COLLABORATIVE DYNAMICS TOPOLOGY OPTIMIZATION OF COMBINED STRUCTURE

An engineering structure is usually composed of multiple components for carrying loads. Between them, the loads or vibration energies are transferred through the linkage members. Then, the layout and properties of the linkage members have a great influence on the topological configuration, mechanical performance and load-bearing capacity of the entire structure. In this paper, the collaborative dynamic topology optimization of the configuration of the combined structure and the layout of the linkage members between components is studied. A spring connection element is employed to represent the linkage member for its restraint behaviors. With the constraints of the material usage and the linkage member number, the dynamic compliance of the entire structure is pursued for minimization under the external harmonic excitation. By taking the relative material densities of the load-bearing members and the relative stiffness of the spring connecting elements as the design variables, the topological configuration of the combined structure and the layout of the linkage members are optimized collaboratively with use of the gradient-based optimization algorithm. By comparison with the optimal topology designs of the integral structures without linkage members, the topological configuration changes of the combined structure and the influences of the layout of the linkage members are illustrated on both the overall material distribution and dynamic properties. In addition, the dynamic topology optimization of the combined structure is implemented with the linkage members subjectively arranged. Numerical results show that the dynamic compliance of the collaborative optimization results for the combined structures are always greater than the equivalent integral structures. However, the variations of the structural natural frequencies of the combined structures are usually unpredicted mainly due to the changes of the corresponding mode shapes, which can provide a more superior structural configuration and connection layout in the process of the conceptual design stage of a practical structure.