Switching logic between throttle modes?

Question

At launch, a vehicle like the space shuttle would command its throttle to do a few things:

1. Ramp up to max throttle
2. Hold max throttle
3. Follow a throttle bucket as function of velocity when near max-Q
4. Turn on a 3g controller at 3g to hold, well, 3g.
5. Possibly kill an engine if needed to maintain 3g, as Saturn V did.
6. Ramp down to zero throttle when MECO conditions detected.

How would the throttle transition from one task to the next to the next? Is there a schematic somewhere of the switching logic behind all this? Was it switching logic?

Or would they just multiply the outputs of the ramp, throttle bucket, 3g controller, etc, to obtain the effective throttle at each instant (where the ramp-up output might be 1 after the ramp is complete and the throttle bucket output might be 1 above the max-q region and where the 3g controller might be scaling down the throttle to maintain 3g late in launch and where the ramp-down output might be 1 if MECO not yet occurred...)?

Answer 1

Most of these control systems are written with MathWorks Stateflow. It's a simple way of implementing state machines where you can define behaviors for states and entry/exit conditions for each state. Typically, you will have different trajectory following behavior, throttle control loops, etc for each state.