Safe Speed Forums

When revenue raised by that higher reading (as opposed to a lack of revenue collected by a reading that is under the limit) goes (directly or indirectly - exactly what path it takes is irrelevant) towards paying that operator's wages....

Well, who is talking nonsense now? The fact remains that it is in the power of the operator to continue his revenue stream even if the public are complying with the law. There is an element of doubt there to be exploited, and that potential is enough to call the ethics of all camera partnerships into question if they do not cease operations while proper, independant investigations are carried out.

JJ,

Can you confirm whether these devices are mounted inside vans, or are they fixed to tripods that are directly attached to the ground?

It is just that a "stationary" vehicle is anything but stationary, because it is effectively a large mass mounted on springs, and will move in response to external stimulation such as a gust of wind, the operator moving around, or the air and ground displacement of vehicles moving past.

A significant displacement is quite possible in these scenarios, and it is possible to get a relative forward movement that will give an incorrectly high reading.


As a secondary point, there are enough of us around that believe that we have been deliberately entrapped into a speeding conviction (in my case by a pair of Police cars), and there was recently some very convincing undercover documentary evidence that showed that Parking enforcement was very much target based, and failure to meet the target resulted in loss of job. For the vast majority of the general public it appears obvious that a camera operator will have some sort of incentive to attempt to acquire higher readings. While never official policy (it wasn't for the Parking Attendants either), it is exactly what happened on the ground, and when an organisation has been clearly shown to be very selective when it comes to publishing data it is not surprising that the public believes the worst.

Safe Speed issued the following PR at 9:33 this morning:

PR239: Laser speed meters untrustworthy

News: For immediate release

BBC TV programme "Inside Out" have been testing a laser speed meter, and will
broadcast this evening a film showing two laser speed meters pointing at the
same vehicle showing markedly different speeds. The regional programme will air
in London and BBC South West region this evening at 7:30.

Under UK law, offences must be proven 'beyond a reasonable doubt'. The BBC film
illustrates a potentially commonplace error. Millions of drivers have been
convicted with unsound evidence, and many prosecutions are ongoing.

The error in question is known as 'slip error'. It happens when the aiming
point of the beam moves across the target vehicle. This works because laser
speed meters do not directly measure speed. Instead they take a series of
distance measurements. If the aiming point moves along the target vehicle the
change in distance of the aiming point adds to or subtracts from the true speed.

Sources tell us that the Home Office did not test for this error before issuing
type approval.

Paul Smith, founder of the Safe Speed road safety campaign
(www.safespeed.org.uk) said: "I have seen the film and it is shocking. No
wonder we get a steady stream of indignant motorists complaining to us that
they know for sure that they were not driving at the speed of which they are
accused. And no wonder that people have christened the most common laser speed
meter the 'dodgyscope'.

Paul continues: "I am 100% certain that these devices are not suitable for
gathering legal evidence of vehicle speeds. They make mistakes and the BBC
film proves it. The Home Office must immediately suspend type approval on
these devices pending a full investigation. Millions of drivers will be
entitled to refunds, licence points removed and in some cases a large amount of
compensation."

At a very rough estimate, over 5 million drivers have been convicted on the
basis of laser speed meter evidence in the last 5 years. The fines refund alone
will run to £300 million. This is a disaster of epic proportions."

"Paul concludes: "With £300 million pounds at stake, we should expect some
fierce resistance. But resistance is futile. The 'dodgyscope' is proved to be
dodgy.

<ends>

Notes for editors
=================

Thumbnail image attached.



Higher res version (1600*1200):
http://www.safespeed.org.uk/pr239.jpg




Complete BBC PR:
================

'Slipping' speed guns may result in innocent South West drivers being fined

Strictly embargoed until 09.00 12/9/05

Claims that a hand-held speed gun - used by Police and Camera Safety
Partnerships across Devon and Cornwall - can give an inaccurate reading by
'slipping' are made by BBC South West's Inside Out programme tonight at 7.30pm
on BBC ONE.

The 'slipping' effect is caused when the gun's infra-red pulses are disrupted
by the operator moving the beam down the side of the vehicle instead of keeping
it steady. When this happens the gun can be effectively tricked, interpreting
the movement of the beam as speed, and the length of the car is added to the
distance actually travelled.

With the LTi 20-20 speed gun being used across Devon and Cornwall this could
lead to South West motorists receiving unfair fines.

In tonight's programme Dr Michael Clark, independent consultant to the traffic
and communications industries, commenting on the effect of a potential
'slipping' error, says: "If someone’s doing just below 70 mph on a motorway
that puts him up in the 90’s and they’re going to be done by the police for
sure."

