  We consider possibility of embedding large sheets of polymer piezoelectrics
in clothing for sensing and energy harvesting for wearable electronic
applications. Power is generated by the crumpling of clothes due to human body
movements. From the mechanics of a gently crumpled foil we develop theoretical
models and scaling laws for the open circuit voltage and short circuit current
and verify via experiments. It is concluded that stretching is the dominant
charge generation mechanism with the open circuit voltage and short circuit
current scaling as $l^{i}$ and $l^{i-1}(\mbox{d}l/\mbox{d}t)$, respectively
with $1\leq i\leq 4/3$ and $l$ the height of the crumple cone.
