junk@ur-tut.UUCP (Jan Vandenbrande) (02/20/86)
... Is it true that "Laser Pulse" devices are being used to measure vehicle's speed for speed enforcement purposes? Instead of using radar frequencies, a laser pulse reflected from the car is used. Naturally, a radar detector will not pick up such a laser pulse. Has anybody heard of such a rumor before? Or has anybody heard of speed enforcement methods other than the ones in use now? (NB. supposedly it's an infrared laser beam) Jan.
rmrin@inuxa.UUCP (D Rickert) (02/24/86)
> ... > Is it true that "Laser Pulse" devices are being used to measure > vehicle's speed for speed enforcement purposes? > Instead of using radar frequencies, a laser pulse reflected from > the car is used. Naturally, a radar detector will not pick up such a > laser pulse. > Has anybody heard of such a rumor before? Or has anybody heard of > speed enforcement methods other than the ones in use now? > (NB. supposedly it's an infrared laser beam) > > Jan. CAR WARS???? -- You are Beautiful, Dick Rickert my manufactured love;- AT&T CPL but it is only Svengali, Indy, IN talking to himself again. Reward is its own virtue!
jim@sivax.UUCP (Jim Bauman) (02/24/86)
> ... > Is it true that "Laser Pulse" devices are being used to measure > vehicle's speed for speed enforcement purposes? > Instead of using radar frequencies, a laser pulse reflected from > the car is used. Naturally, a radar detector will not pick up such a > laser pulse. > Has anybody heard of such a rumor before? Or has anybody heard of > speed enforcement methods other than the ones in use now? > (NB. supposedly it's an infrared laser beam) The Japanese (who else) are working on it, but don't expect to see it here for several years. How could the county mounties justify junking all their KR-11's for the sake of a laser unit? The cost would be horrendous, and all that just to nail people with Escorts and Buzzfusters? Naaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa!
larry@kitty.UUCP (Larry Lippman) (02/25/86)
In article <378@ur-tut.UUCP>, junk@ur-tut.UUCP (Jan Vandenbrande) writes: > Is it true that "Laser Pulse" devices are being used to measure > vehicle's speed for speed enforcement purposes? > Instead of using radar frequencies, a laser pulse reflected from > the car is used. Naturally, a radar detector will not pick up such a > laser pulse. > Has anybody heard of such a rumor before? Or has anybody heard of > speed enforcement methods other than the ones in use now? > (NB. supposedly it's an infrared laser beam) Yes, it's true. About a year ago, I saw an engineering prototype of such a device, which uses an infrared injection laser diode as the light source. In addition, there was an optical sight (with cross-hairs, :-) ) which ALSO had a beam splitter connected to a CCD array video camera - the intention being to record the offending vehicle on videotape for evidentiary purposes. The electronics in the unit provided a superimposed time/date display along with speed AND RANGE for the video recorder. The princples of low-power laser ranging have been well-developed over the last ten years for use in surveying instruments. The use of such designs for speed measurement purposes is almost trivial. The only stumbling block for law enforcement use has been to develop a unit low enough in cost; to be competitive with radar (it will still cost more, though), such a laser unit must cost << $ 5K. A target price for a unit without the video camera is around $ 2K. I can't wait to see the reaction of the general public... ==> Larry Lippman @ Recognition Research Corp., Clarence, New York <== ==> UUCP {decvax|dual|rocksanne|rocksvax|watmath}!sunybcs!kitty!larry <== ==> VOICE 716/741-9185 {rice|shell}!baylor!/ <== ==> FAX 716/741-9635 {G1, G2, G3 modes} duke!ethos!/ <== ==> seismo!/ <== ==> "Have you hugged your cat today?" ihnp4!/ <==
hsu@eneevax.UUCP (Dave Hsu) (02/26/86)
In article <212@sivax.UUCP> jim@sivax.UUCP writes: >> ... >> Is it true that "Laser Pulse" devices are being used to measure >> vehicle's speed for speed enforcement purposes? >> ... >The Japanese (who else) are working on it, but don't expect to see it >here for several years. How could the county mounties justify junking >all their KR-11's for the sake of a laser unit? The cost would be >horrendous, and all that just to nail people with Escorts and Buzzfusters? > >Naaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa! Gee, I wonder what percentage of Escort owners falls into the `Frequent Transgressor' category...(hey look, it was worth it to justify the bucks for a detector, was it not? if you don't amortize the cost of the detector over its lifespan, do you think it's saved you money yet?) :-) -dave -- David Hsu Communication & Signal Processing Lab, EE Department <disclaimer> University of Maryland, College Park, MD 20742 hsu@eneevax.umd.edu {seismo,allegra}!umcp-cs!eneevax!hsu "Godzilla has been spotted in Sector 5!"
