Conclusion

Hey fellow readers/followers!

It has been a great semester through the module of Engineering and Biomimetics!

Time flies and this would be our very last post.

From the beginning of the journey where we have adopted our 3 musketeers to the end of discovering an idea that can be done via critical thinking and observation on the daily life of our little friends.

The suction power of the Pleco fish is tremendously strong due to the microvilli on the suction area which allows them to adhere onto almost any surface while being strongly attached. This feature has allowed us to think of a flexible suction cup that can be attached on any kind of surface be it wet, dry, even or uneven. This flexible suction cup if realised would be really helpful in terms of underwater discovery where it is hard to retrieve the items underwater where cranes and hooks are usually used. Furthermore, the team has even pursued to draw the structure of the flexible suction cup using Solidworks although it is not our forte as Chemical Engineering students.

From a small Pleco fish, its life has brought us such inspiration that may be realised in the future that is beneficial to humankind. Of course, the idea that the group came up with is just an idea and much research has to be done in order for this to be realised.

After weeks of adopting the Pleco fish, here is a picture to show how much they have grown.

Look at how big they are now! 

We do hope that this blog has provided more insight on Pleco fish. We wanna thank all readers/followers who has been following our posts throughout this module. Truly grateful for all your support. 

Signing off,

Sie Kian, Sie Kiong, Ivan and Pak Kee

Self Reflection

Sie Kian says.....

The experience in working on the Biomimetic Project was challenging and fun, but most importantly it was an eye opening project which I came to appreciate. First of all, I have the responsibility to the adopted Pleco fish such as feeding it and changing the water every three to four days. I have read numerous webpage regarding the Pleco fish to better understand their habitat so as to provide them with the suitable living environment and diet. The responsibility that I have bared during this project make me realise that nature do known best and able to solve problems without compromising the environment. 

Regarding the blog creation, I personally felt that it was difference approach towards my learning style. In order to create a meaningful blog with adequate information, I have done many comprehensive reading regarding the biological aspect of the Pleco fish as well as the biomimicry on the Plecos. I am not a typical person who love reading a lot, but learning via blog creation have encourage me so. I and the group have put a significant amount of time and effort on the blog, which we personally felt proud of it.

The most fascinating and admiring biomimicry on our blog would be the ability of the plecostomus species to attach themselves to almost any kind of surfaces, regardless surfaces which are both wet and uneven or even underwater. This is something current technology could not achieve. Therefore, after studying the physics and biology behind this possibility, the group have decided to mimic the feature of the plecostomus species which enables them to accomplish such feats. Our bio inspiration involved the improvement to current suction cups/pads. By incorporating the microscopic hair feature on the surface edge of the suction cups/pads, attaching to wet and even surface could be made possible. In short, these microscopic hair add friction to the cups/pads to prevent slips while at the same time preventing water from slipping in the vacuum space, therefore maintaining the suction capability.

 Lastly, working in a group have make the completion of the blog possible. Each members contributed a significant effort to the blog. The bio inspiration would not be possible without constructive brainstorming. My greatest contribution in the project with be taking care of the fish, providing the literature reviews on the Pleco and also using SolidWorks to draw the mimicked microscopic hair on the surface of the suction cups/pads. It was a real challenge for a CE discipline to do so with so limited knowledge on the software, but all challenges are accepted and the prototype model was produced.

Sie Kiong says....

This entire 14 weeks of studying the biomimicry of the Pleco fish along with 3 of my group members has been an amazing journey. At the beginning of this module, our group encountered some difficult decision in deciding the type of creature that we would want to adopt. But after much serious discussion, we finally came to an agreement to adopt  Pleco fish as these amazing creatures are actually natural survival of nature.

Throughout this module, I have been keeping close attention on studying 3 of our adopted Pleco fish in terms of their living pattern, eating habits etc. I find that the Pleco fish are friendly when they are juvenile but will grow to become aggressive in terms of their territory as the age. But, having lived together for the past 3 months, these Pleco have learned to share their territory with each other, which is a big relief for me because the Pleco will actually fight to the death  just to occupy a territory. I can say that after taking care of these Pleco, they really love to eat cucumber that we bought instead of the sinking food. If anyone has Pleco at home, I would suggest you to feed them cucumber as well as it actually provided them with lots of nutrients.

