Prograde angles wrong below 70,000M on Kerbin.

[unixunion]

Prograde angles wrong below 70,000M on Kerbin.

[erendrake]

If i remember correctly the prograde vector is relative to your orbit and the steering vector is relative to the surface. It might account for the difference, ill check it out and maybe expose the surface vector too.

[unixunion]

Ok, It could be that, however I am trying to follow the navball prograde in my code. Ill check steering out. But when I launch and use SAS to head as straight up as possible ( navball confirms that ), I get a reading of prograde:yaw: 83.2. should this not be closer to 180?

/K

[jcramb]

I am having a big problem with this also. Trying to implement a real gravity turn as opposed to just "turn at 10km etc.", I need to lock the roll and yaw, but allow pitch to change naturally under gravity and kOS is failing pretty hard. The steering variable doesn't allow me to lock roll/yaw while keeping pitch unlocked... and so I try to lock it to the prograde vector, but the one displayed by the navball (which is correct) is not even close to what is displayed by kOS.

Hope this can be fixed soon, because kOS is kickass and I would like my launch script to be able to do proper gravity turns.

Is there ever a reason why the prograde vector in kOS should not be the same as the navball?

[erendrake]

Im pretty sure that locking prograde locks to orbital prograde, and you are trying to get surface prograde?

[jcramb]

That would explain it :) Is there anyway I can access my surface prograde? I am pretty keen to be able to lock/unlock on a member basis too, how difficult do you think that would be to implement. If it is simple enough to do I will try to code it up.

[bshepherdson]

You can't lock on a member basis, but you can write expressions for the
components instead of single values. Then the values will be updated every
tick, and your rocket will follow a smooth curve.

On Saturday, February 8, 2014 3:19:23 AM, John Cramb <
[email protected]> wrote:

That would explain it :) Is there anyway I can access my surface prograde?
I am pretty keen to be able to lock/unlock on a member basis too, how
difficult do you think that would be to implement. If it is simple enough
to do I will try to code it up.

Reply to this email directly or view it on GitHubhttps://github.com//issues/292#issuecomment-34538473
.

[dcrockwell]

Accessing surface prograde as a rotation rather than a vector is essential for allowing the proper euler rotation of the craft while following surface prograde on the navbal..

Without it, we're forced to use LOCK STEERING TO R(0,0,0) + VELOCITY:SURFACE which returns a vector that you cannot rotate.

[erendrake]

just FYI, this is the repo for the old version from 2013. if we dont have this issue in the new repo https://github.com/KSP-KOS/KOS i would appreicate you adding it so we can discuss it

[dcrockwell]

Oh Sorry! Thank you very much Eren!