Dynamic Simulation Alternating Torque?

[Anonymous]

Hi,

I'm trying to simulate an escapement for a watch and have the Roller Lock push into the Pallet. However, when I try to simulate the rotation of the Roller, I run into a theoretical issue.. I can't seem to see how to implement an oscillatory motion that is able to drive the motion of other components without losing power, as I would need an alternating torque. 

I have already tried to simulate the motion by placing a constant force on the Roller Lock in the direction that would simulate "gravity" on a pendulum since this creates oscillatory motion; however, I run into the issue that the motion quickly stops and finds it's equilibrium point, halting the oscillation after a one or two oscillations, and quickly losing power. This makes sense, since the oscillation motion needs to drive the motion of the Pallet, but I would like to have a simulation which allows me to keep an alternating rotation going in order to test other aspects of it.. Hence, having an "alternating torque" should theoretically alleviate this issue, but I couldn't find any way to implement it..

As the above seemed to work to a point, I tried to stick with it and reduce friction and other constants, since I thought that a no friction/lossless element would behave the same as if there was a torque on the Roller; however, I can't seem to get it right, and it still quickly loses power. 

Has anyone encountered this before? Any tricks? Is this possible with other programs in the Design and Manufacturing Suite? Or am I missing something fundamental? I'm not quite as well versed in ME as I am a EE myself, so thanks in advance for your help.