ASI-408 Galassia-5 Mechanical Design and Environmental Testing
(CDE4301 Final Report)

1.1 About Galassia-5

Galassia-5 is a student-led 6U CubeSat mission in collaboration with the Engineering Design and Innovation Centre (EDIC) and the Department of Electrical and Computer Engineering at the National University of Singapore (NUS). Principally funded by the Future Systems & Technology Directorate (FSTD) and building upon the success of Galassia-1 (2015) and Galassia-2 (2023), the key Mission Objectives for Galassia-5 are:

1. Demonstration of On-Orbit AI-Based Earth Observation Image Processing:
   Galassia-5 will demonstrate AI-based image processing onboard the satellite, enabling real-time detection and classification of key features like ship positions. Onboard processing prioritises critical data and reduces data downlink volume. This will significantly speed up response times compared to ground-based analysis.

2. Demonstration of AI Neural Processing Unit (NPU) in Space:
   Galassia-5 will test a space-qualified NPU in orbit for the first time. NPUs are specialized processor chips designed for efficient machine learning tasks like image recognition and pattern detection. Demonstrating their performance in space is crucial for advancing autonomous satellite systems that can adapt in real time to dynamic events.

3. Demonstration of Direct-to-VSAT Ku-Band Radio Downlink:
   Galassia-5 will test a high-speed communication link from the satellite to ground users via Ku-band Very Small Aperture Terminal (VSAT) systems. This approach enables real-time transmission of priority data to field teams using portable VSAT terminals, providing essential support for rapid decision-making in remote sea or disaster-affected areas with limited infrastructure.

Some Use Cases for Galassia-5 include:

• Humanitarian Rescue (Identifying collapsed buildings quickly to guide first responder efforts)
• Forest Fire Surveillance (Rapidly Identifying regions of fire to help firefighters arrest the spread of wildfires)
• Anti Piracy Surveillance (Maintaining real time situational awareness over wide Swaths of Ocean)

The Concept of Operations for Galassia-5 on an Anti-Piracy Surveillance mission is shown below:

Fig. 1.1.1 Concept of Operations - Shipboard detection of Vessels using EO Imagery for Anti Piracy

The table below provides a summary of Galassia-5’s Key System Specifications.
Table 1.1.2. Key System Specifications of Galassia-5

A CAD mock-up of Galassia-5 is shown below, showing the Coordinate System in use.

Fig. 1.1.3 CAD Model of Galassia-5, showing the coordinate system in use

1.2 Galassia-5 Stakeholders and Partners

Table 1.2.1 Galassia-5 Stakeholders and Partners

1.3 Role of Mechanical Subteam

The Mechanical Subteam supports the Mechanical Design needs of the Galassia-5 project, in collaboration with the Bus Contractor (NuSpace) who will be constructing the Satellite Bus.

Currently, the Mechanical Design problems that the team is looking into are:

1. Mechanical Design, Analysis, and Manufacturing of CubeSat Frame Structure (Victor)
   • Developing a particular test plan for mechanical tests necessary to qualify the satellite for flight
   • Design, analysis, and manufacturing of CubeSat frame components
   • Development of Killswitch Mechanism
2. Thermal Certification of the CubeSat (Tze Yee)
   • Obtain a preliminary orbital temperature profile for Galassia-5 to inform a Thermal Management Plan
3. Mechanical Ground Support Equipment (MGSE) (Jin Guang)
   • Design of MGSE customised to Galassia-5 to support the Integration, Testing/Qualification and Transportation of the CubeSat