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The Lowdown on Lidar

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Re: The Lowdown on Lidar

#211

Post by Shivetya »

michaelt wrote: post #170
timthorn wrote: post #57

Earlier quoted context omitted.

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.

The utilitarian argument for them is very strong. Doubtless a national numberplate recognition system would be effective at enforcing the speed limit. Once we have it, it would also be of great utility to investigate kidnappings and terrorism. And serious and violent crime. And vehicle thefts. And drug trafficking. And driving without a license, insurance, or tax. And lying about your address to get your kid into a g…

We already have numberplate recognition and its essentially on a national scale, just not completely linked up from jurisdiction to jurisdiction. License plate scanners are becoming rampant in some areas, they apparently have never been successfully blocked, all for reasons you listed and also as "license plates and vehicles don't have rights". The favored method for abusing a person's rights is to target their things

Re: The Lowdown on Lidar

#212

Post by driverdan »

mrfusion wrote: post #114

When I was a teenager I tried to fight a speeding ticket, and prepared a presentation like this with several good points (I think). Come court day, I got all dressed up, stood up when called and started my arguments ... and the judge simply cut me off after two sentences and said "guilty". I'm surprised this guy was allowed to present his whole argument and it actually convinced a judge.

Did you appeal? You can always appeal your first court hearing. The key is to talk to the prosecutor beforehand. They will almost always plea it down.

Re: The Lowdown on Lidar

#213

Post by NDizzle »

squeaky-clean wrote: post #132
kudu wrote: post #83

Why do HN mods keep changing the title from meaningful ones, which make the reader interested in the content, to generic, vague ones? You'll see that there's definitely a correlation between the moment that HN mods change the title and the post dropping off the top frontpage spot.

I saw the earlier title of this post while flipping through HN on my phone, and I wanted to read the full article during my lunch break. Now here I am, I checked the front page and was very confused where the post I was interested in went, and why some post apparently describing Lidar is at the top. I guess they're trying to keep the title to match the title of the link/article. But sometimes the article just has a b…

I too have the same experience.

It's not possible to mentally queue up items to read throughout the day. All the titles will have changed by that point.

Re: The Lowdown on Lidar

#214

Post by eric_h »

diminoten wrote: post #146
eric_h wrote: post #137

Earlier quoted context omitted.

The original title is, indeed, misleading. The article is not about LIDAR specifically, but about how LIDAR is (mis)used in speed enforcement. IMO, the title change was warranted.

I think at this point your beef is with PG himself, or whoever he had write those guidelines. The thing the mods are trying to avoid is link baiting, and they tend to err on the side of "no exceptions". I prefer this, as any other option may lead to more unintentional bias, or worse.

I suppose that "Josh Bloch Fights a LIDAR Speeding Ticket (with Science)" is a bit more link bait-y than "The Lowdown on LIDAR". I would also argue that the former compactly explains the entire content of the article, much more so than the latter, especially given that the author claims no expertise on LIDAR.

Regardless, I still would have preferred the original title. Perhaps removing the reference to Josh Bloch (and, perhaps, the parenthetical "with science") could have been dropped to reduce its link baity-ness.

As an addendum, I clicked on the link and read the article after the title had been changed to match the article's title, so perhaps my stated preference, as an afterthought, is completely unfounded.

¯\_(ツ)_/¯

Re: The Lowdown on Lidar

#215

Post by slyall »

adamtj wrote: post #205
kudu wrote: post #83

Why do HN mods keep changing the title from meaningful ones, which make the reader interested in the content, to generic, vague ones? You'll see that there's definitely a correlation between the moment that HN mods change the title and the post dropping off the top frontpage spot.

I would assume such changes come from a desire to be accurate. But accurate how? In what way? That depends on the purpose of the title. As I see it, our differences of opinion on this topic stem largely from misunderstanding it. I think it's not at all clear what we're even talking about, so we wind up arguing about slightly different things and fail to come to a consensus. I think that we need to really understand t…

I saw the title and google link and thought it would be someone from Google talking about the LIDAR system they use in their self-driving cars. I'd actually just read an article that said they cost $70,000 each so I was thinking "Maybe they have a way to drastically reduce the price or are going to say why they can't".

Re: The Lowdown on Lidar

#216

Post by bicubic »

dzhiurgis wrote: post #188

Perhaps anyone can explain me why Lidar is not dangerous to sight? Whenever you see anyone working with lasers they'd wear protective glasses. Now I realise Lidar uses infrared wavelength which is not visible to us, but that does not mean it's not dangerous, or does it?

Non-visible lasers pose a much bigger hazard than visible. Intense visible light triggers an involuntary defence called the blink reflex whereby we blink before the retina absorbs enough energy to get damaged. Lasers outside the visible range don't trigger the blink reflex and can destroy the retina before you know what happened.

Lidar operates at relatively low power and relies on very sensitive detection in a very narrow wavelength range to identify reflections.

Re: The Lowdown on Lidar

#218

Post by mnarayan01 »

Karunamon wrote: post #163
mnarayan01 wrote: post #130

Earlier quoted context omitted.

> Further, what happens when you commit a crime where there are no witnesses? Someone testifies as to what they've witnessed that makes them believe you are guilty, giving you a chance to question them about any flaws.

Okay. And how does a speed/red light camera preclude this?

IANAL but I don't believe it does. In a criminal trial introducing one as evidence would require some substantial effort (witnesses testifying to location, lack of tampering, etc), but I believe (again, IANAL) that generally states treat camera violations as civil, thus avoiding this work. Whether that's a good thing or not is a different question.

Re: The Lowdown on Lidar

#219

Post by puredemo »

shangxiao wrote: post #131
Karunamon wrote: post #93

Earlier quoted context omitted.

Agreed - the original title, about a guy beating a LIDAR ticket, was much more descriptive than this headline, which effectively says "This article is about LIDAR".

It was the fact that the guy was Joshua Bloch which got me to read the presentation - and I'm totally glad I did! I would never have read it if it was just named "The Lowdown on Lidar"

So appeals to authority work really well on you..

Re: The Lowdown on Lidar

#220

Post by Scoundreller »

mortov wrote: post #69
Liesmith wrote: post #58

Earlier quoted context omitted.

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

That would only be the case where people accept tolls & toll booths on roads as an acceptable thing. Sure, they're common in Canada and the US but in some other countries they lead to years of civil disobedience, protests and eventual scrapping by newly elected governments : http://en.wikipedia.org/wiki/Skye_Bridge#Toll_controversy Speed fines have the semi-respectibility claim of trying to reduce accidents/dangers o…

I'm waiting for someone to calculate the greenhouse gas emissions created by toll booths.
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