I'm having trouble getting an IK rig to work how I want it to. My goal is to have a hammer in my characters arm that I can move and rotate have the arm and hand rotate properly like it would for a real person, where the forearm rotates forward and backward mostly with the wrist being pretty much still and maybe a bit of upper-arm action if the forearm goes above a certain angle forward/backward.
The position part of the ik is pretty good, but I'm struggling with the rotation. I've set up my hammer model with a child bone in it going from the handle near the point where it intersects with the hand to the head of the hammer. The IK of my hand is set to the 'hammer bone' with location and rotation applied and a chain of 4 (shoulder is the end). It sort of works, but is un-natural in that the wrist rotates instead of the arm. I'm sure it is just my fault at not being an expert. I've tried different rotation constraints, but can't seem to figure out the one that works/the right way to do it.
I've found some good tutorials on IK, but I couldn't find any sort of forum posts or tutorials that cover how to do it with a hammer or bat or similar tool where the tool drives the rig. I would really appreciate it if someone could direct me on this.