Professor of engineering and author John Brignell believes that for an
operator, pointing the gun at a car 500 meters away, the movement needed to
slip off the number plate and down the side of a vehicle is minute. He says:
"Very roughly, without doing any calculations, we are talking about the camera
moving about the thickness of a human hair."

And even in an experiment carried out by Inside Out presenter Samantha Smith,
pointing the gun along the side of a stationary car, the device registered a
speed of six mph. When the test was then carried out on a truck travelling at
about 30 mph, a false result was obtained 7 out of 22 times. Wrong speeds of up
to 56 mph were displayed by the gun.

Teletraffic, the importers of the UK approved LTi 20-20 speed camera, claim it
is impossible to register a false reading from a moving target. The company
adapts the American LTi 20-20 guns to follow British specifications.

Presenter Sam Smith says: "Unfortunately Teletraffic, the Police and the Home
Office declined to take part in the programme which meant we were unable to
obtain a British version of the LTi 20-20 for our experiments, so Dr Clark
simply proved such misreadings can happen with the American speed gun too."

The Association of Chief Police Officers claim the experiment was 'misleading'
as the UK approved speed gun uses different 'error-trapping' software.

Yet a report, obtained by Inside Out and written by Frank Garratt, Managing
Director of Teletraffic, strongly suggests both versions of the LTi 20-20 are
the same. His report says the gun used by British Police is identical to the
version used by NASA. And NASA then told Inside Out that the version they use
is the American version. All of which seems to suggest that the UK and American
speed guns are identical.

Using the Freedom of Information Act the Inside Out investigation has also
discovered that the Home Office does not test for the 'slip effect' as part of
the approval process for these devices.

Inside Out: Monday 12th September, 7.30pm on BBC ONE

Note to Editor:

The LTi 20-20 speed gun is used by the Police and Camera Safety Partnerships
across the UK.

For further information contact:

[removed]

<end of BBC PR>

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

We there you go - unless you use the most solid of tripods firmly mounted into the ground and in a possition that doesn't get ground vibrations from say a pothole, these devices can get a slip effect just from localised movement such as a gust of wind.

Worse. The operator has to move it to use it...

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

If that's the case, then I am puzzled by what's happening in this video.

http://pepipoo.com/Case_Files/documents/CF11_PVA.rm

_________________
Useless laws weaken necessary laws.

Looking at that bike video it seems the actual point of aim was all over the place, especially when the bike was closer. Even at the end of the clip it seemed they were having trouble pointing at the bike (because of the reducing angle perhaps?) though at over 600 metres the bike appeared a lot smaller. Presumably the scamerati could minimize the potential for slip by only enforcing at extreme range, say half a mile, with the tripod fixed onto the ground, which means they wouldn't have to move it at all. Of course, then they'd struggle to justify a pre-formed opinion that a vehicle was speeding before the measurement was taken. Damn shame.

_________________
Make everything as simple as possible, but not simpler - Einstein

I forgot to mention that the guy on the bike was being prosecuted for doing 107 mph.

_________________
Useless laws weaken necessary laws.

Gadgets are only as good as the operator using them - and maintenance of said gadget. We use these gadgets on occasion - but we don't just aim at anything which moves ) - used to confirm a professional opinion that person is way over the limit.

Shall wait till seen documentary report - though my RT describes a different topic for this programme.

_________________
Take with a chuckle or a grain of salt
Drive without COAST and it's all your own fault!

A SMILE is a curve that sets everything straight (P Diller).

A Smiley Per post
FINES USfor our COAST!

Approach love and cooking with reckless abandon - but driving with a smile and a COAST calm mind.

Hi guys!

Some interesting and heated debate in this thread.

I think I can contribute with first of all an explanation of how the LTI 20.20 works.

First of all the error codes.

E01 - meant that no reflected laser light returned to the device. Typically you will get this if you point it to the sky. The device will expect to see a reflection within a given period of time and if it doesn't it generated E01.

E02 - from the few samples, the device calculates an expected position of the target using a straight line velocity curve. It then collects further samples. Samples which are outside of the expected position plus a given tolerance are rejected. The sample set is just over 40 samples, of which 35 must be within the tolerances just described. You can typically demonstrate this error by moving the laser from one object to the other.

E03 - The device now has a sample set. An average speed is calculated using a least squares method (as described in the published patents). Each sample is then compared against this average speed, and if out by a given tolerance then the sample set is rejected with E03. Also if a large variance is found in the *power* of the returned pulses then the sample is also rejected.


Unfortunately this method can never reject all spurious readings. Why? Because sometimes genuine sample sets look very similar to spurious sample sets and vice versa.

