The solution for the above is that you need to take into account the radius of curvature and you're clearly not doing that. The inside of that tube needs to be relatively smooth in the direction of travel, not perpendicular to it. You could also interleave to two segments if you wanted it to be even smoother.
So no, this is not a hard problem in spite of your continued insistence that it is because you can't solve it.
And I still don't understand how your solution wouldn't leak air into the hyperloop unless the steel sleeves were pressing very firmly into each other. Like the inner sleeve forcefully pressing into the outer sleeve.
I have no idea why you refuse to admit this is at the very least a nuanced problem.
I'm not on your payroll and you're stuck in a groove.
> But I have some strong words which, out of respect for HN's guidelines, I won't say.
Feel free, I'm not made of sugar. But you're arguing from a position that makes no sense to me, you're apparently entirely ignorant of the basics of mechanical engineering and you're going to tell the likes of Elon Musk and his band of merry engineers what they can or can not do. They just came within a hair of planting a friggin' rocket on a barge from space. Do you really believe they couldn't get a bunch of tubes to slide inside each other without overshooting their air intake budget? That's mostly a factor of 'how big are the pumps' and 'how many such sliding spots do we need' (a few hundred would do just fine) and how much room there is for additional seals (plenty).
> And I still don't understand how your solution wouldn't leak air into the hyperloop unless the steel sleeves were pressing very firmly into each other. Like the inner sleeve forcefully pressing into the outer sleeve.
No, you don't need that you can use regular seals for that, just like we do on high pressure air connections, fun fact, they work better when the difference is higher, go figure.
> I have no idea why you refuse to admit this is at the very least a nuanced problem.
Because it is a nuanced problem for you, but not for anybody that has the wherewithal to be hired on the engineering parts of a project like this. Just like my little brother would find assembly language a 'nuanced problem' and I find it relatively easy. It all depends on whether or not you're doing this (mechanical engineering) on a daily basis or whether you want to be back-seat driving nay sayer. Once you've decided on the latter any solution will be inadequate.
Best of luck to you. Keep making awesome things.
What else do you want? A blueprint? A cad design?
Thanks for the pieces you've provided so far. I'll bring up my objections elsewhere. Hopefully anyone who's been having my same concerns will be able to do the same.
You argue that something is impossible but at the same time you outline your ignorance. The normal position for being ignorant is to study the subject, not to argue that something is impossible.
It's like saying a moonshot never happened because you couldn't do it yourself. There are lots of things that each of us individually can not do, but collectively we can do amazingly complex things. The specialization required takes time and effort. If you're unwilling to put in the time and/or make the effort then you should not take up positions that tell those that did make that effort what they should not be able to do according to you.
If mechanical engineering interests you then maybe you should go and study the subject rather than to take up strong positions like these and to be rigid in your inability to shift on those positions.
> I'll bring up my objections elsewhere. Hopefully anyone who's been having my same concerns will be able to do the same.
Basically that says that you want to argue, not learn and that you'll only take what agrees with your viewpoint.
But no, actually, you smashing huge holes into my logic was exactly what I was hoping for, because that's how ignorance is transcended. I dislike both the peanut gallery and peanuts, so I think I came across wrong. Starting the conversation by vaguely disparaging your merry band of engineers probably wasn't great, but my mind's malleability is play-dough, definitely not steel.
Finding someone who agrees with my viewpoint is the most useless thing, both to me and to anyone that might be reading the conversation. Someone with an ability to point out why I'm wrong and to actually debate with me is both rare and valuable.
Please try to understand that some people find the basics interesting, so even though you're saying you don't, it's important to kindle that spark. (I still don't see how this is basic, since the entire SpaceX engineering team somehow missed your segmentation approach, or considered it and chose not to pursue it for some reason, but you're probably right. And I have other qualms about the approach, but I don't really trust re-opening this debate without some kind of mutual understanding that we'll focus on the ideas in the debate, not on the people involved.)
Also, curves still result in a speedbump with that solution. The pod will be traveling directly toward the gap just below "seg2" if it's banking against the wall. You could make the edge a sharp edge, like a sword's edge, but that doesn't help because due to expansion that edge will still protrude out into the path of the pod.
I know it seems like it shouldn't be a hard problem, but it's looking like one. Remember, 300 meters of expansion over 350 miles is 0.85m of expansion per mile. Hold out your arms to the length of a meter and picture how much steel that is. That's what your proposed joints need to deal with: 0.05cm of expansion per meter. So if you have your joints every 20 meters, that's still a 1cm gap, which means a speedbump around curves. Wouldn't that make curves very unpleasant for the passenger and the pod? And you can't have them every meter without increasing the engineering complexity and weakening the structural integrity, right? Yet whatever solution they come up with would need to be placed less than every 20 meters, otherwise they'll get a 1cm gap.