5 ms·
Are they solid state? I thought the accelerometers were, in fact, essentially tiny boxes with a ball in with some springs? See https://en.m.wikipedia.org/wiki/M
by alexchamberlain 6y ago
Are they solid state? I thought the accelerometers were, in fact, essentially tiny boxes with a ball in with some springs? See https://en.m.wikipedia.org/wiki/Microelectromechanical_systems https://en.m.wikipedia.org/wiki/Microelectromechanical_syste... ; I can't actually find a decent reference specifically for MEMS accelerometers.
- polishdude20 6y agoTechnically yeah they are literally a tiny weight on springs. But they are in a tiny silicon package that is effectively "solid state"
- _-___________-_ 6y agoSolid state doesn’t mean “tiny”, nor “packaged in silicon”. A thing with moving parts, no matter how small or hidden, is not solid state.
- MauranKilom 6y agoYou can model it as a spring, but it's not a spring in the slinky sense - it's just a thin piece of material whose electrical properties are affected by tiny changes in stress/strain. Its operation fundamentally involves (near infinitesimal) movements, but then so does a cell phone pole. I don't see what we gain with debating its "solid stateness" (especially when hedged with "effectively"). Maybe you could point to some effect that this distinction implies?
- supernova87a 6y agoThat gets to be a nitpicking distinction when you get to the level of micron moving parts. If a practical definition of solid state is that something can survive, say, 20G of abuse, then an accelerometer in silicon, even with moving parts, is pretty indistinguishable from true "solid state".
- boxfire 6y agoSolid state as a term is a discipline of materials, practically speaking it's a bad idea to overload it with your imprecise generalization. Solid state as mentioned above specifically refers to a lack of moving parts (even at a micron level). In this space without multibody dynamics some wave properties are determinable in a much more deterministic sense.
- krastanov 6y agoYour semantic prescription does not seem to be the common semantic prescription in electrical engineering. MEMS seems to be typically called solid state for the reasons mentioned by OP. Example in practice (second paragraph): https://www.analog.com/en/technical-articles/mems-accelerometers-for-condition-monitoring.html# https://www.analog.com/en/technical-articles/mems-accelerome...
- Reelin 6y agoQuartz crystal oscillators make use of the piezoelectric effect. Do they not qualify as solid state? For that matter, capacitor whine is due to electrically induced mechanical vibration as well; I've never heard anyone claim they don't qualify as solid state components though. To me, moving parts generally refers to physically coupled but distinct pieces that move relative to one another. Otherwise heating anything that contained a piece of metal by a few degrees would disqualify it.
- xxs 6y agoElectrolyte caps are not solid state and they leak - likely the most common electronic failure. I have not heard of ceramic or polypropylene caps whine. OTOH coils are solid state and they are a lot more common to cause 'whine' than any type of capacitors.
- Someone 6y agoA transistor has moving parts: electrons. More importantly, https://en.wikipedia.org/wiki/Solid-state_electronics https://en.wikipedia.org/wiki/Solid-state_electronics: ”The term "solid state" became popular in the beginning of the semiconductor era in the 1960s to distinguish this new technology based on the transistor, in which the electronic action of devices occurred in a solid state, from previous electronic equipment that used vacuum tubes, in which the electronic action occurred in a gaseous state.” ⇒ the term doesn’t reference the hardware being solid.
- srtjstjsj 6y agoFrom the second sentence in your linked source: "The term is also used for devices in which semiconductor electronics which have no moving parts replace devices with moving parts"
- dekhn 6y agoSolid state really refers to not using gas plasma (vacuum tubes). Personally I would call MEMS devices like this solid state, even though it has moving parts. Everything in it is in the "solid" (physics solid) state, there is no liquid or gas involved.
- srtjstjsj 6y agoThen why is my 5400 RPM HDD not an SSD? Wikipedia: > The term is also used for devices in which semiconductor electronics which have no moving parts replace devices with moving parts, such as the solid-state relay in which transistor switches are used in place of a moving-arm electromechanical relay, or the solid-state drive (SSD) a type of semiconductor memory used in computers to replace hard disk drives, which store data on a rotating disk.[6]
- dekhn 6y agoHard drives probably count as solid state, except the interior is filled with an inert gas, so they're really a mixed phase system. In short: neither the term definition nor usage is entirely consistent.
- supernova87a 6y agoHere's an actually entertaining video on it: https://www.youtube.com/watch?v=KZVgKu6v808 https://www.youtube.com/watch?v=KZVgKu6v808 (the rest of the channel's videos are good too -- the aluminum can video is great)
- sleazy_b 6y agoThat was really great and explained it really well, thanks!
- dylan604 6y agoSo, how well would a smartphone work on the Moon or Mars? (ignoring the fact it is not shielded for cosmic radiation). If the spring&ball accelerators are measuring the effects of gravity, would they notice the rotation when a != 9.81m/s/s?
- scottlocklin 6y agoThe way the asics were written in 2000 it should work. Should work in free-fall also.
- MauranKilom 6y agoIt's not a ball with looping-wire springs in any sense. That's just a model/illustration of the measurement principle.