depends on how precise your machine is as of now their are all kinds of filaments to choose from Kevlar,carbon fiber etc... i have made rc car body's, 12 inch t-rex skull,custom parts for my printer complete fans minus motor. The art section is pretty much limitless. If you know how to program the arduino boards and things of that nature then you can build anything anything electronic. You would just print all your gears and casings to your liking. For example take a push mower cut off the arms add a printed track system with direct drive gears for your motors. add necessary control boards capable of running motors and camera run it from your smart phone. after everything gets put in place scan it mask it and make a body( with proper vent holes) for it ,lets use a shark for this idea lol and boom you have your own custom remote control shark mower lol