Satellite Structural Design - Finite Element Analysis for Satellite Structures - page 76

Fig. 3.34 Upper frame

Rivets

The height of the upper frame is 310 mm, and it has a square cross-section with
outer and inner dimensions equal to 551 and 499 mm, respectively. The upper
frame milled walls have rectangular cross-section stiffeners of 10 mm width and
4 mm thickness. 86 mm diameter holes are provided in the upper frame for
installation of the eight studs connecting structural subassemblies to the satellite
case. One wall contains four seats for mounting the bracket of the battery. The
mass of the upper frame is 5 kg.

3.5.5 Lower Frame

The lower frame consists of six milled walls connected together by rivets as shown
in Fig. 3.35 . The lower frame structural walls are made of aluminum alloy AMg6.
The height of upper frame is 420 mm, and it has a modified square cross-section
with outer dimensions equal to 547 and 556 mm and inner dimension equal to 503
and 503 mm. The lower frame walls have rectangular cross-section stiffeners of
10 mm width and 3 mm thickness. Eight 6 mm diameter holes are provided in the
lower frame for installation of the eight studs connecting structural subassemblies
at the satellite case. The lower frame provides mounting seats for the X-band
electronic module, two S-band electronic modules, GPS electronic module, and
three modules of the on-board digital computing complex. One wall contains two
seats for mounting PCU and CLU. The mass of the lower frame is 5.3 kg.

3.5.6 Rotation Mechanisms

Rotation mechanisms provide connection of the solar arrays with the satellite
body, smooth rotation of the solar arrays into ready-to-work position, and their
fixation

in the ready-to-work position during satellite lifetime. A rotation