Idiot-proofing low clearances with water curtain stop signs

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Many years ago, while learning to code with my dad, I showed him something I’d written. He toyed with for a few minutes, and then, when prompted for text input, fed in some integers (and watched the little program roll over and die).
“You haven’t made it fool proof,” he said.
So, away I went, to spend considerably more time adding error-checking to every stage of the operation. I returned to him, hours later, to show him my improved version. He noodled about, and then turned to me. He’d made the little thing roll over and die, again.
“You’ve made it fool proof, but have you made it damn-fool-proof?”

Words to live by, those.


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• Amazing water curtain Stop sign (senbreaknews via dfaris)



That principle has already been demonstrated at the 11foot8 Bridge:


Hmm…don’t drive in front of tall trucks with the top down…


Any word on how it’s works in full daylight, like at the 11’-8"?

I wonder if part of the issue there is that “overheight must turn” feels more like a general warning than a directed notice that someone is overheight.

Maybe it would be better if it were more conversational. “You! Yes, you! In the truck! You’re too tall! Turn or else!”


Or, “You, in the truck! Wanna be on YouTube?”


If you rely on the idiot to be paying attention, you’ve already lost the battle.

A repeated issue I encounter involves getting stuck behind a big-rig that is moving slower than the flow of traffic. It doesn’t matter if it is during a clear, sunny day or if it is at night and the truck is covered in lights. As soon as I signal and change lanes to pass the truck, the idiot who had been behind me will floor their accelerator and immediately slam on their brakes to avoid rear-ending the truck they apparently didn’t realize was there.


A software tester walks into a bar. Orders a beer. Orders 0 beers. Orders 999999999 beers. Orders a lizard. Orders -1 beers. Orders a sfdeljknesv.


(Naeser’s Law)

Something about the way you told that story reminds me of the programmer who accidentally re-created Tron’s rogue programs.


So the trucker drives around a blind curve with vertical embankments on either side and no shoulder, gets all the way to the tunnel entrance, and THEN Sydney get really serious about stopping him? And then I guess he’s supposed to reverse back around the curve into oncoming traffic until he finds an escape route. I can’t see anything wrong with this plan.

The 11foot8 bridge is here in town. It typically catches inexperienced drivers who aren’t used to thinking about clearance. Sydney’s technique would work like a champ here. You can stop them while they’re still at the traffic light, giving them the opportunity to turn left or right at the intersection. But that’s not going to happen. Instead we installed a huge steel i-beam that operates like a can opener, sheering the top off the trucks. I have a feeling that someday I’ll be driving a rental truck through town and it will get me.


We have ‘speed check’ signs that light a display with your speed on it if you’re over the limit and the words ‘Check your speed’ (don’t know if you have them too, but we have a lot).

Point is, while it’s taking its data from a sensor concealed (or at least not made obvious) from before you see the sign, and as such actually is your speed, I’ve had a least one conversion where the driver thought it was a general warning, and the back of the sign was taking the speed of the car ahead. (No visible sensor, so must be behind the sign).

Anecdotes are only worth what they weigh, but this person wasn’t a dumb cookie, and even they thought that.

So yes, more ‘Yes, we mean you!’ in the signs. :slight_smile:

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I knew I’d seen that in fortune's default cookieset. :slight_smile:


It’s clever, but we already have an invention that does this, called the sign. But this new one wastes enormous amounts of water. Have they ever had a drought in Australia?


Either the speed-sensor signs in my city are all tuned too high, or I’ve never had access to a car with an accurate speedometer - I’ve never driven through one that didn’t read about 10 km/hr over what my speedometer said.

The ones they have on the highway have matched what my speedometer said, so if it’s a speedometer issue, then the cars I’ve used have speedometers that are only inaccurate at the low end…

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Does being an idiot somehow improve one’s survival or reproductive odds?

Because they do seem to evolve, don’t they?

(edit: I didn’t mean to quote @moosemalloy’s joke, I only meant to steal it)