A doll contains a flexible sensor which is captured in the doll near a surface thereof and will emit an electrical signal when subjected to bending or pressure to indicate that this part of the doll is being touched or manipulated. The sensor utilizes a film having piezoelectric properties to generate...http://www.google.fr/patents/US4820236?utm_source=gb-gplus-shareBrevet US4820236 - Doll with sensing switch
