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Implausible and overfunded CPAP machine on Indiegogo

61 点作者 alkimie2将近 10 年前
My son (a physics student) wrote to me to point me to a crowdsource project for a CPAP machine.<p>https:&#x2F;&#x2F;www.indiegogo.com&#x2F;projects&#x2F;airing-the-first-hoseless-maskless-micro-cpap#&#x2F;story<p>My immediate thought upon seeing the mock up was: balony, with a capital &#x27;B&#x27;.<p>It is a tiny thing looking a little like a plastic moustache. I do not see how such a small package could store enough power to run a CPAP device. It is a simple question of moving mass. People breath about 5 liters of air per minute at a low activity level. That’s 2400 liters in an-8 hour period. Air weighs about 1.2 gm&#x2F;l = 2.88 KG moved in an an 8 hour period. And that illustration did not seem to have much space for a battery. Not to mention space for the magical flapping air pumps derived from CPU coolers!<p>And they claim a price of $3 per device… And it’s disposable.<p>They also say they are using a zinc air battery, which has energy density of 470 Wh&#x2F;kg or .47 Wh&#x2F;gm. Let’s generously say that they have 10 gm of battery—that’s 5 watt hours. Lets even more generously say that they have 8 watt hours. That’s 1 watt continuously for a night of sleep.<p>They are saying they can operate a CPAP machine on 1 watt, have it be the sized of a junor tootsie bar, and sell it for $3 per device.<p>The question I’m asking here is what should we do as engineers? Ethically, I mean. I really hate to see people taken in by such an obvious scam.

25 条评论

amluto将近 10 年前
Let&#x27;s try the math for real.<p>The site claims that the device can provide 20 cm H₂O (which is ~1961 Pa). Apparently some hypothetical normal man breathes at a rate of 6 liters (i.e. 0.006 cubic meters) per minute at rest [1]. If you pump a volume V of fluid across a pressure difference of ΔP, you&#x27;ve done work V·ΔP, which is 11.76 Joules per minute or 0.1961 Watts. Keep in mind that this is the work done, not the power consumed, but let&#x27;s be generous and assume a 100% efficient blower. We&#x27;ll also assume that no power is harvested during exhalation.<p>In eight hours, that&#x27;s 1.56 Watt hours.<p>Duracell&#x27;s zinc-air chemistry claims up to 442 Watt hours &#x2F; kg [2]. That&#x27;s about 3.5 grams of zinc-air goo per night, ignoring packaging, blower loss, etc.<p>This seems entirely plausible to me.<p>[1] <a href="http:&#x2F;&#x2F;www.normalbreathing.com" rel="nofollow">http:&#x2F;&#x2F;www.normalbreathing.com</a><p>[2] <a href="http:&#x2F;&#x2F;media.ww2.duracell.com&#x2F;media&#x2F;en-US&#x2F;pdf&#x2F;gtcl&#x2F;Technical_Bulletins&#x2F;Zinc%20Air%20Tech%20Bulletin.pdf" rel="nofollow">http:&#x2F;&#x2F;media.ww2.duracell.com&#x2F;media&#x2F;en-US&#x2F;pdf&#x2F;gtcl&#x2F;Technical...</a><p>Edit: In the interest of precision, I should add that the analysis is accurate for an incompressible flow. Air is definitely compressible, so, if you pump air, more volume is going into the pump than is coming out, and you&#x27;re heating up the air (adiabatically if your pump is any good). So, with a compressible fluid, you have to consider not on the work done moving the fluid across a pressure difference but also the energy you&#x27;ve stored in the fluid by pressurizing it. The pressure difference for CAP is tiny here, though, so this would be a miniscule correction to the math above.
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amykhar将近 10 年前
I work in the sleep industry, and noted that the company making this device did not attend Sleep 2015 in Seattle. The fact that they were not present at the largest gathering of sleep professionals in the country this year made me really doubt their credibility.
