Monowheel submarine
thingiverse
A one-wheeled, amphibious vehicle propelled by pedal power is the design in question. If you appreciate this concept, kindly vote for it to help me win a 3D printer - http://www.instructables.com/id/Monowheel-Submarine/.
Download Model from thingiverse
With this file you will be able to print Monowheel submarine with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Monowheel submarine.