Strength Analysis - Finite Element Analysis for Satellite Structures - page 90

Fig. 4.2 3-D model of Small Sat structure used in the strength analysis process [ 6 ]

fastening points, because the rotation hinge do not transfer rotation inertia loads to
the satellite structure. For other equipment, one of two methods can be used for
equipment modeling:

1. The equipment is modeled as a pyramid with zero-density elements. The head
of the pyramid is located at the equipment's center of mass and its base points
are at the center of the fixation locations with its structural module. A mass
element is attached at the head of the pyramid to represent the mass of the
equipment with its moments of inertia. Zero-density elements used in the
pyramid modeling have the same properties of aluminum alloy AMg6.
2. The equipment is modeled by connecting its center of fixation locations and
then this closed contour is extruded to double the center of mass of the
equipment. The volume of such a shape is calculated, and the suitable density
that will make it equal the equipment in mass is evaluated. Equivalent density
elements are used to model the equipment with the same properties of alumi-
num alloy AMg6.
The first method is more commonly used for equipment modeling because it
provides more accurate modeling. This method represents the closest model for the
actual equipment, because it models the mass of the equipment with its moments