I have drive and driven gears mounted on the drive and driven shafts respectively. Torque and speed are applied to the drive shaft. When my dynamic simulation starts, some random force is generated but when it reaches a steady state, the transmitted force is zero.
Spec:
1- Two spur gears
2- Method: Detailed
3- Contact setting as default (friction, stiffness, and damping are considered)
4- The connection type for both gears is fixed to the shaft.
5- The drive shaft has a revolute joint and the drive shaft (with a larger gear) is supported with two bearings.
See the following picture and please let me know what the issue is.
If you have no friction in the joints of the driven shaft and no other resisting force, then the effort to keep the driven side at constant velocity is zero. No work needed, hence no force.
It will not matter if you add friction to the drive shaft.
Regarding the bearings on the driven shaft:
The bearing element does not have any friction around the spin axis by default. You will have to define this yourself.
My first comment still stands; if you don't have any resistance on the driven shaft, the shaft will just keep spinning by itself, and will need no extra torque after the initial spin-up.