Your point here, since it's obvious the cave isn't straight, so could get stuck? You agreeing with me but making out like your not? o_O
How much caving experience has Musk had BTW?
Whatever material used it going to weigh a significant amount, it may be light to carry upright when you have 4 guys on it, but in the confines of a tight cave even a few kilos is a lot. And something that is a solid fixed shape just adds to the problems. The power source I assume would be a battery, that certainly isn't light. (I doubt a power cable would work if they couldn't even get a telephone line in)
I'm not so much agreeing or disagreeing just inferring that there are many more facets to it - the media seem to be having a field day making out a lot of details in a way that isn't representatives of the reality giving people completely the wrong idea in some cases.
The challenge with caves like that isn't just smallness of the space but also that often an object longer than a small length will need to actively negotiate the terrain twisting, turning, etc. which is hard enough when not submerged never mind underwater - it seems they were fortunate in that regard that between diverting streams and pumping they managed to get the water levels down to where that was less of an issue than originally feared and hence why, with the forecast incoming weather, they went for it as conditions weren't going to get any better any time soon.
I've no idea how much caving experience Musk has but his comments suggest limited - hence he was bouncing ideas of the divers involved - he mentions team feedback but then says primarily Stanton.
It was designed - I'm assuming unladen - to be manoeuvrable by two people even in confined spaces though I suspect that isn't so easily done when you have a 40+Kg person inside - though they spent a good bit of time hauling the kids through on stretchers so it isn't a million miles away given the use of advanced materials to keep the weight down, etc.
I'd assuming the power source would be li-ion based or some other high energy density cell for that kind of application, the device itself wasn't propelled, and a few hours worth you are probably talking 45-100grams.
Was it actually powered? I thought it was just a capsule? Either way he's a bit of a ****, just uses any chance he can get to promote his brand. Just imagine the endless back-patting if they'd used his gadget and got them out, he'd be chasing some sort of medal no doubt.
A lot of people pestered him on twitter to get involved and he was running a few different approaches working with 3 different engineering teams including one who specialises in developing products for this kind of use (though he seems to have mugged them off a bit) - writing it off as purely a PR exercise is a bit of an injustice I think. (Though I'm not quite sure what the point of dumping the mini-sub in the cave at the end is though he made some mutterings, that I suspect will be the last we hear of it, about proving it works there or something).