‘BOTS: The Insectothopter – The First Miniature Unmanned Aerial Vehicle

4 September 2014

The Insectothopter

THE RUMOR

            There is rumor about a flying robot.  At recent political events in Washington D.C. and New York, several people said they saw something that they described as a cross between a slightly over-sized dragonfly and a miniature helicopter.  Maybe these reporters mistook real insects for robots . . . or maybe not.  [1]

            There are no insect-sized UAV’s.  The smallest is a bird-sized 'bot -- the Nano Hummingbird.  Formally named, the “Nano Air Vehicle” (“NAV”), this bird 'bot was developed, in 2011, by AeroVironment, Inc. under the direction of DARPA

"Nano Air Vehicle" or Robo-Hummingerbird

THE PROBLEM IS FLIGHT

            So, if you want an insect-sized robot, why not just shrink Robo-Hummer down to the size of an insect? 

            The problem is flight.

            With robotic insects, flight itself is the biggest challenge.  While bird-sized flying drones are now being developed with relative success, flying insect ‘bots present a special aerodynamic problem.  It’s the size.  If you shrink a bird-sized drone down to the size of an insect -- it won’t fly. 

            A roboticist at the University of California at Berkeley, Ronald Fearing, told the Washington Post that “the rules of aerodynamics change” with an object as small as an insect.  [2] Unlike bird wings, insect-sized wings must move with amazing precision. 

            Replicating these precise wing movements is a major engineering challenge.  In fact, scientists only recently came to understand how insects fly at all.  Compounding the problem, these precision wing movements require yet larger supplies of portable power.  [3]

SOME HISTORY

            While robotic insect flight, in reality, has yet to be mastered by modern technologists, in science fiction, the technology was mastered in 1936 in Raymond Z. Gallun’s The Scarab.  Gallun’s robotic beetle flew like any other insect, but transmitted to its “manipulator” what it heard and saw through its “ear microphones” and “minute vision tubes.”

            Philip K. Dick refers to a commercial robotic fly in his novel, The Simulacra.

            Fast forward to the 1970’s.  America’s CIA (Central Intelligence Agency) had developed an eavesdropping (listening) device, but needed a way to use it.  In other words, the agency needed a way to “deliver” it to a target location.  Needless to say, the delivery had be unnoticed if the device was to serve its purpose.

Insectothopter

THE FIRST MINI UAV

            An insect-sized mini UAV seemed ideal.  And, of course, making the UAV look like an actual insect solved another problem - camouflage.  It wasn't enough to get the listening device to the target.  The target must, also, not know that the device was there.  

            At first, the bumblebee was to be the model for the mini UAV, but this insect was rejected due to its erratic flight.  One project member, reasonably familiar with insects, suggested the dragonfly.  This proved to be the almost perfect solution.

            One has to admire the simple ingenuity that went into the construction of what would become the Insectothopter.  Even with all the grants and theoretical computer models of today, the development of an insect sized drone remains in the future.   Yet, in the 1970’s, a group of project technologists just did it – in rather short order. 

            Today, we are just learning exactly how insects manage to fly.  But the CIA technologists of the 1970’s didn’t bother with the science true insect flight.  Instead, they just designed a set of wings with up and down movements that gave the Insectothopter both lift and thrust.

            Today, the development of a light, yet powerful, propulsion system for small drones remains a daunting task.  But in those far off days of the 1970’s, the CIA technologists simply used a gasoline engine to power the Insectothopter.  Certainly, the engine was loud, but the project members had selected their "model" insect well.  Have you ever heard a dragonfly in flight?  The gasoline engine probably made less noise than the real flying dragonfly. 

            But how could you design a gasoline (or any other kind of) engine that small?  Today, it would require a staggering amount of dollar grants and a consortium of research facilities to design a computer simulated prototype.  But, in the 1970’s, you just found a good watchmaker.  And project did just that. 

            The result was a miniature oscillating engine that would make the wings beat.  A fuel bladder carried the engine's liquid propellant.  Not only did the liquid propellant power the engine, but the excess gas was vented out the rear of the mini UAV, giving the Insectothopter added thrust.  The Insectothopter was directed using a laser beam and, finally, was hand-painted to look like a dragonfly.

Insectothopter

            But the insectothopter never made it into the field.  It’s downfall was its inability to withstand cross-drafts.  Real insects can drift a bit with the wind, but the operator of a surveillance drone must be able to direct it to a target if any meaningful surveillance is to take place.  Only a five mile per hour crosswind would throw the insectothopter off course.

