Forced motion is not following my command
 

Hey guys. I am simulating a three-blade vertical axis turbine and it is a forced motion simulation. I input the same rotation motion equations for the 3 blades separately, but the results of torque I got are not right. These results should be in the same pattern with a 120deg delay but they are not. I captured the motion animations and found that the blades are actually not moving as I commanded. What I am really confused is that since it is a forced motion simulation, the blades should moving as the function I input. (I have monitored the function as well and it is absolutely right.) Why does this happen and what is the solution of this situation?