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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#361

Post by SV_BubbleTime »

SOLAR_FIELDS wrote: post #322
SV_BubbleTime wrote: post #228

Earlier quoted context omitted.

Because it’s 2db overall. No camera is going to pick that up because no human is going to hear it. They claim 37% reduction, but that isn’t true for human perceived volume.

And as has already been pointed out elsewhere, even if it was an actual 37% reduction it would be useless anyway since no commercial operation would be viable with electric leaf blowers. They’re good for blowing the leaves out of a homeowners driveway and not much else

Honestly, my EGO “670cfm” on turbo is really quite good. But yes, I use it for maple leaves.

Re: Students invent quieter leaf blower

#362

Post by barfbagginus »

mlrtime wrote: post #72
klankschap wrote: post #57

How about leaving leaves for what they are. Just leave them and move on with your own life.

Have you ever considered it's just a name and it's actually used on more than just leaves? Or was the post sarcasm? Poe's law.

If they are serious, then they are making the equivocation fallacy - arguing by using a word in two different ways and hoping nobody notices the mistake.

But it's likely they are doing this as a pun, where readers are supposed to notice the equivocation, and find it funny or annoying. For example we can imagine a lazy husband saying "they're called leaves, so that is why I'm going to leave them for tomorrow!" This is not a serious attempt to equivocate the two meanings of "leave" - it communicates non willingness while also causing laughter or annoyance.

An obvious equivocation is not usually an effective argument. But making it a pun can win points with a good humored audience, because they find it funny. Funny arguments can influence opinions even though we know they are nonsense.

TLDR; when people mix word meanings secretly to confuse people and win points, it's equivocation, and that's a morally bad argument and is usually unacceptable. But when people mix meanings blatantly to win points by being funny, it's a pun, and that may be acceptable in non-serious conversations.

Re: Students invent quieter leaf blower

#363

Post by kylebenzle »

kjkjadksj wrote: post #336
SOLAR_FIELDS wrote: post #308

Earlier quoted context omitted.

And the other underlying problem implied there is that electric leaf blowers are only viable for household use. They are just so completely impractical for commercial use that no one will ever use them.

They are also nearly as loud to my ear as a gas one. Turns out blowing air is noisy.

I guess I'm glad we don't use your ear as a way to measure sound levels then because we would all be way off.

Gas-powered leaf blowers typically operate around 90-100 decibels (dB), while electric leaf blowers usually range from 60-70 dB.

Re: Students invent quieter leaf blower

#364

Post by ericmcer »

kjkjadksj wrote: post #300
modeless wrote: post #296

We don't need quieter electric leaf blowers. We need to ban the gas ones, with no grandfather clause. Not just for the noise pollution but the local air pollution. It's crazy the volume of air that can be ruined by a single gas leaf blower, far worse than modern cars, and they are inescapable in cities.

They’ve been banned for years in some cities. The issue is there is zero enforcement.

I am so tired of noise and air pollution having 0 enforcement in cities, but if a car is parked for 15m too long in a metered spot they are ready like hawks to swoop down and dispense a $60 ticket.

I was eating lunch at a restaurant few weeks ago and a parking enforcer was ticketing a car right next to us. A few feet past the car three dudes on motorcycles were revving their engines and blasting music at the stop light. No one could talk and the air smelled for a couple minutes after they left. It just seemed so wrong who was getting punished and what cities prioritize in that instance.

Re: Students invent quieter leaf blower

#366

Post by KingOfCoders »

fkyoureadthedoc wrote: post #359
KingOfCoders wrote: post #185

Earlier quoted context omitted.

"In this case 0 were read in order to rush and make a low effort joke" You should work for the NSA or the three later agency of your country, you can spot what people do possibly thousands of kilometers away! There was this one Columbo episode, one of my favorites, where the NSA wanted to hire such a guy. Sadly it was all fake. So the cynical side of me assumes you also can't spot what I'm doing at my computer, and y…

The point stands that you lied about the number of comments to aid your position, and that you didn't read even the above the fold comments. So you weren't making a low effort comment, you were trying to start substantive discussion, but you didn't even read other comments? Sounds likely. I guess since we're telling pointless stories about TV shows I should comment on your bright future as a HumancentiPad component.

