Speed Camera / Radar Question

This is a thought I have had in my head for years – quite a few years ago I worked in the WA police camera section evaluating speed & red light camera film (in the days when it was film) and I saw all sorts of attempts to beat the cameras.

I will preface this by saying that I am not advocating or encouraging law breaking, this post is one of those “I’m know I’m not the smartest guy in town, but if I can think of this why hasn’t someone smarter than me thought of it” posts.

In basic terms radar works by sending out a signal which bounces off the target and the return signal is analysed to calculate speed, location or whatever other parameter is set – IE altitude in ATC radar.
Stealth technology tries to kill the return signal – either by absorbing enough of it to effectively mute the return signal, or shaping the target (think stealth fighters) to deflect the radar, effectively send it off course.
Why has no one created a coating that can be applied to a car, maybe hidden in those car bras to absorb or deflect the signal.
Radar detectors have been around for years and while they’re now illegal in most if not all states, they can still be got.
Why has no one created an electronic gadget that will absorb the radar signal, maybe store it in capacitors as energy and dump it after a pre-set time when the car is past the radar.

Basically it comes down to cost - it costs millions to make one aircraft stealthy because there's no single magic thing that does this. A combination of shape, coating, built in electronics etc are used to make aircraft stealthy.

Maybe have a read of how complex it gets here Stealth technology - Wikipedia

Just a thought but why not simply stick to the speed restrictions and save all that money on anti-radar technology? :U

For years I regularly drove from my home to New Plymouth, a journey that took me 4 hours 15 mins under normal conditions (decent weather, no roadworks etc.) but pushing the speed over the limits where I could do it without being 'snapped'. One day I had plenty of time on my hands and decided, as an experiment, to drive all the way observing every speed restriction (and there are lots on that route). It took me 4 hours 18 mins. I also arrived less stressed. Try it on a route you drive regularly, you might be surprised.
Pete

I seem to remember an episode of Top Gear where the 3 boys had a challenge to drive across town. One could go as fast as they could, the second had to obey all speed limits and the third had to stay in a single lane all the way no overtaking allowed if stuck behind a slow vehicle. They all arrived within minutes of each other.

I used to drive the Newell Highway a lot BNE-MEL. It really p'ed me off when they had a trial where they reduced the lanes and dropped the speed limit to 100 kmh. It effectively added 2 hours driving to the 20hr trip, but it felt like 10.

You can’t “capture” a radar beam for storage and release any more than you can capture a torch beam. Stealth technology on military hardware works to reduce the return echo back to the sender by a combination of shape (minimising continuous surfaces at 90 degrees to the search direction) and absorption; but it can’t eliminate it. A big part depends on the radar beam wavelength; it’s easier to hide from a low frequency long range radar but extremely difficult to avoid a tight beam continuous wave centimetric radar. Over 50 years ago we had ship mounted tracking radars that could follow a 4-1/2” shell in flight...

A stealthy vehicle will be one that’s low and has lots of sexy curves; think of a jaguar E-type. But you then need to eliminate the radiator grill and the headlights which are almost perfect radar reflectors. Then you need to cover it in a radar absorbent material; like fake fur with variable strand lengths.

Easier to stick to speed limits!

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Originally Posted by Fuzzie

I seem to remember an episode of Top Gear where the 3 boys had a challenge to drive across town. One could go as fast as they could, the second had to obey all speed limits and the third had to stay in a single lane all the way no overtaking allowed if stuck behind a slow vehicle. They all arrived within minutes of each other.

I used to drive the Newell Highway a lot BNE-MEL. It really p'ed me off when they had a trial where they reduced the lanes and dropped the speed limit to 100 kmh. It effectively added 2 hours driving to the 20hr trip, but it felt like 10.

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Your first example is one I commonly noticed on my commute to work in the past. Traffic lights, and other "barriers" such as roadworks, bring every body back to the same or very similar total travel times.

