Admit it, the moment you heard of 3D printing you imagined a giant robot stepping out of a machine. 3D printed robots that walk right out of the printer are coming, but taking an unexpected direction.
As you can imagine, robots are complex machines; each motion typically requires a concert of rigid parts assembled together. Therefore robots would need to be constructed from a variety of materials, including a power source and electrical components as well as extremely accurate mechanical parts.
3D printers are fantastic for many things but they still have limitations. One of the current challenges to 3D printing technology is that most machines can only produce a few different materials at once or moving parts have comparatively large tolerances (if they are even possible at all). Currently you can print most of the components for a functioning robot, but you have to make them separately and then assemble afterwards (although some designers have figured out how to get around this with our strong and flexible plastic). This is exciting but not quite the revolutionary way 3D printing can be imagined as a futuristic, automated way of making.
Scientists are already researching solutions. Multiple institutions including Carnegie Mellon, MIT and Harvard are working to create hydraulic mechanics that could walk right out of the printer. The key here is that the robots are designed such that when a liquid is pumped through it, it changes the form of part. By expanding and contracting portions of the robot in a controlled way the robot can move. Therefore, instead of using things like gears, which would need to be assembled, you literally “just add water” to these robots for it to begin moving.
As the materials available for 3D printing continue to expand we look forward to designs that rethink the way we approach motion and mechanics. How would you design a 3D printed robot?