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jerf将近 10 年前
&quot;People breath about 5 liters of air per minute at a low activity level. That’s 2400 liters in an-8 hour period. Air weighs about 1.2 gm&#x2F;l = 2.88 KG moved in an an 8 hour period.&quot;<p>I&#x27;m not sure if this device is plausible, but I know this calculation is not useful. You&#x27;re calculating the mass of air moved, which, first of all, does not itself say much about the energy required to do so; for instance, horizontal motion doesn&#x27;t require any net energy (though any real device doing so will of course need to do something to accelerate and decelerate, there&#x27;s nothing to say it can&#x27;t be very, very cheap). Second you appear to be discussing it as if there isn&#x27;t a pair of lungs right there providing motive power. I do that much moving of the air every day (plus a bit, probably, I&#x27;m a tall guy) with no batteries at all.<p>This thing is not responsible for &quot;moving all that air&quot;... it&#x27;s responsible for a <i>pressure increase</i> of the air, which is at least somewhat equivalent to saying it&#x27;s responsible for &quot;moving air&quot; but only a fraction of the value you computed. They say it is supposed to do from 1 to 20 &quot;centimeters of water&quot;. According to the Great and Mighty Internet, 20 cmH20 is 0.02 atmospheres, just to give some perspective. I do not have the math to calculate the energy requirement that represents when the air is in motion itself; my physics would only be sufficient to calculate the energy implied in pressurizing a closed container from 1 to 1.02 atmospheres, which is useless in this case. Perhaps someone else can pop up for that.<p>(Bear in mind I took a full standard College physics-for-non-majors course set, using full calculus, and what I know from that is that what I know is inadequate... if that also describes your experience, your education is inadequate too. We&#x27;re going to need to hear from someone with more specialized education.)<p>My suspicion is that yes, this device <i>is</i> plausible, but the final version is going to be larger than the versions shown. Whether it crosses over the invisible line where people become unwilling to wear it is anybody&#x27;s guess, but... sleep apnea <i>sucks</i> and those masks do suck too, so there&#x27;s some room for these guys to work in. I&#x27;d classify this as a &quot;considered risk&quot; rather than &quot;two orders of magnitude impossible&quot;. I reserve the right to change this assessment as more data comes in, especially a (good!) physics analysis of the real energy required to do this.
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smitec将近 10 年前
When you look at the math (as you have) it seems almost certain to be a scam. ResMed has a Technical note [0] on powering one of their devices form a battery, while product efficiencies can vary they are recommending ~30 Amp hour batteries for the 20 cmH20 this device is claiming to provide. It amazes me that indigogo doesn&#x27;t do something to stop this sort of thing when it gets to be such a well funded project (I&#x27;m sure other platforms are guilty of it too).<p>[0] <a href="http:&#x2F;&#x2F;www.rpc.com.au&#x2F;pdf&#x2F;battery-powering-products-usa.pdf" rel="nofollow">http:&#x2F;&#x2F;www.rpc.com.au&#x2F;pdf&#x2F;battery-powering-products-usa.pdf</a>
twistedpair将近 10 年前
<i>Is the Airing device FDA approved? No, not yet. However, we do believe the process of getting FDA clearance may be abbreviated.</i><p>Ha. I work at a company that makes medical devices. It&#x27;s just so damn easy, you know! Seems like a pretty blunt case of handwaving away this critical step. This is an electric device that controls if you can breath. This thing has a non-trivial risk of hurting someone through electrocution (it&#x27;s plugged into your conductive mucus) or asphyxiation (though hopefully you&#x27;ll wake).<p>So yeah, they&#x27;ll clearly just POST to the FDA certification API and get a response within a minute.
alvarop将近 10 年前
Everything seems to be worded just right in case they don&#x27;t deliver. From the FAQ: &quot;As a contributor to this Indiegogo crowdfunding campaign, you are supporting Airing’s intent to develop the world&#x27;s first micro-CPAP device.&quot;<p>Also, all physical perks have the disclaimer: &quot;Subject to FDA clearance and doctor’s prescription in the US and local regulation abroad.&quot;<p>From a financial perspective, I can&#x27;t imagine getting the device certified in multiple countries is going to be cheap. Would they also be expected to check doctors prescriptions in various languages somehow before delivering?
ChuckMcM将近 10 年前
<p><pre><code> &gt; what should we do as engineers? </code></pre> Well you can warn people off, but you can&#x27;t make people disbelieve what they want to believe. In similar situations I&#x27;ve suggested that folks wait until they can be ordered and the crowd funded units have shipped. Then they will have a good idea of what they are getting. If the crowd funding fails or they are poor quality, they will have saved themselves aggravation and money, if it works then they will be available as a product.
anonu将近 10 年前
If anything, this underscores the importance of this field. Sleep is an under-studied phenomenon. Sleep apnea is even more so... Consider the current field of options, none of which may be any better than the one proposed on Indiegogo. All you need to do is flip on some infomercials or flip through a SkyMall magazine to see that there are dozen of gizmos and gadgets that don&#x27;t work: chin straps, sprays, OTC mandibular advancement, etc.. etc.. The surgical options are not pleasant either. Look up &quot;UPPP&quot;.<p>One promising technology is a small pace-maker-like device that is implanted in the chest and stimulates the hypoglossal nerve while you sleep: <a href="http:&#x2F;&#x2F;www.medscape.com&#x2F;viewarticle&#x2F;834474" rel="nofollow">http:&#x2F;&#x2F;www.medscape.com&#x2F;viewarticle&#x2F;834474</a>
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chrisBob将近 10 年前
It looks like the found a good gullible market with lots of money, and it will be <i>years</i> before anyone complains. They have an earliest delivery date of 2017 depending on how things go with the FDA.<p>When I see something like that my first question is if the doctors involved are real or not.
