Manual Attitude switches

[msligo]

Hello,

I have been working through an Apollo 11 simulation, and I notice that one of the switches that I constantly need to press is the Manual Attitude switches. The problem is, I have no idea what they do!

I've tried looking in AOH Vol 1, but it's very cryptic, and doesn't really help me understand the purpose of the switches. The Manual Attitude switches can be found on Page 61 of this link: https://history.nasa.gov/afj/aoh/aoh-v1-3-cont+disp.pdf

Can someone please tell me what these switches do, and why the settings are called ACCEL CMD, RATE CMD, and MIN IMP?

Many thanks,
msligo

 

[indy91]

As the description of the switches says, they are responsible for the manual attitude control setting. In general (the same applies for thrust vector control) "Rate cmd" means that the attitude rate will be limited automatically, but otherwise any deflection of the joystick rotates the spacecraft. "Accel cmd" has no rate damping and any deflection of the joystick causes an angular acceleration. Minimum impulse mode causes one short burst of thruster firing each time the joystick is deflected. Normally you will be in rate cmd mode.

The long form description can be found in this document: https://history.nasa.gov/afj/aoh/aoh-v1-2-03-scs.pdf Specifically on PDF page 35 and following.

And the NASSP wiki also has a decent explanation: http://nassp.sourceforge.net/wiki/Stabilization_and_Control_System#RHC_Normal

 

[msligo]

Ahh ok, that makes a lot more sense now. I think part of the problem is that I've been using a keyboard instead of a joystick, and I don't think that works very well with RATE CMD, so I wasn't able to work out what it did.

Thanks!