News: Retractable posts should reduce crashes at corner of Cleveland

http://www.pointbuzz.com/news.htm?id=994

Ah. This might help redirect certain clueless motorists (most of whom have out-of-state plates...I won't say where, but you can probably guess...) who have apparently never seen either a double left-turn lane or a lane control marker.

(I remember watching a van from You Know Where insist on sitting in the left-turn lane clearly marked with the red X, then get hung up making his turn directly into oncoming traffic. It wasn't because he was trying to get ahead or anything, as he was the first vehicle to arrive at the intersection after the light turned red...it was just that he was clueless about the Big Red X, and I think he had probably never seen a double left-hand turn lane before...)

--Dave Althoff, Jr.

And if those drivers wish to challenge it...

http://www.break.com/index/large_truck_vs_pole.html

~Rob Willi

Are these similar to the safety poles in use in places like the White House? Obviously these are meant to spring up in thousandths of a second, but is it the same basic principle?

Maybe I'm picturing it differently, but what happens if your car is "in the line of fire" when they come up?

I'm assuming these are slower and less forceful than the safety barriers. But I am curious as well. If this comes up through the floorboards of someones car, I think they are going to be a little more than upset.

I would imagine there's some sort of threshold regarding the force that would reverse the motors if they were stopped by a few thousand pounds of resistance. Of course, this is purely speculative.

Now, a motorcycle, on the other hand...

Or if I am crossing the street and standing on it!!! I hope its less than a few thousand.

Most retractable delineator posts used in traffic organization are flexible and will not extend out of their shealth if an object is over them. Also, if a post takes a hit, it is like hitting a rubber cone... usually the vehicle and post are just fine.

JuggaLotus said:
Are these similar to the safety poles in use in places like the White House? Obviously these are meant to spring up in thousandths of a second, but is it the same basic principle?

Those seen in the video are definately physical restriction barriers, not visual barriers like the ones Sandusky is getting. Though, I've never seen the barriers at the White House, I'd imagine they're pretty similar to those seen in the video, but with a vastly quickened unsheathing time.

Well, the point of those is if a car jumps the curb to try and crash into a building, these will spring up when the car hits a pressure plate and block it. Extreme Makeover: Home put them in front of a house that had had a car (maybe 2) crash into it. The car blew the stop sign and went right over the curb into their living room.

Yours makes a bit more sense. Basically the same 2 inch ones that are already in use in some places but then make them retractable.

2 inches? Am I picturing the wrong thing here?

Also...

Vice Mayor Dannie Edmon was concerned the posts would come up when traffic was about to enter the lane. However, Engineering Director Kathy McKillips said the posts would retract if they were coming up while a car was driving over.

I'm sure it will retract, after poking the bottom of your car and causing who knows what kind of damage. I guess I can just picture one coming up and catching a hose or something underneath and ripping it off as I drive over.

Don't get me wrong, I think this is a great idea for helping guide traffic flow, but I just see some logistical problems.

Compare these poles to the ones that Cedar Point puts down the Perimeter Road behind the parking office in order to gain an extra entrance lane in the morning, and in the evening to separate traffic coming from the main lot from the traffic coming up from Perimeter Road as it approaches the Causeway. It's the same idea, except that the ones to be installed on Cleveland Rd. are retractable instead of having to be stuffed into the holes by highway workers.

In fact, what they are looking at is probably a lot like this.

Note the specs on obstruction detection, and on what happens if you crash into one.

Also, if I were setting up the equipment on that intersection, I would use at least three traffic signal cycles to activate all the equipment when reversing Butler St.--

1) Indicate that the far left-hand turn lane is closed and disable the one traffic signal

(some time passes)

2) Indicate that the center lane of Butler is closed to ALL traffic

(some time passes)

3) Extend the barriers on Cleveland Rd.

(some time passes)

4) Indicate that the center lane of Butler St. is open to opposing traffic

By activating the lane closed indicators at least one signal cycle before extending the barriers, there should be no vehicles in the turn lane when the barrier comes up anyway. Besides, the change that involves extending the barrier is most likely to happen in the middle of the night when there is little or no traffic anyway.

--Dave Althoff, Jr. *** Edited 8/16/2006 6:12:38 PM UTC by RideMan***

Awesome link! Thanks, RideMan.

I recall being in the far left turn lane when it went from the green arrow to the red X. That certainly freaked me out trying to figure out what I was supposed to do at that point because it's difficult to switch lanes to the right left turn lane at that point.

A staggered/warning implementation would be much better.

Butler Street is the weirdest street I have been on. That is the only street I have ever seen that switches directions in the middle of the day. I am very glad that we don't have lane control things in the part of Michigan I live in. I don't even know if any place in Michigan has those.

You'll usually see those kind of lane controls on tunnels and bridges.

--Dave Althoff, Jr.

MAF - I know they had them by the Silverdome. Possibly by the Palace as well. Before games, 4 out of 5 lanes will be inbound, afterwards, 4 out of 5 will be outbound. It really does help.