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zamalek将近 10 年前
<i>I&#x27;m no engineer and my knowledge of CPAP extends to the amount of Googling I did since I saw this post.</i><p>Their constraints do seem very tight but I can conceive at least one way in that you could shrink the device down. There would be multiple actions in such a device:<p>1. During the inhale increase pressure. As noted by the image[1] this is achieved in the device with &quot;blowers.&quot;<p>2. During the exhale present a restriction to airflow, but don&#x27;t cut it off entirely. You could use something similar to an aperture to restrict airflow here.<p>3. Between the exhale and inhale maintain pressure. If you use an aperture-like-device you can simply close the aperture completely.<p>This means that the device becomes <i>partially</i> passive, reducing power requirements. I&#x27;m no expert but let&#x27;s assume that you are only inhaling 50% of the time - this cuts down the amount of time the &quot;blowers&quot; need to run by 50% (or can double their power consumption or something in-between). My uneducated opinion is therefore: remotely plausible.<p><a href="http:&#x2F;&#x2F;res.cloudinary.com&#x2F;indiegogo-media-prod-cld&#x2F;image&#x2F;upload&#x2F;c_limit,w_620&#x2F;v1434341774&#x2F;oszvr8ppyhnqsmj56jip.png" rel="nofollow">http:&#x2F;&#x2F;res.cloudinary.com&#x2F;indiegogo-media-prod-cld&#x2F;image&#x2F;upl...</a>
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Smushman将近 10 年前
Background on Airing, LLC, located in Burlington, MA.<p>I looked up Stephen A. Marsh (see <a href="http:&#x2F;&#x2F;www.fundairing.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.fundairing.com&#x2F;</a> under &#x27;inventor&#x27;).<p>Interesting guy - a strange history. He also is CEO of Encite LLC (also located in Burlington, MA). He does have many patents in fuel cells, etc.<p>Previous to Encite LLC he was CEO of a now-defunct technology startup Integrated Fuel Cell Technologies, Inc. (IFCTI)<p>Encite LLC was formed from IFCTI, through some obtuse legal machinations.<p><a href="http:&#x2F;&#x2F;www.potteranderson.com&#x2F;delawarecase-185.html" rel="nofollow">http:&#x2F;&#x2F;www.potteranderson.com&#x2F;delawarecase-185.html</a><p>I am no expert in law, but it sounds like he basically ran IFCTI into the ground as CEO, then bought it and its resources back at a large discount via Encite LLC. The previous board members tried to sue him but lost due to some ambiguities in the laws.<p>Maybe someone else has more?<p>BTW having used a CPAP I know it is not possible to generate the volume and pressure (particularly the pressure) needed by something this size without a quantum leap in current technology.<p>I can&#x27;t devise a method to prove and explain my conclusion. Perhaps someone more versed in the area can.
userbinator将近 10 年前
<i>The question I’m asking here is what should we do as engineers?</i><p>Talk about it and spread the word to others that this is impossible to do.<p>There&#x27;s also some interesting discussion here, mostly to the tune of &quot;it won&#x27;t work&quot;:<p><a href="http:&#x2F;&#x2F;www.eevblog.com&#x2F;forum&#x2F;crowd-funded-projects&#x2F;the-airing&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.eevblog.com&#x2F;forum&#x2F;crowd-funded-projects&#x2F;the-airin...</a>
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brock_r将近 10 年前
You are forgetting that it is your <i>lungs</i> that must move the 2.88KG in an 8 hour period.<p>The machine just has to maintain a positive pressure during certain portions of the breathing cycle.<p>What I see here is a possibly overly-ambitious design, but no obvious scam.<p>BTW, here is a video of Airing&#x27;s Chairman: <a href="https:&#x2F;&#x2F;vimeo.com&#x2F;130685879" rel="nofollow">https:&#x2F;&#x2F;vimeo.com&#x2F;130685879</a>
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Mz将近 10 年前
I don&#x27;t think there is an ethical obligation to do anything. I hope people contributing can afford to lose whatever funds they are pledging. They will have to seek FDA approval. If they don&#x27;t get it, no one is going to be buying some overhyped piece of plastic that doesn&#x27;t actually work.<p>One of the challenges we have currently is that the medical field is over regulated and there are excessive barriers to entry. Perhaps you can make your peace with the fact that it isn&#x27;t your money and if people want to hope against hope for something better and pledge a few dollars, that is their choice. Then the developers might get their shot at developing something new. Maybe it won&#x27;t meet every criteria they listed. Maybe it somehow will. Maybe it will be a complete flop. (Shrug)<p>Innovation only happens when there is some leeway for some of it to fail. $100k is a drop in the bucket for medical research. Why do you feel such a strong need to not even let them try? I suggest you let it go.
