Tubular, bifurcated structure production process

Figure 7.36 Machine process for the production of a nonnear-net-shaped tubular, bifurcated structure.

Although widely being explored, the majority of the automated production of 3D braids is often limited to fabricate constant cross-sectional 3D braid geometry. However, the production of a tubular or bifurcated structure requires variations in the geometry of the cross sections. This leads to manual interference in the production process, which slows the production process and constrains the use of 3D braids to products with small quantities. Thus, development of a fuUy automated process will clear the way towards the production of 3D braids in large quantities and allow the use of 3D braids in wide areas of application. Examples are the preforms in composites, for example, stmctural stiffeners in car bodies or as stents in a medical devices. 

The bifurcation conditions and the UM method to braid a tubular stmcture can be combined to develop a process that allows for the production of bifurcated, tubular stractures. To produce a closed structure, three different cross-section geometries and subsequently two cross-sectional changes are required. In Figure 7.33, the tubular bifurcated stmcture and the cross-section geometries are depicted. These are one tube (1), a figure 8 (2) and two tubes (3). 

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