Biomimicry

Question 1

What is biomimicry?

Answer 1

Addresses bioengineering, to develop new devices and biomaterials
Essentially machines, materials, fabrics or robots that emulate certain features of living creatures
Purpose is to learn optimal designs from evolutionary selection for incorporation into new devices or materials
Old practices with new names and applications

Question 2

What does inspiration from living organisms aim to do for new ideas?

Answer 2

Aim to improve efficiency, performance and economy of vehicles, tools or materials, and also for novel inventions
Derived from industrial biotechnology, but novel developments applied to other areas such as medical or environmental

Question 3

What are the main areas of biomimicry?

Answer 3

Robotics: Movement and sensing- flexibility, hovering etc
Fabrics and materials- strength, flexibility, camouflage etc

Question 4

Why do we want more robots?

Answer 4

Humans always want better, faster, stronger, bigger/smaller, more efficient
Danger- disaster zones need robust devices capable of moving over inaccessible terrain
Logistics- autonomous vehicles needed for defence/humanitarian purposes
Environmental solutions- quieter/more efficient renewables, detection, bioremediation

Question 5

What is an example of biomimicry?

Answer 5

Invertebrate diggers
Jack knife clam: an expert burrower
Energy efficiency: expended energy
1 clam could travel >0.5km through soil on energy stored in 1 AA battery
Mechanical diggers modelled on Jack knife clam

Question 6

What are the key elements of the Jack knife clam?

Answer 6

Burrowing movement: animal initially extends foot before raising valves
Shell valves contract shell rapidly, inflating foot with haemolymph from body, before clam pulls on anchored foot to drag body into soil, although burrowing distance is still greater than expected
Crucial part of technique: substrate liquidization

Question 7

Why is substrate liquidization a crucial part of the Jack knife clams burrowing movement?

Answer 7

Shell contraction relieves substrate pressure, water moves towards body, which fluidizes substrate particles
Fluidization reduces drag, clam moves downwards after which surrounding particles revert into place and resolidify. Movement through fluidized particles takes minimal energy compared with static particulate substrates

Question 8

What are badgers and anteaters?

Answer 8

Expert excavators
Problem: construction devices need better efficiency and resilience to wear and tear

Question 9

How are badgers and anteaters used for biomimicry?

Answer 9

Claws subjected to 3D scanning to create a point cloud model, which establishes shapes and allows curves to be copied for design
Paw and claw curves of the two species can be integrated to maximise design features

Question 10

What are the claws from badgers and anteaters?

Answer 10

Comparisons made of criteria including the stress and total deformation formed on the bucket itself, the excavation equipment and the excavated soil
Bucket tooth model identified showing 40% less stress on bucket itself, 17% greater stress on the soil

Question 11

Why build a robofish?

Answer 11

The fish use micro-electrode arrays to sense contaminants
Can detect contaminants
Has changeable chemical sensor for other contaminants
Uses AI to identify source of pollution
A useful tool in shallow waters with high level of toxic contaminants

Question 12

How can different fish species be used for biomimicry?

Answer 12

Improved maneuverability
Stealth
Power and stability- highly flexible pectoral fins give upward and forward force
Prevents yawning and twisting by working in concert with caudal and anal fins
Robotic mimicry to improve submarine efficiency in water

Question 13

How can a real ray be used for biomimicry?

Answer 13

Cyborg ray
Stealth (undulating motion)
Cyborg ray gold skeleton overlaid with a flexible polymer

Question 14

What are the properties of an artificial ray?

Answer 14

Muscle constitutes genetically engineered at cardiomyocytes, electrically coupled with gap junctions
Monocytes express light-sensitive ion channel ChR2
Light stimulus directed at the front of the cyborg triggers propagation of an action potential modulated by the gap junctions between muscle cells

Question 15

What is the robojelly?

Answer 15

Runs on hydrogen-oxygen energy source
Framework made from multi-walled C nanotubes on surface of Ni-Ti shape memory alloy
Sensitive pressure sensors inform on depth
Has light sensors to detect location of obstacles, inclu. other robo-jellies

Question 16

What is the robolob?

