Order of Kilopi
Hi, I take note that the new LED traffic lights installed in the great white north have considerable problems when there is snow. They do not generate enough heat, like the older bulbs, so as to melt the snow and ice away.
Wouldn't you think they would have tested this in R and D before they shoved them out into the field?
It cost someone their life... in the news. Sheesh. I'm glad they don't work on my brakes.
Best regards,
Dan
Order of Kilopi
Yes; if they were aware of how the heat from the bulbs melts the snow.Originally Posted by danscope
The problem is, how well know is it that this actually happens in the first place. We've had lights with no snow on them, but we have no idea if anyone really took notice that it was the heat of the bulb that did that.
Established Member
Link explaining the fatality? Did the obscured light actually cause the death, or was it someone simply not driving to the conditions..? Hereabouts if a traffic light can't be seen, I, and most other vehicles, tend to slow way down.
I get quite annoyed when I hear news reports that say things like "the accident was caused by the driver in front, braking suddenly..." (I heard that said on radio only a few weeks back..grrrr) No, it was caused by the driver behind not leaving enough space between vehicles. It's called 'driving to the conditions'.
</rant>
Order of Kilopi
Hi, Clearly the driver just blew through the light without any question or concern. But the red light was completely covered due to the fact.
The link was local abc 6 news in Providence, RI. I'll see if my skills are sufficient to put up a link.
Still, I should have thought that these developerswould have tested in the real world before deploying.
They save energy but at a cost of lives. A bad trade off to me.
Dan
Established Member
Unfortunately much of the R&D occurs in warmer climates.
My 2007 Jeep was developed in the California. The first winter we had it the check engine light starts flashing. It turns out the computer system wasn't programmed to understand that in a Canadian winter there can be a marked difference in temperature between the engine compartment and the engine. Because of this the computer thought the engine was overheating and shut the engine down, on the highway, 20 min out of the city. Once we stopped for 5 min the heat from the engine warmed the engine compartment, the computer decided it was ok to start the engine, and we turned around for home. The dealership was thankfully open and we stopped in to get it checked out. The mechanics were stumped about the problem until it read the computer readouts and figured out that it was programming error. Apparently they were able to disable the check in the system and we were on our way.
When I was driving truck, Freightliner came out with a 10 gear transmission with the top 2 automatic. I was driving west just past Regina, Saskatchewan and hit black ice. The transmission started flipping between gears because it didn't understand how to handle ice. Thankfully after 5 seconds it gave up and went into "neutral mode" when I could then tap the clutch and put into a full manual mode. Almost jackknifed because of it. Again the R&D for the transmission occurred in the Texas and Nevada where ice on the Highway is a rarity.
Order of Kilopi
That's only true, I'm sure, if you know (or have reason to believe) there's a traffic light there in the first place.
Absolutely. I had a co-worker once who rear-ended somebody. She said the cop didn't give her a ticket because he couldn't be certain she was following too closely. I didn't say anything, but I thought, "I wasn't even there and I know you were following too closely."
Administrator
I work in R&D (not on traffic lights) and I can tell you that the fault always lies with either Manufacturing or Marketing, and sometimes with QA. Accounting doesn't look too innocent either.
OK, I'm joking. But often, the problem with such developments isn't so neatly put on one person or one department. Maybe R&D had plans to test the traffic light in different climates, but Marketing said we don't have time for that, our competitor is about to get to market with a similar product. Maybe there were some problems in the testing protocol that QA came up with. Maybe they (R&D, Marketing) told the customer that this was a problem and you had to install a heater and the customer didn't.
Order of Kilopi
Used to work with the Peoplesoft database system. They claimed it was a multilingual system. It's improved since earlier versions, but it still isn't. It's a localized system. You can use it in any _one_ language you want. New Brunswick is a bilingual province. Government entities (including the community college network) have to produce output in both official languages, sometimes simultaneously.
When our lords and masters went system shopping, they knew to ask if the proposed systems were bilingual, but it never occurred to them that system makers develop their products in regions where the term "bilingual" isn't really understood. Not the way New Brunswickers do.
Order of Kilopi
Well, you make the excellent point that good engineering gets steamrolled by marketing types. What's reason got to do withit? Pity.
Best regards,
Dan
Order of Kilopi
Hi Moose,
" Oh, you want your system in two languages?"
"No, we want it in two languages."
With appologies to Eric idle .
Order of Kilopi
Heh. Eric Idle was right.
"Either of two languages' and "both languages" is a fine distinction, but it's an important one in my province.
Actually, they could have solved the whole thing by simply not treating English as a special case in the database design. Had English been treated the same as every other language, 99% of the issue would have been solved without any sort of fuss whatsoever. The localization was an afterthought.
Honored Member
"Take off your engineering hat and put on your management hat."
I remember that from somewhere.
Order of Kilopi
Order of Kilopi
How do we know that there isnt a warning on the lamp that it would have trouble in cold weather? It may be that the local roads department either ignored or didnt understand the problem.
Order of Kilopi
Hi, the purchase of highway safety equipment such as traffic safety lights
is in no way a casual purchase, and when you sell someone all weather equipment in Wisconsin, it is obvious to the most casual observer that the
purchase is to give excellent service throughout Wisconcin's winter, which is a most substantial test of cold weather durability and suitability in that environment. Traffic signals are no place for a cheap third rate con artist.
This wouldn't fly with the airlines or the Navy. I think that we will be hearing more about this as time goes by.
