Crafting Material Interfaces

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.

Finger with Cotton and Pepper

The finger failed to pick up the stick when actuated with air.

I had much more success with water-soaked cotton.

Successful Pickup with Water Soaked Cotton

It also manages to pick two up, albeit a little badly.

Pickup of Two Sticks

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.

Unsuccessful Pickup with Soy Milk