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So a robot has been created that allows it to recognize its own image in the mirror. Some may see this as a breakthrough in the development of artificial intelligence, but as Seth Meyers from SNL puts it, the robot will only be truly human when it learns to hate what it sees.


Kinetic Scultures

Theo Jansen visited my home country recently exhibiting his kinetic sculptures. His sculptures are able to move and evolve from interaction with the elements (ie wind and air pressure). His motto (from a recent BMW commercial) is that “The walls between art and engineering exist only in our minds,” as his work is often described as a fusion of art and engineering. However, I think for many engineers that wall is more concrete than imaginary.



Biomimetics in Industrial Design

Gecko Tape

Since our professor Dr. Hsieh studies extensively on the biomechanics of lizards and geckos, this alone makes the gecko tape worthy of mention. The gecko tape is a bio-inspired product that mimics the setae on the feet of the gecko. These microscopic hairs on the tape surface provide extensive surface area for van der Waals interaction with the contact surface. While mass manufacturing of the gecko tape is currently limited by production costs, one day the tape may help us anchor to objects in outer space or cling to walls and ceilings on Earth, much like the geckos that the tape mimics.

Butterfly-inspired Cosmetics and Fabric

The way that the human eye distinguishes colors is by sensing the wavelengths of light that hits the retina. Thus, manipulation of color and wavelengths can yield interesting results when these visual information are interpreted by the brain. The Morpho butterfly’s wings contain layered nanoscale ridges and structures that reflect blue wavelengths. In addition, the angular visibility is enhanced by the reflection of incident at different layers. This produces a metallic, shimmering color that varies with viewing angle. The same concept has been applied to cosmetics and fabric to produce unconventionally brilliant colors.

Self-healing Materials

Scar tissue is a fibrous connective tissue that helps protect a healing wound. This promotes faster wound healing while preventing any additional injuries. This is the idea behind the development of self-healing materials. Self-healing materials contain hollow fibers that are filled with an epoxy resin. When the material fails, the resin flows out, hardens, and quickly seals the break to prevent any further damage. This facilitates actual repair by stabilizing the original structure while making damages easy to identify.

Setae on Gecko Tape

Morpho Butterfly

Self-healing Material

Human power

A French lab at the Joseph Fourier University has been working on developing biofuel cells. They have recently created an implantable device that can generate electricity from glucose and oxygen. Electricity is generated using carbon nanotubes and the enzyme glucose oxidase, which extracts electrons from glucose molecules. This technology has the potential to resolve power issues with artificial organs and limbs. In the short term, the biofuel cell can be used to power small biomedical devices such as insulin pumps in diabetic patients. The device has been demonstrated to work in rats with no noticeable complications. The next step will be scaling for greater power generation and clinical testing in humans.

The Biofuel Cell

Much ado about poop

During our class brainstorming for the final project, three major topics emerged: 1) food production, 2) waste management, and 3) energy production. No one seemed content to head towards just one of these three directions because of the vast potential that lies behind each of these topics. Besides, why limit yourself to one? If you are given the chance to resolve the world’s problems it’s just that much more convenient to come up with an answer that can cure everything.

Of course, a dash of practical thinking is probably necessary to progress past the brainstorming stage, but the potential connections between the three topics should not be overlooked. For example, linking waste management solutions to energy production makes sense to me. In the medieval ages, alchemists have been obsessed with turning junk into gold (okay..maybe not really ‘junk’ but other elements of less value). Although we all know better now, it still has not stopped the modern alchemists from keeping the same concepts alive. In Cambridge, MA, the Park Spark Project (link) created containers that use bacteria to extract methane from dog poop, which is then used to power street lamps. This idea has now spread to parks in Denver, CO. In Japan, toilet maker TOTO fitted one of their toilets onto a motorcycle that runs entirely on human/animal waste (link). The idea is simple: find/make poop –> motorcycle converts poop to biogas –> biogas powers motorcycle –> rinse and repeat. TOTO’s “Toilet Bike Neo” is currently on a month-long journey across Japan to promote green practices. These initiatives to turn waste into energy is just a glimpse of what the future holds for alternative energy solutions.

If you think about it, being able to turn something useless into something of value like energy is a simple concept that’s easier said than done. However, the Park Spark Project and TOTO’s toilet motorcycle are steps in the right direction, and I am eager to see more ideas jump-started by these initiatives. There’s a saying that one man’s trash is another man’s treasure. As we develop to become more and more self-sustainable, perhaps one day one man’s trash can become everyone’s treasure.

