Universal/Jamming Gripper Prototype

I made my own version of the Universal/Jamming Gripper created by John Ahmend.

You can do this too in 5 minutes! The recourses you need are:

  • Plastic syringe (ask your pharmacist, he/she will look weird but give it to you if you don't look like a drug addict)
  • Balloon (a small one)
  • Ground coffee
  • Duct tape
  • Piece of cloth/woven tissue (should act as a filter to let the air pass but not the coffee so keep this in mind)
  • Superglue

To assemble it you have to go through the following steps:

  • Step 1 - Cutt off the tip of the plastic syringe as cleanly as possible.
  • Step 2 - Cover the hole that is now in the syringe with the piece of hankerchief and glue it reasonably tight with the superglue. Let it dry.
  • Step 3 - Fill the balloon as good as you can with the coffee. This is a difficult step! It might help if you fill the balloon with air a few times so that it stretches.
  • Step 4 - Make sure the syringe is closed so that it does not contain any air. Then pull the neck from the balloon over the syringe, and make sure you don't trap any air. If you do trap air, try to get it out as much as possible as it will drastically decrease the performance of your gripper.
  • Step 5 - Tape the balloon and the syringe together as tightly as possible using the duct tape.

Here is the gripper in action!

The cool thing about this gripper is that you don't need a pump or anything pneumatic. So if you could find a way to professionally make this, and actuate the seringe with a solenoïd, you can turn this into a very compact and fast device which has all the actuators on board. This would make it fully electrically controllable.

I quickly sketched up an idea I had for this in which I added some extra "fingers" which would make the universal gripper even more universal ;). The first part of the finger would be driven with a small motor and a worm wheel to block it when the motor is not on. The second part part of the finger would be driven by small linear actuators. I never really built this, it's just an idea.