One of the fundamental characteristics of additive manufacturing (AM) is that it allows us to 3D print complex geometries, much more complex than what other manufacturing technologies enable. Implicitly, the AM ecosystem also enables efficient iterative design – try something and then make a small change, if it works make some more changes, if not revert back. There is another ecosystem that enables this, though much more slowly: nature. The mechanism used in nature is mutations and evolution – survival of the fittest or the best to adapt. By its nature this mechanism takes generations and therefore happens slowly. With AM iterative design can be vastly expedited to the point where it becomes a revolution. Is this the only thing AM can borrow or adapt from nature? Let’s explore.
Layer by Layer
The intrinsic layer by layer construction of 3D printing is something we see in nature, in cocoons and nests for example. This video (would love to know attribution) shows a cocoon being built not from spinning threads but rather by systematic material deposition. Wasps and bees also employ this technique to build their nests/hives out of mud, or mush they create such as paper mush or beeswax (we’ll get back to hives in a minute). Of course, as in everything, in nature it is more painstaking and slow to build structures that would be created much faster with a 3D printer. The technique of applying mud by insects and birds is similar to how 3D printers build with concrete or ceramic paste. Compare the look and feel of the nest of a mud dauber (up top) also called an organ-pipe wasp and the barracks built by the US military in concrete with a 3D printer (below). The texture and look of them is surprisingly similar.
Optimization & Iteration
Thanks to the digital nature of AM and its ability to produce complex geometries, optimization algorithms can be applied to parts and products. Sometimes this process yields very strange looking parts that regardless of their unusual looks perform even better than plain looking parts. In other occasions we see that nature, through evolution, has already optimized the best way to perform a task. My colleague, Tessa Blokland, saw a great example of that at FormNext 2018: it is an optimized fluid intake duct 3D printed on an HP machine (below). The similarity to our own fluid (and food) intake mechanism is unmistakable. Of course, there are other uses for our tongue (in chewing for example), but still this optimization result is fascinating showing how sophisticated nature is.
Nature has been using iterations (in nature’s case called generations) for millions and millions of years in the process of evolution. Practically everything in nature has evolved iteratively. Naturally, AM enables highly efficient iterative design. This has been used by companies to apply various optimization techniques (and also to validate optimization algorithms) in their design. The image below, for example, shows iterations and optimizations of a BMW roof bracket.
Imitation and Adaptation
Imitation is the highest form of flattery, they say, and nature certainly deserves many compliments. It is wondrous how the fittest survive and it turns out that the fittest are those optimized for their tasks. One of the most prevalent geometries used in AM are lattice or mesh geometries. A popular one is the highly optimized hexagonal bee hive lattice – this is the optimal way to cover a large region with identical shapes while minimizing their boundaries. In nature, as in 3D printing, it exhibits optimal use of space, strength, and material efficiency that make it a popular and desirable choice. Even in nature, it isn’t just bees that have evolved to use it, other insects such as wasps and ants are also master hexagonal mesh builders. In FDM 3D printing the hex mesh is probably the most popular filler of solid shapes. However, in nature and in AM there isn’t just 1 solution to all problems and other meshes are used. The Urodid Moth (below – photo by Jeff Cremer), for example, uses a mesh pupa rather than a solid one. Why? this moth lives in the rain forest and so it must provide the rain downpour a way to quickly drain out of its cocoon to avoid drowning. The chrysalis inside turns into a moth which exits through the bottom “escape hatch”. Somewhat similarly, hollow powder printed items need to have draining holes as well, for the excess powder.
Caring is Caring
There is another way the AM ecosystem is looking at nature, especially recently. Since we care about nature, we take care of it by adopting sustainable processes and practices. Additive Manufacturing is inherently more sustainable than other manufacturing technologies because it creates very little waste. That is a big win but we can improve things even beyond that, though probably at a smaller magnitude. Every little bit counts! For example, while iterative design is a great way to evolve a product, today’s software solutions can simulate our design so we only 3D print it after several iterations, saving waste. Designs can be optimized to be lightweight so as to save on fuel consumption. At the end of life, some items can be recycled back into raw material for 3D printing reducing waste and improving reuse. Another way AM helps in reuse is in maintenance and repair. By using 3D printers to repair parts they can be used for longer periods and help sustain our beautiful nature just that little bit more.
I’m sure everyone in the AM ecosystem feels they are helping to make this planet a better place but we need to keep at it. A bit more here and a bit more there add up to significant impact which hopefully will mean we can leave a sustainable planet with its amazing nature to our children and grandchildren. It’s a good feeling to know that by pushing our business forward we are also advancing these noble goals.