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  • Writer's pictureNed Patton

Taking Cues from Mother Nature – Biological Analogs and Biomimicry

I have talked about this quite a bit in the past, but it has been a while, so I thought I would talk about it a bit again, and add in what is called “biomimicry”.  This is exactly what it sounds like – making a mimic of some of the things that Mother Nature got right a long time ago in our designs for new devices.  Things like how does a Venus Flytrap work, and how do redwood trees get water all the way from the ground up to the top of the tree – 300 feet (100 meters for those of you not in the US). 



I thought that I would start off with one of the most obvious ones.  And the fact that the Airbus wing is mostly composites makes this work for this newsletter.  As I have written a number of times, engineering design is commonly a product of smart engineers taking a long, hard look at how nature solved some of the complex problems that they face, and working out clever ways to mimic those solutions.  This is actually quite common in composites design which is why I’m going back to it this week.

There is a good article in Composites World about Biomimicry and drawing design cues from nature (https://www.compositesworld.com/kc/sustainability/articles/drawing-design-cues-from-nature-designing-for-biomimetic-composites-part-1).  One point that the article makes is that nature forms non-isotropic or anisotropic (different properties in different directions) structures as a matter of course.  There are in fact very few completely isotropic natural materials or structures found in nature.  Nearly all if not all are anisotropic.  This is of course the beauty of composites, and as I have said on several occasions, composites Achilles Heel.  There are an infinite number of ways to solve a structural problem using composites, so what do you pick. 

In the case of what nature has come up with, the answer to that is easy.  Those that are successful survive to bear new copies of their species whereas those that are not successful don’t make it that far.  Darwin of course taught us that.  And, of course, Engineers have at most a few weeks to come up with an answer to a problem whereas Mother Nature has the gift of time (millions of years in fact) to get it right.  So, man has been smart enough to take a good hard look at what is available that either solves the problem at hand or one close enough to it that whatever nature came up with can be adapted pretty well. 



Borrowed from Composites World (1)

Mother Nature goes even a bit further than what humans have been able to create in our organic composite structures.  The pic above from the Composites World article cited above show hierarchical structures – structures made up from very simple one dimensional organic molecules (like collagen for animals, or cellulose in plants) with other things that enhance particular properties of these one dimensional molecules tied together with other things that bind and enhance properties, in bundles or flat plates, or even lamellar structures (composed of layers of different stuff like the crab carapace).  Even silk is a composite structure of fibrils encased in a sheath.  And that fiber is made by what some would think is just a worm that transforms into a moth.  But that worm makes something that is prized all over the world.  Fine Asian silks bring a pretty penny in the fashion world.


What about biological analogs in all of this, where do they fit in and what composite structures have been created specifically as biological analogs?  One that I found fascinating is the creation of artificial muscles – especially the one that is beating in your chest right now.  This pic is from an article in “Nature Communications” from the journal Nature.  What these researchers were able to do was to create bio-inspired elastomeric (rubbery) composites with mechanical and electrical properties that actually make them piezoelectric.  They will contract in one direction when a small electrical current is applied to them.  And it appears that they got the mechanical properties in the two directions that they tested very close to what is seen in heart muscle.  They used a very flexible 3D polyimide structure (squishy clear stuff in the pic) coupled with a crumpled conductive surface to produce contraction in one direction – just like a muscle.  This is a great example of both biomimicry and biological analog in the same structure.  It is these sorts of innovations in the composite materials industry that make it clear that we are on the right path.

One more example that I want to provide here is using concepts from mother nature as ideas for consumer products where both comfort and safety of the user are paramount in the design of the material.  What I’m talking about is the interior padding on your car door.  That padding has to be both strong and soft/flexible at the same time.  It has to hold up to continuous abuse over long periods of time.  None of us really take great care when it comes to the interior materials in our cars and light trucks.  We don’t want them to rattle or make noise, but shoving a back door shut just to squeeze in that last piece of luggage on the way to the airport or even on a long car trip to see grandma is going to happen to all of us.


It's the pic on the right that I’m talking about here.  The little orange critter at the bottom of the right hand pic is the red-eared slider (yes, a turtle), and that structure mimics the shell of this critter.  These little critters, at least according to Wikipedia, are the world’s most commonly traded reptile, so there is probably one at your local pet store waiting to come home and be your friend (just kidding folks).  This structure is stronger as well as lighter weight than your typical interior door panel and it is safer as well because it has a spongy interior that absorbs impacts well. 

That’s about it for this week.  And again, this newsletter was written on my keyboard using my fingers and my brain, not AI.  And, finally, I need to remind everyone that my book is ready for anyone to purchase.  The best place to get one is to go to my website and buy one.  I will send you a signed copy for the same price you would get charged on Amazon, except that I charge $8 shipping.  Anyway, here’s the link to get your signed copy:  https://www.nedpatton.com/product-page/the-string-and-glue-of-our-world-signed-copy.  And as usual, here’s a picture of the book, for those of you just tuning in.


(1)    Hierarchical structures of bone, nacre, a crab carapace, bamboo, tendon and silk. Photo Credit: Reprinted from Composites Science and Technology, Vol 214, 2021, 108970, Yuli Chen,Yong Ma,Qifang Yin,Fei Pan,Chaojie Cui, ZuoqiZhang, Bin Liu, “Advances in mechanics of hierarchical composite materials,” p. 2. Copyright 2007

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Erik Walters
Erik Walters
Mar 26
Rated 5 out of 5 stars.

Well if Mother doesn't know best then who will? These are great articles with tons of insight that more people need to know about.

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