In this group, my contributions are mainly on writing the literature review on the Pleco fish which most of the researcher actually refer them as the more common term of suckermouth fish or armoured catfish. I studied on the scale of the fish which is actually very different from other fish as it is very tough which protects them from predatory as deadly as piranha. I am amazed that the scale of the Pleco is so tough that it could fracture the piranha's teeth when they tried to bite it. This was initially one of our idea for the bio-inspiration for the blog creation which is to create something that is tough but flexible at the same time. But, we are also amazed by the suckermouth of the Pleco which can perform suction on a wet and uneven surface, that which inspired our novel industrial application for the underwater crane to lift a heavy sunken object at the seabed. Besides that, I have also spent some extra time to write about some fun facts of the Pleco in our blog, have fun reading them!

To conclude my personal reflection to this blog, I truly felt that this module lead me to view engineering in a different point of view whereby we could actually look to nature for inspiration and idea when it comes to design and solving and engineering challenges. Up to date, there are countless of engineering designs that are inspired by nature that we aren't aware of. I was surprised to learn that many of our daily applications actually came from nature itself such as the Velco, tapes, swimsuits and so much more. This course makes me appreciate the teachings from nature (like seriously), it also makes me realised that we aren't treating nature fairly where a lot of us still pollute the environment and over urbanisation which cuts down the natural habitat for many creatures.

Lastly, I would like to show my gratitude to my group members for their efforts in this blog creation. I think in a way, this blog creation also brings us closer together as friends. As a final year student, I feel that taking this module does provide me with something different than the typical engineering modules that I have taken for the past 4 years here at Taylor's.

Ivan says....

In the beginning of this module, we find it hard to decide on which life creation to adopt. We finally came to a decision of adopting Pleco fish with a curious mindset that what the Pleco fish can inspire us. Throughout the journey, it is a great sight to see the growth of the Pleco fish. Their growth has shown that they are able to adapt in a different environment from before. Their growth period has inspired us to study on how they are able to attach on the surface of the little aquarium and how they are able to even eat upside down.

The study done on the mouth of the Pleco has shown that there is actually microvilli on the suction area which makes the Pleco fish to be able to adhere onto various surfaces. This has inspired us to think of how the current underwater crane has the problem where they have put time and effort into finding the best way of obtaining the object from the sea bed. The application that we have thought of may be able to solve this problem where the suction cup is able to obtain objects regardless of the surface condition.

Working with the other 3 members have been a pleasure. Starting the blog and being one of the editors has made me become closer with the others. Although sometimes lazy to do so, other members have consistently pushed me on to make the blog a success. Group discussions are always done in an orderly manner and I am glad that I have 3 great group members. Since this is the last semester of my engineering degree (assuming that I pass this last semester), I think that this blog creation has really enhance my friendship with the other group members. Cheers to all :)

Pak Kee says...

It has been an enjoyable ride of 14 weeks being continuously inspired by mother nature and her ability in overcoming complex challenges. The adoption of Plecostomus fish, which was initially a random idea has actually opened my eyes in the potential of ideas that can be derived from it. Although 14 weeks might sound like a short span of time, but we have been able to witness their versatility in growing away from their natural habitat. The interesting thing about Pleco. fish in its ability to sticking on wet and slippery surface which has motivated us in studying this feature.

The presence of tiny hairs around the lining of Pleco. fish mouth as well as its flexibility rendering them to adhere to uneven surfaces with ease, which leads to the conceive of idea in which the mimicked suction mouth could be used to replace the unsteady crane hook. The ability of the suction cup in maintaining its suction power under conditions like high current or wet surfaces emerged as the most valuable innovation aspect in the application of underwater crane.

Being able to contribute to the group through extensive readings of literature and reviewing them in the blog has been a rewarding experience, specifically the anatomy of Plecos. fish. Besides, getting to research on the weakness of "crane-hook" or shackling of underwater payload has indeed inspired me and my group which lead to the invention of our novel product. Overall it has been a pleasure experience to be able to work with such attentive and motivating group mates. Certainly, I never knew writing blog could be that enjoyable and I hope I discovered it earlier!

