's 'keep it real'.

By: mr. brownstone

mr. brownstone — Thu, 19 Jun 2008 21:41:55 +0000

Boots - thoughtful comment - but one change: standard parking lanes in NYC are 8' or, on streets with little to no trucks parking, 7'. On bus routes it's sometimes more.

By: anon

anon — Thu, 19 Jun 2008 20:56:57 +0000

i'd support this if it was done by intrepid volunteers, a la roadsworth. but an official agency has the resources to do something more effective.

By: Boots

Boots — Thu, 19 Jun 2008 20:51:26 +0000

Narrow the street, put parking along both sides. Narrow streets equals slower speeds as people don't want to hit parked cars or people (one would hope).

The equation for "How narrow?" is easy. A standard car is 8 feet wide, (excepting smart cars and hummers, but average) so then each lane should be dealt with accordingly.

A standard parking lane then is 8-9 feet, and a driving lane of moderate speed is 10 feet. Increasing the driving lane size, say to 12 or even 14 feet makes for a very fast street. To make a SLOW street narrow the lane to 9 or even 8 feet.

So...

Slowish street: (2)Parking lanes 9ft each + (2) driving lanes 9 ft each = 36ft.

Slowish street: (1)Parking lane 9ft each + (1) driving lane 9 ft each = 18ft.

VERY SLOW street: (2)Parking lanes 8ft each + (2) driving lanes 8 ft each = 32ft.

EVEN SLOWER STREET: (2)Parking lanes 8 ft each + (2) driving lanes with pullouts at 14 feet = 30 ft.

You get the point and the math to make other streets works the same. Wide streets = fast streets, narrow streets = slow streets. The corrolary is that slow streets are SAFE streets for pedestrians.

By: Fritz

Fritz — Thu, 19 Jun 2008 20:39:27 +0000

Well, we're all agreeing on this. Clearly it's a questionable if not bad idea and there are other things that work... like bollards making roads a tight fit for cars will slow down the speed or alternate the sides on which you have them to make it a little more windy, etc.

By: paul

paul — Thu, 19 Jun 2008 20:27:35 +0000

Nice GnR reference. who knew that streetsblog brass are metalheads?

Seriously though, i see these having much diminished effect over time, as motorists get hip to the ruse. properly built speed humps or speed cushions (which can be spaced to allow emergency vehicles to pass) work fine. add neckdowns speed cams to enforce a lower speed limit (20 mph anyone?) and you have a much more effective calming strategy. its more expensive, but worth it because crashes are even costlier.

By: dchadwick

dchadwick — Thu, 19 Jun 2008 20:02:27 +0000

I agree with Matt above. I'd even say that if they all look the same, driving over one ANYWHERE will pretty much give the game away and drivers will ignore all of them. Maybe if they mix in some real ones that look identical to the fake ones, drivers won't know which they're approaching? What's really needed are some kind of retractable speed bumps that can be de-activated by special vehicle-mounted transponders (I'm thinking of the ones they're already using to change lights for buses and emergency vehicles).

By: Matt Kime

Matt Kime — Thu, 19 Jun 2008 19:49:03 +0000

I think they'll work once or twice then people will catch on to them - particularly people following a frequently used route.

By: Mark Walker

Mark Walker — Thu, 19 Jun 2008 19:37:15 +0000

As long as I don't get mistaken for a virtual pedestrian.