So I am making a puppet big enough for the controller to fit inside, from waist up. The head was easy enough to make, I simply up-scaled my pattern and made it as normal.

For the torso, I have made a chest piece with straps that can attach to the controller chest. The camera will only see the character from straight on, so I don't need to worry about sides/back. However I've come into a bit of a problem with arms. Because the head and torso are separate, not sewn together, I need the arms to be separate too.

I was thinking about making a foam sleeve but it needs to be bendy so I will need joints too. This could be hard because I have limited materials and haven't much experience with foam joints. What I might do is make a foam sleeve from the elbow to shoulders and have a large fleece glove from elbow to wrist/fingers. The character is a human, so I couldn't do a Cookie Monster style furry suit which was a shame. I'm sort of going with the flow at the moment, trying to build something that works. Any have any tips for me?

Its a little hard to explain what I am building, I can post pictures if its easier to understand.

Do you really need the foam? How is the puppet dressed? You said something about fur and not being able to be used, but think of the cloths on the puppet as the fur.  Pictures might help show what you are talking about.

Sketch would be helpful.

if the character is human, why not use an actual human?