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Magnetorheological Soft Robotics

A soft robotics gripper using magnetic fluid.

Principal Investigator

Dr. Ellen Yi Chen Mazumdar - Sensing Technologies Lab, Georgia Tech

Description

Magnetorheological (MR) fluids are fluids that contains magnetic particles (iron). This yields a substance that is simultaneously liquid yet adheres to magnetic properties. A demonstration of the fluid can be found here .

I built on top of the work of Balak and Mazumdar (2021) , who investigated the applications of MR fluids in robotic valve systems. The question posed was, is it possible to create a soft robotic gripper with MR fluid?

Design

In pursuit of this question, I designed a prototype pneumatic MR fluid gripper.

The design decisions are best explained by detailing the mechanics of the MR gripper.

  1. The object being gripped is placed between the magnet and the air dome/MR fluid torus.

  2. The MR fluid torus is filled. It is attracted by the ferromagnet and proceeds to clamp the object. The object is now officially gripped.

  3. The process of releasing the object begins. The MR fluid is drained from the torus. However, as the magnetic attractive forces are too great for the MR fluid chamber's pressure to overcome, significant liquid still remains and grips the object.

  4. The air dome is now filled. This forces separation between the MR fluid and the object, allowing the object to slightly move to adjust to the air dome's force on it. A repeat filling and releasing of the air dome allows the object to slowly budge until it is fully released by the gripper.

To see the apparatus in action, please view the demo . Unfortunately, the final report on this project has been lost with time and cannot currently be found.