AUTHOR: B E SAUNDERS, T E Hesselburg, J Zuma, T mBeki, J F V Vincent
TITLE: A Biomimetic Study into the design of a Robotic Attachment Mechanism using confocal microscopy and layered manufacture.
The use of Biological Principles finds application in design at micron size where little research has been conducted. Here the use of laboratory techniques in confocal microscopy and layered manufacture makes it possible to advance a theory on the design of an attachment mechanism modelled on a bee tarsus. The tarsus of a British common bee is used and represents a first design into a Universal attachment mechanism for small robots to attach to a wall and the development of micro-devices such as brain implants.
KEY WORDS: Biomimetics, Design, Confocal Microscopy, Layered Manufacture, Knowledge Transfer, Biological Principles
Industry is by its very Nature not green, as we invest energy to create a form of order that is opposed to the natural thermodynamic qualities of the environment. So to look to Biomimetics for a green technological solution is a naive fallacy and inhibiting to the very science of biomimetics where there are rules and principles to be obeyed but they are not limited to the green solutions others seem to propose.
It is about the principles of chemistry and physics, not the policy of a politician. It is about the modelling of a system, not the shaping of a world, which must be in other people’s hands. Nature is about chaos, not process, self-assembly without apparent direction or control system, and does not serve the human race. If a biomimetic solution is found to nuclear waste disposal from power plants, would you call it “green”? Or would you call it chemistry? Or physics? Is a mutation green?
This is a fundamental that is misunderstood by most writers as they adopt populist theories in order to sell, not knowing the true value of it as they ignore avenues open to research in other fields that must prove that biomimetics is useful to mankind but not secular. It does not hold that Intelligent Design is about Nature. It is about perception.
A new definition of Biomimetics could be “the modelling of biological processes”. This is a coverall for all biomimetic processes witnessed in the laboratory as well as organic processes due to Nature.
The Biomimetic studies of flight and adhesion can be considered as two different systems for analysis, as a dynamic and a static system respectively. To reverse engineer studying flight we must take Nature into the laboratory and study it in a manner that may be transferred to the manufacturing shop floor. This means a methodology needs to be developed that reliably establishes the trends of flight and its parameters.
It is simple to understand that robotic flight will require robotic control and the use of actuators. Once we understand the pattern of movement, we can model this through Simulink(c) to produce an integrated circuit that will do what we want i.e. produce the motions of flight. All we need therefore is a high speed projection of a bee in flight, digitising its wing flutter to mark changes in angle of attack and yawl etc.
Now that Hirt et al  have shown it possible to produce structures of the order of size and shape of real insect tarsii in copper, it should be possible to begin the inspection of the surface interactions between small hooks and their substrates.
The underlying hypothesis behind the exploration of the detail of papers  and  accepts the viability of using cladistic methods to arrive at a scenario where a structure that has survived the “evolutionary sieve” is selected, to quote Nicklaus et al , over the use of Linnaeus or other classification methods which can be seen as insignificantly better when it comes to evolutionary manifestations of properties and/or structures. In other words all evolutionary models are all imperfect and so it is that the solution must indeed be imperfect too if it is to reflect the true nature of the Natural World i.e. testing is necessary before any firm conclusions can be reached. The use of the hook is a not very interesting thing, relatively. But it is also the ideal way to start with the designing of micro-sized (~100micron) objects because of the over-hangs of the hooks, which are of the minimal complexities to test the programmer and they can be assembled into machine-like components for manufacture. Their origins are a little too old for one to understand their development since the designs are based in evolutionary theory, which is utilised in order to identify which structures are viable and of suitable length and strength to be of use in the manufacture of computer components to attach to PCB’s (printed circuit boards).
A UNIVERSAL FOOT FOR ATTACHMENT TO ALL SURFACES FOR A ROBOT
With respect to a Universal Foot it is impossible to measure its probability of fastening since there is a possibility that it may not hold the correct angle on the surface/substrate. That will be overcome with a hinge that will allow the foot to align with the ground according to its angle and not the angle of application. It therefore can be used by the military to develop further and so it is about to be since it has application to the frontier of technology and the use is yet to be completely foreseen, such as soft robotics, micro-robotics, biosensors, computer hardware, orthodontics and optical sensors through the use of copper which is a very known substance with qualities that have been researched and ascertained through its use as a strain gauge and other common applications.
