[Teaching & feedback] Copernicus - Space Science Laboratory

[Artlav]

http://copernicus.exosphe.re

Friends of mine are going to be running a learning camp in Budapest this July, themed around building a space elevator.
Not just any space elevator, but the one that is using the spoils of space mining going down to power the lifting of the payloads.

However, building it is not the goal (duh ), the goal is to use the concept as a case study for getting people interested in space science by giving them an exciting problem.
Trying to bridge the gap between research and business along the way.

Naturally, there will be orbital mechanics involved.

It didn't took much to convince them that we need Orbiter.
I ran a quick survey among them, which showed a lack of common sense about space flight that any orbinaut would have.
I.e. that you need to burn retrograde (instead of down) to get back to Earth from the ISS.
It's curious how one can know all the theory, but have no real intuition about how things work up there.

Orbiter is a perfect tool for giving that kind of intuition, for letting people play around with spaceships and see for themselves how things work.
Quite likely i will be there to run a basic course of orbital mechanics and spaceflight misconceptions, centred around Orbiter.

So, we are looking for feedback.

-The broad question of what do you think of the whole idea?
What sounds good, what sounds like it should be improved?
How much sense does the site makes? ( http://copernicus.exosphe.re )

-Any advice (or experience stories) on how best to use Orbiter to teach the common sense of spaceflight?
There will be quite a bit of technical people, but some relatively clueless ones as well.
The idea is to help people develop newtonian intuition, the ability to predict what would happen with a manoeuvring spacecraft in the same way they can predict what would happen to a manoeuvring car.

My idea was to give them the survey, then demonstrate with Orbiter what would happen for every wrong answer, with a running commentary on why and how.
There will also be a simpit corner, and everyone will be welcome to install Orbiter on their laptops.

-And if you like it, you're welcome to apply while it's only $650 for the three week program.

 

[boogabooga]

I'm trying to understand the concept of the space elevator.

So, let me get this straight. You send a satellite or something up the elevator to geostationary orbit, and this takes energy. Then, you capture some mining payload from orbit and expect to return it to earth while converting the potential energy and storing it to power the upward trips.

I can see right away that you would need 100% efficiency to pull this off. But there will be losses in both directions. Even as the best case you will only get a fraction of the energy you need to power the elevator.

Or have I misunderstood?

 

[Artlav]

Then, you capture some mining payload from orbit and expect to return it to earth while converting the potential energy and storing it to power the upward trips.

No, you don't store the energy.
Mined stuff goes down, generating energy.
Payload goes up, consuming that energy.
Storing would just waste power.

No need for 100% efficiency either - you can just send more mass down than what you will be lifting.

Imagine it that way - there is a small asteroid parked near the geostationary station. It's being constantly streamed down on one tether (or one side of it), while the payloads are being lifted on the other one.

At least that's how i understand the idea.
The main exercise for the participants would be to actually figure out all these details.

 

[Ravenous]

It's being constantly streamed down on one tether (or one side of it), while the payloads are being lifted on the other one.

Just a thought... I've always been interested in the elevator idea (who hasn't?) but a problem is - if you lift or lower a single payload - there is angular momentum there, so the cable will have a tendency to deflect forwards as an item is lowered, or backwards as it is raised.

If there is a cable loop with pulleys (and that is an assumption!), how would we stop them colliding? Mount them side by side? What torque will this exert at the top or bottom of the loop? Can distributing the load (lots of small parcels on each run of the cable) reduce the tension on it?

(Just speculating, as I certainly haven't tried to analyse this in any sort of detail.)

 

[Ripley]

...Any advice (or experience stories) on how best to use Orbiter to teach the common sense of spaceflight?...

This whole story about a space elevator is too much for me, and I'll leave it to the experts.

But one thing above all (and I'm talking to the creator himself!): Videnie.

:tiphat:

 

[PhantomCruiser]

Pretty cool concepts. The web site seems pretty straightforward.

As far as orbital "problems"

Something that tripped the kiddo out the first time she messed around in Orbiter was just flying the R-Bar. It was easy enough for me, but something about it was counter intuitive for her on her first time out. She got the hang of it by using the Shuttle-A docking scenario a few times. It wasn't too much later she could do fly-arounds without any trouble.