Best regards,
Dan
Order of Kilopi
I googled "led traffic lights don't work in snow" and got pages of references.
Looks like a few people are thinking about it. Hmmm....
Dan
Established Member
Just don't give them those silly hoods that wrap all the way around to the bottom and give the snow a ledge to pile up on. There was never really a point to that anyway.
Established Member
Well, I don't live in a zone that ever sees snow, but our traffic lights (poles, light boxes, hoods, etc) are generally black. I find it hard to envision how they could ever be covered in snow in such a way as to make them hard to see.. And even so, if you can't see much, you SLOW DOWN. If there is any risk of an intersection hiding in the snow, let alone a traffic light, afaics there just isn't any excuse - see final sentence below...
This also raises the question in my head, aren't the lights hooded in such a way as to prevent the deposition of snow on the light? OK, I just looked around and found this...
http://news.yahoo.com/s/ap/20091216/...red_stoplights
Why on earth do the shrouds curve inwards at the base of each light?? On that issue I would ask questions of the designers..
Yup. The only rear-ender that is the fault of the person in front, involves him/her reversing (or rolling backwards down an incline)..
And as they say, a non-working traffic light is a STOP SIGN.
Order of Kilopi
Does the same thing apply with buiding design? Cause the power connections here in Houston are well designed for winter. Too bad we dont get winter, but we do get tropical storms that end up blowing out a large section of the power grid cause all the transformers are in the basements without flood controls...
I guess that I should way were well designed. Now they are modified for tropical storms (allison) and hurricanes (ike)
Order of Kilopi
Two words. Blizzard conditions. Rafts of flakes really coming down, getting blown sideways, covers everything, including traffic lights, even bulbed lights, apparently, which I guess eventually melt the snow, but not always immediately.
Right. If you can't tell if it's red or green, it's a four-way stop.
Everyone is entitled to his own opinion, but not his own facts.
Order of Kilopi
"No problema!"January 8, 2010
...In April 2009, the problem of snow covered L.E.D.s had deadly consequences. A woman was killed after a driver crossed through an intersection in Oswego, Illinois, where snow had made the traffic lights white. The driver says he couldn't see the signals. Other accidents blamed on covered signals are also being reported in places around the midwest.
Evanston, Illinois, traffic engineer Tom Twigg...says he's still in favor of the L.E.D.s, saying that when these high tech signals are whited out, there is a quick, low-tech fix . "Its nothing sophisticated, its basically brushing it off is all it is. It's not a permanent bond on there, you can take a glove or just wipe it right off"...
foxnews.com
Order of Kilopi
What fox fails to grasp is that the light is 18 feet above ground, and cities and towns don't have the manpower to go around cleaning and wiping
the traffic lights every 15 minutes.
It sounds to me like they need a system for winter( old style bulbs) and then put in the led's for the warmer weather. Duh .
You don't replace a good system with a poor one. To quote jeff Goldblum,
" Just because you could... doesn't mean you should . "
Order of Kilopi
I read an article on this a few weeks ago, and they said that most people do treat frozen over lights as stop signs and take appropriate action. If it weren't for that, the accident statistics would probably be horrifying. As it is, there are still enough accidents to look for solutions.
I say there is an invisible elf in my backyard. How do you prove that I am wrong?
The Leif Ericson Cruiser
Order of Kilopi
That's still quite a bit of work. The LEDs save money two ways: They use less power, but they also save in maintenance costs because they last much, much longer than conventional bulbs.
I'd suggest leaving the LEDs, but perhaps adding a temperature controlled heater coil (and only a heater coil that was designed to last many years). But there might be better options.
I say there is an invisible elf in my backyard. How do you prove that I am wrong?
The Leif Ericson Cruiser
Order of Kilopi
FOX? Maybe you should read it again.
Order of Kilopi
Unfortunately much of the R&D occurs in warmer climates.
My 2007 Jeep was developed in the California. The first winter we had it the check engine light starts flashing. It turns out the computer system wasn't programmed to understand that in a Canadian winter there can be a marked difference in temperature between the engine compartment and the engine.
In the book "Computer Related Risks", there is discussion of the early F-16 software. When it was being tested in a simulator, the plane rolled inverted when it flew south of the equator. Outside of the simulator, the first deployment of the F-22 to Japan had to return to Hawaii when the software malfunctioned when the planes crossed the International Date Line.
There is often a problem when people developing a system don't take into account real world conditions that are different from the development environment. For example, when I worked at MCI about 15 years ago, a development team got into trouble. They were developing an early client-server system. Everything worked fine when they tested it but when they deployed it, the system was glacially slow (45 minute average response time). They developed the system on a 16 megabit Token Ring network but when they deployed it, most of the users had 9.6 kbit data lines. Oops!
Order of Kilopi
Strange thing about this subject is I have a
distinct memory of a childrens science
television program from 50 years ago telling
us that traffic lights used gas discharge
tubes for the different colours.
Perhaps they were useless with snow...
Order of Kilopi
Well I don't know, but here we have roofs on the traffic lights. That ought to help unless it's snowing horizontally.
Order of Kilopi
Those two are just very bad software development. No excuse for that.
Administrator
We also have roofs on our traffic lights (actually, more like a little tube with the light at the back. But, on the flip side, I have seen it snow horizontally around here.Well I don't know, but here we have roofs on the traffic lights. That ought to help unless it's snowing horizontally.
Order of Kilopi
I wonder if they will come up with a retro-fit de-icer and save the led system
which, in itself, in season has merit.
Best regards,
Dan
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