Components of Flexible Suction Cup

Suction Cup Prototype - not to actual scale

The figure above shows the proposed flexible suction cup to be applied on wet/dry/even/uneven surfaces. The basic material to construct this flexible suction cup is silicon. At the mouth of the flexible suction, there is a layer of nano-sized silicon-made hair which mimics the microvilli on the suction area of the Pleco fish or the Cling fish. Silicon is the chosen material to construct this device due to its high adaptability towards high temperature as well as low cost. In addition, using silicon as the construction material makes it more flexible to adapt to various conditions. The usage of silicon makes the suction cup to be more resistant to wear and tear which makes it to have a longer lifetime. The large surface area of the suction cup allows it to have a better contact area for better suction power. It is believed by the team that the proposed design would become a huge difference in providing high suction power for various applications on wet/dry/even/uneven surfaces.

Currently, our team proposed to use suction force to lift sunken object at the sea bed such part from crashed aircraft, ship or submarine during the war time. The proposal of suction would replace the usage of hooks in the current underwater crane which have small surface area at the point of attachment. On the other hand, the new crane proposed by our team will provide a larger surface area which can distribute the stress of the load instead of focusing the load at a single point like the case of the hook.

Real Life Application of Flexible Suction Cup

Underwater Crane

            The study of marine environment, specifically the deep sea requires precise placement of considerably large and delicate instruments, for instance hydrophone or pressure pickup array on the sea bed in a particular geometric pattern. Such operations usually involve the usage of a surface craft which is equipped with a crane, working in conjunction with divers facilitating the operations on the sea bottom. Challenges such as high current condition or high sea state pose serious problems to such operations, specifically when it involves the shackling or hook-and-release of the payload. The hooks must also be bright colour or fluorescent so that the operator can identify the component to be shackled correctly under the poor artificial lighting condition underwater.

            Another problem arises from the usage of hook is the need to into consideration of external effects such as wind and choppy waters besides the crane’s movement in order to maintain the correct alignment. To maintain an upright alignment all the time during lifting operations requires sophisticated tools, for instance Cargotec uses the ARC tool which consists of an electrically driven power swivel fitted with a frequency control system coupling with a motion reference sensor. The utilization of ARC tool is claimed to cut down handling times up to 30% during operations while undoubtedly shoot up the capital cost.

Figure 1: Underwater crane with a rubber flotation bladder in a protective clothing, controlled bleed-off valve and compressed-air supply.

References:

   http://www.liftingsafety.co.uk/category/rov-rigging-equipment-1242.html

  http://www.cranestodaymagazine.com/features/under-the-hook-update/

  http://www.aslo.org/lo/toc/vol_9/issue_1/0150.pdf

Application Inspired by Suction Mouth of Plescostomus.

            By drawing inspiration from the operating mechanism of the suction disc of a Cling fish, a flexible suction cup is conceived and designed, which is superior to conventional suction cup in its ability to maintain the suction, even at wet and slimy surfaces. Besides, the suction cup performs well in different types of surface, be it uniform or uneven. The bio-inspired suction cup come forth as a prospective replacement for the shackle or hook of underwater crane. The ability to maintain suction force on a wet surface in the presence of considerably high current ensures a tight grip on the underwater load. By identifying several spots as the lifting points of the load prior to the lifting operations, the load located underwater can thus be lifted steadily with ease, rule out the need of cutting-edge motion-sensor tools.

Suction Cup

What is a suction cup?

A suction cup is basically a device that adheres onto a surface for various applications. Some of the various applications of suction cups are:
1)To adhere objects onto tile walls
2)To move glass panes
3)Nerf darts
4)Toilet plungers

Problem of a suction cup:

Currently, suction cups that are available in the market can only adhere to flat, clean and dry surfaces. When suction cups are applied onto wet/slimy/ rough surfaces the suction power is almost insignificant. Suction cups depends on the pressure difference inside the suction cup and the atmospheric pressure. When suction cups are pressed, the volume of air inside the cup reduces, thus reducing pressure. The higher atmospheric pressure pushes the cup inwards, causing them to adhere to surfaces. On rough surface, the surface is uneven and there is air leakages causing the pressure to be insufficient for proper suction power.

