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Comment: And let someone into my garage? (Score 3, Interesting) 85

by Nutria (#48889155) Attached to: 'Never Miss Another Delivery' - if You Have a TrackPIN (Video)

Two thoughts:

1) How do you get the one-time TrackPIN to the UPS guy before the fact?

2) Way back when the milkman delivered his eponymous product, there was a small "airlock" built into many houses, with doors open both to the outside and the in. Some sort of mechanism could be developed so as to deliver the package from the airlock to the house.

Comment: Re:"plenty of flat land to go around (Score 0) 165

by Nutria (#48828253) Attached to: Elon Musk Plans To Build Hyperloop Test Track

In your fevered dreams!"

Said who? It costs the same as a BMW 535i, yet only goes 265 miles. That's *not* revolutionary.

Call me back when he's got a $25K minivan that can go 300 miles at 80MPH while carrying 4 people and a whole lot of stuff. That will be revolutionary! Maybe my teenagers will be able to buy such a vehicle. But I doubt it.

"Beating Ares 1 to the ISS for 2% of the development cost, on a rocket cheaper than the Russians and the Chinese,

Using an engine designed by someone else using taxpayer money is IN NO WAY SHAPE OR FORM revolutionary.

It's great engineering and no-nonsense construction from a company that hasn't (yet) become bloated by sucking on the DoD & NASA teats, but that is *no* revolutionary.

For it to be revolutionary, they'd have to come up with something *really* game changing, like... a fuel better than LH2/LOX which doesn't corrode everything it gets near, or spray radioactive death half-way across the countryside.

Practical, reusable rocket engines (where you don't have to strip down and rebuild the engine every time like they did with the SSME are stupendously important, and I hope SpaceX can get that working.

However, and sadly, getting a booster to land on a floating platform is "mere" engineering: throw enough time, money, sensors, accelerometers, actuators, etc -- IOW, stuff that we already have and know how to use -- that's not revolutionary.

A *real* revolution would be to find

So, while Musk is doing some important work

Comment: Re:"plenty of flat land to go around (Score 1) 165

by Nutria (#48828055) Attached to: Elon Musk Plans To Build Hyperloop Test Track

Hyperloop is a system involving partially evacuated (not hard vacuum) tubes.

The air on the outside is still going to *aggressively* want to rush in through any little crack.

it involves magnetic accelerator segments for propulsion.

Let me see if I've got this straight: we can't build regular maglev trains because they're super-expensive (the engineering, construction and maintenance would be incredibly difficult), so... we'll just make it that much harder by wrapping a (partial) vacuum tube around it???

You've got to understand that as much as Europe loves it's trains, there's a reason why high-speed trains aren't draped across the continent: the tracks have to be *perfect*, and they're always stopping and starting; even the express trains don't get up to full "steam" for very long stretches.

There's a reason that autobahns/Interstates are such a great idea: they combine all the benefits of an express train, with the flexibility of a two lane road (if you're near one, there's an on-ramp close by). And when you get "there", you still have your car to drive around in.

So, no. If maglev was a good idea, it would have already been built.

When it is incorrect, it is, at least *authoritatively* incorrect. -- Hitchiker's Guide To The Galaxy