Human's interest in sports is not recent and with the passage of time, those roots have grown deeper and stronger in such a way that today it's not only a physical activity anymore. Today, it has become our passion, profession and above all due to a constant increase in the challenge leading to the demand for new gears, it has become science and engineering. We are slightly familiar with some of those implemented technological advancements such as VAR (video assistant referee), hawk-eyed cameras for stadiums and in addition, some time back I wrote a technical article about the aerodynamics comparison between Brazuca and Telstar. However, most of the other directly connected technical features of engineering in sports are still in the dark, therefore, with an aim of spreading the knowledge of those advancements and to stretch the borders of this platform, this series would present easy-to-understand information for such scientific progress. In today’s topic, I shall demonstrate one of those applied engineering cases where the swimming experience of the athletes was enhanced.
Bio-mimetically Engineered Swimsuits
Nature is the main driving force:
In almost every aspect of human life, nature has always played a key role as most of the advancements that we witness today are majorly driven by our improved understanding of the natural elements and their governing forces. We mimic, amend and apply those parameters in order to reshape the outcome of our actions by the development of incredible tools. Such imitation of the systems and models when utilized to solve complex human challenges is termed as ‘biomimetics’ i.e. the mimicry of the designs found in nature, applied to the man-made products in order to artificially adopt the beneficial traits of other species/organisms. However, simply copying the designs found in nature is not enough, we need to understand the working mechanics, which I would explain here briefly.
As we all know that the most essential and at the same time irritating force in the world is called ‘frictional force’, which governs our lives in almost every positive/negative aspect. This force is the reason that our blood is confined within our veins, vehicles can apply brakes, heat generation is possible and in its absence, an object set in motion would float around forever from once bounce to another. The same entity (friction) causes injuries due to drag against a rough surface and most importantly drain energy for locomotion of objects in air, land, and water. If we, for example, decrease the resistance forces on an object in the water, we can simply swim faster but the dilemma is that we cannot control the forces, at least not yet.
We do not control forces but can modify surfaces:
However, thanks to the growing human intellect that we have a workaround that we can instead modify the surfaces in contact with water in order to fine-tune the effect of those forces in our advantage. That was the motivation behind the development of such swimsuits which could increase the speed of the swimmers by decreasing the drag force and buoyancy on the costume’s surface while increasing the thrust. As other friction-reducing methods such as greasing and oiling could not work efficiently with the fluidic environments such as water, an alternative approach was required. For this purpose, various observations were made on the aqua-life organisms and the solution was found in the skin of the most dangerous underwater species; ‘shark’. As we know, that this aqua predator has a significantly higher swim-speed even though its surface appears to be the same as any other fish. However, upon microscopic analysis, it was observed that the sharkskin had millions of small micro-sized structures called ‘denticles’.
Commercial adoption of the idea:
This led to the idea of creating similar structures on a swimsuit and the scientists from Harvard University successfully fabricated the first shark-skin mimicked swimwear. According to the explanation, those denticles could preserve small air cushions beneath them, forming air pockets while manipulating the buoyancy (water friction force) in their favor, thus helping the user swim with an exceptional pace. Soon after that the dream was converted into reality, the swimwear companies like ‘Speedo’ jumped in and grabbed the idea or we can rather say purchased and patented it. They produced the initial lot for the Olympic athletes and upon utilization in Olympics 2008, the swimmers broke world-records and in such huge numbers that a couple of years after the organizing committees had to ban the use of these high-tech swimsuits. The records were not canceled out but the costume regulations were changed which may mean that those swimsuit records might stand unbeaten for quite a while.
Controversy and availability:
Later, other scientists rejected the idea that those microstructures could be of any use and explained that the suits worn by the swimmers were skin-tight and do not provide any motion to the underlying body which is essential. They attempted to explain that the main factor which makes those microstructures effective in the case of shark is the presence of underlying fats in its body which moves along the direction of the small current in water causing the denticles to form vortexes. Whatever the case may be, the bio-mimetically patterned swimwears were still commercialized for public adoption and can still be found in the market.
That is all for today. I hope you understood the details and if you have any questions, do let me know. I shall try to explore my engineering knowledge to find some answers for you :)