stealth car

Ok, not technically military nor a weapon but this seemed like the best fitting forum given the general nature of this technology.

If you built a "stealth car" would it trigger police speed cameras?

It depends how those cameras were activated. Most likely motion detection using infrared or a laser.

If thats the case you would need to make your car as cool as everything around it. Or in the case of a laser, make the care reflective like a mirror.

But, if it uses a sonar or radar, you would need to deflect the signal. I cant imagine what a car would look like all "stealthed out" like an F-117.

Or maybe some sort of active protection that altered the camera's timing or something, or maybe some sort of very bright light that messed with the camera's ability to get a clear picture, blind it!

posted by skippytjc: “It depends how those cameras were activated. Most likely motion detection using infrared or a laser. If that’s the case you would need to make your car as cool as everything around it. Or in the case of a laser, make the car reflective like a mirror [angled away from the source like an F117A on wheels]. [My comments in brackets]

I don’t believe there is any reasonable technology that can defeat either of these measuring devices.

But, if it uses a sonar or radar, you would need to deflect the signal. I can’t imagine what a car would look like all "stealthed out" like an F-117 . . maybe some pro-active protection to altered the camera's timing . . or maybe some very bright light that messed with the camera's ability to get a clear picture, blind it! [Edited by Don W]

A few years ago - maybe 20 - R&T mag and C&D mag had classified ads. One ad appeared in both mags for a long time. It was a build-it-yourself ECM device. As in the old time Heath kits. All the radars work on the same principle - a timer to measure the time lapse between transmission of the signal and the time the reflected signal is received back. Speed is a direct function of time. Although angles do figure into more exact calculations, the short distance needed to measure a car is inconsequential. Assume the radar gun puts out a 5,000 watt signal for 1/10,000th of a second. (If the gun pulses 100 times a second when operated, the “average” power of the gun is a mere 2 watts.) The strength of any electromagnetic radiating signal is inversely proportional to the square of the distance between the source and the observer.

Example: if a car at 50 feet distance produces a return signal of 100 microwatts, then a car at 100 feet distance will produce a return signal of only 25 microwatts. The advertised device produced an output signal of about 100 microwatts. This signal was strong enough to override the reflected signal of the radar gun. By varying the phase of the output signal, the ECM radar cold cause the radar gun to give a false reading as to speed. It was also illegal to have an unlicensed transitting device. A Federal crime.

The device offered the operator the capability to set his or her speed. This has obvious limitations. Ir you drive a Porsche 930, and if 100 mph is your preferred cruising speed, and if you set your ECM set to 65 mph, any cop is going to know there is something amiss. Most cops learn to judge a cars speed within 2-3 mph after time on the radar gun. So, the ECM would be ok if you were running 73-74 in a 70 mph zone, and had the ECM set on 70.

Older radar guns had such a wide beam that the gun could only measure the largest physical object’s speed when two or more vehicles were under the gun. By the 1990s, the beams were narrow enough that cops could pick out your car running alongside an 18 wheels. I crowd the limit by using my cruise control set at +4 over the posted limit. 3 vehicles out of 5 will pass me, but what the hey? I don’t need the points. And I can buy lottery tickets with the cash saved.


[edit on 4/28/2006 by donwhite]

What's wrong with an F117 on wheels, with mirrors lasers to blind spped camera's and radar jammers it would be awesome and dont forget chaff!!!!!!! i know this is an rc car but just make a larger version and cool the exhaust its would be awesome especially at night ........no cops!!!!!1111

Planeman,

>>
Ok, not technically military nor a weapon but this seemed like the best fitting forum given the general nature of this technology.
>>

Stealth as applied to vehicles I envision as being something like this-

www.aeronautics.ru...

www.aeronautics.ru...

combined with this-

www.dtic.mil...

In that the simplest way to maintain visual anonymity is to destroy the signature outlines within a block shape of entirely different form and texture.

And the best way to extend this to secondary RF levels is to fit bluff secondary appliques (which may also function as armor) that more or less eliminate body junctions, panel-joins and at least mask design elements like wheel well cutouts and engine venting behind deep-dielectric absorbers.

Obviously, the ability to function without secondary audible propulsion noise (hybrid-electric drive) and in a terrain environment beyond that which the threat can see-or-expect you (all terrain and masted sensors) 'helps a lot'.

Because you won't be stalked by lions in the arctic. And a foot wide mast 10ft above the horizon line certainly beats a 10ft wide grille and fenders when the polar bears come looking for meat.

That said, the ultimate humiliation factor of cops and speedguns is that they force you to do in shame of being caught that which SHOULD BE a cry of freedom.
There being no fahrfugnugen factor when you are more worried about being caught than in finding out if you can physically master a vehicle at those speeds..

As such, why wish to go 100 in a 65 (I can tell you 70% of American roads, 80% of American suspensions and 90% of American drivers are not cut out for the attempt).

But 200 in a 250?

With this-

www.iicm.edu...

x.gadgetmaniac.com...

Achieving a Real sense of speed is quite possible.

Because as soon as you demand to be allowed to do something /safely/; the 'reasons why' you are forbidden from the action must be dealt with as an honest function of physics necessary to make the law inapplicable rather than 'skirted'.

Or Bra'd as the case may be.

Many high performance (low slung) vehicles of the mid 80's having adopted supposedly RAM-enhanced grill covers and mudprotectors before the switchover to LIDAR based systems rendered X-Band protection more or less useless.

To which, I can only add that 'reflective' systems only work if they are in fact scatterers of immense non-linear return efficiency. Absorbers are required to nullify Mie type speculars and I know of none which work reliably in laser bands at the linear distances typical of speed traps.

To defeat that kind of ambush-predator system, you almost need to go to a netcentric/cell countermeasure of automatic position tags based on passive reception and rebro (a variant of the 'flashing lights' warning still extended occasionally as an illegal courtesy alert) notification.

This being less of a stealth-for-you. Than a stealth-defeat mechanism against them.


KPl.