            Today, the smallest operational UAV is AeroVironment’s “Nano Air Vehicle” (“NAV”).  With the story of the Insectothopter in mind, it’s easier to understand why DARPA’s project specifications for that project required that the “Nano Air Vehicle” demonstrate the ability to hover in a 5 mph side-wind without drift of more than one meter.

"Nano Air Vehicle" or Robo-Hummingerbird

THE END?

            So, with the retirement of the Insectothopter, the development of robotic insects ended -- only reappearing with the modern resurgence of robotic research. 

            But remember those recent political events in Washington D.C. and New York, at which several persons said they saw something that they described as a cross between a slightly over-sized dragonfly and a miniature helicopter.  Maybe these reporters mistook real insects for robots . . . or maybe not.

            Is it possible that the CIA secretly continued to develop insect drones?

            Has some U.S. Government agency developed a secret, advanced version of the Insectothopter?  Sources at the CIA have declined to comment.  When questioned about the possibility of the secret development of flying drone insects, an “expert in unmanned aerial vehicles,” retired Colonel Tom Ehrhard, simply said, "America can be pretty sneaky.”  [4]

About the Author

 

'BOTS: Robo-Roach? Just What We Need?!

12 June 2014

            A robotic cockroach?

            Okay.

            What is this ‘bot going to do that is so bad that it earned the name “cockroach?”

            There are other robotic insects in the research and development phase.  Scientists at Harvard are continuing to work on the development of the first robotic bee.  The goal is a robot that can pollinate flowers and crops just like a honeybee.  However, the goal is still far away. [1]

            Harvard’s “Micro Air Vehicles Project” is using titanium and plastic to fashion a robot that duplicates the functions, if not the appearance, of the familiar honeybee.  The robo-bee pops up, complete with wings, from a quarter-sized metal disk.  One day, it is hoped, these “bees” will be engineered to fly in swarms, live in artificial hives, and locate sources of honey. [2]

            But a “Robo-Bee” just has to be a “nice” robot.  After all, who doesn’t like honeybees?  Even though bees are insects, they’re some of the hardest workers in a major human industry – agriculture.   Not only do bees work in agriculture, but agriculture would be pretty much impossible without them.  Bees pollinate crops.  And who can really dislike a bug that makes honey?

            But cockroaches are really unpopular.  Consider another robot named after a “less than popular” insect.

            There’s a robot in the works called “Robo-Fly.”  But this brings up a question.  Why would anyone want to develop a robotic fly?  Bees are more than useful, and who can forget the honey-making.  But the fly?  It’s one of the most hated insects of all time.  But the mystery of “why robo-fly?” is actually a question of semantics – it’s about “names.”

            In fact, Robo-Fly is exactly the same robotic insect that is being developed as Robo-Bee.  Why give the same small robot two different names?  And, why give it a nice name “bee” and, then, a not-so-nice name “fly?”

            Well, it’s about market positioning.  The names “bee” and “fly” are more about what these little robots are sold to do.  Does that mean the Robo-Fly will do what flies do -- land on food at outdoor gatherings and irritate dogs on hot summer days?  No, it’s even stranger than that.

            When perfected, the “Micro Air Vehicle” will be marketed as Robo-Bee when it is to be used to do what bees do – pollinate crops.  But this same insect-sized robot will also be marketed as a mini surveillance drone.  The surveillance drone gets the not-so-nice name: Robo-Fly.

            Look at it this way.  When the robot is intended to secretly watch and, perhaps, eavesdrop on some unsuspecting victims, it gets a less flattering name like “fly.”   Surveillance is useful but, today, has developed an ugly reputation.  Don’t get me wrong, when a flying drone spies on “the enemy,” it’s okay.  When it spies on my neighbor, it’s a subject for public debate.  But, when it spies on me . . . it’s downright evil!

            So the Micro Air Vehicle is a lovable Robo-Bee when it’s hard at work pollinating crops in our fields.  But it is an unwelcome “Robo-Fly” when it’s looking over our shoulders and eavesdropping on our private lives.

            So, that brings us back to Robo-Roach.  What is this ‘bot going to do that is so bad that it earned it the name “cockroach?”

            Well, it isn’t actually named “cockroach.”  It’s called “roach,” but that’s only part of its name.  Its full name is VelociRoACH.  The “veloci” means speed, and that’s what it’s got.  It’s fast.  So, the “cockroach” name mystery is solved when you realize that cockroaches are very fast critters.

            So, Robo-Roach isn’t about making an indestructible pest to replace the one humanity spends millions of dollars yearly to eliminate.  It’s about imitating what the cockroach can do: run fast. The concept is biomimetic or what is sometimes called biomimicry.