TOTO's Toilet Bike Neo


Function Organism Strategy
Packaging Ant Form: The honeypot ant functions as a means for food storage in the honey ant colony. The abdomen of these ants swells (plerergate) when filled with food harvested by workers. Honeypot ants are usually found underground where other ants can extract food from their abdomen. In addition to food, honeypot ants can also store liquids, water, and fat. (
Monarch Butterfly Form: During the pupal stage of the monarch butterfly, the caterpillar will shed for the last time to form the chrysalis. The chrysalis is a hard skin that protects the caterpillar as it transforms into a butterfly. The chrysalis is attached to a surface using velcro-like structures made from silk.
Water purification Yellow iris Process: The yellow iris can purify water by extracting chemicals and carbon dioxide from the water. In particular, the yellow iris can purify eutrophic water by extracting nitrogen, nitrates, and phosphorous elements as nutrition. (
Common reed Process: The common reed, like the yellow iris, is able to purify water sources through phytoremediation. The common reed is a halophyte that can tolerate alkaline habitats. The plant is able to absorb and accumulate heavy metals from the water such as mercury, copper, zinc, chromium, and lead. (Ye ZH, et al. (1997). Zinc, lead, and cadmium tolerance, uptake and accumulation by the common reed. Annals of Botany. 80 (3): 363-370.)
Water availability Sphagnum Moss Process: The empty cells of the sphagnum moss help it retain water in dry conditions similar to a sponge. In wetter conditions, the water in the cells can be replaced with air. This allows the moss to float above moisture to promote photosynthesis.
Squirrel Process: The squirrel goes into a hibernation state in the winter to survive conditions where food and water are scarce. During hibernation, the metabolism of the squirrel slows down dramatically, decreasing the need for food for water. In addition, slowed heart and breathing rates result in decreased water loss from respiration.
Transportation of materials Ant System: Ant workers utilize a complex array of information to optimize the shortest route to a food resource. In addition to navigation using the earth’s magnetic field or the position of the sun, it has been hypothesized that ant traffic flow is comparable to fluid flow. Unlike human pedestrian traffic, ants welcome collisions with oncoming workers as a means for information exchange. Since ants are capable of rapid acceleration and deceleration, collisions do not slow down traffic. It has been hypothesized that ant traffic can be described with a fluid dynamic model where ants collide similarly to elastic gas particles. (Burd M, et al. (2002). Traffic dynamics of the leaf-cutting ant, Atta cephalotes. The American Naturalist. 159: 283-293.)
Dung Beetle Process: The dung beetle feed on the excretion of other organisms as the source of nutrients. When a beetle finds a food source, it will roll the dung in a straight line regardless of any obstacles. Dung beetles may be able to use polarization patterns of moonlight for navigation during dung transport. (Dacke M, et al. (July 2003). Animal behaviour: insect orientation to polarized moonlight. Nature. 424: 33.)
Protection from biota Mantis Form: Mantises rely heavily on camouflage as defense mechanism against natural enemies. Many species have appearances that mimics leaves and twigs. Certain species even have bright colors that resembles flower petals or morphologies that mimic small ants. (
Monarch Butterfly System: The monarch butterfly utilizes a variety of mechanisms for defense against predators. Monarchs accumulate large quantities of cardenolide aglycones in their body that come from the milkweeds that were consumed during the larva state. The cardenolide is a type of steroid that are both foul-tasting and toxic to predators. In addition, the monarch butterfly uses its bright colors as a form of  aposematism to warn potential predators. The aposematism and presence of cardenolides work together to defend against enemies. (Brower LP, Fink LS (June 1985). A Natural Toxic Defense System: Cardenolides in Butterflies versus Birds. Annals of the New York Acad. of Sci. 443: 171-188.)
Cleaning Pigeons Process: Pigeons, like other birds, engage in constant preening of their feathers to remove foreign objects. In addition, they utilize an oil from the preen gland to make their feathers more hydrophobic. This allows less water retention in the feathers resulting in better aerodynamics. (Bormashenko E, et al. (July 2007). Why do pigeon feathers repel water? Hydrophobicity of pennae, Cassie-Baxter wetting hypothesis and Cassie-Wenzel capillarity-induced wetting transition. Journal of Colloid and Interface Sci. 331 (1): 212-216.)
