Shape Analysis And Surface Active Adjustment Of Large Flexible Smart Cable Network Structure

Finite element modeling of smart cable network structure, pre-tension optimizationdesign of cables and surface active adjustment have been studied in this paper. The mainresearch works are as follows:Firstly, finite element equations of the flexible cable element are derived from aview of geometric nonlinearities. According to piezoelectric equations of the actuatorand nonlinear finite element equations of the flexible cable, the coupled mechanicalequations of the smart cable are derived. Furthermore, the finite element model of thesmart cable network structure is established. A plane cable network structure is taken asan example to verify the mechanical equations of the smart cable network structuresystem. Simulation results confirm the correctness of the finite element modelingapproach of smart cable network structures.Secondly, the pre-tension design of cable of large cable network structure isdiscussed, which falls into two steps. In the first step, two kinds of pre-tensionoptimization methods for cable network structures are proposed on the basis of theassumption of rigid ring truss, which aim to obtain a set of reasonable pre-tensions in allcables. These two kinds of optimization models are deduced form nodal forceequilibrium equations when nodes are located in ideal positions and solved by theminimal norm theory and the genetic algorithm respectively. The plane and spatial cablenetwork structure examples are given and the results show that these two kinds ofoptimization methods can effectively solve the pre-tension optimal design problem ofcable network structures. In the following, in order to improve the reflector surfaceaccuracy, the method considering effects of the truss deformation on the surfaceaccuracy is proposed by adjusting the positions of fixed nodes on the truss.The method for surface active adjustment of cable network structure is proposed inthe case of small deformation hypothesis. The examples of the plane and spatial cablenetwork structure are carried out to verify the feasibility of the smart cable networkstructure and the effectiveness of the adjustment method. The actuation voltages andadjustment effects in the case of the cable network structure with different pre-tensionsare compared. The numerical results demonstrate that the surface active adjustment ofthe cable network structure by actuators can achieve a high surface accuracy and thesurface active adjustment method proposed is an effective algorithm.