How to connect traffic light circuit with road spikes?

Baaad idea, but easily done using the same control system for the lights. It’s never been done because well, it’s a really bad idea.

It really shouldn’t be that difficult.

Either the traffic lights have a mechanical timer (very old school) or they have an integrated circuit that acts as the controller. In either case something in the controller box sends an impulse down the circuit to cause the color to change.

What you need to do is to trace which wire it is that is sending that signal, and then tapping into it. (Note – a digital controller will be far more complicated than an analog controller).

You have to keep three things in mind, however:

1) timing: there is likely to be a time delay of several seconds between the time the controller sets to GREEN and the light actually changes. And it will take the spikes a second or two to retract. So you have to build in some sort of anticipator to pre-lower the spikes – otherwise people will start driving when they see the green, even if the spikes have not retracted.

2) emergency vehicles: how will you deal with the need of ambulances and fire trucks, that frequently run red lights to get to their destination? Similarly, how will you deal with the occasions where police are directing traffic (perhaps due to an accident nearby) and are not heeding the traffic signals?

3) people who run red lights – will you by definition puncture the tire of anyone who runs a red light? Bad idea.

I think this is an idea that technologically can be achieved – but you have to deal with other situations.

And in the US at least, there would be huge legal and regulatory hurdles.

I think that is a great idea. Shredded tyres are probably the best deterrence against running a red light.
And to prevent public service vehicles to have their tyres shredded in the case of an emergency, they could install a special radio beacon tied to the respective car’s siren to óverride the system temporarily.

Are you thinking of the systems they have in some rental car parking lots? They exist but are not used on roads.

@ragingloli Because the literal enforcement of the law may as well be automatic violent enforcement with no human oversight? What about ambulances, for just one example?

@Zaku
I addressed that already.

@ragingloli Oh, so you did. Sorry, it was rude of me to black out and not read the rest of your answer.

I think a community has a right to have such things, as long as the community actually votes for it, and as long as there are places those of us who don’t want them can move away to. I already feel violated enough by all the traffic cameras, and logging of everyone’s license plates, and radar and lidar used to detect trivial speed infractions, and security cameras everywhere, and so on.

I’m with @ARE_you_kidding_me. It’s a bad idea. In some situations, even for civilians, running a red light is the best option you’ve got.

I was once stopped at a red light, at an intersection with good visibility, and no vehicles were crossing. When I looked in the mirror though, there was a semi-trailer braking so hard smoke was coming from the tyres, and the trailer was beginning to jack-knife behind him. In that moment, my best option was to run the red light. Can you imagine if there were spikes attached to the red light? It’s a really bad idea.

Running a red light causes potential accident and blocks an intersection. Not a great idea unless this is in some sort of private drive out of a parking lot. I’ve seen this at rental car parking lots but the spikes triggered manually and not automatic.

I read a review a while back of the BAC Mono. For those that don’t know, this is an open top, single seat sports car for the road. The scene opened with the journalist sitting at a red light, while a mentally ill person screamed “you’re not batman” at him, and began to throw bottles at his head.

Again, sometimes running a red light is a good idea.

@FireMadeFlesh Yeah, or the time I was stopped in traffic in some crazy suburb, and some very unpleasant intimidating lowbrow types got out of their car and started sauntering between the cars. I didn’t run a light, but I got ready to move, and it would have stunk if there was a spike strip ready to add another violent threat to the situation.

Physical attempts to enforce the law automatically, especially by dangerous means such as spike strips (or, say, razor wire atop mostly-pointless fences) seem like usually bad ideas overall. They say to me that someone’s excessively fearful and has control issues and are willing to harm others to quell their own conditions which would be better soothed by therapy. (Nothing personal, to anyone who thinks auto spike strips sound cool.)