Stick Insects System: The feet of stick insects contain smooth pads that allow adhesion to different surfaces. However, the adhesive forces also attract dust and dirt. To counter this, the stick insect utilizes a sliding movement that induces shear on the articulating surface.  The sliding movement helps detach particles to promote better adhesion on the next step. (Clemente CJ, et al. (Feb 2010). Evidence for self-cleaning in fluid based smooth and hairy adhesive systems of insects. Journal of Exp. Bio. 213: 635-642.)
Absorbing Smallmouth Bass System: The smallmouth bass is a common freshwater fish. Like other bony fish, the smallmouth bass utilizes its gills for gas exchange in the water. The process is facilitated by the thin tissue membrane in the gills, which are folded to increase surface area. During gas exchange, oxygen from the water diffuses down the concentration gradient into the blood while carbon dioxide diffuses from the blood into the water. This exchange is also facilitated by the countercurrent system where blood circulation flows opposite to the flow of water. This facilitates gas exchange by increasing the concentration gradient.
Sphagnum Moss Form: The structure of the cells of the peat moss is capable of absorbing up to 20 times its dry weight in water. This is because the morphology of the moss is similar to a big sponge with hollow hyaline cells. The moss can retain water in these cells by releasing hydrogen. ($54)
Communication flows Ant Process: Ants are social insects that utilize pheromones for communication. Most ants leave pheromone trails on the soil surface that are picked up by other ants via their antennae. Pheromone trails are left for other ants to indicate successful routes to a food source or alarm nearby ants of enemy presence. Pheromone trails that are picked up by other ants are amplified by the release of more pheromones. On the other hand, alarm pheromones instigate nearby ants into a state of frenzy and recruits more ants from farther away. (Jackson DE, Ratnieks FL (August 2006). Communication in ants. Curr. Biol. 16 (15): R570–R574.)
Bee Process: One popular theory that describes how bees communicate with each using dance language. Bees use dancing as a method to recruit and direct other bees towards a food source. The theory proclaims that the bee initiates a round dance to alert other bees of a food source near the hive. On the other hand, a waggle dance embeds information on the location of the food source. The tempo of the dance informs other bees of how far the source is (faster = closer) while the angle of the dance with the sun tells directional information. (
Feedback systems Empress Tree System: Phytochrome is a photoreceptor in plants that detects light. Like many other plants, the empress tree relies on the phytochrome pigment to regulate germination. In fact, the winged seeds from the empress tree are shade intolerant and require detection of light in order to germinate. The empress tree cannot survive when succeeded by the shades of other trees. In addition, seed germination is also influenced by temperature, which in turn affects the light sensitivity of the seeds. The tree uses various environmental data to determine the optimal conditions for seed germination. (Grubisic D, Konjevic R (1992). Light and temperature action in germination of the empress tree. Physiologia Plantarum 86: 479-483.)
Ant Process: The communication process of ants relies heavily on pheromone trails. When a forager finds a new food source, it will leave a pheromone trail as it returns to the colony. Other ants that that follow the trail can confirm the food source by reinforcing the trail or vice versa if the source is depleted. This process effectively marks the most successful routes for the rest of the colony while trails to a depleted source slowly disappear over time. (Goss S, Aron S, Deneubourg JL, Pasteels JM (1989). Self-organized shortcuts in the Argentine ant. Naturwissenschaften 76: 579–581.)
Protection from abiotic factors Squirrel System: Squirrels are able to survive the harsh conditions of winter by going into hibernation, a state characterized by significant reductions in metabolism, body temperature, and heart rate.  A byproduct of this is decreased oxygen and glucose flow to the brain. Upon hibernation, complex cellular interactions, possibly involving the small ubiquitin-related modifier protein, that promote cytoprotection and suppress apoptosis are activated. This helps preserve important organs (i.e. brain) that would have otherwise been critically damaged under similar oxygen and glucose-deprived conditions. (Lee YJ, Hallenbeck JM (2006) Insights into cytoprotection from ground squirrel hibernation, a natural model of tolerance to profound brain oligaemia. Biochem Soc Trans. 34(Pt 6): 1295–1298.)
Termites Process: Termites can construct shelter tubes out of feces, plant tissues, saliva, and soil for protection of trails and routes. These shelter tubes are capable of protecting termites from unfavorable weather conditions.

