How to connect two engines so that they spin with equal speed and direction?
How to connect two electric motors, so that they rotate with equal speed and in one direction for a string-navivny machine?
To spin at the same speed - you can use synchronous motors or commutator. But in the latter case, devices are needed for automatic speed control and synchronization. How critical is the deviation and how small is the difference?
If the requirements for this are not too stringent, then you can use just the same asynchronous motors, they will rotate at approximately the same speed, if their load is approximately the same