>>12343209Here's another controller, this time from the SSME. I also haven't a clue about the computer, honestly I'd imagine that's probably one of the most ITER parts of the rocket, since I'd imagine it's probably one of the hardest things to design and integrate considering how important it is.
If sensors do penetrate the wall of the engine I'd assume that they do so in the same way spark igniters do, and that they are likely either almost completely flat or placed with symmetry to prevent them from causing unpredictable flow instability.
Other sensors might simply be affixed to the outer wall of the engine, like temperature and vibration sensors, the gimbal controls don't have to perforate the engine they just attach to the armature that actuates it. Here's how a pintle injector works
https://www.youtube.com/watch?v=l8xsqomDQWIAs you can see there's no need to actively move it with an electric motor, it's opened by a certain range of pressure in the line. In a rocket injector you would set the injectors to the range you determine to be necessary for your engine between it's minimum and maximum operating powers and then a powered valve further up the line away from the engine will regulate liquid flow to the injector, no need for controls to ever enter the powerhead itself to do that. That regulator further up the line is what's actually throttling your engine, the valve simply determines the range of throttling.
