Flight Operating System (FOS)

• A micro ‘virtual operating system’.
• Enables autonomous determination, control and operation of the CubeSAT.
• Enables seamless shifting between the different modes of the satellite.
• Allows for communications with uplink and downlink capability.
• Allows for software patches to be sent.

Changelog

• vAlpha - Triad, IGRF, MPU, PID and ESC code added. Some utils and tests added.
• v0.1 - Logging, Modes, Uplink/Downlink, Image Queueing and Shell capabilites added. Code structure better defined.

Modules used

• pigpio
• numpy
• pyIGRF
• math
• datetime
• time
• signal
• logging

Structure

.
├── communications/
├── config/
├── control_systems/
├── core/
├── determination/
├── tests/
├── modes/
├── unused/
├── fos.py
└── README.md

Features

UNIX Shell

Subteam - CS

• Allows access to the terminal on the flight computer.
• Can easily send patches, as shell and python scripts.
• Gives us a way to make changes to the satellite software in orbit, should anything go wrong.

Progress - Basic version completed, more features like custom commands could be added.

PID

Subteam - CS

• Widely in control systems of autonomous robots
• Helps in adjusting the satellite to account for unforseen variables and improve accuracy of control systems.

Progress - PID code needs to be verified and tuned.

Global Logging

Subteam - CS

• One logging system throughout the OS
• Multiple levels of logging
• Logs will be sent with data packets and not stored permanently, helping free up memory.

Progress - Logging system is defined, needs to implemented throughout each class. Log flushing needs to be completed.

Uplink & Downlink Capability

Subteam - CS, Electrical & ConOps

• Interfaces with the flight computer and allows smooth transfer of data packets over the satellite antennas.
• Data Packets include telemetry data, logs, images, telemetry and messages. Each data packet estimated to be around 0.5 MB maximum.
• Uplink Capability to take in data from the ground and execute commands through the shell, or perform different functions

Progress - Downlink Capability needs to be coded with the flight computer. Need to figure out what do we exactly need to uplink, currently executes shell code.

Modes & Mode Switching

Subteam - CS & ConOps

• Different Modes for the different missions as well as control of the satellite
• Helps in autonomous decision making based on determination data and switching modes.
• Enables us to conduct multiple experiments like the Imaging and HDD testing autonomously.

Progress - Imaging Mode is defined, other modes need to be discussed, finalized and defined. Mode Switching needs to be thought of.

Autonomous Image Queueing

Subteam - CS

• Automatic queueing of images based on percentage of black pixels in the image.
• Ensures that the pictures with most of Earth in it to be sent first.

Progress - Code complete, and partially tested, needs to be integration tested.