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The Lowdown on Lidar

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Re: The Lowdown on Lidar

#51
post #46

Earlier quoted context omitted.

That argument works in some countries while in others it doesn't. In UK only people who are explicitly listed on the insurance document can drive the car, and the police can demand that you tell them who was driving the car at the time. In some other EU countries like Poland, you buy insurance for the car,not the driver,so literally anyone can drive it(with your permission of course). Then if you are caught by a spee…

> In UK only people who are explicitly listed on the insurance document can drive the car That's not entirely true, it depends on your insurance. It's an offence to drive a car without insurance, and an offence to allow someone who is uninsured to drive your car. Some insurance policies do not extend the insurance you took out to driving other peoples cars. However, some fully comprehensive policies do have third par…

Ok, I didn't know that. Still, it works another way around than it does in countries like Poland - you have to have your own insurance,to drive somebody else's car. While in Poland you only buy insurance for the car,and anyone with a valid drivers licence is automatically covered by the insurance purchased for that car(unless they are doing it without the permission of the owner, in which case the insurance is invalid).

Re: The Lowdown on Lidar

#52
post #22

Earlier quoted context omitted.

Possibly because the cost/benefit just isn't there. In the UK, the data shows that speeding (excessive speed for the conditions above the speed limit) is the primary cause in single digit percentage of accidents. I believe there's data from 1996 and 2007 for this, will dig it out when I'm not on mobile. If you want to spend money on accident prevention, there's much better things to target than speeding.

It's not about saving lives. It's about revenue generation.

Speed limit laws don't exist to generate revenue. They exist to disincentivize speeding.

If speed limit laws didn't exist, can you imagine lawmakers saying, "We need more money. Hey, I know! Let's charge people money for driving over a certain speed!"

Re: The Lowdown on Lidar

#53

Well, he fought with half science: he came up with a set of testable hypotheses, but didn't actually run any of the tests. I guess that's as scientific as cosmology :-)

I think all he way trying to say that there are ways that a LIDAR gun could give a false reading, and there's no current incentive for law enforcement/manufacturers to ensure accuracy. In fact there's an incentive for both the manufacturer to emphasise accuracy based on successful prosecutions, and for police to emphasise accuracy to prevent large-scale contesting of tickets. They are used for law-enforcement, but pr…

Where are you people getting your information that they aren't available for public scrutiny? Has no one ever heard of Guys of LIDAR? http://www.guysoflidar.com/

Granted, they can't dump the firmware these devices use but they are very telling in what these detectors can pick up, can't, real world examples, and so on.

Re: The Lowdown on Lidar

#54
I've wondered sometimes if it would be possible to fight erroneous speeding tickets using the repeated GPS pings your phone or nav unit makes while using them for directions.

Re: The Lowdown on Lidar

#55

I hope this information, or the equivalent, filters into the awareness of judges. I was in traffic court in Virginia last year and, as I was waiting for my case, heard the judge explain to several defendants who were there to challenge their lidar tickets that the lidar was essentially infallible and could not be confused by other cars on the road. And this was an intelligent judge who seemed unusually sympathetic to…

Unfortunately judges are people and if you have tons of people coming in with just "LIDAR is not accurate enough to prove reasonable doubt" compared to cops bringing in studies proving their accuracy it is difficult to listen to it.

Re: The Lowdown on Lidar

#56

Earlier quoted context omitted.

The fundamental reason is because drivers feel entitled to speed and most voters are drivers. People with expensive cars further believe they've paid for the privilege of violating more laws more often, and those people are also more influential in policy setting. There are lots of expressions of this fundamental reason, such as people throwing a fit about automated license plate reading in the name of privacy. But o…

OR it could be because speeding isn't that dangerous and the current limits on most roads don't represent what speed people actually drive at or what speed people could safely drive at. It's different on residential streets, but on freeways I think the way Germany handles it is better. Speeding tickets (and most traffic violations really) are not about safety or curbing behavior they're about generating revenue for t…

Speeding is extremely dangerous. It's ludicrous to argue otherwise. A third of crashes (including fatal crashes) involve speeding, and the faster you are driving the more likely you are to die or fatally injure another.

