+- Average IK chain


Hello, I am trying to rig a double jointed knee for a robot model and I have hit a bit of a wall. A friend of mine told me that if I use a ± average on two joints in a knee Maya will take those inputs and average them around a third joint keeping the distance equal. I can then make an IK chain from the foot to the ankle and have a very pretty leg. Now the problem I’m having comes when I get to the ± average. I find it in the hyper shade but when I’m there I don’t know how to apply the joints so it works can anyone help? Also the joint chain looks like
[hip->knee1->knee2->knee3->ankle] And I am trying to get the ± average to work on “Knee1” and “Knee3” so they stay an equal distance from “Knee2.” I’ll be doing the same thing for the arms but I’m considering keeping them in FK.