Master Thesis - OUFTI-1

5.3 Static analysis
As described in reference [57], Vega, and so, its payloads, is subjected to quasi-static
loads during ight. So, the aim of this study is to ensure the structural integrity of each
part of the satellite when it is submitted to these steady state acceleration.
5.3.1 Loads denition
The rst step is to clearly dene the quasi-static loads which will be applied on our
CubeSat. For this, the worst case will be considered. This particular case occures if
OUFTI-1 is placed in third position inside the P-POD because, in this conguration, it
has to support the weight of two CubeSats in addition of the quasi-static loads imposed
by the launcher. This conguration is illustrated in Figure 5.7. As remind, the P-POD
will be placed at an angle of 10 ◦ from the vertical.
Figure 5.7: Illustration of the worst case conguration
The maximal steady state acceleration given in reference [57], is the one along the
launcher's longitudinal axis. This acceleration has a value of 6.3 g. In our case, it was
decided to apply a SF of 2 on each acceleration. So, the acceleration along the Z axis of
the Vega frame is 12.6 g. The lateral accelerations, due to the dynamic pressure inside the
launcher, have a maximal value of 1.2 g. So, an acceleration of 2.4 g will be applied along
X and Y axes of the Vega frame.
However, due to the particular conguration of the P-POD, a rotation matrix must be
applied to these accelerations to bring them back in the CubeSat frame (as illustrated in
Figure 5.8).
Note that the CubeSat are placed with their base plate (face −Z) on the side +Z inside
the P-POD (as it can be seen in Figure 5.8). This conguration is the one given in the
ocial documents [58].
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