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Fiber reinforced polymer laminates are susceptible to transverse low velocity impact which can cause significant damages, such as matrix cracks, delamination and fiber breakage. A 3-Dimensional (3-D) finite element model (FEM) is presented for the progressive damage analysis of fiber reinforced laminates subjected to low velocity impact. The constitutive equations of material used in the FEM are based on the continuum damage mechanics (CDM). The modified HASHIN failure criterions are used in the material model to detect the initiation of all the failure modes of laminates. A simplified material stiffness degradation scheme is used to characterize the material degradation due to damages. The failure criterions and material degradation scheme have been incorporated in the software ABAQUS/Explicit through the user defined material subroutine VUMAT. The available experiments of thin carbon fiber reinforced epoxy laminates subjected to low velocity impact were used to validate the developed FEM. The good agreement of the impact contact force history and damage area between the analysis results and the experimental data shows the validation of the developed FEM.

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The M-shaped boom is a support structure that can be packed and launched and deployed in orbit using stored elastic strain energy. This work attempts a method to optimize the M boom. The response surface method was used to fit the finite element (FE) results to obtain surrogate models for the strain storage and the fundamental frequency in the deployed state, and the average errors between the surrogate model results and FE results were 1.56% and 0.9% respectively. The influence of different design variables on the results is analyzed by using surrogate models. Considering the requirements of boom deployment, a non-dominated sorting genetic algorithm is used for multiobjective optimization. The optimization targets the maximum strain stored energy and the maximum fundamental frequency, with the constraint of boom mass. The optimization results are at the Pareto frontier.