[0001] US-A-5356500 discloses piezoelectric laminate films using different polymeric laminates. Pelrine et al: Sensors and Actuators A64(1998), 77-85 disclose electrostrictive polymer materials used in solid state actuator technology.
[0002] PVDF is often not suitable for applications requiring strains greater than 4 percent. Shape memory alloys, such as nitinol, are capable of large strains and force outputs. These shape memory alloys have been limited from broad use by unacceptable energy efficiency, poor response time and prohibitive cost.
[0003] In addition to the performance limitations of piezoelectric ceramics and irradiated PVDF, their fabrication often presents a barrier to acceptability. Single crystal piezoelectric ceramics must be grown at high temperatures coupled with a very slow cooling down process. Irradiated PVDF must be exposed to an electron beam for processing. Both these processes are expensive and complex and may limit acceptability of these materials.
[0004] In view of the foregoing, alternative devices that convert from electrical to mechanical energy would be desirable.

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