            “Biomimetics” is a term used to describe a methodology of approach to technological design: the development of technology designed to imitate and replicate the activities of biological systems and organisms.  Some time ago, 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. Maybe Hollywood’s version of “bionics” was just too interesting to be seriously “scientific.”  Whatever the reason, the term “bionic” fell into scientific oblivion.

            The gap was filled by the term “biomimicry,” which has been widely adopted to describe any technology imitating (copied from) nature.  Sometimes, biomimicry is more of a necessity than a choice. If you want robots that work like a biological organism, you’ll either have to imitate the organism or forget the project altogether.

            The cardboard Robo-Roach or, rather, VelociRoACH was conceived by Duncan Haldane and his colleagues at UC Berkeley’s Biomimtic Millisystems Lab.  This 4 inch-long robot “runs” at about 6 mph.  For its size, it’s the fastest robot in the world.

            Their real-life model?  The American cockroach.

            Why?  That same cockroach is one of the fastest insects in the world.

            But what about the evil, roach-like purpose for which this ‘bot is intended?  Actually, VelociRoACH has no evilpurpose at all.  It’s designed to be a search and rescue ‘bot.

            Okay, but what’s with the “cardboard?”

            Actually, the cardboard is one of this robot’s most important features.  Haldane explained, “The idea is that we can build a huge number of very cheap, bio-inspired robots with remarkable mobility to quickly find people trapped in a disaster site.”

            VelociRoACH is designed to go where human beings can’t in a disaster situation. The ‘bot is intended to assist in the location of the injured and provide information to assure the safety of rescue personnel.   VelociRoACH’s C-shaped legs work like springs, just like those of a cockroach.  With three of its six legs on the ground at all times, when it runs, the ‘bot remains remarkable stable.  But it’s most interesting feat is the way it handles obstacles.  It does just what a real roach does – it runs right into them -- head first.  This throws the VelociRoACH back into an upright position from which it crawls right over the obstruction.  This, by the way, is exactly how the real cockroach deals with obstacles. 

            Well, considering how useful our Robo-Roach will be, I guess we can tolerate at least one robot designed to imitate one of our less than favorite critters.  At least, they didn’t design a Robo-Lizard.

            Oh, wait.  They did. 

            Same team.  Different day.

            “Clash” is a 4 inch, six-legged robot with a tail.  It climbs near-vertical surfaces with the aid of a “gecko-inspired adhesive” on its feet.  Observers agree.  This ‘bot looks like a lizard.

The End?

M Grossmann of Hazelwood, Missouri & Belleville, Illinois

About the Author

Of interest:
 
Cardboard cockroach ranks among world's fastest robots

Robotic cockroach faster than the real thing

VelociRoACH: A tiny robotic cockroach with a need for speed

VelociRoACH: A Tiny, Super-Fast Robot Cockroach Made from Cardboard That Can Save Lives

‘BOTS: Maveric -- The Bird ‘Bot

10 June 2014

            What is DARPA looking for in the mini UAV, an “Unmanned Aerial Vehicle?”  Well, if you go to their website you’ll find (1) that DARPA knows what it wants, and (2) it produces some long lists of “required” or “necessary” project objectives.   

            But let’s take a step back and refocus on the big picture.  DARPA is looking for mini UAV’s with two characteristics.  First, maneuverability – a maneuverability that rivals the most remarkable flying critters -- birds and insects.  The ideal surveillance and reconnaissance mini-drone would be able to “investigate” its environment with the resourceful maneuverability of a flying insect or bird searching for its next meal.

            Second, DARPA wants camouflage.  It’s one thing to develop a mini UAV able to engage in surveillance and reconnaissance activities.  But, the information obtained through surveillance and reconnaissance is most valuable when the "subjects of observation" do not know they have been observed.  To accomplish this, a mini UAV must not be easy to see or, at least, easy to identify.

            So DARPA wants a UAV that (1) maneuvers like the most acrobatic of birds or flying insects and (2) will not be identified as a UAV by an observer.  Amazingly, these are not conflicting objectives.  In fact, animal-like maneuverability and camouflage dovetail perfectly.

            What DARPA calls “biologically inspired” is, in robotic technology, referred to as “biomimetics” or “biomimickry.”  These terms describe a kind of revolution in the concept and design of robots. 

            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 the first term used to describe the development of technology designed to imitate and replicate the activities of biological systems and organisms.  Then, another term, “biomimicry,” was widely adopted to describe any technology imitating (copied from) 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 the organism or forget the project altogether.  So, to get flying ‘bots that maneuver the way flying insects and birds do, the ‘bots must be designed to imitate the actual form and movement of these same creatures.