Therefore SLIP is possible. Of that there is no doubt.

The fact that you see E03 error messages means that the LTI 20.20 is rejecting SOME sample sets. It does not, and cannot mean that the device is capable of rejecting all spurious sample sets.

Further evidence of this can be found on the web, and in the BBC programme broadcast in February.

Given this, when you a see speed reading on the device, how can you be sure that slip was not involved. You can't. And you certainly can't prove it. How would you know slip was involved in a speed reading?

There exists evidence to show that these devices are used in enforcement sessions without being aligned correctly. At the sort of distances they are being used it only takes a tiny, possibly inperceivably amount of movement for the laser to move a great deal at distance - resulting in slip.

Misaligned devices mean that instead of the laser being tracked, following a vehicle, it is slipping on some other surface.

There exists more evidence to show that the Police, the CPS and their witnesses have then LIED to try to cover this up. This will be demonstrated in due course.

We would love to have a play with real Police equipment. But the Police seem to be dead against the idea. If any camera parternship people on here think they can arrange it, then sort it out and give us a contact number. There are plenty of experts, solicitors and media people queing up for a go. So far the Home Office/CPS/Police are saying "NO WAY". Why? Is this open society we live in?

The "expert" witness used by the CPS for the LTI 20.20 is in fact the managing director of the company that supplies them. He has no scientific or Engineering qualifications but he is an ex-Police Officer.

In time it will be demonstrated that this "expert", with a clear financial interest in the device, has mislead Courts. We are not talking about speculation here, we are talking about written, concrete evidence.

This "debacle" has done nothing for road safety. And it has served to destroy public confidence in the Police and the Legal System. In my opinion - damaging the Nation in a serious way.

It is time to stop the cover ups, the lies and the dishonesty. It is not helping anyone. And that's the real problem here. There are political issues and money involved. It's just not cricket to admit to the truth these days.

Bonzer!

The does indeed have a conflict of interests.

A private prosectution for purgery or PTCOJ anyone?

Hmmm....so you don't use mobile scamera vans then! Y'know, the ones with wheels and sprung suspension. Vans than tilt and bounce when HGVs pass them or a gust of wind blows. Platforms that move when the scamerati moves around in them farting and coughing!

JJ...you spout the most astonishing amount of cr@p.

Quote from a local scamera operator "I prefer the vans, the Galaxy has soft suspension and is bounces around a lot when lorries go past."

Anybody who has seen video of camera operations knows that the crosshair waves all over the vehicle while targetting is taking place. I can EASILY imagine it being "slipped" down the side of the vehicle during targetting, especially if "loose bolts" mean that the camera isn't pointing where the laser is

Gareth

drum

It's on in a few minutes. Watch this place go quiet for the next half hour or so. Cuppa time.

Edit: Damn. Wrong region.

_________________
Make everything as simple as possible, but not simpler - Einstein

I like the bit at the end where they say "The police have told us that if anyone uses our evidence to contest a speeding ticket, they will face a much harsher penalty when found guilty".

I also don't understand why the home office wouldn't let them test a UK version of the speed gun.

The "loose bolts" was a direct reference to a case where an LTI expert (Garratt or the operator) explained that the laser wasn't pointing where the camera was because a bolt was loose.

Anyway, the programme was pretty good. You can't test UK equipment if you don't have it. It's shame the SCP didn't have an hour free to test the actual equipment, given that they can easily reproduce the errors it wouldn't have taken long.

On the programme they have the van quite close to the laser, but from a longer distance the "slip" effect wouldn't be as noticeable, and if the camera isn't pointing where the laser is it wouldn't be noticeable.

Indeed if the camera alignment check was carried out on a large road sign there is scope for them to be a long way out of alignment.

If it were me I would drop the crosshairs to the middle and then use the scope calibration function (whiny noise) against a pole and/or fence to be certain they are aligned.

Gareth

How can Magistrates refute it, it's evidence after all that questions the accuracy.

Perphaps they realise that they're gonna be refunding a hell of alot of tickets. The onus surely, is now on Her Majesty's territorial Tax collectors (The Police) to prove overwise.

I actually totally agree now ,that there is growing arrogance in the higher echelons of the police service that they consider themselves above the law. Well I guess we'll be seeing on Wednesday then!!!

Do the police decide on penalties these days? I thought that was up to the Courts?


Come, come. If they did, and all these same faults were found they would be f**ked. This is their last and final lie.

Funny how they didn't mention this difference after the first program though, don't you think?

And why would a US manufacturer give a special version to the UK that was better than the US version?