Connect two or more objects

Simply put I want to make a simple stick man. I already placed everywhere where I want it to be by default (you can check the image below). What I want to do is attach all parts together (every part is different color) so I can animate it easier. So basically what I want is that upper arm rotates around torso (like a normal shoulder would) but it will drag the lower arm with it and preserve angle between then, lower arm rotation would be anchored at it’s joint etc. I tried a few joints but I can’t figure out how to properly make it. If you need any additional information, or you don’t understand what I want to achieve please ask for additional explanation.

Image (White dots would be the joints) :
alt text

So I managed to achieve this by making a lot of custom pivot points and connect them via parent-child “method” which seems to work decent. Only had some problem with animation working with absolute position and not relative (should be easily fixable).