Adaptive antenna shape control using piezoelectric actuators

This paper presents improved techniques for the shape control of composite material plates using piezoelectric actuators. The application of this work is for the shape control of spacecraft antenna to correct surface errors introduced by manufacturing, in-orbit thermal distortion, and moisture. A finite element model has been developed for a composite plate with distributed piezoelectric actuators and sensors. To improve the accuracy of the prediction of plate deformation, a simple higher-order deformation theory is used. The electric potential is treated as a generalized coordinate, allowing it to vary over the element. The applied voltages to the actuators are optimized to minimize the error between the desired shape and the deformed shape. Based on these techniques, two computer programs were developed on finite element modeling and optimization. The analytical results demonstrate the use of piezo-electric actuators for the active shape control of spacecraft antennas.