There is no better way to learn robotics and 3D printing than building your own robots. mikey77 has shared a guide that shows you how to build your own robot assistant. You are going to need Picaxe microcontrollers, a 3D printer, 12 volt air compressor, battery, and a few parts to get started.
The robot’s head, body, arms, mounting brackets, air valves, and the artificial muscles are all 3D printed. You can find the instructions for the project here.