OopsCriticality将近 10 年前
&gt; The question I’m asking here is what should we do as engineers? Ethically, I mean. I really hate to see people taken in by such an obvious scam.<p>Skepticism is certainly warranted based solely on the timeline presented and my experience in medical devices.<p>As to the rest, you&#x27;re operating on incomplete information. According to the NSPE, &quot;Engineers may express publicly technical opinions that are founded upon knowledge of the facts and competence in the subject matter.&quot; You say, &quot;what should <i>we</i> do as engineers&quot;, so I&#x27;ll make the implicit assumption that you&#x27;re an unlicensed &quot;software engineer&quot; like many on HN. If so, consider that you may be operating outside your area of expertise without complete knowledge of the device. I would make careful public statements: I, for example, wouldn&#x27;t say &quot;I performed a first-principles analysis and, as an engineer, I find the device claims are impossible.&quot;
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skilesare将近 10 年前
There is breathing going on here so is there any chance that the breathing out could help recharge the battery in a similar way that a hybrid car charges your battery when you brake?<p>I also don&#x27;t think it is &#x27;disposable&#x27;. I think it is recyclable and from what I&#x27;ve seen the $3 is dependent on recycling them.
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gooseyard将近 10 年前
I believe the Airing thing is expected to use these things:<p><a href="http:&#x2F;&#x2F;www.murata-ps.com&#x2F;emena&#x2F;2012-05-22.html" rel="nofollow">http:&#x2F;&#x2F;www.murata-ps.com&#x2F;emena&#x2F;2012-05-22.html</a><p>I was also skeptical of the Airing claim, although after reading about the Murata piezo blower things, they&#x27;re amazing, whether Airing is able to make a CPAP out of them or not.<p>Frankly, as an old, fat, CPAP using guy, I&#x27;d rather eat mouldy cheese than use a nasal pillow CPAP device. Plus, the Airing thing would have to be strapped to my face anyway; at my Rx pressure it&#x27;d blow out of my nose within an hour. The hose on my traditional BiPap turbine machine doesn&#x27;t bother me at all.<p>I&#x27;d be delighted to have a smaller BiPap machine made out of these Murata things, if it meant a less bulky power supply and a smaller base unit.
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rebootthesystem将近 10 年前
Buy the right to post comments by pledging the smallest amount possible? Contact indigogo with the concern? Write a blog post and get help having it widely linked? Alert the authorities?<p>On the other hand, it might br hard to convince a lot of people that this isn&#x27;t real. After all, most of humanity believes some version of supernatural nonsense which includes such things as people flying, resurrecting, partin seas, singing bushes, talking snakes, 6,000 year old earth, rapture, being chosen, paradise, etc. in other words, there&#x27;s plenty of empirical evidence to show science and reason don&#x27;t stand a chance. Yet.
semiazas将近 10 年前
Call Indiegogo to task. They&#x27;re developing a reputation for shady practices. Considering they get their cut whether the startup is real or not begs the question are they honestly diligent in vetting a project? Given their history it seems to me they&#x27;re more interested in their piece of the pie and believe those foolish enough to buy in get what they deserve. You won&#x27;t see them refunding their portion of a fund when it becomes apparent it was a scam. They carefully pretend nothing bad happened and go on down the road to the bank.
Rooster61将近 10 年前
I&#x27;m fairly skeptical myself, but if they do put their money where their mouth is, this will be a fantastic product. I use a cpap, and I can tell you flying international lugging a machine around is a regular pain in the ass.<p>That said, my dollars are staying snugly in my pocket for this campaign. It&#x27;s pretty farfetched, and I don&#x27;t like the metric they used to illustrate the actual pushing power. It doesn&#x27;t add up.
feld将近 10 年前
Maybe the doctors are being scammed as well? Gilmartin specializes in sleep medicine<p><a href="http:&#x2F;&#x2F;www.vitals.com&#x2F;doctors&#x2F;Dr_Geoffrey_Gilmartin&#x2F;profile" rel="nofollow">http:&#x2F;&#x2F;www.vitals.com&#x2F;doctors&#x2F;Dr_Geoffrey_Gilmartin&#x2F;profile</a>
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nugga将近 10 年前
You really don&#x27;t need to read the page further after seeing &#x27;flexible funding&#x27; with a target of 100k. Sadly indiegogo is a scamsta&#x27;s paradise for allowing flexible funding for non-charity drives.
mcphage将近 10 年前
The fact that their anticipated price is $3&#x2F;day is absurd. I can&#x27;t see insurance companies rushing to cover this.
