I am worried that externally caused vibrations might damage my HDDs (NAS in the planning). The subway / metro runs under my building, and every time the train passes, this causes slight but measurable vibrations in the 50-100 Hz frequency range. It is more like a rumbling noise than the usual vibration of a passing train....
I believe it doesn’t really matter much whether you want to protect the environment from vibrations of the machine vs. protecting the machine from vibrations of the environment - in both cases, decoupling the systems is what you want to achieve.
I personally had to deal with the case of a large format CNC machine transferring stepper motor vibrations into an adjacent office via the wall-mounted brackets it was sitting on. People started to complain shortly after installation since the noise was very audible in the otherwise quiet working environment.
The solution involved placing the machine on a plate mounted via rubber decouplers (see www.dayco.com/en/product/decouplers) which in turn was mounted to a shop-built TMD using a rubber core sandwiched between two foam plates. The rubber core works as both mass and absorbs additional vibrations. It was built following a paper, but unfortunately, that was around 7 years ago and I’m not sure I’ll be able to dig the publication out again.
You can in fact simulate the TMD and do the tuning (see for example mathworks.com/…/mass-spring-damper-in-simulink-an… , though dedicated software packages also exist) but in all honesty, that will probably be overkill for your case.
Having your NAS sit on a 1/2" board of baltic birch plywood resting on a foam sandwich is probably going to do the trick in your case. You can easily create such a sandwich using foam, a rubber mat and some spray glue. Different foam densities will give different results and yield different “tunings” - you may have to play around with this a bit. I could imagine you’ll most likely even be able to skip the second decoupling step (rubber feet/decouplers), in the aforementioned case the second decoupling allowed for another set of frequencies to be dampened (via a different overall rubber hardness) but also brought overall amplitude down.
Don’t use super soft foam, as this will yield a wobbly base, something you probably want to avoid for your NAS. Also, make sure not to attach the base board to anything else apart from the foam, or you’ll transmit vibrations again. If you don’t like the appearance of the foam, you can build a small fence around it that goes up to the top of the base plate.
All that being said, there are also ready-made solutions like speaker dampening feet available: www.amazon.com/…/B09QC2L7N3
Most of them are made to decouple subwoofers, so they might fit into the frequency spectrum you specified. Those couls certainly be an affordable and rather quick way to solve the problem.
Honestly, I think your approach using the MEMS accelerometer in your smartphone is fine - just make sure to tape the back of your phone firmly to the board to get a rigid connection. This will be of particular importance if you want to do any kind of tuning, as you might measure spurious frequencies if the device is not properly attached.
Smartphone accelerometers are actually used in civil engineering / industrial applications to determine frequencies of e. g. bridges or check for bearing wear. If you are interested, here are some papers:
That being said, the accuracy of the frequency readings is not super important for your application, as what you are after is pretty much only a reduction in amplitude. I would assume spinning hard drives show different responses to different vibrational frequencies, but I did not have the time to research this myself. However, here are two papers that explore what you are trying to do, which I will link since they also mention a few related papers that show the impact of vibrations on hard drives:
This would in theory incentivise to optimize dampening certain frequencies, but I suspect you will quickly get into the realm of overengineering / premature optimization, as the dampening might be good enough to tune out all relevant frequencies without simulations or tuning etc. However, it’s still certainly a worthwhile effort for educational purposes though.
As for a practical approach, I’d probably simply start out with some super cheap foam obtained at the nearest home improvement or crafts store and see how a sandwich using that affects signal amplitude. You could even introduce artifical vibrations using a DC motor with a weight mounted off-center on the shaft, which you can get ready-made for next to nothing on eBay (“vibration motor”, ~ $2).
If you want to get into tuning / experiment / analysis territory, I would like to include additional motivation. Not only might proper decoupling increase the lifetime of your drives, but it could also improve performance. I will include the following video as humorous proof of that:
P.S.: I firmly believe that research should be freely accessible, so I feel obligated to mention that all papers linked above are, if not available for free on their respective webpages, obtainable via a certain scientific hub.
Hey, great that you chimed in, I agree with the points you’re making. As for my remark regarding amplitude, what I wanted to convey was: in the measurement scenario using the PhyBox smartphone app, OP should see an overall smaller signal envelope if the NAS was properly decoupled, compared to the previous plot.
As for your comment regarding the Nyquist theorem, PhyBox maintains a list of devices and their sensors so it would be possible to lookup the available sampling frequency. There are other factors potentially limiting the sample rate (e. g. switching offl microphone access for the app on Android), but it’s a good starting point.
That’s not supposed to be solved by censorship, though, as that affects people who DO want to see random, artificial dicks flailing around, and your personal preferences should not forcefully be applied to everyone, right?
If it has dicks flopping around in the wind, it should be marked as NSFW, and your client should be set to blur and/or filter those posts. That solves the issue amicably for all parties.
I ran Manjaro Linux as my daily driver a few years ago but slowly phased it out for Windows for some reason, and I’m finally back using Linux (currently Linux Mint). I gotta say, I don’t know why I ever switched back to Windows. There’s just so much freedom Linux gives you right off the bat that Windows is just plain...
I used to be a Windows system developer, think device drivers etc. for what, 20 years? I switched to Linux 18 years ago and never looked back - the whole dev experience is a lot more pleasant, more control, reasonable tools and software installation, proper customization etc.
I believe you didn’t have a Linux problem, you had a problem with hardware manufacturers being fussy about enabling development of proper support for their hardware. Why not look into hardware that is actually readily compatible with Linux? Tuxedo Computers are often recommend, I used to run a Clevo and had a great experience as well.
Hm, I never had any hardware issues in the last ~10 years, but don’t get me wrong, I hear you. I absolutely believe that it is possible to find a combination of HW and SW that will simply not work for a particular use case, and if my productivity would be threatened, I’d also switch in a heartbeat. In fact, I’ve gotten so used to the customizations Linux offered me that I can’t even imagine working on another Linux system without my setup and dotfiles - a different kind of vendor lock-in, if you will.
Anyway, just wanted to put a brand out there that offers some guarantees when it comes to hardware support, in case you (and others) might not be aware of such vendors.
Soap (lemmy.world)
Protecting HDDs from (external) train vibrations
I am worried that externally caused vibrations might damage my HDDs (NAS in the planning). The subway / metro runs under my building, and every time the train passes, this causes slight but measurable vibrations in the 50-100 Hz frequency range. It is more like a rumbling noise than the usual vibration of a passing train....
2 January 2024 (sh.itjust.works)
Baldur’s Gate 3 Slyly Adds Jiggle Physics For D**ks, Balls (kotaku.com)
‘Hey batta batta, hey batta, hey batta batta, swing.’ — Larian, probably
I finally switched back to Linux as my daily driver after a couple of years of being on nothing but Windows.
I ran Manjaro Linux as my daily driver a few years ago but slowly phased it out for Windows for some reason, and I’m finally back using Linux (currently Linux Mint). I gotta say, I don’t know why I ever switched back to Windows. There’s just so much freedom Linux gives you right off the bat that Windows is just plain...