Automated assemly of large composite preforms for reinforcement applications in aerostructures

Abstract

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.There is considerable interest in the use of textiles, which are known as dry fabrics, for the construction of structural preforms of varying complexity. Cost reduction is a key factor in the future expansion of textiles and this can, to a great extent, be achieved by automation of the preform assembly process. Non-Crimp-Fabrics (NCF) offer significant potential for the process automation, due to an increased deposition rate and high structural performance.This work is focused on the development of a novel methodology which can be used to generate a fully integrated automation cell to produce three dimensional (3D) components. Aautomation technique has been developed, which enables large reinforcement structures of I, C, J, and T shape to be readily produced for subsequent forming into required shapes when loaded into the mould. The preform is produced as a single piece, to reduce associated assembly and handling times. The proposed technique has been realised in design and implemented as a novel tool for forming the three-dimensional components in a single stroke for the aerospace applications. The resulting tool has been integrated into a fully automated manufacturing cell, providing an opportunity for a successful proof of principle application of such a device. The automated manufacturing cell has an integrated by robotic tacking device (RTD) which helps to produce preforms with a high degree of accuracy, where the fabrics are arranged in the required format to match the service loading of the component. Mechanical tests and numerical analyses have been conducted on a typical I-beam section to investigate the effects of both tacking position and the loading conditions on the consolidated product. Numerical analyses investigations have produced largely encourage results