I could be wrong, but I do not think that shielding is the answer to your potential issue.
I would suggest electrically conductive connection between all the foam parts and then connect that "circuit'" to the arduino's ground.
I could be wrong, but I do not think that shielding is the answer to your potential issue.
I would suggest electrically conductive connection between all the foam parts and then connect that "circuit'" to the arduino's ground.