            But, once you manage to replicate the form and functionality of a flying insect or a bird in a UAV, how do you camouflage it?  That's easy.   Disguise it as . . . a flying insect or a bird!  In modern robotics, biomimckry and camouflage often go hand in hand.

            A little more detail.  This form of camouflage is of a type called “mimesis” or “masquerade.”  The masqueraded object is quite visible to the observer, but is designed to be mistaken for something else.  That “something else” would be of no particular interest to the observer.  So, when the mini UAV flies overhead, those who are being reconnoitered will think, “It’s just a bird.” 

            An early attempt at this combination was the “Insectothopter.”  Everyone “knew” that the techno-savvy needed to build a robotic insect that actually flew like the real thing was not available in the 1970’s.  But the CIA did it anyway.  The laser guided Insectothopter was powered by a small gasoline engine.  Loud?  Maybe, but if you’ve ever heard a real dragon fly as it flies past your ear . . . .  Well, you’d hardly notice the difference. 

            But the Insectothopter never was “deployed” because of a stability issue.  For a mini UAV to be effective in surveillance and reconnaissance, the operator had to be able to direct it to a defined target.  With the Insectothopter, a  five mph cross-wind made such navigation impossible.  

            Only in 2011 was the next bio-inspired mini UAV unveiled.  The “Nano Hummingbird” or, technically, the “Nano Air Vehicle” (“NAV”) was the first fully functional bird-drone designed and able to perform surveillance and reconnaissance missions.

            The “Nano Air Vehicle” project began in 2006 with Aero Vironment, Inc. working under the direction of DARPA.  If you know the history of the Insectothopter, you can appreciate the significance of one of the DARPA project requirements:  the Nano Hummer must demonstrate the ability to hover in a 5 mph side-wind without drift of more than one meter.

            Robo-Hummer was the first successful surveillance and reconnaissance bird ‘bot.  But Robo-Hummer was designed in imitation of the hummingbird -- nature’s version of helicopter.  DARPA also wanted a bird ‘bot that would perform more like a winged aircraft.   The next bird ‘bot would be capable of high-speed flight.  But it would, also, have an appearance close enough to that of a bird to achieve masquerade.  In other words, the viewer would mistake the mini UAV for a bird.

            Florida’s Prioria Robotic responded with a mini UAV -- Maveric.  In terms of its field capabilities, Maveric is an amazing technical achievement.  This UAV can be carried, launched and operated by a by a single person.  The entire bird ‘bot is “bendable” and when not in operation, is carried fully assembled, but folded up, in a 6 inch tube.  The operator simply (1) pulls it out of the tube, (2) powers it up, (3) checks its sensors, and (4) launches it by throwing it into the air.

            In flight, Maveric can reach a speed of 55 knots (63 mph). More amazing is Maveric’s fully autonomous operation from launch to landing.  How does it know its target?  It has a point-and-click feature that allows the operator to find the target on a screen.  Then, point and click on the target.  After launch, what does the operator do next?  Often, nothing.                                                                        

            Maveric is able to operate with full autonomy from launch to landing.  This ‘bot doesn’t require a human pilot to operate it in flight.  The operator need only define the mission – that is -- where to fly and where to land.  How does Maveric do it?  Through the use of a system called Merlin. 

            Merlin is Prioria’s proprietary processing platform.  The Merlin “brain” is carried and contained entirely on board Maveric during flight.  The “brain” processes images and operates vision-based controls – without the assistance or necessity of a human operator.  This makes Maveric the first smart SUAS, “Small Unmanned Aerial System.”   Of course, Maveric can also be flown manually with a joystick while still providing the “pilot” with autopilot assistance.

            Of course, from a distance, Maveric looks like a bird.  And, in many environments, can be expected to be mistaken for bird.  Its smart system also provides a measure of stealth in terms of electronic transmissions.

             Radio signals providing a live audio or video feed to the remote operator are as common in surveillance drones as they are problematic.  The “problem” is radio waves.  These radio transmissions create a detectable signature that can disclose the presence and location of a surveillance drone. 

            With Maveric, the operator can control the timing of transmissions to delay broadcast of the live feed in sensitive locations – locations in which a radio transmission might be detected and recognized.  These transmissions aren’t lost -- only delayed.   Transmission will resume based on the operator’s instructions.

            Of course, some might question the usefulness of this radio stealth.  After all, Maveric’s use of radar and other navigational signals could just as easily disclose its presence.  But Maveric makes only very limited use of any “other signals.”  

