The innovative power of the hangover
Students invent quieter leaf blower
231–240 of 440 posts
Re: Students invent quieter leaf blower
#232I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower). What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. It sounds like a dental drill amplified through a set of loudspeakers. I would kill to get a commercially de…
"instead they blew it"
I see you!
Re: Students invent quieter leaf blower
#233Can someone explain to me what "quieter" means in this context and/or how it's calculated? I don't understand what they mean when they say reducing the noise by 2 decibels made it 37% quieter -- it wasn't making only 5 decibels of noise before, was it? >>Their design cuts the most shrill and annoying frequencies by about 12 decibels, which all but removes them, making them 94% quieter. The team reduced the overall le…
Decibels are logarithmic; a 1 dB reduction in sound is ~26%.
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.
Re: Students invent quieter leaf blower
#234Can this idea be adapted to vacuum cleaner? Would appreciate that since my head starts to spin when I hear one.
It's called hearing protection. People wear it while operating heavy machinery, shooting guns, or being at rock concerts. Might not hurt to keep a pair around your home.
Re: Students invent quieter leaf blower
#235Earlier quoted context omitted.
Elon Musk at one point once suggested Tesla would make a quiet leaf blower - due specifically to the noise. I wonder if Tesla perhaps has a whole bunch of technologies they're developing incognito in the background - or if he's perhaps being limited for some artificial reasons? It may just be a market size issue - and cities passing bylaws to disallow gas powered, only allow electric under a certain dBs is the fix; a…
Is that really what people want? Leaf blowers to me are possibly the least interesting, least appealing way to use modern tech To clarify, as a research project, cool. We can probably use any new developments elsewhere. But as a tesla product, just why?
They know and have the supply chain setup, and they are arguably specialists in electric motors?
Well, and technically specialists in rocket motors too - at least access via SpaceX engineers.
Re: Students invent quieter leaf blower
#236Earlier quoted context omitted.
A canopy of unblown leaves can cause damage to the surfaces underneath through mold or mildew. In some cases, this damage can be effectively permanent if let go long enough.
>In some cases, this damage can be effectively permanent if let go long enough. I have no expertise in leaf or ground quality. If this is the correct, even in very rare cases, over the quarter-billion years or so that trees have been shedding leaves, should the entire planet not be barren wasteland by now? What's the process by which leaf damage is undone over very long time periods?
I'm talking about man-made structures that are prone to retain moisture like sidewalks or decks.
Re: Students invent quieter leaf blower
#237I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower). What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. It sounds like a dental drill amplified through a set of loudspeakers. I would kill to get a commercially de…
> What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe.
They didn't change anything about the blower. They made an adapter you plug on the front that tries to cancel out the the worst offending frequencies. Like a silencer, but for leaf blowers. It's the red thing you see on the pictures.
Re: Students invent quieter leaf blower
#238You kind of get the impression that manufacturers never even bothered to try to make them quiet before.
While I'm usually very free market, I think this is a case where we have such a high negative externality that we need regulation. Everyone is annoyed by leaf blowers, but the tradeoff for users, especially commercial, of paying the extra cost isn't worth it to them. I don't think we should ban them, but have a maximum permitted noise level.
Re: Students invent quieter leaf blower
#239"Their design cuts the most shrill and annoying frequencies by about 12 decibels, which all but removes them, making them 94% quieter. The team reduced the overall leaf blower noise by about two decibels, making the machine sound 37% quieter." [1] Somewhat upsetting here... I don't have a problem with people doing things like this and students need encouragement, but we are talking about shifting from the sound of a…
> JHU should make these comments!, and also offer their designs for free given these are public orgs using mostly public dollars JHU is private. It seems like this research may have been sponsored by Black & Decker, also private.
"Johns Hopkins researchers' success in winning federal funding—which accounted for close to 87% of its 2022 R&D expenditure—enables them to pursue projects in an array of fields, from human genetics to artificial intelligence."
[1] https://hub.jhu.edu/2024/01/05/nsf-higher-education-research...
Oh yes... "private" org using public dollars is more appropriate.
Re: Students invent quieter leaf blower
#240Moxie Marlinspike tried this. Pretty decent try.
https://twitter.com/moxie/status/1582154037700399104?lang=en