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Submarine missing near Titanic used a $30 Logitech gamepad for steering

arstechnica.com

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Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#211
post #13

My 11yo son asked me why they did not connect a buoy to the submarine with a string. Lol

I guess perhaps there’d be a risk of the string getting tangled in the wreckage of the Titanic.

But then surely you could just cut the rope and free the vessel.

I think your son is onto something!

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#213
post #196
post #111

Earlier quoted context omitted.

Exactly what's the issues, then?

buying wrong COTS components, ones that are not fit for intended purpose

> buying wrong COTS components, ones that are not fit for intended purpose

What could possibly lead you to presume that? Do you feel in a better position to make that call than all the engineers who actually work on that task at a professional level?

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#214
post #3

The US Navy uses an Xbox 360 controller in active service [0] Mass market has a lot of R&D to leverage so it makes sense. Nothing to say this is the cause of the fault and probably going to be more reliable than something hand rolled. [0] https://www.theverge.com/2017/9/19/16333376/us-navy-military...

xbox 360 controllers last only 6 months to a couple years with various failures that don't matter when you're playing a video game with them but can actually get you killed if they fail when you're in deep ocean. These are not ok for controls in vehicles where failure can mean everyone onboard dies. The navy does not use these for critical system controls. They were never built or tested for that.

They do for drones. But plenty of spares available.

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#215

With all the talk about failure modes of carbon fiber, the scariest part of this article is the photo of the display and light held up by screws drilled into the side of the pressure vessel.

I heard an anecdote at one point that when a submarine depressurizes that deep, everything inside gets pushed through whatever hole caused the depressurization, like squeezing the contents out of a tube of toothpaste.

Might have been from the Byford Dolphin accident: https://en.wikipedia.org/wiki/Byford_Dolphin

"Hellevik, being exposed to the highest pressure gradient and in the process of moving to secure the inner door, was forced through the crescent-shaped opening measuring 60 centimetres (24 in) long created by the jammed interior trunk door. With the escaping air and pressure, it included bisection of his thoracoabdominal cavity, which resulted in fragmentation of his body, followed by expulsion of all of the internal organs of his chest and abdomen, except the trachea and a section of small intestine, and of the thoracic spine. These were projected some distance, one section being found 10 metres (30 ft) vertically above the exterior pressure door."

I wonder if anyone knows if this universally true? Would the inhabitants of this submarine have experienced a similar fate if one of those bolts failed or a hole in the hull developed?

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#216
post #191

I wondered why they can't install a GPS anyway on the sub so that when it eventually does get to the surface, at least they can be found then.

Why would it eventually get to the surface? The issue with submarines is that they don't normally float (and if you need them to have positive buoyancy, they have to be functional).

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#217
post #209

Earlier quoted context omitted.

Its practically impossible to do satellite to undersea communications. Being underwater does all kinds of hell to RF signals. Even just reliably doing undersea to surface communications is pretty tricky. Is your phone waterproof? Stick it a sink full of water. Watch it lose all network connectivity.

See my previous comment [0]: "that would release some sort of buoy, that would float to the surface and start transmitting with gps etc." That should work if it's floating I would think? [0] https://news.ycombinator.com/item?id=36409802

I wonder what the drift would be like if you released a buoy 2 miles below the surface. You could theoretically have the last estimated location of the sub, but even then that's largely an estimate as its not like the sub actually has a GPS fix its all dead reckoning.

They already know about where the sub should be, somewhere around the Titanic wreck. If an untethered buoy pops up a few miles away, does it really do much to help clue you into where they are? And if its not much to put a tether on the buoy, why not just have the craft be tethered from the start?

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#219
post #164
post #16

Earlier quoted context omitted.

I personally believe using mass market makes sense. I don't understand the criticism I've seen on this website for using off the shelf controllers or camping lights (what do you expect, an LED strip magically engineered by a large aeronautics firm specifically for the sub? and what would that change?). That being said, the difference between a Microsoft controller and a third party is that Microsoft very certainly di…

Logitech is a "cheap third party"? I like MS hardware, but my goodness, calling Logitech that is clearly missing something in the accuracy department. Logitech is way more experienced at making and selling input devices than MS.

I thought both companies started making mice at about the same time.

Re: Submarine missing near Titanic used a $30 Logitech gamepad for steering

#220
post #3

The US Navy uses an Xbox 360 controller in active service [0] Mass market has a lot of R&D to leverage so it makes sense. Nothing to say this is the cause of the fault and probably going to be more reliable than something hand rolled. [0] https://www.theverge.com/2017/9/19/16333376/us-navy-military...

> The US Navy uses an Xbox 360 controller in active service To control periscopes (“photonics masts”), and some other equipment, not for primary control of manned vehicles, that I can find any indication of.

The YouTube channel SmarterEveryDay was invited to film on an Ohio class nuclear submarine training in the Arctic. [0] You can see how many of the system are mechanical and not electronic in the demonstration especially the ballast controls. Most if not all boats and ships can control the throttle mechanically so if the boat loses its electronics such as a wave smashing the windshield in, it is still possible to control the rudder and throttles. I was very surprised at the lack if mechanical controls on the recreational submarine.

[0] https://www.youtube.com/watch?v=XFJnWp1tAdU

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