Search results

I think a new release is a good idea. I'm busy for the next 2 weeks or so, so I won't be able to do any work (I'll keep an eye on the forums in case anyone has questions). Regarding the new MPS stuff: does this require scenario changes? If we have to update scenarios to handle the new MPS, we...

Checked in the fixed code.

I think I've finally found the problem, actually. There are a couple of sign errors for the yaw gimbal, both in CalcSSMEThrustAngles and in correcting for the null position offsets. I can check the code in. The other problem I'm encountering is that shutting an engine down early during second...

Yes (MM 202), sort of (the ORBIT TGT display, which requires the target vessel to be defined in the scenario), and yes (although the deorbit burn has to be targeted manually).

I found one problem; in CalcSSMEThrustAngles, you're calculating the cosine of an angle in degrees - it needs to be converted to radians first. After fixing this, shutting off the left engine causes the stack to spin out of control; shutting off the right engine works fine.

That sound right. Orbitersim ignores that mass of attached vessels; the UpdateMass function adds the mass of all the attached vessels to the shuttle mass. The other problem you might have is with the CG updating code. Currently, the CG updating code estimates the ET CG based on the amount of...

Can you post/commit the code you have? As far as I can tell, what you've done looks fine. I think the existing gimbal angle calculations are slightly off (using atan/atan2 instead of asin is probably correct), but the angles are small enough that this shouldn't have a big impact).

The throttle bucket is defined in the mission file using the "ThrottleDown" and "ThrottleUp" values (both are velocities in fps). At the moment, the SSMEs throttle down to 72%, which is hardcoded.

The values you're getting from Orbitersim values are RYP angles (i.e. rotation occurs around the roll axis first, then yaw, then pitch). If that's the behaviour you want, then everything is fine. In http://www.orbiter-forum.com/showthread.php?p=475661&postcount=30 you seem to want PYR angles...

I figured out what's happening; p = atan2(mRot.m23, mRot.m33); y = asin(mRot.m13); r = atan2(mRot.m12, mRot.m11); gives rotations in RYP order, not PYR. Sorry for messing things up. You should be using P = -atan2(mRot.m23, mRot.m33); Y = -asin(mRot.m13); R = -atan2(mRot.m12, mRot.m11)...

When you're in a prograde attitude, what is the calculated attitude? Also does it handle single-axis rotations (just pitch, yaw or roll) correctly?

You might want to use p = atan2(mRot.m23, mRot.m33); y = asin(mRot.m13); R = atan2(mRot.m12, mRot.m11); instead (I think this is what you were using in one of the previous posts). This version is what is used by Orbitersim to convert the rotation matrix to Euler angles (the...

There's one minor error in the PYR code: it should be Y = asin (vz.x); (no minus sign) What are you trying to measure? Your code looks fine, but I suspect the reference frame might not be what you want. At the moment, your reference frame is the Orbitersim prograde attitude, and you're...

B^T is the matrix transpose (https://en.wikipedia.org/wiki/Transpose).

Here's how it's done in SSU: A = target attitude (rotation matrix in global frame) B = current attitude (rotation matrix in global frame) C = B^TA PYR angles = ConvertRotationMatrixToPYR(C) The PYR angles here represent the rotation angles from the current attitude to the target attitude. The...

If I understand you correctly, you want to find the rotation matrix R so that A = BR (i.e. R is the rotation from frame B (the ref frame) to frame A): A = B B^{-1}A = B^{-1}BR B^{-1}A = R Since B^{-1} = B^T , this means that R = B^T A. Now all you have to do is find the PYR angles...

Checked in a fix for the vent code.

I'm not sure what's happening here; I tried the vent code using the current pad mesh and everything works (although the vent positions are slightly off). Can you check the code in so I can take a look? Use a LC-39 branch if the new pad isn't ready for the main branch.

The line above should be vtx_goxvent[2] = FSS_POS_GOXVENTL + FSS_POS_GOXVENTDIR;

Done.