m4v

[1.2] RCS Build Aid v0.9.1

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How come this isn't affected by tweaking the RCS thrust limiter? No matter what I set it at, if I have two RCS blocks putting out 1Kn each the window always reads 2Kn.

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How come this isn't affected by tweaking the RCS thrust limiter? No matter what I set it at, if I have two RCS blocks putting out 1Kn each the window always reads 2Kn.

RCS's thrust isn't tweakable, what are you talking about. If you're using TweakableEverything mod or similar, then state it. If is TweakableEverything then that's an issue with that mod and not RCSBuildAid.

Edited by m4v

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Apparently, even though I thought I removed TweakableEverything, it was still in another install folder that I copied over, so I was using it without realizing it hence not mentioning it.

I'll see if the TE modder can fix whatever is causing RCS Build Aid not to register the change in thrust. This would make things a lot easier to balance out an uneven craft that doesn't have a way to change its CoM (like pumping fuel around)

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Ok so I am building a space shuttle and have been trying to use it with this mod and failing miserably.

How do we use the rcs aid to build a shuttle? Do we WANT torque? Do we want the green arrow point straight up because I can NEVER get it to do that. I'm just frustrated and at a loss. I've adjusted trim, I've rebalanced fuel, I've done everything I can to make this stupid thing fly in RSS and RSO but it 1) Always wants to do a front flip even though NO torque is showing in the VAB 2) I can't control the craft other than go straight up.

I've attached rxn wheels to my shuttle etc. It's starting to really irk me.

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Ok so I am building a space shuttle and have been trying to use it with this mod and failing miserably.

How do we use the rcs aid to build a shuttle? Do we WANT torque? Do we want the green arrow point straight up because I can NEVER get it to do that. I'm just frustrated and at a loss. I've adjusted trim, I've rebalanced fuel, I've done everything I can to make this stupid thing fly in RSS and RSO but it 1) Always wants to do a front flip even though NO torque is showing in the VAB 2) I can't control the craft other than go straight up.

I've attached rxn wheels to my shuttle etc. It's starting to really irk me.

A picture of the craft would really help here. I have a SSTO spaceplane that I have RCS Balanced quite well and I haven't had any issues with it.

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You should angle your main engines on your shuttle to fire through the center of mass. (Make sure SRBs are attached) and then you should have a second set of non-angled engines for orbital maneuvers.

Check out this mod (If you don't have it already)

Edited by Taki117
Added link.

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I really don't know how to build a shuttle type rocket. You don't want to have much torque (as in any rocket) but getting the thrust direction to point straight up might not be feasible. The biggest problem would be to keep it balanced as it burns fuel, since the CoM will start shifting to where the DCoM is and then if it isn't balanced it will start flipping.

I believe that most of the shuttles out here use some automatic balance mod for keep everything straight during flight but I could be wrong.

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Unless you use dtobi's Shuttle Engines mod you're going to have trouble, because the real shuttle engines had ~10 degrees of gimbal, while most KSP engines have 1. That's simply not enough to keep it targeting the CoM as fuel mass changes balance.

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Yeah I'm already using that mod... along with real engines, engine ignitor and rss.

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Can someone explain what each arrow color represent (in the build aid)? I've looked at the tutorial pics on the first page but I'm not very clear what they all mean.

Green = direction of thrust

Red arrow = ?

Red ball = DCoM (dry center of mass)

Red spinny thing = torque (which I asssume represents tendency for a craft to spin due to its thrust vector?)

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Can someone explain what each arrow color represent (in the build aid)? I've looked at the tutorial pics on the first page but I'm not very clear what they all mean.

Green = direction of thrust

Red arrow = ?

Red ball = DCoM (dry center of mass)

Red spinny thing = torque (which I asssume represents tendency for a craft to spin due to its thrust vector?)

Red arrow is torque, the red circular arrow represents the angular acceleration, but you can call it the tendency of the craft to spin.

You might have torque (red arrow is visible) but not a significant angular acceleration (no circular arrow is shown), so reducing torque to zero might not be necessary. Unless you want a rocket that flies straight without SAS and without input.

Edited by m4v

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Right well... I get my torque down to 0 in the VAB, launch my craft, all of a sudden the ship starts torquing like a nutt job. I revert back to VAB, torque is now 800 kN.

The problem isn't me, its the false information that RCS build aid is giving me during my design process.

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Right.

Did you check the balance in both the CoM and DCoM markers? And as other pointed, it might not possible to do what you want with engines without enough gimbal.

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The funny thing is about the real space shuttle. When it takes off the shuttles boosters are not at 100% throttle. It isn't till a few seconds before the SRBs are separated that they go full throttle on the shuttle engines. You may want to test launching at different throttle settings to see if it fixes your launch control issues.

I never had much luck with a piggy back shuttle launch like the real shuttle but I only messed with the concept for about a day then I moved on.

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The funny thing is about the real space shuttle. When it takes off the shuttles boosters are not at 100% throttle. It isn't till a few seconds before the SRBs are separated that they go full throttle on the shuttle engines. You may want to test launching at different throttle settings to see if it fixes your launch control issues.

I never had much luck with a piggy back shuttle launch like the real shuttle but I only messed with the concept for about a day then I moved on.

I asked myself that question as well and tested different throttle settings to see if it would work. The problem is the rcs build aid give me wrong information on thrust torque. It isnt until I reach the launch pad that the stupid thing corrects itself.

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I asked myself that question as well and tested different throttle settings to see if it would work. The problem is the rcs build aid give me wrong information on thrust torque. It isnt until I reach the launch pad that the stupid thing corrects itself.

Again, check both the CoM and DCoM markers, click in the "Reference" button, you're probably balancing for one marker but not the other, and as you should be aware, the center of mass of your vessel will shift from the CoM towards the DCoM.

If you still think that is giving false information then show me some screenshots so I can try to figure what is going on.

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I asked myself that question as well and tested different throttle settings to see if it would work. The problem is the rcs build aid give me wrong information on thrust torque. It isnt until I reach the launch pad that the stupid thing corrects itself.

Make sure you don't have any of your fuels/monopropellant/whatnot checked (eg. ignored) in the RCS options box in the VAB. if you do, you might be getting incorrect CoM/DCoM stats. (I use RealFuels in RSS so I am acutely aware of what happens when RCSBA is ignoring something, like Hydrazine or LiquidH2.)

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Is there any way to make RCS BuildAid focus on a single stage? I'm building a 2-part lunar lander, and for the landing stage the dry CoM includes the ascent stage, so I have no idea where the dry CoM would be with the ascent stage's tanks still full like they will be during landing.

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I'll see if the TE modder can fix whatever is causing RCS Build Aid not to register the change in thrust. This would make things a lot easier to balance out an uneven craft that doesn't have a way to change its CoM (like pumping fuel around)

This past week TweakableEverything made the fix to allow RCS Build Aid to recognize the change in RCS thrust. It will soon be able to allow finer tweak values as well (down to 1%). Great news for taking care of asymmetric thrust without having to always move RCS blocks around!

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Is there any way to make RCS BuildAid focus on a single stage? I'm building a 2-part lunar lander, and for the landing stage the dry CoM includes the ascent stage, so I have no idea where the dry CoM would be with the ascent stage's tanks still full like they will be during landing.

Not possible, RCSBuildAid isn't stage aware and I'm not sure how to do that. You will have to remove the parts that you don't want or play with the fuel sliders like NathanKell pointed.

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