I agree with all that cswilson says but I'd suggest using a Slotless Brushless Motor with No shaft Seals. Current = Torque.
https://www.machinedesign.com/technologies/slotless-motors-smooth-way
Mathematically if you input a 1 volt, 1 radian/sec sine wave to the plant input (Vin) and measure the plant output voltage (Vout) (Again a sine wave at 1 radian/sec with an amplitude A) the plant gain is Gain = Vout/Vin = A/1 = A
There is probably a difference between the simulation and the real plant Gain. An Integrating Plant has an Integral Gain which is the plant gain at one radian per second.
If the third outer "Ring" is the transmission Aluminum case the problem might be looked at differently.
1) Interference between a beqring race and the steel ring it's mounted in is well established.
2) When hot the steel ring must not get loose in the Aluminum.
3) When cold the aluminum must...
Skogsgurra,
From "Thrust" in Wikipedia;
1) A rocket is propelled forward by a thrust force equal in magnitude, but opposite in direction, to the time-rate of momentum change of the exhaust gas accelerated from the combustion chamber through the rocket engine nozzle. This is the exhaust...