Development of new active composites using conventional structural materials are described in this paper. An active CFRP/Al laminate was proposed and developed, which became flat when it was kept at its hot pressing temperature 393K by electric resistance heating of the carbon fiber in the CFRP layer, and its curvature increased when it was air-cooled. The mechanism of its actuation is fundamentally the same as that of bimetal, but its major advantage is its directional actuation due to directionality of the reinforcement fiber and its anisotropy of CTE. FRM based active material was also developed. SiC fiber reinforced aluminum composite was laminated with unreinforced aluminum plate by the interphase forming/bonding method using copper insert foil. Curvature of the material monotonically changed as a function of temperature. It was also clarified that the copper concentrated around the SiC fiber which was introduced by the interphase forming/bonding method contributed to curvature increase of the actuator. In order to detect its deformation, pre-notched optical fiber was embedded in the active material and successfully broken in it to form an optical loss type sensor. Using this sensor, a simple relation between curvature change and change of optical loss to be used for its shape control was successfully obtained.
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