fbr@utastro.UUCP (Frank Ray) (03/01/86)
Never fear. If the fuzz are beaming electromagnetic energy at you, it can be detected. Different wavelength, perhaps, different durations, but there will be a market, then, for IR speed trap detectors. It's still line of sight, but with fewer ways to detect with echos. Probably the big question will be whether an IR detector for this purpose will be regulated (and presumably legal under federal interpretation) by the FCC. fbr@utastro.UUCP
larry@kitty.UUCP (Larry Lippman) (03/05/86)
In article <442@utastro.UUCP>, fbr@utastro.UUCP (Frank Ray) writes: > Never fear. If the fuzz are beaming electromagnetic energy at > you, it can be detected. Different wavelength, perhaps, different > durations, but there will be a market, then, for IR speed trap > detectors. It's still line of sight, but with fewer ways to > detect with echos. How is a detector going to sense a few millimeter diameter spot of IR energy aimed at a random area on a car? Like a bumper, door, grille, etc.? > Probably the big question will be whether > an IR detector for this purpose will be regulated (and presumably > legal under federal interpretation) by the FCC. No way will there be FCC regulation. OSHA, perhaps, just to certify that the energy level is harmless. ==> Larry Lippman @ Recognition Research Corp., Clarence, New York <== ==> UUCP {decvax|dual|rocksanne|rocksvax|watmath}!sunybcs!kitty!larry <== ==> VOICE 716/741-9185 {rice|shell}!baylor!/ <== ==> FAX 716/741-9635 {G1, G2, G3 modes} duke!ethos!/ <== ==> seismo!/ <== ==> "Have you hugged your cat today?" ihnp4!/ <==
jordan@noscvax.UUCP (Martin C. Jordan) (03/11/86)
I have a question concerning the practical implementation of
an IR/visible laser pulse to speed enforcement. Laser radiation will
either be reflected, absorbed, or backscattered at the surface of the
oncoming vehicle. Unless the vehicle is a MACK truck, the reflected
component will be reflected at some angle AWAY from the direction of
arrival. With the "wedge" shape of current sports cars, this is probably
an upward direction. The amount absorbed will vary with paint composition,
but those of us with lots of chrome will absorb little, increasing our
likelihood of detection. Backscatter will also be a function of surface
composition (paint, chrome, bra material, etc.), but should contribute
little to the returned signal. In short, the laser device is like shooting
pool, where the cue ball comes right back at you no matter what the
angle of your bank shot.
Any counters to this hypothesis? If not, I shall sleep easier
knowing Buford T. Justice will be denied his cut of the Star Wars' pie.
