TLDR: Through some friends at Uni, I found out about an antweight competition, so I started modelling something in Fusion to compete, got a little carried away, and here I am now 
I have printed out a few versions while designing, but I’m aiming to build a complete working unit in a couple of weeks once I’m back into the flow of University (for testing the drum, there is an arena at Uni, and I am looking into options for making a test box). I have made a BOM & Mass Sheet to keep the design under 150g, and once I’ve built and tested it, I plan on sharing the design on GitHub/Printables/MakerWorld. I’m also dabbling with simulating the drum to get an idea of how it’ll behave. Currently made sure, through FEA pending actual tests, that it won’t deflect too much when rotating, and the next steps I want to take are to learn the basics of Ansys to simulate impacts on the drum. I have some ideas to try to make it withstand direct hits from metal vertical spinners.
Some current features of the design:
- Interchangeable TPU bumpers (several variations)
- Double shear N10 motor mounts (see cross-section below)
- Variety of drum options (currently at 9)
- Silicone moulded tyres
- SLM titanium front stabilisers/forks
- Can be driven inverted
Any feedback on the design so far would be greatly appreciated 
(Also, I am definitely a new kid on the block, so hi everyone 
)