Shape Control Of Piezoelectric Curved Beam And Calculation Of Shear Coefficient Of Curved Beam

With the development of modern science technology and high precision instrument, the requirement of materials, especially intelligent materials, is becoming more and more high. The intelligent material is a kind of material that combines sensing, controlling and actuating. It not only can perceive the external information, but also can deal with the problems encountered. At present, there are many kinds of intelligent materials, and a kind of widely used piezoelectric material in this paper is studied. Piezoelectric smart material owns the quick response ability and good operability, it can be applied in many different fields such as aerospace, ship, missile, automobile, medical machinery, geological exploration and so on. In addition, the straight beam cannot meet the accuracy requirements of the modern design in dams, bridges, and other complex architectures. Therefore the research of the curved beam is an important work. In this paper, the built-up structures of piezoelectric curved beam and curved shell are constructed and the numerical analysis of the finite element are studied and analyzed.Firstly, this paper introduces the characteristics and applications of piezoelectric materials. What's more, the research progress of shape control of piezoelectric structures and shear coefficient of the beam is reviewed.Secondly, since the application of curved beam is common, we have a higher requirement of the accuracy for the curved beam structure. However, the shear coefficient traditionally defined as 1.2 was used to calculate and analysis of curved beam structure. In this paper, it is concluded that there is a certain amount of error between the calculation results of the shear coefficient 1.2 and the actual results through numerical comparisons. Based on the research of the factors affecting the shear coefficient of curved beams, this paper derives a new method to calculate the shear coefficient of the curved beam. The calculation results are compared with the use solid elements of ANSYS, which shows the computing method of the shear coefficient presented in this paper are more accurate.Thirdly, based on the finite element model of the curved beam and curved shell and the constitutive equation of piezoelectric material, this paper constructs the built-up structures including 3 nodes of curved beam element and 9 nodes of curved shell element. The connection of the piezoelectric curved beam element and the curved shell element is realized and the integrated global stiffness is obtained. The computing accuracy of curved beam element and shell element is verified by numerical examples and the effectiveness of the calculation results of the connection model and piezoelectric curved beams is discussed. At the same time, the calculation results of the proposed method in this paper are compared with the shear coefficient of 1.2, which further proves the validity of calculation method.Finally, the static shape control of the built-up structure of piezoelectric curved beams and curved shells is realized. The least square method is utilized to find the optimal voltage distribution in the structure. The curves of the deformation and the percentage of error are given. The static shape control is carried out on the bending and torsion deformation of the stiffened flat plate and curved plate, and numerical results demonstrate the accuracy of the model and the applicability of the theory presented in this paper.