Giving You The Finger, or How to Make a Homemade Small-Footprint Jamming Device (using Fluids instead of Air)
Having done research on soft robotics actuated by air, I wanted to create a simple device that will allow me to test and play with jamming with various fluid instead of air. I was inspired by the Japanese soft robotics hand that we showed last week.
The voiceover and subtitles explains how this works, where a soft rubber pouch is actuated by pressured air. The simplified demonstration below shows this, a syringe of air changing the dimensions of the finger-pouch:
I decided to use a medical syringe as the air pump, examination gloves as the membrane, rubber bands to provide a seal, and soaked cotton balls as the jamming content. I used a bunch of lightweight dental sticks as pickup objects.
So after snipping off the fingers of the glove, I made this:
a surrealistic little finger.
I wanted to test it with unsoaked cotton ball first, as well as a combination of unsoaked cotton ball and ground black pepper.
The finger failed to pick up the stick when actuated with air.
I had much more success with water-soaked cotton.
It also manages to pick two up, albeit a little badly.
I tried fluids with different viscosity, first honey, and then soy milk.
But viscosity changes the effectiveness dramatically, such that I seem to achieve a stronger suction effect, but without a corresponding increase in successful pickups.