Master Thesis - OUFTI-1

I xx , I yy and I zz are called the moments of inertia while the other elements are called
the products of inertia.
This tensor can be calculated from any point of the structure. However, to facilitate
its calculation, it is preferable to dene it from the CoG. Thus, the inertia tensor linked to
our reference frame is given in Equation (2.4.9).
⎛
2.104 6.025 10 −2 1.69 10 −2 ⎞
I CoG = ⎝6.025 10 −2 1.757 −9.641 10 −2 ⎠ × 10 6 g mm 2 (2.4.9)
1.69 10 −2 −9.641 10 −2 2.019
In addition, the principal moments of inertia can be calculated, as well as the principal
axes, to completely dene the inertia properties of OUFTI-1. They are given in Equations
(2.4.10) to (2.4.12) and (2.4.13) to (2.4.15) respectively.
M 1 = 1.715 × 10 6 g mm 2 (2.4.10)
M 2 = 2.05 × 10 6 g mm 2 (2.4.11)
2.5 Mass budget
M 3 = 2.114 × 10 6 g mm 2 (2.4.12)
⎛ ⎞
−0.159
A 1 = ⎝ 0.938 ⎠ (2.4.13)
0.307
⎛ ⎞
−0.042
A 2 = ⎝ 0.305 ⎠ (2.4.14)
−0.952
⎛ ⎞
0.986
A 3 = ⎝0.164⎠ (2.4.15)
0.009
As already mentioned on chapter 1, one of the general constraints for a CubeSat is:
"Each single CubeSat shall not exceed 1 kg mass ".
To ensure that OUFTI-1 respects this requirement, each component of the CubeSat
was weighted. However, at the end of this year, some of them are not yet nished. For
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