I've not messed around much at all with Yuri's Space Elevator, it seems that I've always had other things on my mind, but...

A potential scenario I see; Starting from the top of the elevator a crew takes their ship to a satellite in geostationary orbit. Crew must rendezvous, grapple (using URMS attached to Shuttle-A maybe?), EVA (UMMUFA works, or Dan's UCGO modded Shuttle-A (even better?), grapple to said satellite and spend some simulated time "making repairs", return to craft, and return to elevator (or Brighton Beach, that'd make additional problems/solutions)

Using a DGIV, deploy George's ScopeSat (version 2) to lunar orbit. Starting at the top of the elevator.

Maybe a scenario where an asteroid at the L1 or L2 (or anywhere) is being harvested, and a Shuttle-A has to bring cargo from the asteroid to the top of the elevator. The problems include a plane change and orbital synchronization, rendezvous and docking.

Just some stuff that popped into my head. It certainly looks like a fun workshop.

 

[Artlav]

how would we stop them colliding?

I think they should separate naturally - one would tend to lag, while the other would tend to overtake.
Assuming two tethers there.
It should be fairly straightforward to keep the system in tension by running stuff up and down constantly. Even if there is nothing to launch, you can raise dummy payloads, and then drop them down at a small cost (hopefully the efficiency would be rather high).

But one thing above all (and I'm talking to the creator himself!): Videnie.

Certainly.

Something that tripped the kiddo out the first time she messed around in Orbiter was just flying the R-Bar.

Interesting.
I haven't thought of that.

Maybe a scenario where an asteroid at the L1 or L2 (or anywhere) is being harvested, and a Shuttle-A has to bring cargo from the asteroid to the top of the elevator. The problems include a plane change and orbital synchronization, rendezvous and docking.

That actually sounds like a good overview scenario that fits into the topic too.
I was thinking of lower orbits since there the effects are so much more apparent, but up there we get the same problems as well.

 

[kamaz]

Whatever you do:

Two separate joysticks for controlling the spacecraft, one for translation, the other for rotation. The single most confusing thing in Orbiter is controlling RCS with keyboard.

 

[Linguofreak]

No, you don't store the energy.
Mined stuff goes down, generating energy.
Payload goes up, consuming that energy.
Storing would just waste power.

No need for 100% efficiency either - you can just send more mass down than what you will be lifting.

I don't really get the economic case for downlifting raw materials from asteroid mining to Earth. Earth has plenty of mineral wealth of its own to supply its own manufacturing, and even with a space elevator, it will be cheaper to build products for use in space with materials obtained in space, rather than lifting the raw materials from Earth, or building the product on Earth and shipping it up after manufacturing. Space elevator traffic would probably mostly be passengers and high value/mass items that can only be produced in earth or only in space.

Now that doesn't say that you can't use traffic on the elevator to generate power for listing other traffic. If you forego a traditional counterweight in favor of an extension of the cable well beyond geosynchronous orbit, you can actually use an upbound load destined for solar orbit to lift the next upbound load. (This actually suggests a awesome evil plot for a mad scientist: siphon the earth's oceans off with a hollow, open-ended elevator with one end anchored just above the seabed and the other end hanging halfway to the moon).

EDIT: Oops. That last bit about siphoning won't work, at least not with a simple hollow elevator. The vapor pressure of the water would keep it from getting higher than about 30 feet above the ocean surface.

 

[SolarLiner]

Whatever you do:

Two separate joysticks for controlling the spacecraft, one for translation, the other for rotation. The single most confusing thing in Orbiter is controlling RCS with keyboard.

You push your joystick to go down (or make your nose go down), so you press 8 on the numpad to do that. Easy enough

But I do agree that joysticks are better than keyboard whatever the simulator.

Also, I don't really like the idea of a space elevator as it would require too much "sci-fi magic" going on: building techniques, materials, the acutal "how the are you going to attach that counterweight at the other side?" question, ...
Something more "near-future" would be better IMHO. Or keep things simple: build an object that require specific tasks to be done (monitor Earth's atmosphere, look out to the stars, find other solar systems, etc.).

And maybe a combo of Orbiter/KSP/Space Engine for actual simulation, building fun and "rocket design 101" parts, and beautiful illustrations respectively. Instead of opposing them, I think one should use them to complete one another.

My :2cents: