Satellite Configuration Design - Finite Element Analysis for Satellite Structures - page 32

X

(Direction of flight)

Reaction wheel

Skewed gyro

Star sensor

Interface unit
Gyro

Magnetorquers

Magnetometer

Y

Gyro

Interface unit

Basis block
case

Interface unit

Gyro

Reaction wheel

Reaction wheel

MBEI

Z

Fig. 2.9 Final packaging arrangement for the basis unit block of Small Sat

The next step is to complete the main load path structure and find suitable
surfaces to mount the remaining equipment. Two frames can be used to connect
the basis block case with both base and mounting plates, so they have suitable
shape and size to enclose the payload inside. Each frame consists of four plates
connected together to form a square cross-section, which provides integrity with
the basis block case. The first frame that connects the basis block case with the
base plate is called the upper frame, while the other that connects the basis block
case with the mounting plate is called the lower frame. Both upper and lower
frames provide enough area on their external surfaces to mount some of the
remaining equipment. In addition, the inner surfaces of both the base and mounting
plates can be employed to mount the rest of the equipment. Figure 2.10 illustrates
the location of both upper and lower frames.
The battery is considered one of the most difficult equipment to fit inside the
satellite because it is heavy, large, and needs a special location protected from
direct exposure to the sun or earth. Moreover, it should be packaged as close as
possible to the launch vehicle interface and near large power consumers and the
solar arrays. The power subsystem electronic component, PCU and CLU, should
be mounted as close as possible to the battery. Therefore, Small Sat battery will be