Controlling Actors Arms

I have a pretty simple task. My project is configured to switch game states when a user presses “E”. When that happens, I want my main actor to stop moving, the mouse to stop controlling the camera, and to start controlling his arm/hand.

The first part works - I can just change the Movement Mode to none on the appropriate play state. I’m not having much luck with the second part. At this point, I don’t care so much about the transition animation - when the user presses “E” I would be happy if the actor’s arm instantly was relocated to be extended directly in front of the actor, about 1 foot in front of his face, palm facing out, fingers in a fist, with the exception of the index finger which will be pointing up.

I would like the mouse movements to move the palm in the corresponding direction while the palm/finger to stay in that plane. So the mouse would move the hand and the shoulder and arm should just kind of “rag doll” to follow the location of the hand while the main body/torso stays in place.

I need to figure out how to:

  1. Detach the camera rotation controls from the mouse when I enter the given play state
  2. Create the initial desired pose of the actor, with arm outstretched 1 foot, etc
  3. Add some sort of smooth acceleration to the hand in the direction of the mouse offset from center. I suppose this scenario makes more sense when I think about it like an analog stick of a game controller, and I would eventually like to add support for this too.

Can anybody help get me on the right path to accomplish this?