Request Artemis landers

[gattispilot]

Thanks. So far it is working. So now I need to figure out how to stop the main engine from always firing. Also a weird thing. using the / key can't switch rcs rot/trans. But can from the hud?

 

[francisdrake]

Very good, that the basic functions seem to work now.

On the keys: I think, you may accidently intercept some (all?) keystrokes in clbkConsumeBufferedKey().
Also I could not activate the MFDs. Maybe first use the glass cockpit only. If that works, then activate the functions of the virtual cockpit.

And, I wish you a Happy New Year 2024!

 

[gattispilot]

Happy new year. I got a lots of work to do on the interior

 

[gattispilot]

Thanks. So now one things. Trying to get the main to fire for a bit and cut off. If I set main thrust to fire when separate. It continues to fire even though I don't want it to.Still get that moon bounce issue

Confused. For the main lander vessel is this correct. forward is along the Y axis and up/down is along the Z axis? But the ascent forward is along the Z and up/down along the Y

 

[francisdrake]

Yes, the picture shows the tailsitter orientation, This is the ascent stage after the transformation, with +z in forward direction.

 

[gattispilot]

So on the main vessel it is a hover vessel aka lander. Which axis is forward and up/down

 

[francisdrake]

The lander is a hover vessel:
+y = forward;
+ z = upward;

If you like, you could skip transformation for now, and keep the ascent vessel also as a forward looking vessel.
The ascent is anyhow mainly controlled by instruments (Orbit MFD and AlignOrbit MFD), looking out of the window is not essential.

 

[gattispilot]

Thanks. The ascent vessel is good. But trying to figure out the RCS for the main vessel hover vessel. So when you want to move forward you along the y axis (0,1,0), right?
and to move up (0,0,1), right?

 

[barrygolden]

you might need to get the aux trusters to fire as well

 

[gattispilot]

Sure. I just need to get the rcs for the main vessel. The ascent is 90 degrees offset of the main. So in the ascent vessel separated. When you press the rcs to go forward it follows the Z axis. But if sitting in the main vessel (ascent and descent) when you press rcs to go forward you follow the Y axis, right

 

[francisdrake]

Yes thats right. I make two different sets of thrusters for the descent and ascent stage.
For the descent stage (hover vessel), the main force points up into +Y, and the RCS thrusters are grouped accordingly.
Up is (0, 1, 0).

For the ascent stage (tailsitter) the main thruster points upward, now to +Z, and has a new set of RCS thrusters.
Up is (0, 0, 1).

Orbiter uses a left-handed coordinate system, I type with the right hand and use my left hand to visualize the vessels' main axes.

 

[gattispilot]

Thanks. That's what I thought.

Now I might need to set a timer to start when separeated and fire main thruster and then cut off after a time. Then as needed fire it. Right now it is all or nothing.

 

[francisdrake]

When you start the engine at the end of the transformation event, it will fire and you can kill it later with the 'engine out' key.
It will not re-fire automatically.

void LML::blowDesc() { .... strcpy(name, GetName()); strcat(name, "-DS"); oapiCreateVessel(name, "LMLander/LMDesc", vs); SetConfig4_asc(); SetThrusterGroupLevel(THGROUP_MAIN, 1); // ActivateNavmode (NAVMODE_KILLROT); }

 

[gattispilot]

Which key is "engine Out" I pressed "-" and it stopped but then restarted

"*" is engine kill

 

[francisdrake]

I think, this the right key.

When it re-starts, check the PreStep loop. Maybe there is accidently a SetThruster command.

 

[gattispilot]

Thanks.
So now got an issue. It seems to be related to the thrusters.
I added the aux thrusters for the ascent thrusters.

