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PostPosted: Wed Oct 10, 2007 04:55 
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Quote:
Speed camera lies, says inventor

Oct 9 2007 by Jule Wilson, The Journal


Link to article

THE brains behind a new mobile phone system has claimed the device got him off a speeding charge after it showed he was doing 12mph less than police claimed.

Dr Phillip Tann, 45, of Harton Lane, South Shields, appeared before magistrates in Sunderland after police said he had been doing 42mph in a 30mph limit.

But he says his global positioning system showed he was doing less than 30.

His prosecution has now been discontinued after the police officer who had handled the speed recording equipment in Dr Tann’s case retired from Northumbria Police and was unwilling to attend court.

But Dr Tann says the accuracy of his technology cannot be denied after having “proved” the police camera wrong. The businessman, who began developing the new tracking system three years ago, said the device was not dissimilar to an aircraft’s black box.

And he said that after his victory, it could now be used to challenge speed cameras, among several other potential uses.

His claims have been adopted by one organisation campaigning for speed cameras to be scrapped.

Paul Smith, founder of SafeSpeed.org.uk, said in the light of Dr Tann’s case: “We demand that the Home Office withdraws laser speed meters immediately.

“We know they make mistakes; I’ve seen it happen with my own eyes during independent testing, and I’m quite sure the Home Office knows too.

“Millions of motorists are being convicted by these devices with evidence that can never be beyond a reasonable doubt. It’s a tragedy for justice and a tragedy for road safety. Quite apart from the errors with the equipment, speed cameras have not made our roads safer and we believe they must be scrapped.”

But a spokesman for Northumbria’s Safer Roads Initiative, which operates Northumbria Police speed cameras, said it was impossible for Dr Tann’s measurement to be correct.

Jeremy Forsberg said: “Dr Tann was travelling at 42mph when the camera caught him. That is a fact. GPS works as the crow flies and we use laser equipment with an accuracy level of a millisecond. We also back it up with video recording to half-a-second accuracy.”

Dr Tann – whose company Autopoietic Systems (Tann Ltd) is at Birtley, Gateshead – is now in talks with several major investors with a view to marketing the technology, most likely for use in monitoring the whereabouts of children or patients with conditions such as Alzheimer’s disease.

He said the system could measure data over distances of less than half a metre, compared with traditional GPS devices which work on distances of about 10 metres. But Mr Forsberg insisted Dr Tann’s evidence simply suggested an average speed over a certain distance, rather than an accurate reading of the speed at which he had driven past the camera.
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PostPosted: Wed Oct 10, 2007 06:58 
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Quote:
Jeremy Forsberg said: “Dr Tann was travelling at 42mph when the camera caught him. That is a fact. GPS works as the crow flies and we use laser equipment with an accuracy level of a millisecond. We also back it up with video recording to half-a-second accuracy.”


Typical. When your gravytrain is threatened tell some lies. :x

GPS absolutely does not work 'as the crow flies'. As everyone with any brains who isn't inclined to tell lies to make one's case better knows, GPS simply calculates and plots your position at any given time. Most systems do that calculation several thousand times or more per second. When you move your new location is instantly calculated and your movement is recorded from where you were a thousandth of a second ago. Thus, your speed and direction can be recorded and calculated with great precision.

This Mr. Forsberg is a grade A arse.


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PostPosted: Wed Oct 10, 2007 07:39 
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Several thousand times a second? No. Every second or two? Yes - and that still mneans following the curves rather than as the crow flies.


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PostPosted: Wed Oct 10, 2007 12:18 
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Jeremy Forsberg wrote:
Dr Tann was travelling at 42mph when the camera caught him. That is a fact. GPS works as the crow flies

Not necessarily. If he was using Doppler Shift then it will be accurate at any given instant. Even if not, curving around such that at 42mph, over 0.34 sec (6.4 metres), while the average over 41m (source unconfirmed edit: seen it on Sky News online) is 30mph will require such a sharp arc that the operator simply won’t be able to track the vehicle; in fact the vehicle wouldn’t have the traction to perform such a feat. It would certainly show up on the viceo.

Jeremy Forsberg wrote:
and we use laser equipment with an accuracy level of a millisecond. We also back it up with video recording to half-a-second accuracy.”

The guy clearly has no idea what he is talking about. To use his own use of physics against him: a millisecond at the speed of light = 300km, that doesn’t sound reliable to me.

How's about they release the video for independent scrutiny [doesn't hold breath]

Jeremy Forsberg wrote:
But Mr Forsberg insisted Dr Tann’s evidence simply suggested an average speed over a certain distance, rather than an accurate reading of the speed at which he had driven past the camera.

'Suggests' doesn’t mean that it 'is', as I have already highlighted above. Even if not, +/- 0.5m twice over 41m gives a maximum error of 1/40 = 2.5%. That doesn’t nearly account for the error achieved.

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