automatically changing a load during a dynamic load step

[GeorgeEllwood]

Hello,
I'm trying to model the rotation of a turbine blade. I'd like to apply a force to the blade which starts it to rotate. After it's moving I'd then like to apply a counter moment to keep the blade rotating at a constant velocity.
Any ideas how I can get abaqus to monitor the acceleration/velocity and then apply a counter moment to stop the blade from accelerating?
Many thanks
George