these are the instructions i have from my university site, i also have been trying to work from the foundation book 'learning maya 5' (although im using 6.1) each time i can get the skelenton in, add a ik handle, but the knee simply wont bend, the whole leg will rotate no problem, but no bending of the knee, its driving me nutts. any help is welcome.
IK or Inverse Kinematics is one of those things that seems really important and special but actually isn’t that important or that special. It is a useful tool for some things if used properly, though. Go Skeleton > IK Handle Tool and pick the top of the dude’s thigh. Then click the joint in the ankle. Maya automatically sets up an IK chain for the leg. If you move the handle thing about the leg follows, but the foot just sticks straight out of the end of the leg. Select the IKhandle THEN the ankle joint. Go Constraint > Orient. Likely as not the foot twists into a stupid position. Unto to get back to where you were. Select the ankle, zoom in on it and go Display > Component Display > Local Rotation axis. You will need to twiddle this thing around so it lines up with the axis of the handle. On the main menu pick the Select by Component Type button and then turn off all the buttons except the question mark (check out the pic below). Select the Local Axis handle and rotate it straight so it lines up with the world – Y up, Z forward and X left. Click on Select by Object Type again and repeat Display > Component Display > Local Rotation axis to hide the thingummy. Constrain the ankle joint to the handle again and it should stay put. Now your leg IK is the same as in lectures 2 and 3 – move the handle around to move the leg and rotate it to rotate the foot. See, that wasn’t so hard.