support layer attached to the electroactive material must be possessed of a surface area greater than the surface area of the mating surface of the electroactive material additionally the support layer must be of sufficient size to extend beyond the boundaries of the surface of the electroactive material attached to it and the entire face of the electroactive material in contact with the support layer must be attached to the support layer fig2 is illustrative of these relationships in the basic embodiment the support layer has an elongated planform when the pre stressing of the electroactive material is done by processing on a mold having a radius of curvature in a single direction only the pre stressed electroactive material is predisposed to increase or decrease this radius of curvature when excited for convenience the direction along this radius of curvature will be referred to as the length of the support layer even though the device may be constructed in such a manner that this dimension is smaller than the dimension of the support layer oriented at 90 degrees to this radius of curvature the support layer is of sufficient dimension to extend a distance beyond the edge of the electroactive material along the length of the device this excess in dimension of the support layer over the pre stressed electroactive material along the length of the device may continue the arc resulting from the forming over a curved mold continue.