21 November 2013
The fate of bees, generally, is a matter of great concern these days. Bee populations throughout the world, and particularly in the United States and Europe, are dropping rapidly and mysteriously. Why are bees so important? Agricultural production. Without the bees’ unique service as pollinators, the value of yearly agriculture output would drop by billions and billions of dollars. But dollars aren’t the worst part of the problem. Agricultural production is food. Without bees, we’d have much less food than the minimum required feed the Earth’s population. So, without bees, a good portion of the people on earth will begin to starve – quickly. What would we do in a world without bees? You’re probably hearing more and more discussion on the topic, but not in this article.
Let’s ignore that pesky food production/global starvation issue for a moment and consider another bee-related question:
What would DARPA do in a world without bees?
What does DARPA need with bees? Well, these amazing insects are a seemingly endless wellspring of unique abilities. When the DEA isn’t planning to use bees for security-related activities, DARPA is studying this insect’s unique flight capabilities. But, I hear the reader asking, “security-related activities?” Yes, bees are being groomed to replace those large cumbersome flea traps on four legs — drug-sniffing dogs. A small hive of honey bees is so much easier to carry and care for than those hounds with their endless vaccinations, flea powder, and licensing requirements.
The bees don’t even have to leave home, but live in a mobile home or, rather, a box. When air is blown through their “buzz box,” their responsive behavior alerts officers to the presence of drugs. UK researchers beat everyone to this adaptation, but someday soon, there may be a canine unemployment issue as man’s best friend starts pounding the pavement looking for work after losing out to the new, cheaper, and less care-intensive honeybee.
As bees are drawn out of our agricultural fields to secure our borders (and other places) against drugs, it’s interesting to note that, even as bee populations decline, demand for the amazingly diverse talents of these critters keeps increasing. But let’s leave the story of the bees’ role in the war on drugs for another time and get back to DARPA.
DARPA’s first interest is drones. Not the bee kind of drones – male bees — but mechanical drones. More precisely, flying drones. What’s so special about bees when it comes to flying drones? Well, DARPA is trying to build a drone that is about size of a bee. Just as important, this bee-sized mini-drone must maneuver like a bee. What’s so special about the flight of bees?
There are two special things. The first thing is not only characteristic of the flight of bees, but of the flight of all insects. After bird-sized flying drones were developed, the next step was an insect-sized drone. Simple enough. You just shrink the bird drone down to insect size and – voila – you have an insect sized drone. But you don’t — because the shrunken drone won’t fly. UCLA Roboticist, Ronald Fearing, explains, “the rules of aerodynamics change at very tiny scales and require wings that flap in precise ways — a huge engineering challenge.”
Apparently, the relatively large bird can afford to be a bit sloppy with its wing movements, but insects must be much more precise. Of course, it would help to know exactly how insects fly. Contrary to the popular perception that science “knows everything,” only recently have researchers begun to understand insect flight.
Just a few decades ago, you’d sometimes hear the inaccurate assertion that scientists “said” that insect flight was impossible. Although probably no scientist ever said that, there was a grain of truth in the statement. In fact, until recently, scientists didn’t know how insects flew. That is, there was no theoretical description that could account for how these tiny creatures remained airborne. The relatively recent development of high speed microphotography together with the more recent intense technological interest in the flight of insects has led to substantial advances in the understanding of insect aerodynamics.
Dragonflies have been studied to determine how their front and rear wings coordinate to perform certain maneuvers, most notably, how they hover. And butterflies are the subject of intense study with the surprising discovery that even though many insects fly, different varieties use their wings in very different ways to accomplish maneuvers that have yet to be robotically duplicated on any scale – large or small.
Why all of this interest in insects all of a sudden? Because DARPA wants drones with certain, new capacities that were missing in past drone technology. To meet DARPA’s requirements, drones must be built to perform more like . . . wildlife.
In the 1950’s, the sci-fi vision of robotic technology was both exotic and strange. The technology of the future was envisioned and presented as something completely different and contrary to our natural biological surroundings. However, when technology confronted reality, we biological organisms seem to have had the last laugh because we could (and still can) do a whole lot of extremely useful things that our most sophisticated technology cannot.
The jeep took a basic automobile and raised the center of gravity, increased the size and scale of the automotive suspension system and produced spectacular off-road performance for a machine with wheels. But the wheel, itself, was limited. Every Rover we’ve sent to Mars ended its life when it got stuck. Human beings aren’t the strongest animal in the forest, but if just two of us were with those Rovers on Mars, we’d have extended their useful lives by getting them “un-stuck” in short order. Why? Because we have a repertoire of movements and leverage that we can use to apply force in almost any direction. The best of those early sci-fi ’bots looked high-tech but, in fact, were functionally stunted.
When sci-fi was still dominated by those inhuman and unnatural versions of mechanistic technology, a new technological methodology was, quietly, born. “Biomimetics” was a term used to describe the development of technology designed to imitate and replicate the activities of biological systems and organisms. Then, the term “bionic” was coined to describe a technology incorporating a “function copied from nature.” When Hollywood got a hold of the term “bionic,” the “Six Million Dollar Man” hit the small screen. But Hollywood’s version of the term “bionic” was just too interesting to be seriously “scientific,” and the term “bionic” fell into scientific oblivion.
The gap was finally filled with the introduction of the term “biomimicry,” which has been widely adopted to describe any technology imitating (copied) from nature. But, in some contexts, biomimicry is more of a necessity than a choice. If you want drones that work in a particular way, and the only known example of such performance is a biological organism, you’ll either have to imitate it or forget the project altogether.
And this brings us back to the bees.
The second special thing about bees is their flying ability. Among their fellow insects, bees are the virtuosos of flight. These insects can fly faster than most other insects. They can also fly slower, hover, in a way that most other insects cannot. And bees are remarkably precise in their flight. They maneuver with a precision almost unparalleled in the insect world. If you were DARPA and wanted to develop an insect-sized drone, you’d want its capabilities to be as close to those of a bee as possible.
Harvard’s “Micro Air Vehicles Project” is developing a robot that is intended to duplicate the functions of a honeybee. One day, it is hoped, these robo-bees will be engineered to fly in swarms, live in artificial hives, and locate sources of honey. But that goal is a long, long way off. If you believe some of the stories you read on the internet, the robo-bee is waiting like a vulture to take over when our natural biological honeybees die out. But, alas, it isn’t so.
Robo-Bee is a sensation because it can fly. But the word “fly” is used in the most restricted and technical sense. For most of the last few years, Robo-Bee has been able to flap its wings, and rise into the air – “fly.” However, when it does, it shoots from its starting position across the room and crashes into the nearest wall. Flight over. Total flight time – about a second.
Recently, however, researchers have figured out how to guide the robo-bee in flight. Now, with the latest guidance breakthrough, the robo-bee can be made “to pitch and roll in a predetermined direction” and, then, it crashes into the nearest wall.
While Harvard is working on Robo-Bee’s flight, you’ve got to wonder whose working on the crashes? Put another way, Robo-Bee crashes because it can’t land. And landing is the most challenging maneuver of successful flight. What insect, do you suppose, displays the most precise and graceful skill in landing? You guessed it. Landing is, perhaps, the bee’s most amazing talent.
Not only are bees remarkable for their landings, but where they land sets them apart from other airborne insects as well. They can land anywhere – not just on flat, surfaces, but on irregular, ridged, and vertical surfaces. But knowing that the bees “can do it” is one thing. Understanding “how they do it” is another.
What bees can do that so many other insects can’t is land almost anywhere smoothly. In order to land smoothly, a flying object must slow down almost to a stop at the landing location. So, landing isn’t just about the bee putting its, er, ah, . . . feet (or whatever) onto the ground. Landing is about speed and distance. To do it right, you have to estimate your distance from the place you intend to land and vary your speed so that you have just about stopped by the time you reach your intended landing spot. At least, you have to do all this if you want the bee’s characteristically smooth landing. A crash is a landing too. Just not a smooth one.
In the old days, human pilots made these estimations using nothing more than their vision. As human beings, we have two eyes set slightly apart. Each eye relays a slightly different image to the brain. Our brain compensates so that we are aware of only one image. But, without even realizing it, the slight differences in the images are translated by the brain into an awareness of the relative distances of the objects around us. Everything from navigating around objects in our home or apartment to driving on the roads would present difficulties, and even dangers, without our “stereo” vision. And, with nothing more than this vision, aviators used to gauge their speed relative to the distance of the chosen landing strip to bring aircraft to as slow a speed as possible at the point at which the landing gear made first contact with the ground.
However, pilots don’t use plain old vision these days. Sophisticated computers estimate distances for professional pilots. This can be done with or without the aid of global positioning signals. Computers can use no more than bits of data, distance from the destination, direction, and speed, to decelerate an aircraft to the slowest possible speed at the moment the landing gear touch the ground.
Bees, however, don’t have the equivalent of human “stereoscopic” vision. And they don’t have the benefit of computers. So, how do the bees land so well? The fact that bees seem to be able to land almost anywhere has provoked extensive study. A new discovery about just how bees accomplish their remarkable landings has been reported in the Proceedings of the National Academy of Sciences.
Professor Mandyam Srinivasan at the University of Queensland explains that bees “watch” an object, their destination, as they fly toward it. The rate at which their intended landing place “zooms in” tells the bee when to slow down and stop. However unfamiliar this method must seem to human beings, it allows bees to make almost perfect landings most of the time without any other information about distance or speed.
Professor Srinivasan uses an analogy from simulated interstellar space travel. As you approach a particular star, two things happen. First, the other stars, around your destination, seem to move away, while your destination star appears to become larger. In bees, nature has parlayed these simple observations into an amazingly sophisticated navigation and flight methodology. And researchers have been able to reduce the bees’ landing strategy to a mathematical model for guiding landings.
Professor Srinivasan added that this newest research can produce a substantial savings in the design and production of drone technology. An insect-sized mini-drone would not need radar, sonar or laser beams to determine surface speed and distances for landing. Dropping this expensive equipment would not only make the mini-drone cheaper, but the lighter weight would extend the drone’s range. Also, the same radar, sonar or laser beams creates detectible electronic signatures, which can compromise the drone’s stealth. In contrast, the “vision-based system” needs nothing more sophisticated than a video camera of the type “found in smart phones.”
So, someday, with further development, our bee-sized drones will be able to fly, maneuver, and land smoothly. But there’s still another question. Why do we need bee-sized drones at all?
Well, if you’re DARPA, you want these drones for reconnaissance and surveillance. Our bee-like drones would be useful in both departments. Because of their size, they are stealthy – small is more difficult to see. Also, because they are small, they can squeeze into and under objects and examine places too small for human beings and, therefore, not accessible to traditional aerial or satellite reconnaissance cameras. These small drones could examine areas and locate obstructions, unusual terrain, explosives and other potential dangers.
The other side of the reconnaissance and surveillance coin is search and rescue. Drones of this size are invaluable aids and can be used to examine the interior of collapsed building squeezing into the tightest spaces. They can locate injured victims as well as potential dangers to be avoided by search and rescue personnel.
One of DARPA’s high priorities is the development of mini flying drones. But what would a DARPA representative have said if, starting from scratch, they were asked how they wanted their new mini-drone to work? I can imagine a long silence. Then, catching sight of a nearby honeybee, they would point directly at the bee and say, “exactly like that.” If there had never been any bees, who would, or could, even imagine the performance capabilities of these amazing insects?
We aren’t “thinking-up” new technologies. Actually, we’re figuring out ways to technologically imitate an extremely old “technology,” organic life. Bees aren’t just useful workers in our agricultural fields (and soon, perhaps, our boarders and airports), but an inspiration for what would, otherwise, remain unimagined technologies. Today, we often hear the question: What would we do in world without the work of the honeybee? But no one asks, a perhaps less important, but more surprising question: What would DARPA do without the inspiring model of that same bee?