Description

To verify the system level design, a block diagram was created mostly from scratch using reference designs and requirements. It was then compared to the diagram in the main page, and notes are given on the differences. Also included is the sources to the reference designs and other information used

Tasks

Block Diagram

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Figure 1. Block diagram created to compare with the system level design diagram on the main page.

Differences with System Level Design

Here are the differences between the block diagram and the main system level design diagram.

Multiple Maximum Power Point Tracking (MPPT) Chips

Other designs included multiple MPPTs [1],[5]. These systems were designed for each solar panel on the CubeSat to have its own MPPT. However, solar panels on opposite sides of the satellite can share one MPPT as only one side will be illuminated at a time.

Remove Before Flight (RBF Pin)

CubeSat designs included a remove before flight (RBF) pin, that would be inserted into the satellite and removed before launch [1],[2],[5]. The inclusion of the RBF pin was also discussed in the CubeSat Design Specification [3]. If the pin is in the satellite, then all power should be cut off. Though in the block diagram, power can come from the ground station equipment (GSE).

Multiple Deployment (DEP) Switches

CubeSat Design Specification [3] stated that there must be at minimum one deployment switch. Though the reference designs [1], [2], [5] include three that were placed at the corners of the satellite. Having three switches will increase the risk of one failing to actuate upon release, though it will reduce the risk of turning the satellite on before release.

Connection to Ground Station Equipment (GSE) Fuse Moved

The block diagram moved the fuse after MUX #2 to before it at the connection to ground support equipment (GSE). With the fuse here, if the GSE were to supply to much power, melting the fuse, then the satellite can still operate from battery power.