In the harsh grasp of Winter’s bitter cold, the Fairmount Park’s serenity gives order to the chaotic winds and bustling action in nearby Center City. When the Spring sun rises in the city, Fairmount Park welcomes Winter’s end by littering the banks of the Skuykill pink with cherry blossoms. With a collective area of over 9,000 acres, Fairmount Park is essentially the lung of Philadelphia. Fairmount Park is symbolic for the City of Brotherly love, providing animals with a natural habitat in which to coexist with human residents of the city who seek an accessible elixir for the stressful life of Philly.

Fab Ride

My Canon MX870 sits faithfully on my desk, patiently awaiting to receive its next task. It’s a solid printer: it’s fast, it scans and prints wirelessly, and it even does double-sided printing automatically. In fact, it’s really an awesome printer…that is, until I read about the Urbee. The Urbee is a hybrid vehicle dubbed “the world’s first 3-D printed car.” In the book Biomimicry: Innovation Inspired by Nature, Janine Benyus dedicated a few paragraphs discussing the potentials of manufacturing using 3-D printing. The idea is that a three dimensional object can be fabricated through layering of accessible materials using a printer-like machine (a “fabber”). One thing that technology news does to you is make you realize how hopelessly outdated and useless everything you own is. What’s that? The Urbee also does 200 mpg on the highway and 100 mpg in the city? Now I hate my car.

Moore’s Law

Generic Picture of Object in Nano-scale

In the realm of electrical engineering, almost everyone is at least somewhat familiar with what is known as Moore’s Law. What Gordon Moore, the man in which the law was named after, observed was that the number of transistors that can be economically placed in a circuit roughly doubles every two years. This trend that Moore described and published in the 60’s is still observed in the semiconductor industry today.

In the field of biology, a big part of what makes biological processes and mechanisms so effective is often the incredibly high surface areas capable of interaction. Similarly, the degree in which we can mimic the effectiveness of these biological processes depends on how well we can engineer and manufacture materials in the nano-scale. Perhaps a trend similar to Moore’s Law in nanotechnology can also be applied to predict the development rate of bio-inspired products in the future.

Observations and random abstractions


Close-up of Mosquito Feet

I hate mosquitoes. They like my blood and they are downright annoying. I am glad to  have the opportunity to study in the States where they are less of a problem (so far). The unfortunate truth is that they might eventually outlive us despite our best efforts to eradicate these pests. Whether we like it or not, these little insects are highly versatile creatures. Close up images of mosquito feet reveal velcro-like hooks that clutches onto skin and hairs that adheres to smooth surfaces. In addition, the surface of these feet are highly hydrophobic, thus allowing each to be capable of supporting up to 23 times the mosquito’s weight on water. Sun Tzu’s The Art of War highlights the importance of knowing your enemy, and I believe that the we can learn from the hydrophobic microstructures of these mosquito feet. Perhaps one day when we have melted all the ice from the Earth’s poles and water covers the planet we can still confidently say, “An ark? We don’t need to build no stinkin’ ark!”


Eastern Skunk Cabbage in Snow

Speaking of global warming, the harsh winter season that is quickly approaching  will again convince me that global warming may just be a myth. Around the globe, a variety of thermogenic plants such as the eastern skunk cabbage have the ability to raise their temperatures up to 15-35 degrees C in cold weather. Thermogenic plants may be adopted to provide alternative heating in homes during the winter. In addition, better understanding of the thermogenic mechanism may allow the engineering of transgenic species that can lead to increased crop yields in cold climates. However, there are obvious complications when studying a plant named the eastern skunk cabbage.

My sister recently moved to New York City to attend college. My family bought her a pepper spray as a precaution to prepare her for life in the concrete jungle. The pepper spray is the man-made counterpart of the bombardier beetle. When threatened, the bombardier beetle expels a hot, pungent liquid composed of hydroquinone and hydrogen peroxide to ward off its enemies. The beetle protects itself from the scorching chemicals with an array of special valves. While the bombardier beetle uses its defense mechanism  frequently for survival, I hope my sister will never have to use her pepper spray.

If you are a male student in the engineering department like me there is one thing that you will come to accept when you decide to take on the social responsibility of becoming an engineer. A recent study shows that the percentage of female graduate students in engineering in the US hovers around 20%. This brings us to our next point. A typical honey bee colony consists of one queen bee and thousands of male drones (as well as numerous female but non-reproductive workers). In certain species, a gelatinous compound seals the reproductive tract of the queen bee after mating, effectively functioning as a biological counterpart to the chastity belt. Fun fact: one can observe similar levels of productivity in a bee colony and an engineering lab!