Remove the "barriers" then its a different scenario, which is what your 2nd example is about. Sadly we need the artificial barriers - speed restrictions and the like to attempt to limit the carnage on our roads.

Many years ago, at a conference a speaker who was a transport adviser to the then QLD Beattie Gov't put forward the concept that we will never have "safer roads" due to driver behaviour. He used the accident / injury / death statistical data collected on "road improvement" to illustrate his point.

Current "problem" road has a 80 kph "design speed" it is then redesigned and constructed to 100 kph "design speed" to be a "safer design" yet the statistics quickly paint a different story. Drivers attempt to do 100 in an 80 zone, then when the road alignment is improved their behaviour trends to 120 in a 100 zone .... and the cycle continues.

He postulated that perhaps we are not being smart as he maintained that "all we are doing is increasing the severity of injuries, as the collision impact speeds are now greatly increased."

Speed advisory signs are there for a reason, speed limits too, but there will always be a proportion of the community who believe those "limits" don't apply to them.

So radar avoidance technology on our roads is illegal for a very good reason.

Here about 30 or 35 years ago, a company was making a thing to make your vehicle invisible to radar. Basically it was a radar antenna intended to reflect the radar signal back to the sender. Except the antenna was machined to induce multiple phase shifts back to the receiver. With multiple phase shifts, the receiver couldn't calculate the speed of the vehicle. Most police radar uses the doppler effect to calculate speed and with different shifts in the return signal the vehicle is ignored.

That is the good news. The bad news is that the antenna required sub, sub micron machining. This level of accuracy in the necessary machining is cost prohibitive. IIRC the cost then was about $12,000 US.

For years I did a lot of driving that was business related. I acquired a Valentine radar detector. It was supposed to be undetectable by the then radar detector detectors. I installed the Valentine between the ceiling and the rear view mirror of my pick up truck. I mounted the display on the underside of the bezel around the speedometer. The unique thing about the Valentine it that it would detect the "Instant On" radar guns when they were powered up in stand by. As you got used to driving with the Valentine you would get a weird instant on detection that was weak but continuous. I always got this alert in sufficient time to reduce speed.

I understand the need, and agree with, speed enforcement. When there are people (Like my oldest son.) that habitually try to go 40 or 50 over I'm all in favor of speed enforcement. However when speed enforcement is the main revenue source for the town council, I have an issue.

Here in California we rarely use the speedometer. We tend to drive 'Just go with the flow'. SWMBO and I were on our way to Las Vegas. SWMBO remarks that "Traffic is flowing nicely." I look at the Garmin GPS and see that we are indeed flowing nicely at 88 or almost 20 over.

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Originally Posted by smidsy

This is a thought I have had in my head for years – quite a few years ago I worked in the WA police camera section evaluating speed & red light camera film (in the days when it was film) and I saw all sorts of attempts to beat the cameras.

I will preface this by saying that I am not advocating or encouraging law breaking, this post is one of those “I’m know I’m not the smartest guy in town, but if I can think of this why hasn’t someone smarter than me thought of it” posts.

In basic terms radar works by sending out a signal which bounces off the target and the return signal is analysed to calculate speed, location or whatever other parameter is set – IE altitude in ATC radar.
Stealth technology tries to kill the return signal – either by absorbing enough of it to effectively mute the return signal, or shaping the target (think stealth fighters) to deflect the radar, effectively send it off course.
Why has no one created a coating that can be applied to a car, maybe hidden in those car bras to absorb or deflect the signal.
Radar detectors have been around for years and while they’re now illegal in most if not all states, they can still be got.
Why has no one created an electronic gadget that will absorb the radar signal, maybe store it in capacitors as energy and dump it after a pre-set time when the car is past the radar.

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The front grill on one of the early 1960s Chrysler Valiant's was a near "perfect" radar absorber. It wasn't until most, if not all of that model vehicle was removed from the fleet that the NSW Police first starting using radar. Since then, radar has gotten smarter (and been supplemented with laser ranging).
There may still be an Australian Design Rule that makes the technology you are suggesting not legal.