Also, changing the speed limits on roads have been studied and it doesn't make a humongous difference. The government usually sets the speed limit at slightly lower than the average speed people actually drive.

Re: The Lowdown on Lidar

#57
post #27

Speed radars are good for speed traps, but not so great to prevent speed related incidents. They share the same fatal flaw with all other single-point speed meters: You can just slow down for a minute, while you pass by the speed trap, and then speed up for the rest of your trip. Instead, a 2-point speed meter (i.e. license plate readers every few miles, measuring time between matching reads) system is superior becau…

"I can't believe [average speed camera systems are] not implanted at least in all interstate freeways." Possibly because a civil society, favoring the preservation of a measure of basic autonomy, does not implement every measure for tracking, enforcing, circumscribing, and monitoring the people.

In practice, they're actually very good for improving traffic flow on busy roads - because almost everyone is driving at the same speed, jams just don't form in the same way. The utilitarian argument for them is very strong.

Re: The Lowdown on Lidar

#58
post #22

Earlier quoted context omitted.

Possibly because the cost/benefit just isn't there. In the UK, the data shows that speeding (excessive speed for the conditions above the speed limit) is the primary cause in single digit percentage of accidents. I believe there's data from 1996 and 2007 for this, will dig it out when I'm not on mobile. If you want to spend money on accident prevention, there's much better things to target than speeding.

It's not about saving lives. It's about revenue generation.

Don't be ridiculous, If it was about revenue there would just be more toll booths.

Re: The Lowdown on Lidar

#59

Earlier quoted context omitted.

The fundamental reason is because drivers feel entitled to speed and most voters are drivers. People with expensive cars further believe they've paid for the privilege of violating more laws more often, and those people are also more influential in policy setting. There are lots of expressions of this fundamental reason, such as people throwing a fit about automated license plate reading in the name of privacy. But o…

OR it could be because speeding isn't that dangerous and the current limits on most roads don't represent what speed people actually drive at or what speed people could safely drive at. It's different on residential streets, but on freeways I think the way Germany handles it is better. Speeding tickets (and most traffic violations really) are not about safety or curbing behavior they're about generating revenue for t…

A Dutch engineer once told me (back before 2004 I guess ) that they once raised the speed limit on the roads in Netherlands only to find average speed decreased.

His explanation IIRC was that 1. once people broke the limit it didnt matter how much and 2. when speed limits felt more correct more people respected them.

I'd love to know if anyone has any pointers to research on this as around here speed limits are weird. (80 in places where you obviously can't even drive 80 and 80 on the highway, -four lanes)

Re: The Lowdown on Lidar

#60
post #22

Speed radars are good for speed traps, but not so great to prevent speed related incidents. They share the same fatal flaw with all other single-point speed meters: You can just slow down for a minute, while you pass by the speed trap, and then speed up for the rest of your trip. Instead, a 2-point speed meter (i.e. license plate readers every few miles, measuring time between matching reads) system is superior becau…

Possibly because the cost/benefit just isn't there. In the UK, the data shows that speeding (excessive speed for the conditions above the speed limit) is the primary cause in single digit percentage of accidents. I believe there's data from 1996 and 2007 for this, will dig it out when I'm not on mobile. If you want to spend money on accident prevention, there's much better things to target than speeding.

%of total accidents is amost meaningless. % of accident deaths or even %of totaled cars would be a much better indicator. A parking lot fender bender is vary different than an 80MPH head on collision.

Also, even if speeding is not the direct cause of an accident it increases the damage resulting from an accident.

PS: It has been estimated that hard limiting private vehicles to 40MPH would have saved over 2 Million lives in the US. Not that I am promoting such a low speed limit but people really don't understand the dangers of speed. Every year after 1945 at least 30,000 people died with a peak well over 50,000.

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