One simple but infuriating problem within making silicone soft robots is making a secure and air-tight connection between the tubing that leads to your air source and the soft robot itself. As a solution to this, I've developed these adapters. Once you cast your soft robot, you can use the Customizer script on this page to make the mold for your adapter. Print it out, cast it, fuse it to your robot, insert the tubing, tighten a zip-tie, and you're done!
YouTube video: https://www.youtube.com/watch?v=2bcgIzCQ4Fw
Step 1: Customize it to your soft robot
First you have to use the Customizer script to generate the mold. Here are the different parameters and what they do:
Flange Height: This affects the thickness of the flange (A.K.A. the part that attaches to the soft robot). I recommend any value around 10mm.
Flange Radius: This affects the radius of the flange. It should be large enough to fit against the soft robot perfectly. For this value, it is better to be over than under.
Sleeve Height: This affects the length of the "sleeve" that the tubing fits into. I recommend any value around 10mm.
Tubing Size: For this parameter, put in the outer diameter (OD) of the tubing you are using. For example, if your tubing has an OD of 1/4", convert that to millimeters (6.35mm) and enter that.
Once you've entered these parameters, you can download the customized mold and print it using the print settings above.
Step 2: Cast it
Once you have printed the mold, pour in the same type of silicone you used for the soft robot you are attaching it to. For example, I am using Ecoflex 00-30 for my soft robot, so I'm using Ecoflex 00-30 for my adapter. Let it cure for the required amount of time.
Step 3: Attach it to the robot
Once the adapter has cured, leave it in the mold and spread some more silicone onto it. Do not use too much. Put the soft robot on top, making sure to align it. Make sure the silicone covers all openings. Let this cure for the required amount of time.
Step 4: Secure the connection
Once it has cured, pull the now-attached adapter and soft robot out of the mold. Push a screwdriver through the sleeve of the adapter to clear any blockages. Then insert the tubing through the sleeve and into the soft robot. Use a zip-tie and tightly secure it around the sleeve and tube.
Step 5: Enjoy
Now, you can connect the other end of the tubing to an air source. Happy inflating!