Answer 16

The mechanical lobster
Lobster body is adept at scrambling over rocks, through crevices in coastal shallows
Robust to damage and has neural network which allows it to sense prey
Robolob is legged ambulatory vehicle intended for autonomous remote sensing operations in rivers and/or or the littoral zone ocean bottom, especially for detecting mines

Question 17

What is the octobot?

Answer 17

1st entirely soft material autonomous robot
Inspired by octopus movements (no skeleton)
Made from silicone polymers and 3D printing
2cm length: driven by H2O2 for fuel, energy generated when exposed to platinum
Self controlled arm movements: runs for 8 mins on 1ml of fuel
Potential for development of soft mini-robots without mechanical or electronic joints

Question 18

How can the artificial octopus arm be described?

Answer 18

Octopus arms soft and deformable, bending is omni-directional at any point along the arm
Arms can stiffen when needed, can grasp and pull objects with considerable strength
Potential application: Medical, underwater rescue, salvage of delicate submerged artifacts

Question 19

How else can artificial octopus arms be used?

Answer 19

Surgical manipulators
Organ retraction: manipulator grabbing and lifting an organ
In tiny spaces: Shifting an organ down and reaching the surgical target

Question 20

What’s the problems with wind power?

Answer 20

Low reliability, noise (especially at blade tips when stalling), poor performance during turbulence

Question 21

What’s the solution to the problems occuring with wind power?

Answer 21

Increase operating angle of turbine blades, however aerodynamic limits affect possible angles with conventional designs, which can increase stalling and drag, thus reducing efficiency
Biomimetic solution proposed based on observations of whale flukes/flippers

Question 22

What is the whalepower corporation?

Answer 22

Humpback-whale movement exceptional compared with other species, as angle of flippers up to 40% steeper than for other species, without stalling
Humpbacks capable of extremely tight circling in water, as well as maintaining speed without stalling
Conventional science dictates that turbines, wings or fins with smooth, stream-lined edges are least likely to stall

Question 23

What’s the difference between humpback flipper and other ones?

Answer 23

Humpback flipper not smooth, front edge carries bumps, known as tubercles
Tubercles change pressure distribution on the flipper, resulting in only some parts experiencing, thus abrupt stalling avoided
Instead of blocking flow, tubercles channel flow between bumps

Question 24

Can robotics help in pest control?

Answer 24

Yes- the COTSbot
Vision-based underwater robotic system for the identification/control if crown-of-thorns starfish (COTS)
Pests that periodically kill large swathes of coral
Control traditionally done by divers injecting individual starfish with ox-bile or vinegar by hand
A robotic injector was developed to improve eradication efficiency, diver safety and to reach inaccessible COTS
The robot is trained to recognize COTS on reefs based on colour and shape

Question 25

How does the COTSbot work?

Answer 25

Follows pre-programmed path, moving via 5 thrusters Navigates reef with multiple cameras Trained by starfish printed by 3D printers software programmed to recognize COTS wrapped around/under rocks On robotic identification of COTS, 10ml injected via pneumatic arm Injected starfish die

Question 26

How can biomimicry be used in fabrics/materials?

Answer 26

Armour, textiles: seahorses, sharks and squid Biomimicry to develop properties of strength, flexibility, camouflage, refractive or voltaic properties

Question 27

What are the important protein polymers in biomimicry?

Answer 27

Collagen Elastin Silks

Question 28

What are the SRT proteins?

Answer 28

Squid ring teeth (SRT) proteins: Films, shapes, and gels Predatory appendages inside suction cups Composed of protein complex Physico-chemical properties controlled by: i. amino-acid composition ii. 2 degree structure iii. overall network morphology iv. quantity of histidine Adhesion properties change as function of temperature

Question 29

How are SRT's controlled?

