Hello everyone,
I’m trying to create a 2d game for mobile, but I have a problem. I have a character with “2d rigid body” and a “2d box collider.” I want arms of the character to move independently when the character jumps or moves. So I separate the arms from the body, creating 3 separated sprite. I inserted the sprite of the arms as children of the main sprite (body) and added to each of it a “2d rigid body” and a “2d box collider,” just as the body of the character. Obviously starting the scene his arms fall to the ground. How can I do in order to “nail” them to the body? The effect I want is that the arms can swing according to physics, during the movements of the character.
thanks everyone for the help and sorry for English not entirely correct, but it is not my native language.
I also have the same problem and I would be interested to know the solution 
http://unity3d.com/learn/tutorials/modules/beginner/physics/joints
I believe this is what you’re looking for. The example is in 3D, but there’s 2D functionality as well.
This is exactly what I was looking for. Thank you very much!