What could biology possibly have to teach engineers and designers?
We’ve recently been exploring a methodology called biomimicry that brings innovative solutions and sustainable design together in a way few other fields can.
Many people initially react to biomimicry – the science of mapping design challenges to the natural world to find innovative solutions – with skepticism. Recently a client laughed at the idea and called me a #$@%’n hippie. While this may be partially true, all you have to do is look at some of the most cutting-edge research coming out of universities around the world to find examples of high-tech materials, processes, and systems that wouldn’t exist without a study of nature.
My favorite aspect of biomimicry is that it always brings sustainability along for the ride. Nature just doesn’t do unsustainable. So even if you’re only in it for the innovative solution, you’re also guaranteed a more sustainable one. (There’s my inner hippie again, always trying to sneak in some sustainability.)
How Biomimetic Design Happens
It’s often hard for people to understand why biomimicry works. The key realization is that natural systems are trying to solve the same types of design challenges that we are. How often have you participated in a kickoff meeting where the design goals weren’t faster, stronger, lighter, sexier, and cheaper?
The natural world has been working with these constraints for much longer than we have and with more dire consequences. Bresslergroup has been around for 40+ years, a long time in the design world, but life has been around for 3.8 billion years!
And despite the 2 to 8 million species still around, 99.9% of all species that’ve ever existed have gone extinct. Those 99.9% are the “design strategies that didn’t work.” The remaining organisms must be doing something right – so let’s learn from them how to design better products.
I’ve compiled my three favorite case studies to demonstrate how biomimetic design can create products that are more agile, lightweight, and efficient:
Biomimicry For More Agile Products
There are so many cool examples of biomimetic design, but Whale Power might be my favorite. It came to be when Dr. Frank Fish, who coincidentally studies the biomechanics of swimming, walked by a sculpture of a humpback whale with bumps on its flippers’ leading edges. He was confused. Shouldn’t the bumps be on the trailing edge? But it turned out the sculptor was quite familiar with humpbacks and had correctly located the bumps, or “tubercles.”
Following extensive wind tunnel testing, Dr. Fish discovered that these tubercles reduced drag by 32%, increased lift by 8%, and increased the stall angle of an airfoil by 40%. He has gone on to commercialize this technology, first on wind turbine blades and then on other types of airfoils, including industrial fans.
Biomimicry For More Lightweight Products
Another example that hits closer to home given my interest in structural optimization is the field of evolutionary structural optimization (ESO). It turns out that nature has a lot to teach us in terms of light-weighting structures from cars and airplanes to bikes and backpacking equipment.
Trees and bones are great examples of similar but opposite approaches to optimal structural design. As trees grow and bend in the wind, their cellular growth is proportional to principal stress. They selectively add material to high stress areas. Bones do this as well but they also gradually remove material from low stress areas. Both of these processes will sound familiar to anyone already doing structural optimization, but the difference in the natural world is its extremely iterative nature.
When I’m manually optimizing a mechanical part, it might go through anywhere from five to fifteen revisions. But the natural world does this one cell at a time over countless versions. The result is a dramatically more efficient structure.
This highly iterative approach has been emulated in a number of FEA-based software solutions under the alternative title of “topology optimization.” We’ve recently been researching these tools for use on future projects.
One of the more promising packages for product designers is called Inspire, by solidThinking. In the simple simulation shown below, the Inspire solver went through 26 iterations in five minutes and resulted in a 50% weight savings over the starting point. Of course, the starting point was far from optimum to begin with. However, published results do typically show weight savings compared to manual optimization on the order of 20% to 40%. This particular technique could find application on many projects where clients are looking to use less material, thereby decreasing weight, lowering material and shipping cost, and decreasing the environmental impact.
The sustainability benefits of weight savings are particularly great in the transportation sector. My back of the envelope calculation shows that a 10% savings on the weight of my car would prevent the emission of 16,000 pounds of CO2 and save me $2,800 in gas money over the life of the vehicle.
Biomimicry for Zero-Waste Systems
A final example, and one that’s close to our hearts, involves brewing beer. The problem with brewing beer is the significant wastes in the form of spent grains (91% by weight are waste), grey water, heat, and CO2. In natural systems there is no such thing as waste. To date there are at least three breweries I know of using a circular economy-based model pioneered by the Zero Emission Research Initiative (ZERI). Under the version that is being constructed at the Wildwood Brewery in Stevensville, Montana, the spent grains are used as a substrate for organic mushroom farming, but it doesn’t stop there.
The mushrooms break down the cellulose in the grain, making it a more easily digested food for animals, in this case worms. Worms further digest the grains and themselves are used as feed for chickens and fish as well as a source of enzymatic cleaners for the brewery. At this point what’s left of the grains will be combined with other organic wastes and grey water from the brewing process in an anaerobic digester. There, bacteria break down the organic matter and generate methane which is burned for heat in the brewing process. In addition the digester produces nutrient-rich fertilizer that can be used to grow barley, hops and vegetables. There are four main ingredients that go into beer: grain, hops, water and yeast – and at the completion of this project all four will be supplied to varying degrees by the closed loop system. Along the way “waste” streams will have been converted into mushrooms, vegetables, fish, and poultry for sale in local markets.
This example is particularly inspiring because it involves not just emulating the form of a natural design but also the ecosystem-level interactions. There are many parallels to more product-oriented manufacturing systems in terms of recycling waste streams, improving efficiency, and lowering input costs.
All manufacturing processes generate waste in one form or another, whether it’s offcuts, injection molding runners, waste heat, spent chemicals etc. The key to improved efficiency is to find and incorporate other processes that need those byproducts as inputs.
My Biomimicry Pep Talk
One of the great things about biomimicry is that you can apply it to any type of product or system. (Read more fascinating case studies here and here.) A general way to think about biomimetic design is as a flexible innovation methodology.
It can be used as a brainstorm tool. When generating concept ideas, ask the question, “Where does nature do something similar”?
It can also be used as a research tool where you map your design constraints to an ecosystem with similar constraints. For example we’ve worked on a number of projects based on micro fluidics. There are entire arid and semiarid biomes where plants and animals have countless strategies for condensing, transporting, filtering, and managing water that can be sources of design ideas.
Whether you need a quick, simple idea or want to design an entire city, there are things to be learned from nature.
As designers and engineers it’s easy to fall back on design ideas and solutions that have worked well in the past. That experience is part of the value in hiring a firm with a long and diverse history. But there are plenty of problems for which broadening the solution space is exactly what we need. It can be challenging to step outside your comfort zone, but in the long run, truly innovative solutions will pay for themselves many times over. And if those solutions were inspired by nature, you’ll likely have lowered your costs, decreased waste, and improved your environmental footprint along the way.