Answer 29

Native protein non-adhesive in either wet or dry conditions Non-adhesive below glass transition temperature Becomes adhesive when processed above glass transition temperature Important polymer property Temperature region where polymer transitions from hard, glassy material to soft, rubbery form Joints bonded with SRT protein

Question 30

How can SRT proteins be processed?

Answer 30

By using methods common in the polymer industry Solution based processing: H bond disruption Thermoplastic processing: heating above glass transition temperature

Question 31

What are the multi functional structures of SRTs?

Answer 31

Clear, free standing, flexible film Complex 3D shapes Incorporation of light sensors for photonics Insect wing biomimicry

Question 32

What is an example of a SRT protein?

Answer 32

Abrasion-resistant SRT protein coatings for textiles

Question 33

What does fish skin confer?

Answer 33

Fish skin un-keratinised and living, but covered with overlapping mineralized scales Confer mechanical protection, flexibility, hydration, regeneration, repair and camouflage Scale shape and arrangement varies across body

Question 34

How can fish skin be recreated artificially?

Answer 34

Designs can be re-created artificially with polymers, silicone or other materials

Question 35

How do fish scales respond to deformation by indentation, shearing and other forces?

Answer 35

By using macroscale synthetic prototypes, scales are tested by how their affected High scale overlap resists penentration by load distribution over larger area Authors considered that scale plates distribute the load of a predatory attack over a large area, thus mitigating stress Concluded that mechanical characterization of such layered, segmented structures fundamental for developing engineered protective systems/composites for other uses

Question 36

What can shark skin be used for?

Answer 36

Drag reduction and flow separation Drag on a submerged, swimming body: i. Form drag- difference in pressure around body ii. drag due to lift iii. skin friction due to boundary layer formation

Question 37

How does biofouling start?

Answer 37

Free fouling larvae transition to their attached forms, but early transition stage weak and reversible Irreversible attachment occurs by chemical binding via adhesive proteins, therefore one strategy is to block early attachment

Question 38

How can shark skin be anti-fouling?

Answer 38

As shark skin minimizes drag close to the body, this also reduces biofouling, as settlement time window reduced and faster-flowing water at skin surfaces deters settlement Furthermore, fouling organisms have preferred settlement structures in terms of optimal groove width/depth. Hypothesized that shark skin provides sub-optimal surface

Question 39

So what is shark skin used to develop?

Answer 39

Uses surface properties alone to develop anti-fouling and antibacterial films

Question 40

How do seahorses avoid being crushed?

Answer 40

Seahorses: segmented array of bony plates functioning as flexible, sub-dermal armour Seahorse predators: capture strategy is to crush Upon compression, overlapping bony plates slide past each other Compression of tail up to 50% it's original length without permanent damage

Question 41

How can seahorses be applied to biomimicry?

Answer 41

Potential application for steerable catheters, earthquake resistant structures, flexible body armour, controlled anchors, prehensile robotics

Question 42

How is the seahorse skeleton structured?

Answer 42

Micro-hardness tests: show distribution of hardness over single bony plate Harder on outer surface for protection but softer at overlapping joints for mobility Seahorse bony plates compress without damage

Question 43

How do sea horse bony plates compress without damage?

Answer 43

because of their structure as they are designed to slide past each other and buckle when compressed

Question 44

How can a glass oyster be used in biomimicry?

Answer 44

Windowpane oyster, unusually translucent (80% total transmission of visible light) Translucency may act as camouflage against predation Shell traditionally used as 'glass' Shell > 3000x tougher than the mineral Formation creates fissures which bend/deform, thus not transmitting cracks Nano-structure composed of tiled elongated diamond shaped calcitic laths (300nm thick)

Question 45

How can Bioceramic oyster shells be used?

Answer 45

Indentation of the shell surface causes particles on the leading edge of the dent to break into two identical blocks Break occurs all round the dent, forming boundary preventing damage from spreading Offers potential for building transparent energy-dissipating (impact resistant) armoured plates for military or other applications Currently engineered ceramics are prone to cracking and fracture, which could be mitigated by copying shell design