The Lowdown on Lidar • Hacker News Board

Re: The Lowdown on Lidar

#31

Post by simias » Thu, Jul 31, 2014, 4:01 PM UTC

thrownaway2424 wrote: post #16

ihaveajob wrote: post #12

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…

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…

I'm not sure speed traps are preferred by voters over a 2 point system. I can say that as a driver I'd much prefer the 2 point system instead of the vast quantity of speed trap radars we have in france right now.

I think the main difference is the price, especially since 2 point systems turn into n-point systems if you have a lot of intersections.

Re: The Lowdown on Lidar

#32

Post by simias » Thu, Jul 31, 2014, 4:01 PM UTC

thrownaway2424 wrote: post #16

ihaveajob wrote: post #12

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…

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…

I'm not sure speed traps are preferred by voters over a 2 point system. I can say that as a driver I'd much prefer the 2 point system instead of the vast quantity of speed trap radars we have in france right now.

I think the main difference is the price, especially since 2 point systems turn into n-point systems if you have a lot of intersections.

Re: The Lowdown on Lidar

#33

Post by awjr » Thu, Jul 31, 2014, 4:01 PM UTC

The reading was taken at a distance of 1300 feet with a handheld device that is not meant to be used handheld beyond 1000 feet. That's a significant distance. I'm assuming the cop was hiding or trying to stay hidden.

Re: The Lowdown on Lidar

#34

Post by toomuchtodo » Thu, Jul 31, 2014, 4:02 PM UTC

Gracana wrote: post #18

toomuchtodo wrote: post #10

Earlier quoted context omitted.

One word: Discretion "Confronting Automated Law Enforcement" http://robots.law.miami.edu/wp-content/uploads/2012/01/Shay-...

That's a pretty short summary of a 44 page document. Can you elaborate a little more?

Sure. Do you want to live in a world where every time you violate the letter of the law you're penalized? Before you answer, consider that you're going to have to keep 100-200 years of law hot in memory to ensure your daily compliance.

Re: The Lowdown on Lidar

#35

Post by gambiting » Thu, Jul 31, 2014, 4:03 PM UTC

stronglikedan wrote: post #25

ihaveajob wrote: post #12

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…

Perhaps it's because you're ticketing the vehicle's registered owner, but not necessarily the driver.

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 speed camera and your face isn't visible you can say that someone else was driving and you don't remember who - in theory there is a penalty for not saying who(200zł = ~$60), but most people opt to pay it instead of the speeding ticket which can be higher - or go to court and dispute that they cannot pay for the crime they didn't commit and they cannot be forced to remember something which they don't remember - and they sometimes win.

Re: The Lowdown on Lidar

#36

Post by grecy » Thu, Jul 31, 2014, 4:10 PM UTC

ihaveajob wrote: post #12

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 detector is] not implanted at least in all interstate freeways.

They are very common in Australia. It takes a photo of your license plate, then another 10km (or whatever) down the freeway. If the two photos are less than x seconds apart, you get a speeding ticket.

Re: The Lowdown on Lidar

#37

Post by Zelphyr » Thu, Jul 31, 2014, 4:11 PM UTC

ihaveajob wrote: post #12

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…

Unfortunately, because police departments are often (mostly?) funded by things like tickets[1], they actually have an incentive to care less about traffic safety in this case. If the goal was truly to get people to stop speeding the municipalities could increase fines to a level that actually serves as a deterrent.

1: I only have second-hand/anecdotal knowledge that these departments are funded by fines. Still, I believe my point remains.

Re: The Lowdown on Lidar

#38

Post by Zelphyr » Thu, Jul 31, 2014, 4:13 PM UTC

taeric wrote: post #4

I confess I was expecting to not care for this. I'm not sure how any of it should be surprising, as it seemed fairly straight forward analysis of the tools. That said, this was a ridiculously fun read. More detailed than expected for some parts, and always informative. I'm glad it did not come across as anti speed detectors. Really more of a "know the limitations."

Me too. Though I would've been over the moon if he'd said he wore his "Back off man. I'm a scientist." shirt to court.

Re: The Lowdown on Lidar

#39

Post by Karunamon » Thu, Jul 31, 2014, 4:13 PM UTC

throwaway888888 wrote: post #30

thrownaway2424 wrote: post #16

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…

a person turns into a sociopathic scofflaw as soon as he gets behind the wheel Boo this man! That is an ideological position, and I could easily apply the same blanket label of absolute sociopathy to law enforcement, and I'd be just as wrong. But there's a difference between a mechanized, automatic law enforcement system and a law enforcment system that is implemented as a practice performed by living human beings. T…

Sociopathic? Maybe not, but scofflaw? Most definitely. Drivers have a really hard time with really basic things. Speed limits, red lights, turn signals, proper lane etiquette, and other common courtesies.

Every single one of those things has a law attached. People either forget or think that the law doesn't apply to them.

Re: The Lowdown on Lidar

#40

Post by Karunamon » Thu, Jul 31, 2014, 4:14 PM UTC

meritt wrote: post #14

justinsb wrote: post #9

Can anyone tell me why speeding tickets aren't enforced with video cameras (like red-light tickets are)? It would seem to be much more accurate, much easier to enforce, and much harder to dispute. Irrespective of the rights or wrongs of speed limit laws, I do believe that consistent and efficient enforcement can only be a good thing.

Because video cameras are arguably illegal. You can't face your accuser in court, therefore it should be thrown out. Got a speeding ticket from one of these lovely cameras in the state of Iowa, then I was sent a bill from some company in Phoenix with bold threats that if I didn't pay the fine, it'd be submitted to a collection agency and negatively impact my credit score (because otherwise I'd just have not paid it.…

This is a common myth.

The camera is not your accuser; the state is, using the camera as evidence of your violation.

It would be no different than a security camera catching you breaking into a building. The camera doesn't sue, the owner of the building does.