Figure 1. Suction on uneven surface

Possible solution inspired by Pleco:

Figure 2. Microvilli producing friction on uneven surfaces

Pleco is able to adhere to various surfaces as they have microscopic ‘hair’ or microvilli on their specific suction region. These flexible microvilli produces friction onto uneven surfaces providing more grip onto the surfaces. In addition, these microvilli blocks the leaking air pathway which produces the pressure difference more efficiently. Thus, this enables the Pleco to attach onto various surfaces. 

The Biomimicry Design Spiral

In this blog, we make use part of the biomimicry design spiral for the bio-inspiration of the Pleco fish. The design is a step-by-step for turning nature’s strategy into innovative and sustainable design solution. The spiral has 6 different steps arrange in the sequence of identify, translate, discover, abstract, emulate and evaluate.

In this blog creation, we demonstrate on two of the stages of the biomimicry spiral in our novel industrial application, which is the identify and translate stage.

Figure 1. Biomimicry Design Spiral

Identify

In this stage, the goal is to identify the basic functions the design need to perform. The approach is to list down all the possible or required the functions the design need to do.

For our industrial suction device for an underwater crank, the main function is obviously to perform suction. To be more specific, the suction has to be able to sustain under wet conditions which were what we are able to observe from the Pleco fish for the past 12 weeks. As mentioned in the Literature Review, the suckermouth of the Pleco fish and also the Clingfish actually consists of microscopic hair called the “knobs” that actually provided a friction with the attached surface where these hairs actually prevented water from pushing into the suction region which would have fail the suction function.

Translate

In this stage, translate is to convert the desired function of the design into words or terms that makes sense in the biological world. For the function of suction in our bio-inspired design, the function is translated as ‘attach to surface temporarily’. The suction was achieved via the pressure difference between the suction mouth and the surface whereby the vaccum condition on the bottom side of the suction cup is subjected to higher external pressure that kept pushing onto the cup that allow them to be continuously attached to each other. For the suction under water, the additional feature that prevent water from pushing into the sides of the suction cup is by lining the mouth of the suction cups with microscopic hairs that creates friction with the attached surface that form a barrier to prevent water from entering.

Some AMAZING facts on Pleco

Pleco, Plecostomus, common algae sucker, is the algae eater fish commonly found in fish tanks at home. They are silent workers. They never disturb any other fish and they are good. Several things we did not know about this amazing fish which we think you need to know. Pleco can survive without water longer than any other fish can. BUT Ttis does not mean that you try this out by taking the pleco out of your aquarium. Hypostomus Plecostomus are able to breathe atmospheric oxygen. If the air pump on your tank ever fails, your pleco will survive for some time because they are able to shoot to the surface and take a gulp of air.

FACT#1 : Plecos surviving without water for 4 HOURS!

The owner of the video below actually describes that his beloved pleco has survived without water for 4 hours! Check out the video!

Fact#2: They love sucking!

Put your hand into the aquarium and they will eventually just suck on your hand just like their kissing you!

Fact#3: They are tough fellas.

Yes! Even Piranhas are scared of them! Remember to not make your pleco angry!

Fact#4: They eat cucumber.

Look at the pleco in the video below! So cute! 

Suckermouth of Plecostomus Could Inspired Better Suction Devices (Bio-inspiration Example 2)

We observed that the Plecostomus was able to perform suction even under wet environment as we seen them in the aquarium. Or they can even suck on a rock full of slimy algae. This gives us an inspiration on how such action could benefit the human race. Having said that, researcher at University of Washinton's Friday Harbour Laboratories studied on the Northern clingfish and observed that this clingfish was able to produce high suction forces that can support up to 150 times their own body weight even under wet and slimy surfaces. This is something that even the current suction device cannot do. This sparked the idea that if the biomechanics of the clingfish or even the Plecostomus could be mimicked, it would be beneficial for the application of medical devices for surgical operations. Unlike the Plecostomus, the bellies of the clingfish provided the suction instead of their mouth, but either way both of the feature still allowed to be attached to a wet and slimy surface. The belly of the clingfish is like a rim of disc covered with a microscopic hair-like structure which created a layered effect that allowed them to attached to surfaces. On top of that, their disc-shaped bellies are also elastic where they can attach to uneven surfaces. 

