What are CubeSats?

A CubeSat is a low-cost, small footprint satellite that usually operates in Low Earth Orbit (LEO). They are often developed by smaller organizations like student teams as an affordable route to get involved in the space industry.

CubeSats come in a range of standard sizes, the smallest being 1U, a 10cm x 10cm x 10cm satellite. Other sizes, such as 3U and 6U, have form factors that are multiples of the 1U (e.g. 3U form is 10cm x 10cm x 30cm). A full list of sizes can be viewed here, but it's not important to our purposes at Orbital.

Image Source: https://www.researchgate.net/figure/Depiction-of-the-most-typical-CubeSat-sizes-1U-2U-3U-image-courtesy-of-Clyde-Space_fig1_286288134

Image Source: https://www.researchgate.net/figure/Depiction-of-the-most-typical-CubeSat-sizes-1U-2U-3U-image-courtesy-of-Clyde-Space_fig1_286288134

The CubeSat that UW Orbital is designing will be a 3U, as per CSDC requirements. CubeSats often hitch rides along with larger satellites, so the launch cost associated with a 3U is roughly $200K.

Once the main satellite has deployed, CubeSats are often released via a "dispenser", which includes a spring that pushes and releases the satellite once a signal is sent to the dispenser to open its hatch. Dispensers are provided by launch providers, and often covered under launch costs. They are often bolted onto parts of the launch vehicle payload carrier, wherever there is space available.

In rare cases, satellites are sometimes launched from the International Space Station, via an astronaut that throws the satellite into orbit.

Subsystems

There are six main subsystems that help a CubeSat tick.

Attitude Determination and Control Systems (ADCS)

The ADCS subsystem is responsible for assisting with orientation control of the satellite within space through tools such as magnetorquers and reaction wheels, as well as sensors (IMUs, sun sensors, GPS) that assist in determining the location and orientation of the satellite.

ADCS Architecture

Communications

The communications subsystem handles the interface between the ground station and CubeSat. Major components relevant to this subsystem include the antenna, transceiver, and ground station equipment.

Comms Architecture

Electrical Power Systems (EPS)

The EPS subsystem is responsible for power production, distribution, and management. Major components of this subsystem involve the solar panels and batteries.

EPS Wiki

Command and Data Handling (CDH)