Logitech F710 gamepad, allegedly contributed to Titan submersible implosion
tomshardware.com
tomshardware.com
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.
In the prior dive, a passenger hit the sub into a rock. How does that not contribute?
Really I suppose it depends on how hard and where they hit the rock, was it a failure of of the gamepad that lead to the rock hit? that is, dead controls and drifting (those infernal radio gamepads, amiright) If I remember correctly the whole sub had an outer shroud anyway. how much damage to the outer shroud was done?
Anyway, I don't really want to be the guy defending oceangate, I think a carbon fiber submarine sounds like a monumentally ill founded idea in the first place, and the move fast and break things attitude they employed in their engineering process should have never gone anywhere near a passenger. but at first thought, at the speeds the sub moved I doubt a rock hit would damage the sub. if I had to bet, it was plastic deformation leading to delamination and fatigue.
Showing Rush tossing the controller while saying "it's bluetooth so I can hand it to anybody... it's meant for a 16 year old to throw it around and super durable" is powerful imagery for a jury.
The complaint specifically mentions Bluetooth, which I can't tell if it's an error. They switched from the DualShock controller used in Cyclops I, which does use Bluetooth. There is probably a reason they switched wireless technologies (Bluetooth is even worse than Logitech's 2.4 GHz wireless), which if not documented, could also show negligence.
Your carbon fiber hull fatigue theory is interesting.
I picture it sitting out in the hot sun and cold nights for months. It reminds me of the CNA building in Chicago, where windows fractured due to uneven sun exposure. The owners didn't replace them until one fell and killed a pedestrian, resulting in an $18 million settlement in 1975.
Be careful: are you trying to predict legal results, or find truth? Those are (unfortunately) rather different questions. If you're looking for truth, you don't care about what makes "powerful imagery for a jury".
BTW, the "carbon fiber hull fatigue" theory is not GPs, it's the extremely obvious top candidate for the failure.
Anyway, there is still no evidence that using a gamepad had any concrete negative effect. Letting passengers drive? Yeah, that's a problem. But it would be at least as big a problem with industry standard controls, which wouldn't even have the faint advantage of familiarity.
Anyway, the best sense I can make of your logic is that designedByStudents -> gamepad, and designedByStudents -> negligence, therefore gamepad -> negligence. In that case I believe your fallacy is "affirming the consequent", with a side of ad populum w.r.t other submarines. I don't see how changing the type of controller fits in.
This thread is about the gamepad. The lawsuit mentions it. It's relevant. Period.
So then the most important question relating to the gamepad remains: why do people keep mentioning it? The specific sub thread we're under started with a pretty good theory IMO.
In the meantime, the correct thing is in fact to dismiss the gamepad until any evidence appears relating to its role in the vehicle loss, and not to get to excited for that to happen.
> The lawsuit acknowledges the root cause of the implosion may never be known and does not place sole blame on any one factor.
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.
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.
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.
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.
the walls have to be strong(thick) enough to withstand the pressure (this is obvious, I know)
the ratio of wall thickness to void(crew) space determines reserve buoyancy.
smaller submarines are stronger than bigger ones. but have a worse buoyancy ratio.
The end result is that as you design a submarine to go deeper it has to become smaller with thicker(heaver) walls until past a certain depth it goes negative buoyant and will sink. So you have to add additional buoyancy. not a trivial task given the pressures involved. the Trieste(first submersible to the challenger depth) was built like a blimp, with a tiny crew sphere hung below a massive tank of oil(they used oil because it is lighter than water and will not compress).
So a lighter material hull is very desirable, it makes the whole operation much easier. They probably should not have been testing it on commercial passengers however.
This is also the benefit of titanium, it is almost as strong as steel with half the weight.
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.
https://www.theverge.com/2018/3/18/17136808/us-navy-uss-colo...
(Edit: added link to video)
“This part wasn’t adequate for the task!” “Well, yeah. Our Submarine Parts division doesn’t sell their stuff at Target.”