Satellite Configuration Design - Finite Element Analysis for Satellite Structures - page 17

Fig. 2.2 Mass of LV payloads to be injected by Dnepr into sun-synchronous orbit [ 2 ]

launch vehicles require a modification in their interface configuration to provide
the possibility of launching of a satellite 200-300 kg, which is unacceptably
costly. Arian 4, Arian 5, and Dnepr provide the possibility of launching a satellite
of 200-300 kg without modification. All launch vehicle types, except Taurus,
assure appropriate orbiting accuracy.
Figure 2.2 [ 2 ] shows the total mass of the launch vehicle payload to be injected
by Dnepr LV into sun-synchronous orbit at different inclination angles. From the
figure, the allowable payload mass of Dnepr LV at an altitude of 668 km with
inclination 98 o slightly exceeds 800 kg, which is suitable to launch a series or
group of small satellites. After comparison based on the above discussion and cost
criteria, Dnepr Launch Vehicle is found to be the suitable one to launch Small Sat.
For Dnepr Launch Vehicle, the spacecraft ''Small Sat'' is installed inside the
space head module (SHM). The SHM is composed of the fairing, cylindrical
intermediate section, adapter, protective membrane, and gas dynamic shield
(GDS) or encapsulated payload module (EPM). Layout schematic of the standard
length SHM (with both GDS and EPM) is shown in Fig. 2.3 . SHM design allows
for multi-tier spacecraft layout. One of the options for such layout is shown in
Fig. 2.4 .

2.5 Satellite Composition

A satellite consists of a payload, which is the mission-specific equipment, and a
collection of subsystems [ 1 ]. A subsystem is a group of components that support a
common function. There is a difference between the payload and the rest of the
satellite subsystems, because the payload is typically unique for a given mission,
whereas the other subsystems may be able to support different missions. In the next
section, a closer look is provided at essential subsystems, focusing on features and