The bio-inspiration from this creature is to be able to stick surgical devices into the patient's organs or tissue without harming them. The ability to retract delicate tissue without clamping them is what doctors desired in the laparoscopic surgery.....and the suction disc of the clingfish could lead a new way to manipulate organs without any risk of puncture. Besides for medical field, researchers also wants to develop a new type of tagging tool based on this suction feature to tag onto the body of animals such as whales without puncturing their skin with darts. Other than that, this type of development can also be very useful for shower caddy that uses suction cups as the bathroom is mostly wet all the time.

Figure 1 showed the underside of the clingfish. As seen in the figure, the disc-shaped belly of the clingfish looks very much similar to the suckermouth of the Plecostomus (see the comparison in Figure 2), which is why we believe they could also inspire for better suction devices besides the clingfish. We would also like to share a mind-blowing video on the suction power of the clingfish, you have to see it to believe it.

Figure 1. Underside of the clingfish - the disc-shaped belly

Figure 2. Comparison of the belly of clingfish and suckermouth of Plecostomus

Additional information that might interest you too :)

In addition to that, the Plecotomus was also able to perform suction attachment and respiration simultaneously. The idea of performing suction and respiration at the same time seems contradictory to scientist because the combination of both actions would result in leakage of air from the mouth. Fascinated by such observation, researcher Tom Geerinkx and his team research onto how is was possible for the Plecostomus to perform such paradoxal activity. The research data from Tom and his team found that the muscle oral valve actively separates the post-valvular buccal cavity from the pre-valvular sucker cavity. As such, the change in volume of the pre-valvular cavity are opposed to those of the post-valvular cavity, and this assures the suction function even during exhalation.


Reference

http://www.washington.edu/news/2015/05/04/puget-sounds-clingfish-could-inspire-better-medical-devices-whale-tags/

https://www.researchgate.net/publication/50269275_Suckermouth_armored_catfish_resolve_the_paradox_of_simultaneous_respiration_and_suction_attachment_A_kinematic_study_of_Pterygoplichtys_disjunctivus

Teeth of Plecostomus

     One of the species of the Plecostomus family, Plecostomus cordovae was examined by Theodore H., focusing on the needle-like teeth of pleco fish. The teeth of Plecostomus cordovae are uniform tubes of dentine which contains no enamel, flattened at the tip. The entire set of teeth in each dentary and premaxilla lies in a deep trough in the bone while each tooth attaches by a movable joint just under the overhanging rim of the trough when the tooth is developed completely, as shown in Figure 1.

i., integument of mouth; p.m., premaxilla; t., tooth.

Figure 1: (Left) Ventral aspect of head of Plecostomus cordovae; (Right) Cross-section of premaxilla of Plecostomus cordovae showing development of series of teeth.

     The teeth are piled in vertical series within the jaw, in which the teeth at the bottom being buds in the first stage of development, and those toward the exterior growing progressively more complete and more angular until the last and oldest in the series emerges ready for use. The teeth that break off are replaced by the one below. The dentine is covered by two layers of columnar cells, one outside and another inside the tooth as shown in figure 2. The columnar layer within continues down to the bottom of each papilla and up the adjacent surface of the overlying cap during the earlier stages of the tooth papilla. These layers appear to be identical in the papilla and in the surrounding cap, which suggests that both layers contribute to the deposit of the tooth. It is worth to note that the increase in thickness at the tip is due to the lengthening of individual cells instead of the multiplication of layers.

           

     For more fully developed teeth, the cells within the dentine column become nearly cut off from those outside, as the need to carry materials to the tooth must exist as well as the observed groups of erythrocytes. A capillary passes close to the base of each tooth while sending a loop up into it. Distally the dentine within the tip is transparent, thin and filled with minute canals crossing it as many different angles.

