Week 11: Mark F.

I wrote my research into our Chapter 2 of our report documenting the process of deciding what is the best material to use when 3D printing the parts of our rover.

2.2.6 3D Printed Parts

Several materials were evaluated for their suitability in a space-based application. PEEK and ULTEM were considered due to their high strength, heat resistance, and that it's already established as a usable material to make high stress aerospace components. Studies indicate that these materials perform well under extreme thermal conditions and radiation exposure, making them ideal for long-term deployment in space. Titanium and aluminum alloys were also taken into consideration as they are widely used in spacecraft and rover construction due to their lightweight properties and corrosion resistance. Research on additive manufacturing in space has shown that titanium 3D printing is a viable option for structural components requiring high strength-to-weight ratios. Carbon fiber reinforced polymers (CFRP) were also investigated as a lightweight alternative with high durability, commonly used in aerospace structures for their excellent mechanical properties and low density.

After evaluating various material properties and costs, PETG was selected for the Astraeus prototype due to its printability, affordability, and durability in Earth-based conditions. PETG is known for its ease of printing, requiring moderate temperatures and not necessitating specialized equipment like PEEK or ULTEM. In terms of cost, PETG is significantly more affordable than aerospace-grade polymers and metals, making it ideal for a project with limited resources. 

Figure 2.14 - Overture PETG 1.75mm 3D Printer Filament

Astraeus incorporates PETG for all of its structural and functional components. Structural elements such as chassis components, sensor housings, and lightweight support structures are fabricated using PETG due to its strength and ease of manufacturing. Mounting brackets for motors, sensors, and electronic components are also printed in PETG, which allows us to design parts specifically for our project that can be easily modified during testing. It is important to note that for future iterations of Astraeus specifically for space deployment, the design will require alternative materials that can handle both higher levels of stress and radiation. The use of PETG in the Astraeus prototype ensures a balance between cost, ease of manufacturing, and structural integrity of Astraeus for Earth-based testing. While PETG is not suitable for final space deployment, it effectively allows for iterative development and proof-of-concept testing of the rover’s design.