Keep on Truckin'
Martin Jordan
'57 CHEVYS ...... FOREVER!!!!!west@calgary.UUCP (Darrin West) (03/13/86)
In article <252@noscvax.UUCP>, jordan@noscvax.UUCP (Martin C. Jordan) writes: > > I have a question concerning the practical implementation of > an IR/visible laser pulse to speed enforcement. Laser radiation will > either be reflected, absorbed, or backscattered at the surface of the > oncoming vehicle. ... The amount absorbed will vary with paint composition, > but those of us with lots of chrome will absorb little, increasing our > likelihood of detection. Backscatter will also be a function of surface > composition (paint, chrome, bra material, etc.), but should contribute > little to the returned signal. The reflectivity and absorption of any elecromagnetic radiation is a function of the wavelength of the light used. (visible or not). If a fine enough wavelength is used, it would reflect off the microscopic uneven-ness of the the paint or chrome. The trouble with this is that the smaller the wavelength, the more energy is involved. Going the other way may also get the job done. Bouncing a long wavelength off something is highly successful. It is known as radar. :-) Let us hope they don't use visible light (lasers tend to blind people when used without the proper discretion). If you can sense radar waves, you should be able to sense any other EM wave that is not overpowered by background "noise". All you need is the same device that is in the original sensor. The only problem is where to mount it (them). Keeping a tight beam will likely have the problems mentioned by M Jordan, and will also put a good drain on a battery. Darrin West. CPSC Grad Student.
fbr@utastro.UUCP (Frank Ray) (03/14/86)
In article <252@noscvax.UUCP>, jordan@noscvax.UUCP (Martin C. Jordan) writes: > > I have a question concerning the practical implementation of > an IR/visible laser pulse to speed enforcement. Laser radiation will > either be reflected, absorbed, or backscattered at the surface of the > oncoming vehicle. Unless the vehicle is a MACK truck, the reflected > component will be reflected at some angle AWAY from the direction of > arrival. > ... > Martin Jordan Now suppose you were going to design an IR speed gun. Wouldn't you want the beam large enough to insure its successful operation in practice, when used by the average traffic cop? True, one could design a system only sharpshooters could use, with a telescopic sight. I suppose the states could also require that each motor vehicle carry a laser reflector on the front, for the sharpshooters to shoot at. Corner cubes would work fine in that regard. Think of the new markets. Some useful things may come out of this laser research, actually, such as automatic highways. "Sorry I'm late getting home, honey. The highway crashed." How about a LASER DETECTOR BRA? Come on you fuzz, shoot me. fbr
larry@kitty.UUCP (Larry Lippman) (03/15/86)
In article <252@noscvax.UUCP>, jordan@noscvax.UUCP (Martin C. Jordan) writes: > I have a question concerning the practical implementation of > an IR/visible laser pulse to speed enforcement. Laser radiation will > either be reflected, absorbed, or backscattered at the surface of the > oncoming vehicle. Unless the vehicle is a MACK truck, the reflected > component will be reflected at some angle AWAY from the direction of > arrival. ... > Any counters to this hypothesis? If not, I shall sleep easier > knowing Buford T. Justice will be denied his cut of the Star Wars' pie. No surface of a motor vehicle will be such a perfect reflector or absorber such that sufficient DETECTABLE modulated IR energy will NOT be returned to the laser device. This statement is based upon the output power/detector sensitivity characteristics of one prototype device which I have seen that has a nominal range of 1,000 meters in clear air. ==> Larry Lippman @ Recognition Research Corp., Clarence, New York <== ==> UUCP {decvax|dual|rocksanne|rocksvax|watmath}!sunybcs!kitty!larry <== ==> VOICE 716/741-9185 {rice|shell}!baylor!/ <== ==> FAX 716/741-9635 {G1, G2, G3 modes} duke!ethos!/ <== ==> seismo!/ <== ==> "Have you hugged your cat today?" ihnp4!/ <==
stan@clyde.UUCP (Stan King) (03/18/86)
Aren't all cars required to have visible-light corner reflectors installed? Will these also return infra-red light towards the vicinity of the light source? If so, it seems like one of Buford's problems is already solved. -- Stan King phone: 201-386-7433 Bell Labs, Whippany, NJ Cornet: 8+232-7433 room 2A-111 uucp: clyde!stan