[HN Gopher] Logitech F710 gamepad, allegedly contributed to Tita...
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Logitech F710 gamepad, allegedly contributed to Titan submersible
implosion
Author : type0
Score : 16 points
Date : 2024-08-11 19:58 UTC (3 hours ago)
(HTM) web link (www.tomshardware.com)
(TXT) w3m dump (www.tomshardware.com)
| q_andrew wrote:
| Something I noticed in the lawsuit (complaint 5.12) I haven't
| heard mentioned about this story:
|
| _Other than TITAN, no commercial manned submersible has ever
| suffered an implosion (only early military submarines have done
| so)._
|
| That's a pretty damning statement if true. As a land-dweller, I
| thought implosion was the main concern when using new submarines.
| jmount wrote:
| I think the idea is: implosion is so scary they work really
| hard to engineer it out (as long as you don't go beyond your
| max depth).
| actionfromafar wrote:
| _" The carbon fibre and titanium, there's a rule you don't do
| that. Well, I did."_ (Found the quote on WikiPedia.)
|
| It seems insane to me. It's easy to be an armchair anything,
| but I don't understand why you would do such a thing. It's
| not like a submersible needs to be light weight, either.
| ethbr1 wrote:
| I believe because it was substantially cheaper to fabricate
| than a traditional metal hull.
| rich_sasha wrote:
| It is insane, but not _entirely_ pointless. A metal
| submersible is heavy and negatively buoyant, whereas you
| want it to be positively buoyant (then add removable
| ballast).
|
| The way you add buoyancy is expensive fancy aerated
| concrete, or something like that, and a lot of it, since
| it's not that buoyant. But it is pressure resistant.
|
| By making it out of CF, you save on that cost.
|
| Not a worthwhile cost cutting exercise but at least there
| is some reason for it.
| sitharus wrote:
| It is, so it's taken really seriously. The hulls are made from
| material with well characterised gradual failure modes -
| bending and deforming rather than sudden failure. This means
| metals with thoroughly inspected welds and joints to ensure no
| internal voids, and a process of gradually diving deeper to
| check the hull meets the design requirements.
|
| Using materials that fail plastically and gradually increasing
| depth trials means the failure mode is hopefully deformation
| rather than complete failure, and will happen at the highest
| depth as possible so a quick surfacing can be achieved.
|
| Submarines, along with space, are an area where innovative new
| methods need a lot of testing before you commit human life to
| it.
| jemmyw wrote:
| If I remember the early reporting correctly, this submarine
| had plastic deformation on every dive. So it was already
| failing, they just didn't do anything about it.
| dlachausse wrote:
| The Navy uses Xbox controllers in some of their submarines...
|
| https://www.theverge.com/2018/3/18/17136808/us-navy-uss-colo...
| syvanen wrote:
| Yes, as one way to control cameras on top of masts. Replacing
| periscopes. Not really a comparable to actually steering the
| boat. Here's a video from a submarine tour where you can see
| the Xbox controller in action:
| https://youtu.be/0StWrXoN8nI?si=Hf5eoGOU-jxDNa2x
|
| (Edit: added link to video)
| meowster wrote:
| Pretty good video if anyone wants to watch it all the way
| through, otherwise the Xbox controller part starts at 8:38.
| jmount wrote:
| I thought one of the narratives was that Nargeolet was a
| depressed Judas-goat used to bring in the other passengers.
| andrewflnr wrote:
| There's no new evidence in the article, about the gamepad
| specifically or anything else as far as I can tell. We've already
| argued the implications of the gamepad a dozen times over.
|
| > The lawsuit acknowledges the root cause of the implosion may
| never be known and does not place sole blame on any one factor.
| teruakohatu wrote:
| With so many other factors that contributed to the implosion in a
| big way, this detail seems insignificant.
|
| It was a cramped vessel, wireless may have been safer because
| nobody could yank a cable out, or get twisted up in a cable. It
| was probably communicating wirelessly over a couple of feet or
| less in a RF interference free environment.
| kstrauser wrote:
| If so, I feel bad for Logitech about that. I don't recall them
| advertising for that use case.
|
| "This part wasn't adequate for the task!" "Well, yeah. Our
| Submarine Parts division doesn't sell their stuff at Target."
| somat wrote:
| It keeps being brought up. I suspect as a sort of character
| assassination technique. Sort of the disaster analysis version of
| bike-shedding. "well I don't know much about the physics of
| carbon fiber in high pressure environments, but I know a cheap
| gamepad when I see one." However, I expect that such a commercial
| off the shelf gamepad to be probably the most reliable well
| tested piece of equipment on the sub. it is highly unlikely to go
| bad and is super easy to carry a spare.
|
| Also no analysis I have seen actually knows how the sub was
| controlled or bothers to explain how you would do it better than
| a gamepad. If I had to guess, the motors and ballast controls
| went into an array of controller boards in a rack somewhere. the
| control circuity(probably something like i2c or canbus) tied into
| a central microcontroller. and then a laptop or tablet is used
| for the human IO(gamepads and screens). There probably was not
| much redundancy in the system, but I am not sure that is a bad
| thing, redundancy massively complicates the design and introduces
| new error conditions. (look into the causes of the US Navy
| destroyer John S. McCain collision, it was a highly redundant
| controller system. and the helmsman failed to realize he had no
| control, it was really a training issue) often it is better to
| just have the ability for manual control. that is, go back to the
| rack of motor controllers and manually start twisting knobs and
| jumping wires. but none of this matters, because it is not what
| failed.
|
| It cheapens the narrative to go after stupid superficial things
| like the gamepad, that did not cause or contribute to the fault
| rather than what actually caused the engineering failure.
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(page generated 2024-08-11 23:02 UTC)