The first goal on the project was creating soft material valves small enough to fit on the tiny bee. Designing ideas which can be fabricated with current technology is a big challenge in soft robotics. To see what was possible, I tested the 3D printer's (Carbon 3D) extreme resolutions for typical structures. Based on the data I gathered, I tried several possible designs of soft material valves, which let the exhaust out and fuel in during the interval of combustion. After fabricating and testing dozens of valves, and repeating to reach optimality, I found that a valve which consisted of two pieces of different materials could work exactly as required. Another part of the RoboBee is the membranes which connect and actuate wings. For this part we used molded silicone, because 3D printing still couldn’t process a material with the required elasticity. My colleague and I found the appropriate silicone rubber and the right thickness for the membranes to let them inflate at a high frequency. This project opened the door of soft robotics for me. Also, it made me notice the limitations of 3D printing for soft robotics.

Different Designs of Valves