Revolutionary – A Simple Yet Much Stronger Artificial Muscle

By Anupum Pant

Background

Some things are just too simple to be noticed by most adults, rather a child would notice it better. Scientists are the ones who manage to hone their ability to  look at things like a child would see it – Children of course are the best scientists. That is what makes scientists different from most other people. And that is what helps them make elegant discoveries, like the one we are seeing here today.

Now, this may seem like a useless thing to some, but in reality the simple fishing line muscle is a huge step towards creating affordable personal robots, exoskeletons and a host of other earth changing devices. I can’t stop thinking how massive this simple thing could end up being.

The Discovery

A team of researchers at the University of Texas at Dallas, did exactly that. In a simple nylon fishing line, these researchers saw something that everyone till date has failed to notice. They noticed that, by twisting a nylon line into a coil (and heat treating), they could turn it into an artificial muscle. Later it was learnt that a simple artificial muscle made in this manner is about 100 times stronger than a human muscle and can go through millions of cycles without failing.

It’s actually so simple to do that you could make an artificial muscle in your own home. In fact, it works with a variety of other kinds of materials too, but better stick to the tested fishing line for now.

All you need to do is to hold one end of a long fishing line and start twisting the other end (a hand mixer could come in handy here). At some point the line reaches a point where it can’t twist any more, and then it starts getting coiled into a telephone wire kind of a spring. Now it can be heated in an oven (carefully, without melting) and cooled to lock it in this coil shape. There, you’ve got your own artificial muscle.

Working

Unlike what you think it would do when heated, the coil actually contracts and can lift a good amount of weight. An array of such artificial muscle fibres could lift a much heavier weight. as shown in the video below.

At first I found it confusing. It was hard for me to understand, what physics goes inside that makes the coil contract as a whole when it is heated. From the words of a wise scienitist, I found that it works like a chinese finger trap (and then I had to look what this piece of origami was). Whatever the coil does is absolutely elegant. It’s almost impossible for me to explain in words how it works. You might have to watch the video below…

The catch is that the nylon muscles made in this manner are very inefficient, but that can be worked upon.