Back in the 1970's and 80's my brother was a mechanic and always drove cars with fully worked motors. Yes he was a bloody irresponsible rev-head and he did grow out of it eventually. :dev:

I am not sure how true it is but he swore that when the cops pointed a RADAR gun at his car, the gun picked up the speed of rotation of the highly polished stainless steel fan he had fitted to his vehicles. He said this made the RADAR read an impossibly high speed and he claims to have seen cops on the side of the road banging their RADAR guns on a post after trying to read his speed. :banghead:

I have always had my doubts that this would have worked since the speed of the fan rotation was at right angles to the beam and the forward speed of the fan was identical to that of the car, but he swore that he did not have to worry about RADARs while he had the polished fan. Even if it did work on 1970's technology I doubt it would be effective today.

On the point about camera's ,we bought a new Nissan Skyline whilst holidaying in Qld back in the 90's on the rego plates they put removable plastic covers on both front & back .When we got back to WA we had to have them removed as was deemed illegal with the quote "that the cameras would not pick up the rego number" .

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Speed advisory signs are there for a reason, speed limits too, but there will always be a proportion of the community who believe those "limits" don't apply to them.

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That's because everyone knows that they are a better than average driver.:rolleyes:

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Here in California we rarely use the speedometer. We tend to drive 'Just go with the flow'. SWMBO and I were on our way to Las Vegas. SWMBO remarks that "Traffic is flowing nicely." I look at the Garmin GPS and see that we are indeed flowing nicely at 88 or almost 20 over.

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I'd been warned about LA traffic , and found that driving as above was the most comfortable way to handle it.

From what I know about radars, is all they need to get a reading is a solid surface. Whether this is your number plates, your headlights or windscreen. So in order for your car to effectively deflect/ absorb the radar your entire car will need to be "stealthy" this would most definitely make your car not road legal as you'll either be obscuring your plates, lights or field of vision.

When I worked for the cops, I came across an image from a speed camera, the rego plate had been coated with something that made it unreadable.
When I put it through the best reader in the building (and this was in the waning days of film, the cops had to had to resort to buying second hand gear, so all the gear was of varying quality/capability) I could just make it out but it was no-where near being infringible.
The rumour was that it was hair spray but none of the cops I showed the image to would tell me what it had been coated with.

As for driving, I don't drive much now, and usually I use the cruise control, but if I have to go out of town, the first 20km's I can choose the main freeway, straight, two lanes pretty new and a 110k speed limit, or I can choose a paralell road - 100k speed limit, gravel shouldered with lots of bends and curves.
If I'm not in a hurry I take the paralell rd and if traffic and road conditions allow I sit on 110 - but, if I get caught I'm polite to the cop and after he's written me a ticket I tell him to have a nice day.
I believe in choose your actions, accept the consequences of those actions - don't blame other people for the choices YOU make.

I love driving just for the fun of it, I love bendy windy hilly roads where you have to actually have to drive, have to work, not just sit there holding the wheel straight for miles on end.
Thanks for all the replies guys, it was interesting reading your comments.

Waaaay back in '86 when I was just venturing into the wonderful world of motorbikes; "Bike" magazine in the UK did a piece of the then newly invented Gatso speed and red light cameras including all the DIY dodges that were claimed to work. They had ago at trying to defeat an SLR camera with highspeed film. The methods included:

Wrapping the plate in several layers of Gladwrap to "polarise" it... failed
Running a foglight above the number plate... partial successUsing a slaved flash unit to white-out the number plate... partial success.

The only two methods that really worked were to have a permanently filthy number plate or to run a fog light. At night. In fog. For this method I believe their conclusion was "... but if you're speeding at night in fog you deserve to get caught and fined..."

One other suggestion they posited but couldn't actually trial was to have the pillion passenger scatter handfuls of Alfoil "chaff" to confuse the Gatso's radar...:p