/3/ - 3DCG

So Ive had this problem for a long time and the way ive always gone about addressing it is to just tailor my animations to avoid it.

See how the shoulder collapses when it rotates on it's aim access? Whats the best method for avoiding this? Other than corrective blend shapes.

On the forearm I have 2 bones in line with each other. On has its aim axis locked and bends for the elbow, the other has every axis but the aim axis locked to it gives the twist the radius would give in real life. That works great for that but when I tried the same trick in the upper arm it just didn't work. The extra bone would not twist to accommodate the IK.