Discussion Developing my first satellite

[RisingFury]

What did I tell you about doing research?

 

[Pipcard]

What did I tell you about doing research?

Edit: Okay, fine! I'll research harder!

 

[tl8]

average wattage per cm^2 of a solar panel

This is actually quite simple

Find the power of the sun at the location you want (eg LEO) in w/m^2
Multiply by the efficiency of the panel (eg 5%,10%,20%)

And convert the resultant w/m^2 to the units you want

 

[Pipcard]

1353-1366 W/m² (at least for LEO).
Panels in space are just about 30% efficiency (which will be my satellite's efficiency).

(1360 x 0.3)/10000 =
We're looking at about 0.0408 W per cm² (or 408 W per m²).

Each solar panel face will give me a bit less than 220 W (0.54 m² per face).

Thanks! I am capable of doing research. At least give me hints such as those to help me.

Oh, this ion propulsion thing, it's for something else in the future.

---------- Post added at 08:20 PM ---------- Previous post was at 06:32 PM ----------

modeled some RCS thrusters (that will have hydrazine propellant) and made the solar cells smaller

Will add antennae (and learn how to animate them) right after I learn how to place exhaust in Spacecraft3.

 

[PhantomCruiser]

That's looking pretty good dude!

 

[4throck]

Looks good, detailed and realistic.

 

[Pipcard]

Looks good, detailed and realistic.

Are the thrusters too small to be able to notice that they are not textured?

 

[Scruce]

Are the thrusters too small to be able to notice that they are not textured?

If an object is not textured by a texture or a material, it will not show up in Orbiter. Everything needs to be textured and the bits that aren't worth texturing, you cover in a material.

 

[Pipcard]

If an object is not textured by a texture or a material, it will not show up in Orbiter. Everything needs to be textured and the bits that aren't worth texturing, you cover in a material.

They do have a material.

 

[Scruce]

They do have a material.

You should be fine then. Remember, not every part of your mesh needs a texture, the small and insignificant bits you can just slap a material on.

 

[n122vu]

This is looking really good. Much better than I would be able to produce. Good luck on the sc3 implementation (and eventual DLL version )!

 

[Pipcard]

Just testing how the mesh looks in Orbiter. Added attitude thrust but haven't added visible exhaust yet.

139 kg (dry mass)
5 kg (hydrazine)

The attitude thrusters are loosely based off the MR-50s.

edit: How is ATTITUDE_THRUST calculated? I read the tutorial and looked at the DSCS's config* but I still don't get it. There are 12 thrusters (2 on each side) that are about 0.7 m from the center. And each thruster is supposed to have 22 N thrust. Or can the thrust be lower than that?

*It says "ATTITUDE_THRUST=100 ;8x 50N RCS thruster"

(does it mean the thrusters are simply 2 m from the center of gravity?)

 

[Cras]

very nice. good work!

 

[Eli13]

Looks good so far!
Keep goin'. :thumbup:

 

[PhantomCruiser]

Nice looking rig. Where did you get the gold foil texture?

 

[Pipcard]

Nice looking rig. Where did you get the gold foil texture?

I already said on the previous page; it's from CG Textures, and I colored it with GIMP.

---------- Post added 01-11-12 at 07:04 AM ---------- Previous post was 01-10-12 at 08:55 PM ----------

I just realized yesterday that the DSCS had no "real-life" engines for attitude control; it only had the R-4D as the main engine.

 

[N_Molson]

5 kg (hydrazine)

MMH or UDMH ? :lol:

Don't be afraid to use very small thrusters for such tiny satellites. Those are not starfighters. 1N or less is often enough. Also you might consider placing pairs of them (redundancy)

 

[Pipcard]

Currently adding the exhaust.

Also, the fuel is now 1.1 kg of hydrogen peroxide (H2O2) monopropellant (might change that again; apparently the decomposition of H2O2 does not produce flame). The attitude thrust parameter is 0.4 N.
(there will be no pairs of thrusters. I want 12, not 24)

Is the X-axis on Wings3D reversed in Orbiter? I think so.

edit: Okay, just finished all 12 thrusters. Now it's time to move on to animations.

(paused during a killrot)

Just to make a note here: the part with the two rectangles and a circle is the front.

---------- Post added 01-12-12 at 12:53 PM ---------- Previous post was 01-11-12 at 06:25 PM ----------

edit: Okay, I'm still looking for an attitude thruster propellant. (non-toxic, continuous thrust, produces a flame)

 

[Pipcard]

I'm stuck at the animations part. My 4 antennae are arranged in a diagonal configuration like this:
\ /
/ \
(or a + rotated 45 degrees)

I'm not sure how to rotate diagonally, and when I add a second anim_comp, for another antenna group and rotation point, the animation becomes wonky (as if it were combining the rotations of the two groups).

 

[Keatah]

First satellite, eh? Not too shabby!