Pneumatic actuators contract or inflate when air is applied. Made of silicon rubber, thermoplastic, or other soft materials, they have user- friendly interface, as well as better deformation ability and flexibility compared with mechanical structure.
I have watched a video about how to make McKibben actuators on YouTube, and got interested in them. The McKibben actuator is one of the most well-known actuators, due to the simplicity of its design and assembling. It has been used in a wide range of applications including robotics, orthotics, and industrial automation.
There are 3 kinds of McKibben actuators:
Inflated McKibben actuators will inevitably bend due to gravity and manual errors during fabrication. Inspired by papers on silicone pneumatic actuators, where researchers make the actuator bend by adding a non-stretchable layer, I glued a piece of plastic on one side of the sleeving. And I found that this method works for both extensible Mckibben actuators and actuators with bellows. Furthermore, the position and size of the plastic influence the bending.
There is a step where I need to put the sleeve on the stick before heating it. I discovered that the shape of the stick can affect how McKibben actuators inflate. So I 3D-printed different kinds of sticks to find out the correlation.
This mechanism can be applied to other objects. What I want to express in this design is a responsive environment. For example, in the future, when your hand is approaching the light switch, it may stretch towards your fingertip as if it was alive.
This project is part of my undergraduate thesis. The other part can be found in the pneumatic gloves project.
