I was really happy after finishing the design for the frame structure, and it looked great to me! The next day, I went to my school to try printing out the parts at the design lab. After waiting for two days to actually go and see my design in person, I was disappointed to see that the print had failed. I had not taken into consideration the constraints imposed by 3D printing, designing the model such that during the printing process the extruder would always be able to place filament above an adequate surface, and not topple due to a change in center of gravity. After speaking with my design teacher and reflecting on the basic structure of the frame, I realised just how over-engineered the design truly was. While designing my frame, there was one key constraint that I neglected during the iterative process; the thruster placement. After reading through more of Fossen's book on the marine vehicles, in order to maximise the control and available degrees of freedom, I realised would have to strategically place and orient my thrusters. 

I was back to the drawing board with the design,