If we provide actuator to the model then it works on which phase of gait cycle?

[RAHUL GHARATE]

If we provide an actuator to the model and path of the actuator is acts along the path between the femur and foot segment. Then actuator affects on which phase of the gait cycle? i.e at stance phase or swing phase or at initial contact or at plantar flexion or at dorsiflexion? How we can decide it?
If I want it's effect in a particular phase then how I proceed further?