| The changes in shapes of fiber-reinforced composite beams, plates and shells affected by embedded piezoelectric actuators were investigated. Two analytical methods were developed. The first can be used to calculate the changes in shapes for specified applied voltages to the actuators. The second to determine the voltages needed to achieve a specified shape. Both methods are formulated on the basis of mathematical models using two-dimensional, linear, shallow shell theory including transverse shear effects which are important in the case of sandwich construction. The solution technique used is the Ritz method. Two computationally efficient, user-friendly computer codes were written which are suitable for performing the numerical calculations. The first code, designated as SHAPE1, provides the change in shape for specified applied voltages. The second, designated as SHAPE2, gives the voltages needed to achieve specified changes in shape. The first code can be used in the design of the actuator system to determine the configuration most suitable for the given application. The second code can provide, during actual service, the voltages needed to achieve the desired shape changes.; To validate the methods and the computer codes, results generated by the codes were compared to existing analytical and experimental results and to test data obtained during the course of the present investigation. The predictions provided by the SHAPE1 and SHAPE2 codes were in excellent agreement with the results of the other analyses and data. |
