Master Thesis - OUFTI-1

environment. Then, this model is exploded in several parts to isolate each component.
Finally, a behavior and a material are assigned to each of them and they are linked together
using the assembly methods available in Samcef (the methods used must be as close as
possible from the real connection between the two components to obtain accurate results).
5.2.1 Materials properties
Firstly, the properties of the materials used for manufacturing the several components,
are presented in a single table (see Table 5.1). This allows to avoid multiple repeatings of
tables including these properties through this section. Afterwards, these materials will be
just mentioned and their properties will not be reminded. It should be noted that these
properties were found using the CES software.
Materials Young's moduli (GP a) Poisson ratios Densities (kg/m 3 )
Al − 5052 H32 71.795 0.33675 2685
Al − 5754 69 0.33 2700
Al − 7075 T 6 72.5 0.33 2800
Al − 7075 T 73 71 0.33 2800
FR 4 20 0.3 2200
Stainless steel 205 0.3 7850
Table 5.1: Properties of the materials used in OUFTI-1
5.2.2 Main structure
The main structure of OUFTI-1, which corresponds to the CSK structural parts,
was modeled using shell components. Indeed, the thickness of the base and end plates
(1.52 mm) and the one of the chassis (1.27 mm) are negligible with regard to their other
dimensions (100 mm), which allows to use this type of modeling. All these components
are made of Al − 5052 H32.
The base and end plates are connected to the chassis by several M3 × 4 mm stainless
steel screws. To model this type of connection in Samcef, the procedure is the following
one:
• A point (vertex) is placed at the center of the two holes (one on the considered plate
and the other on the chassis).
• These vertex are linked to the wire of their respecting hole using a "mean" assembly.
This type of assembly determines the mean rotation and displacement of the nodes
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