The human body is supported by an internal skeleton, whereas the insect body by an exoskeleton. Where are we in the development of human exoskeletons? Kaija Põhako-Esko, a materials scientist, is equally at ease in the laboratory and behind the loom.
Humans began protecting their bodies with softer materials long before the invention of rigid body armor — textiles are one of the oldest materials known to mankind. When did this art form emerge?
Weaving looms have existed since the Stone Age and the present day looms are not very much different from their ancestors. Our textile technology has been refined throughout the centuries, so why don't we now use these materials and production techniques in science — integrating robotics and textiles — to create garment-like exoskeletons?
What are exoskeletons mainly used for today?
There are many different types of exoskeletons with different functions. One of the most common applications is in medicine as a mobility aid for people with limited mobility. A similar application exists in sports to enhance a person's physical ability. There are also industrial applications, such as preventing injuries and overexertion from forced postures.
When did it first occur to you that this old stuff could be helpful to solve future problems?
I have been fascinated by textiles since I was a child, and my hobby is also textile handcraft. So, when I first started studying materials science, I envisioned a career in textiles. Years passed, and I eventually found my way, specifically by fusing chemistry, robotics, and textile techniques to develop technologies for a garment-like exoskeleton.
There are a lot of new components when we move from the woven belts of traditional costumes to this laboratory for the development and creation of exoskeletons.
Yes, we have a textile material here to which different polymer-based functional layers are applied. They contain, among other natural bio-polymers, gelatin and chitosan, which are derived from insect chitin. There are also carbons and ionic liquids that are liquid at room temperature... What comes to mind when you think of robotics?
Flashing lights, wires, metal...
Yes, something quite different from us. However, in soft robotics we want to connect devices to soft tissues such as skin, internal organs or other tissues in our bodies, as well as to other living beings or to objects [by soft linkage.]
Connect... Does this imply that the two will merge into one another seamlessly?
They can transition seamlessly, but what we really want is for the tissue and the device to work together. The goal is for the robotic device to be soft and compatible with living tissue, moving similarly to tissue and possessing tissue-like properties.
So this is an example of bio-inspiration?
For example, a "robotic" plant, or one that behaves like a robot, is wild oat grass.
In the autumn, the seeds of wild oats ripen and fall off, becoming moist and moving along the ground in search of a hiding place in the soil.
Does it come to life once it starts rolling on the ground?
You could say that, despite the fact that it is still dead matter: there are no living cells. It is already dry, yet it must carry out a predetermined program regardless of whether or not it is alive.
How does this seedling's charming dance help us to develop human exoskeletons?
Many motion mechanics can be learned from nature and applied to robotics.
These soft-robotic devices, for example, are inspired by various insects' movement mechanisms. For example, this one is based on an inchworm that crawls around on the ground. When tension is applied, it bends to one side and then the other.
Is the gold leaf on your table there because it is a good electrical conductor?
Yes, carbon is the electrode in this robot [that you are looking at], and gold is the conductor that helps drive the charge.
In the future, if a person has difficulty with hand mobility, for example, could an application developed using this technology assist them in drinking or writing independently?
Yes, this is exactly where we are heading. At the moment, we have this material applied to traditional textiles, but the idea is to make this material into [a soft-robotic] fibers and weave different textiles from it. So, we return to folk attire and the fabric-making process. All weft and warp yarns serve a purpose, and in our intelligent textiles, each functional fiber may serve a purpose. By combining these fibers in different ways we can create different mechanisms of movement in the fabric.
This smart fabric – once you've managed to create it as a fiber – can then be used to weave on prehistoric looms?
We can create exoskeletons that resemble clothing, i.e. by first knitting soft-robotic fibers as a fabric.
Editor: Kristina Kersa