Gripper not working? Here are some troubleshooting tips you can try.



Check for air leaks. If your gripper doesn't inflate at all, listen and feel for air leaks when you squeeze the bulb. If you do have air leaks, you can patch them up with a fresh layer of silicone rubber, let the material cure, then try again.



Check for clogged channels. Hold your gripper up to a bright light and look at the interior air channels. Can you see them in all four legs? If you can only see parts of the channels, or can't see them at all, they are probably clogged, which means you used too much "glue" in Step 9. Unfortunately there is no way to repair this - you will have to start from the beginning. Luckily, you should have plenty of Ecoflex left over, and your mold, squeeze bulb and tubing are all re-usable.



Make sure the tip of the air tube is in the central chamber. Hold your gripper up to a light and look for the tip of the air tube. Did it make it all the way in to the central chamber? If you didn't fully puncture the outer wall of the robot, or pushed the tube too far and into the opposite wall, then the end will be sealed shut by rubber, and prevent air from getting into the channels. Wiggle the air tube until the tip is free in the central chamber.



Some legs inflate better than others. If all four of your legs don't inflate symmetrically, first check each individual leg for clogged air channels, as described above. If none of the channels are clogged but the legs still don't inflate symmetrically, you can layer some extra silicone on the legs that are inflating the most - this should make it harder for them to inflate, allowing more air pressure to divert to the other legs. The material has "nonlinear" behavior - this means that, instead of always inflating gradually with air pressure, it could not inflate at all and then suddenly "jump" and inflate. So, if one leg is slightly weaker than the others (maybe due to some slight differences in wall thickness from the molding process), it might inflate first while the others don't inflate at all. Strengthening this leg with additional silicone may prevent this.