It will be seen that there are a number of solutions to the problem of a Universal Foot and that means a test-rig will have to be devised such that it can measure the forces with which a hook attaches to a substrate and that is the way through to the end of the series such that each member of the group of probabilistic fasteners can be measured, of different biological materials as imaged in . In the meantime it is possible to make deductions such that a design can be arrived at that resembles a caterpillar yet makes use of the hook of the burdock and the range of movement that requires needful thinking so that it can be measured. Once this is done we have a product which can be commercialised. Part 2  contains the results of the experimentation to image cellulose and chitin and this will prove useful in the future when we consider a wide range of hooking and other mechanisms/devices since it will be in the interest of those continuing the study to know the difference between the two and whether they can use the data to make hooks that are biological such as those to attach to the stomach wall or the vessels of the heart since they bear cilia which makes them difficult to render in a stainless steel as with a stent. But when it is available it may be possible to make them from a biological material which does not dissolve such as the MIT device which, when swallowed, removes a watch battery from the stomach wall to avoid a ulcer forming there or to patch a wound, steered by magnetic fields and which is still in the experimental phase. It is made from pig’s sinew which is insoluble but which does not lend itself to electro-deposition of course so an alternative will need to be found. The electro-deposition of stainless steel has been investigated by Hasegawa et al  and it shows that an improvement has been made to the processing of an otherwise inert steel that does not corrode or “anodize” and it can be electro-deposited on copper. This will make the stainless steel coated copper relatively biologically inert.
To produce a study plan for the solving of one of Nature’s greatest questions: How does a bee stick to a wall?
Layered manufacturing device as described in 
Confocal microscope (single or two phase)
1. Examine a specimen of insect chitin under the confocal microscope, output in .tiff files.
2. Transfer output .tiffs to the layered manufacturing device to produce a sample of a reverse engineered tarsus as described in Figure  below.
3. Test the result for adhesion with a flat frictionless substrate and others.
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Figure 1: Images 1-30 are the sections of natural luminescence through a common bee tarsus using a single phase confocal microscope. (see )
For many years scientists have been studying the work done and methods of doing so in the animal world. The work being energy transfer and the methods, from walking to holding a stone as a hammer. It now has become possible to study the intimate details of the assembly of life and it is also becoming a useful aptitude to be able to make the correct decision with regards to design and this encompasses the system as well as the part itself which is being considered. So it becomes a necessary point to make that one can now physically reproduce to microns in accuracy and no longer is it necessary to stick to statistical methods of assessment and aspiration. Physical biology can now be measured at a micron level as can the performance of these structures, albeit in a metal. These metal structures have yet to be tested but their material composition shall add to the value of the design durability.
At a foundation has been a determined effort to move towards direct data transfer, from microscope image to layered manufacture, as it is called now. Because scaling effects exist, the non-Newtonian mechanical properties of the vast majority of hooked attachment mechanisms can only be mimicked and tested when manufactured at the same order of size.
The door is creaking open, upon the region of science and manufacturing technology called Microdesign. As never before the opportunity arises for manufacturing expansion into the realm of micron-sized structural designs that could benefit man through their use of their size. In the light of new developments into biomedical structures there is a need for stable materials at this scale to be used within biological systems.
The hook, as a shape of low-complexity, proved an excellent example to demonstrate the limits of current technology and its new abilities due to the work of Hirt et al . In terms of 3-D data collection via laser scanning, resolution of an overhang is impossible in C++ programming terms unless one moves the head of the layered manufacturing device in which case complex shapes can be reproduced. Surface modelling via Canny Edge Detection methods does not provide for holes or overhangs in the first instance.
The set of all Biological hooks in Nature can be divided along lines of material, structure and function. When considering shape and form one must consider it surprising that all biomaterial seem able to form hook shapes and do. At the smallest scale, near atomic level and in the region where self-assembly occurs, there must be incentive to form these shapes which is a directed response to the environment. It could be that these early shapes, these hooks, were in fact invented by Life itself as a form of camouflage with dual purpose and thereby were able to be used to vary Life without threatening it. For the first, the very first curve or hook shapes on earth must have occurred in the rock material of the surface and other parts.
A crude mapping system is available to us at any time, much like a parts manufacturer would catalogue a system of related parts. But this is not the purpose of the research, which is into micro-design of which the hook-shape forms a complex challenge.
Figure 2: This shows a design space for fasteners, without micro-fasteners included except in the form of gecko-feet and a macro-sized form of velcro (c). There must be a place for these new micro-fasteners that are being suggested, micro-designed after Natural attachments that rise into the empty space of high relative strength and high-reusability on the chart. A Universal Foot would have high adaptability and variable strength. 
This important work by Hirt et al has physical significance outside that of biomimetic applications. The output, in copper, has potential uses such as the brushes on micromachines.
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3. Saunders B. Biomimetic study of natural attachment mechanisms—imaging cellulose and Chitin part 2. J. Robot. Biomim. 2015;2:7. doi:10.1186/s40638-015-0032-9.
4. Saunders B., Microdesign using frictional, hooked, attachment mechanisms: a biomimetic study of natural attachment mechanisms—Part 3
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