THRUSTER_HANDLE th_descent[10], th_rcs[70], th_group[60], th_aux[8];

Now when I apply hover it CTD.
void LML::SetThrusters1_Orbit() { ClearThrusterDefinitions(); ClearPropellantResources(); //descent stage // Define propellant resources ph_RM = CreatePropellantResource(LEM_DescentFUEL); // Descent stage propellant tank SURFHANDLE tex_main = oapiRegisterExhaustTexture("Exhaust2"); // Define Thrusters: Main Engines SetDefaultPropellantResource(ph_RM);// Set descent tanks as default propellant resource th_descent[0] = CreateThruster(_V(1.2, -10, 1.2), _V(0, 1, 0), LEM_DescentTHRUST / 4, ph_RM, LEM_DescentISP); // Orbiral stage engine SetThrusterResource(th_descent[0], ph_RM); // Enable descent engine th_descent[1] = CreateThruster(_V(-1.2, -10, 1.2), _V(0, 1, 0), LEM_DescentTHRUST / 4, ph_RM, LEM_DescentISP); // Orbiral stage engine SetThrusterResource(th_descent[1], ph_RM); // Enable descent engine th_descent[2] = CreateThruster(_V(1.2, -10, -1.2), _V(0, 1, 0), LEM_DescentTHRUST / 4, ph_RM, LEM_DescentISP); // Orbiral stage engine SetThrusterResource(th_descent[2], ph_RM); // Enable descent engine th_descent[3] = CreateThruster(_V(-1.2, -10, -1.2), _V(0, 1, 0), LEM_DescentTHRUST / 4, ph_RM, LEM_DescentISP); // Orbiral stage engine SetThrusterResource(th_descent[3], ph_RM); // Enable descent engine // th_descent[4] = CreateThruster(_V(0, -2.8, 0), _V(0, 1, 0), LEM_visTHRUST, ph_hover, LEM_visISP); // vishover // SetThrusterResource(th_descent[4], ph_hover); th_group[0] = th_descent[0]; th_group[1] = th_descent[1]; th_group[2] = th_descent[2]; th_group[3] = th_descent[3]; //th_group[4] = th_descent[4]; CreateThrusterGroup(th_group, 4, THGROUP_HOVER); // Render thruster exhaust // for (int i = 0; i < 4; i++) AddExhaust(th_descent[i], 4.0, 0.8, 1.0, tex_main); // Descent engine exhaust [length, width, offset] AddExhaust(th_descent[0], 4.0, 0.8, 1.0, tex_main); // Descent engine exhaust [length, width, offset] AddExhaust(th_descent[1], 4.0, 0.8, 1.0, tex_main); AddExhaust(th_descent[2], 4.0, 0.8, 1.0, tex_main); AddExhaust(th_descent[3], 4.0, 0.8, 1.0, tex_main);

 

[gattispilot]

Here is a test version. Still lots to do. I think the thrust, ISP, fuel may need to be adjusted. CTRL J separated the modules. G animates the Gear.

 

[francisdrake]

Nice one!
Two observations:

The scenario LMLANDERDOCK is dependent on another addon, Artemis2.
Could you provide a download-link for that, or make the lander just free-flying, without any other addon?

The descent stage needs much more fuel. I made a Lunar orbit scenario, but it ran out of fuel quickly.
Could you maybe publish the figures of dry mass and wet mass, both for the descent and ascent stages?

 

[gattispilot]

Here is the Artemis2:

OHM - Space Launch System for Orbiter 2016 0.1.2

I left off the Aux thrusters. Now they are added. probably no more updates until we see the real inside. The only update that I need help on is the 2 joystick setup

www.orbiter-forum.com

Lockheed Martin Lunar Lander - Wikipedia

en.wikipedia.org

Lockheed Martin proposes a mega-lunar lander: 62 tons and an elevator

"What we chose to do is jump to the end game."

arstechnica.com

I think the original design was a single stage?

 

[francisdrake]

Yes, the Lockheed concept was a single-stage lander. It was derived from the Mars lander concept MADV, subtracting all the aerodynamics.
It used LH2 as fuel in the voluptuous main tank.

For the masses, you could try theses figures:
Ascent stage
Dry 12 ton
Fuel 7 ton @ 3800 m/s ISP (storable propellant)

Descent stage
Dry 26 ton + 19 ton from above = 45 ton
Fuel 23 ton @ 4500 m/s (LH2 + LOX)
The mass ratios give a dV of 1.7 to1.8 km/s, which is the minimum to and from Low Lunar orbit to the surface.

Thrust = 4 x RL-10 @ 110 kN = 440 kN
This gives a full-tank acceleration of a = F/m = 6.4 m/s²