     A series of zones exists along the face of the cavity in which the teeth arise, from bottom to the top. Narrow and nearly straight tip of the teeth formed in the bottom zone; the first segment of the shaft formed in the second zone, preceded by an angle; another segment marked by an opposite bend in the third zone and the final rounded base for articulation with the bone when the tooth is in position for use in the fourth zone. Hence, the growing teeth push those above gradually outward from the bottom of the trough; different effects occur as they come to different levels. Although their nature and factor are unknown, the effects are probably due to a sequence of changes in the secreting tissues. The complete tooth is a lifeless shell as the tissues become less compact within the teeth, eventually shrink away, leaving large gaps and scattered group of cells.

c., columnar cells; cap., capillary; d., dentine; e., erythrocytes

Figure 2: Microscopic section of earliest stages in tooth development of Plecostomus cordovae

Our NEXT POST discussed on how the SUCTION of the Plecostomus' mouth INSPIRED better MEDICAL DEVICES!!!

Reference

http://www.jstor.org/stable/1436721?seq=1#page_scan_tab_contents

Current Bio-inspiration from Fish Skin - Body Armour (Bio-inspiration Example 1)

In the previous post talked about the tough skin of the Pleco that served as a protection from predatory attack. Today’s post we talked about how the fish skin have inspired humanity.

Scientists at MIT and Technion-Israel Institute of Technology have been developing body armour for that was inspired by the fish skin. The newly developed body armour based on the fish skin could lead to new flexible materials for a uniform that can withstand bullets and knives piercing.

Unfortunately, this invention was not inspired by the strong dermal plates of the Pleco, but was inspired by another freshwater fish called the Arapaima Gigas that also exhibit a tough armour skin besides the Pleco. The researchers has observed that the skin of the Arapaima Gigas is so tough that it could protect them from piranha bite. Although though, scientist found that the scales of the Arapaima Gigas is also flexible as they spread the stress created by the piranha’s teeth by flexing and twisting.

Thus, this observation from the Arapaima Gigas gives scientist the idea to develop a tough but flexible body armour for the military as well as security forces to replace the current armour that is heavy.  Scientist, Professor Stephan Rudykh found out that the skin of the Arapaima Gigas consists of the tough outer layer that provides protection and the inner soft elastic layer kept the skin flexible. This is similar to that of the Pleco as discussed in the previous post.

In this development, the flexibility and strength are always the competing against each other. While the strength increases, it always leads to lower flexibility. But Professor Stephan found that they could increase the strength of the armour by 40 times while only reducing the flexibility by 5 times. This was achieved by positioning the artificial hard plastic scale at a certain angle. Right now, the challenge is to develop the right material. But nevertheless, this development is still feasible.

3D printed fish scale - inspiration fro new body armour

Artificial Human Skin-Tissue Engineering

Tissue engineering is another similar field of interest in organism’s skin biomimicry. The study organism skins originate from the field biomaterial. Among the all studies carried out, the most significant and impactful application would be tissue engineering. Countless research and time were dedicated to study the biology of human skins. A unique ability of the human and animal cells which was self-regeneration sparks the interest of mankind to study this unique feature. Throughout the history of tissue engineering, experiments have been conducted to growing cells outside a living organism (in vitro). The aim of tissue engineering was to resort, maintain or even improve the tissue functions that are defective and lost or destroyed due to diseases and accidents. After numerous research cell biology, biomaterial science, imaging and characterization of surface and cell interaction, artificial human skin was developed. This artificial skin, better known as scaffolds are three dimensional porous solid biomaterials designed to perform some of the functions of the human skin. These functions are such as cell-biomaterial interaction, cell adhesion, transport of gases, nutrients and regulatory functions to allow cell survival. The most significant function of the scaffolds are to provoke minimal degree of inflammation and toxicity to the host body. The future approach in tissue engineering is to develop artificial skins with self-healing properties as well as easier adaptation on patients.

Reference

http://www.dailymail.co.uk/sciencetech/article-3029185/The-body-armour-inspired-FISH-scales-Material-lead-bulletproof-uniforms.html

Dhandayuthapani, B. et al., 2011. Polymeric Scaffolds in Tissue Engineering Application: A Review. International Journal of Polymer Science, 2011, pp.1–19. Available at: http://www.hindawi.com/journals/ijps/2011/290602/ 

National Institute of Biomedical Imaging and Bioengineering, 2016, Tissue Engineering and Regenerative Medicine Available at: https://www.nibib.nih.gov/science-education/science-topics/tissue-engineering-and-regenerative-medicine.