On Thu, 8 Jul 2004, Major Variola (ret) wrote: > 1. I've seen adverts for linear sensors which image the bottoms > of cars as they drive over. Sort of a scanner where the paper > does the moving. Installed in the road.
Come to think of it, yes, the "road" within the tollbooth gate was a bit raised, so there could well have been sensors underneath it. Might as well add all the sensors you can afford, after all any cars going through the gate are a captive audience. > 2. There are companies developing sensors that bombard > your car with neutrons (don't have to open the trunk), > and detect the N from the temporary neutron-activated gamma emissions. > > 3. Obviously license plate OCR is trivial. Natch. I also did see the big red IR lamps behind, but that's old school in almost any toll booth. > 4. I've read papers on recognizing vehicles by their inductive > signature as they drive over regular road sensors. This was > to passively measure road speed for traffic control. The idea > is that a VW Beetle has a different inductance vs. time than > a Ford-250 or an 18 wheeler. You correlate between > roadloops at known distances apart and infer road speed. Or you OCR license plates which is mostly trivial these days, or a combination of both. Then again, for upstate NY, you actually get a card for NYS Throughway and pay when you exit at another tollbooth. Card has a magnetic stripe, and shows the entry point on the throughway. So there are obviously other less expensive ways to do just that. Add cameras with timestamps at each tollboth and a way to keep track of which card was where and you've got a verifiable robust tracking system. > 5. One could call terahertz "hard RF" in same way that hard x-rays > bleed into soft gammas. But calling anything "hard" implies danger, > and we mustn't scare the proles. Perhaps soft IR is better. :) Sort of like spammers calling their trade "targetted mails" or "opt-in" Heh, would be funny if the 4am NINJA SWAT raid teams painted happy faces on their helmets and say "Have a nice day" as they shoot. > Whatever, its still pornography if the resolution is high enough. What was that quote?... "tits or nukes, it's all just bits on the wire" I also recall reading recently about those colored plastic/glass embedded in the road bumps that reflect light (so you can see your lane better?) are being retrofitted with cameras in them and set at an angle to read the license plate and measure speed as you drive over them by some company. Bah, wetware memory sucks. :(