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moron4hire将近 10 年前
I don&#x27;t know enough about this particular hardware to know. I know when I was tested for sleep apnea, the CPAP machine they suggested for me was set on a very low flow rate. A number of factors contribute to the airway obstruction in sleep apnea. One is muscle tone in the airway: too flimsy of muscle will collapse more easily. One is body fat: too much and it squeezes everything closer. One is airflow itself: if the airway is constricted just enough to create a thin slit, the airflow through it will reduce the air pressure and close it the rest of the way. Snoring is thus essentially the same phenomenon as how reed instruments produce sound. So, the idea with a CPAP machine is not to force air into your longs, it&#x27;s to create enough positive pressure inside the airway to open it again and let your own lungs do the bulk of the work thereafter.<p>But they are <i>extremely</i> intrusive to sleep, especially if you have a partner. A better CPAP machine <i>is</i> needed. But I won&#x27;t give them pre-order money, more because I&#x27;ve seen way too many bad crowd-sourcing projects than out of specific concerns towards this project.<p>For $3 I&#x27;ll buy it on a whim and try it out. I&#x27;d try a larger one that was significantly smaller than a standard CPAP for $20, maybe even $50.<p>But whether or not the project is legit is kind of beside the point to me right now. Having done a lot of prototyping of my own, in both software <i>and</i> hardware, it bothers me to see people jump directly to crowdfunding before they&#x27;ve even built a hot-glue-and-wires version of a prototype. Prove the concept. It&#x27;s not that freaking hard.<p>All they say they&#x27;ve done is built the shell of the noseplug. They haven&#x27;t any idea how to get the electronics on the inside. Their FAQ page makes it sound like their understanding of cutting edge electronics comes from Popular Mechanics, or Boing Boing.<p>People act like hardware is so extra-special hard. It&#x27;s not. It&#x27;s no more or less difficult than hacking on software in your free time. The actual, core functionality of your project, whether it&#x27;s hardware or software, should be possible to validate in less than a month. The rest of what it takes to turn any project into a real product will far eclipse the proof-of-concept work in the level of effort necessary. There&#x27;s no such thing as &quot;if you build it, they will come&quot;.<p>Okay, no, Elon Musk&#x27;s Hyperloop can&#x27;t be validated in a month. A brand-new, hyper-secure, microkernel operating system written in Rust wouldn&#x27;t be, either. I&#x27;m not saying <i>all</i> ideas are possible in a month, I&#x27;m just saying the stuff people typically do in the given spaces as garage inventors <i>are</i> on the short-scale for validation.<p>It just takes up a little to a lot more space. But if you&#x27;re dedicated, most people can find the space. I&#x27;m sure a few adults like supposedly involved in this project can rent out a small warehouse on their pocket cash together. I don&#x27;t even work full-time, I live in one of the worst areas of the country for real estate prices right now, and even <i>I</i> could scrap together the money for a small warehouse, if I had to.<p>It&#x27;s going to be hard if you don&#x27;t have any experience in hardware. Yeah, but even making a simple CRUD app is going to be hard if you don&#x27;t have any experience in software. We live in a golden age of hardware development. Nearly everyone and their neighbor in the US has a garage full of tools that could bootstrap a small industrial renaissance in a 3rd world country.<p>Or you don&#x27;t even have to buy anything, design a flat-pack vector layout in Inkscape, email it to any of the thousands of laser-cutting services in the country, tell them you&#x27;re fine buying scrap material, wait a couple of days, and you can make anything the size of a breadbox for about $50.<p>Need more complexity? Make a 3D model in blender, send it off to any of the dozens of (and growing) 3D printing services, wait a couple of days, and you can make anything the size of an old Walkman for about $50. Seriously, don&#x27;t buy your own 3D printer unless you want to get into the business of maintaining 3D printers. Outsource that malarky.<p>But come on, if you don&#x27;t believe in your project enough to put your own time and money into it, how do you expect us to believe in it? (though, I know that isn&#x27;t really stopping anyone).
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awinter-py将近 10 年前
You guys are awesome for doing this, but are enabling a dangerous kind of startup: 1. post bullshit to indiegogo 2. hackernews designs it for you 3. profit