Busted with Laser? Read on !!
09-14-2005, 03:47 AM
#22
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Originally Posted by Louie928
Nicole
Think about a small piece of lead about the size of a pencil eraser. Now think about that piece of lead smashing into the speed camera at about 1000 feet per second velocity. The camera fails.
Think about a small piece of lead about the size of a pencil eraser. Now think about that piece of lead smashing into the speed camera at about 1000 feet per second velocity. The camera fails.
Thanks for clarifying!
09-14-2005, 08:53 AM
#23
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Originally Posted by fraggle
speed cameras generally fail in the US due to heavy lead contamination... at least they do out west here.
09-14-2005, 01:40 PM
#24
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BBC pointed out that there's no difference between the US and British versions. Here are the BBC and SafeSpeed press releases in full:
================
'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:
John Ramsden, BBC Bristol Press Office, 0117 974 7472
Dimitri Houtart
Producer
BBC South West
01752 234 557 (01 34557)
dimitri.houtart@bbc.co.uk
<end of BBC PR>
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
----- Original Message -----
From: "Casey Raskob III" <speedlaw@verizon.net>
To: Ivan <ma@motorists.org>, "Activists List" <NMA-Activist@yahoogroups.com>
Subject: Re: [NMA-Activist] Laser error
Date: Wed, 14 Sep 2005 10:00:44 -0400
I recently installed a Blinder on my car......thanks for this one. I've
never seen this error reported in the US stuff.
casey
----- Original Message -----
From: "Ivan" <ma@motorists.org>
To: "Activists List" <NMA-Activist@yahoogroups.com>
Sent: Tuesday, September 13, 2005 10:33 AM
Subject: [NMA-Activist] Laser error
The BBC program "Inside Out" tonight will air results of tests of
one of the most popular laser speed detection guns used by police
forces in the US and UK. In the program, a pair of American
specification LTI 20-20 guns, manufactured by Laser Technology
Inc. of Colorado, point at the same moving vehicle but record
substantially different speeds.
The source of the error is well-known. When the aiming point of
the laser gun, which is designed to be hand-held, moves or "slips"
across the target vehicle, an extra distance is either added to or
subtracted from the speed calculation. A tiny movement can add up
to a substantial difference. Engineering Professor John Brignell
describes the amount of motion needed to cause a slip error at a
distance of 500 meters: "Very roughly, without doing any
calculations, we are talking about the camera moving about the
thickness of a human hair."
The hosts of the BBC program were able to clock a stationary car
at 6 MPH. In tests of a moving vehicle, the laser gun produced
erroneous readings almost a third of the time, displaying speeds
that were off by as much as 26 MPH.
The devices can be upgraded and used as mobile speed cameras,
particularly in the UK where an estimated five million drivers
have been convicted based on laser speed readings over the past
five years.
"I am 100 percent certain that these devices are not suitable for
gathering legal evidence of vehicle speeds," said Paul Smith,
founder of the Safe Speed road safety campaign. "They make
mistakes and the BBC film proves it. Millions of drivers will be
entitled to refunds, licence points removed and in some cases a
large amount of compensation."
================
'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:
John Ramsden, BBC Bristol Press Office, 0117 974 7472
Dimitri Houtart
Producer
BBC South West
01752 234 557 (01 34557)
dimitri.houtart@bbc.co.uk
<end of BBC PR>
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
----- Original Message -----
From: "Casey Raskob III" <speedlaw@verizon.net>
To: Ivan <ma@motorists.org>, "Activists List" <NMA-Activist@yahoogroups.com>
Subject: Re: [NMA-Activist] Laser error
Date: Wed, 14 Sep 2005 10:00:44 -0400
I recently installed a Blinder on my car......thanks for this one. I've
never seen this error reported in the US stuff.
casey
----- Original Message -----
From: "Ivan" <ma@motorists.org>
To: "Activists List" <NMA-Activist@yahoogroups.com>
Sent: Tuesday, September 13, 2005 10:33 AM
Subject: [NMA-Activist] Laser error
The BBC program "Inside Out" tonight will air results of tests of
one of the most popular laser speed detection guns used by police
forces in the US and UK. In the program, a pair of American
specification LTI 20-20 guns, manufactured by Laser Technology
Inc. of Colorado, point at the same moving vehicle but record
substantially different speeds.
The source of the error is well-known. When the aiming point of
the laser gun, which is designed to be hand-held, moves or "slips"
across the target vehicle, an extra distance is either added to or
subtracted from the speed calculation. A tiny movement can add up
to a substantial difference. Engineering Professor John Brignell
describes the amount of motion needed to cause a slip error at a
distance of 500 meters: "Very roughly, without doing any
calculations, we are talking about the camera moving about the
thickness of a human hair."
The hosts of the BBC program were able to clock a stationary car
at 6 MPH. In tests of a moving vehicle, the laser gun produced
erroneous readings almost a third of the time, displaying speeds
that were off by as much as 26 MPH.
The devices can be upgraded and used as mobile speed cameras,
particularly in the UK where an estimated five million drivers
have been convicted based on laser speed readings over the past
five years.
"I am 100 percent certain that these devices are not suitable for
gathering legal evidence of vehicle speeds," said Paul Smith,
founder of the Safe Speed road safety campaign. "They make
mistakes and the BBC film proves it. Millions of drivers will be
entitled to refunds, licence points removed and in some cases a
large amount of compensation."
09-14-2005, 01:59 PM
#25
928 Collector
Rennlist Member
Rennlist Member
Originally Posted by Ron_H
BBC pointed out that there's no difference between the US and British versions.
Umm ... aren't the UK versions left-handed?
09-14-2005, 02:37 PM
#27
Chronic Tool Dropper
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Originally Posted by heinrich
Umm ... aren't the UK versions left-handed?
I think the correct term is "under handed", ands applies to both US and UK models.
In The Great and Socialist Republic of California, a laser operator, IIRC, needs some 8 hours of training for a radar unit, and an additional 4 for laser. Numbers may be off some, but the idea is that only operators trained on radar and with addirional laser training can use the equipment to gather evidence.
In the few radar tickets I've received, the court and I have a discussion about who is qualified to operate the unit. I compare my qualifications with the officers', and the court is obliged to go with my judgement. The legal issues around who can operate and calibrate a mobile radar unit are critical. Get the officer to admit that he did the 'required' calibration before and after your ticket, then go after his qualifications to do the calibration.
In each case, when it is time to close for the kill, the prosecution has decided to "abandon the prosecution in the interest of justice." In one case, when the prosection was offering plea-bargains outside the courtroom before trials, I made a point to say that I had enough info to cause the officer to not be able to write radar tickets, and to cause the city to refund all radar tickets he'd issued. My case was held to last (not a good thing for me), by which time the officer had managed to disappear from the court. Don't want to establish any 'dangerous' precedents, do we?
At my advanced age, I no longer tempt speeding fate regularly. As much as it is necessary to beat down radar tickets given unjustly, the real probability is that folks are speeding and they are getting caught. Are the speed laws themselves faulty? Sure, for many drivers. Still, traffic laws are there to protect virtually everyone from vitrually everyone else. So they are written to the lowest denominator, the poorest driver in the most mechanically unsound car or truck. Sucks for the rest of us, but it is intended to punish that lowest denominator and protect us from them.
90% of all drivers consider themselves "above-average". It's a new "mean-plus" statistical model.
Or, in my best 'dirty harry' voice: "A man's got to recognize his limitations." I'm the slow guy at the back of the pack on fun-drives.