I was not making a joke. But that's not fitting the narrative in your head.

You invent other people in your head, me "rushing to the comments to make a low effort joke", ignoring what they say ("I was not making a joke"), then make up what they say, so you can attack them, instead of an argument ("I was not making a joke").

"The point stands that you lied about the number of comments"

I never said how many comments I have read. How can I lie about the number of comments I have read then? Are you mixing up comments? You see me highly confused.

[Edit] I made the comment because there are many leaf blowers here - and while they do individually safe time to the user, they create hell for everyone else who might be noise sensitive. And I made the comment to express that there is already an invention, the rake. So people could use that instead of optimizing their comfort and time against everyone else wellbeing. But people don't care.

Re: Students invent quieter leaf blower

#367

Post by digging »

cchance wrote: post #340
digging wrote: post #318

Earlier quoted context omitted.

Hm, residential walking surfaces are easily swept with a broom though.

He's saying to leave it on the yard to break down, if you do that it turns to slippery ass mud eventually, and guess what people like to be able to walk in their lawns, if we're sweeping up the entire yard so that we can use our yard without it being slippery and muddy from decomposed leaves... congrats you've just fucking reinvented the rake and leaf blower

> you end up shoveling a layer of mud off your waking surfaces

Doesn't imply that the entire yard was being considered a walking surface

Re: Students invent quieter leaf blower

#368

Post by calfuris »

WaltPurvis wrote: post #346
SV_BubbleTime wrote: post #233

Earlier quoted context omitted.

But that is NOT the same as human perceived volume. Less 37% energy is not 37% less volume to humans. You won’t be able to tell the difference in volume except for the tone which could be more or less pleasing depending on the frequency they say they got 12db on.

I learned something new today (I didn't know decibels were logarithmic), but I still don't understand how it relates to "human perceived volume" as you put it. If a typical electric leaf blower makes 70 decibels of sound, it seems odd that cutting that to 67 decibels makes it sound 37% less loud. Perhaps it does, but I think I'll have to hear it to believe it. I may have to buy a sound meter and run some experiments.

The sound has 37% less power, but human perception of sound intensity is roughly logarithmic. Looking at the difference in dB will give you a better estimate of the perceived change than the difference in actual sound power.

Re: Students invent quieter leaf blower

#369

Post by modeless »

xkqd wrote: post #354
adrianmonk wrote: post #331

Earlier quoted context omitted.

That is exactly the kind of situation where regulations are needed. Sometimes the market can take care of things, and regulation isn't needed. But these workers don't have lots of leverage. If conditions are bad, they can't tell the boss "I have other options" and quit. So the market won't solve this case.

In all fairness, we’re not wrangling in a megacorp or small company / bad actor type. These are usually tiny businesses where the owner is busting their ass in the hot sun alongside their crew. These are usually the smallest of small biz, and oftentimes just a young guy and a single helper. I don’t believe we can expect lawncare prices to 4x, but this is a perfect example of targeting those who we should be supportin…

I am sympathetic to this argument. I also think the buyback program suggested upthread is probably a good idea.

Re: Students invent quieter leaf blower

#370

Post by pradn »

geocrasher wrote: post #248

What I loved about this is that all of their prototypes were with a stock leaf blower with *3D Printed* attachments. This really shows the value of the rapid prototyping that 3D Printing has allowed. It also shows that any of us could have done this with enough time and effort. And I don't mean literally any person- but there are a LOT of YouTube engineering channels that could likely have tackled this, had they been…

There's a lot of value in coming up with a clear problem statement and giving it to the right people. We see this with DARPA, at a much bigger scale.
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