            How does it manage that? 

            Merlin has some more magic.  The Merlin “Brain” also engages in on-board image processing with on-board vision based controls.  In other words, Maveric avoids obstacles and finds its target by sight.   This 'bot carries a self-contained vision-based navigation system, which allows it to perform it mission without real time human assistance, while minimizing the use of any electronic navigation systems that produce detectable radio signatures.

            Of course, Maveric doesn’t look exactly like a bird.  It has the silhouette (shape and color) of a bird, but, unlike Robo-Hummer, Maveric doesn’t have the bodily movements of a bird in flight.

            Is that an issue?  Well, DARPA is working with the Army Research Laboratory and the Maryland Robotics Center to produce yet another bird 'bot with the flapping wings and the bodily movements of a real bird.  It’s still in development, but its name is Robo-Raven.

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois

About the Author

‘BOTS: Robotic Bird Drones – Robo-Hummer – The First Bird-Bot

12 December 2013

[Nano Hummer Video]

On 17 February 2011, DARPA announced the development of the first fully functional robotic bird.  The “Nano Hummingbird” or, as it is also less imaginatively called, the “Nano Air Vehicle” (“NAV”), was the successful result of a project started in 2006 by AeroVironment, Inc. under the direction of DARPA.  Robots, by definition, must “do work.”  And the Nano-Hummer was the first fully functional bird-drone designed and able to perform surveillance and reconnaissance missions.

This robotic hummingbird can remain aloft for 11 minutes and attain a speed of 11 mph.   With a skeleton of hollow carbon-fiber rods wrapped in fiber mesh, coated in a polyvinyl fluoride film, [1] and carrying “batteries, motors, and communications systems; as well as the video camera payload,” the robo-hummer weighs just .67 ounces.

Designed to be deployed in urban environments or on battlefields, this drone is can “perch on windowsills or power lines” and even “enter buildings to observe its surroundings” while relaying a continuous video back to its “pilot.” [video]

In terms of appearance, the Nano-Hummer was, and is, quite like an actual hummingbird.  Although larger than the typical hummingbird, Nano-Hummer, is well within the size range of the species and is, actually, smaller than the largest of real hummingbirds.  With a facade both shaped and colored to resemble the real bird, the Nano-Hummer presents the viewer with a remarkable likeness of a hummingbird.

The Nano-Hummer isn’t stealth in the sense of evading radar.  Nor is it “cryptic,” that type of camouflage that blends, or disappears, into the surrounding terrain.  Rather, with the appearance of a hummingbird, the designers used a type of camouflage called “mimesis,” also termed “masquerade,” as concealment.  A camouflaged object is said to be “masqueraded” when the object “can be clearly seen, but looks like something else, which is of no special interest to the observer.”  And such camouflage is important to a mini-drone with the primary purpose of surveillance and reconnaissance.

Designing this drone on the “hummingbird model,” however, was not done only for the purpose of camouflage.  The project’s objective included biomimicry, that is, biologically inspired engineering. [2] With the hummingbird, its amazingly diverse flight maneuvers were the object of imitation.  However, UAV’s head researcher, Matt Keennon, admits that a perfect replica of what “nature has done” was too daunting. [3] For example, the Nano-Hummer only beats its wings 20 times a second, which is slow motion compared to the real hummingbird’s 80 beats per second. [video] [4]

Whatever the technical shortfalls, this bird-bot replicates much of the real hummingbird’s flight performance. [5] Not only can it do rolls and back-flips [video] but, most important of all, it can hover like the real thing. [video] [6] Hovering allows the video camera to select and observe stationary targets. 

However, this robot’s ability to hover was not developed just for the purpose of reconnaissance and surveillance.   The “hover” of both hummingbirds and bees attracts so much attention from developers of drone technology because it assures success in the most difficult flight maneuver of all — landing.  In fact, landing is the most complex part of flight, and the maneuver most likely to result in accident or disaster.

When landing, a flying object must attain the slowest speed possible before touching down.  Hovering resolves the problem neatly by assuring that the robot can stop in midair and, therefore, touch the ground or perch as zero speed.  Observe the relatively compact helicopter landing port in contrast to the long landing strip required by an airplane which must maintain forward motion when airborne.

This drone has a remarkable range of movement in flight much like the real hummingbird.   Nano-Hummer “can climb and descend vertically; fly sideways left and right; forward and backward; rotate clockwise and counter-clockwise; and hover in mid-air.”  Both propulsion and altitude control are entirely provided by the drone’s flapping wings. [video]

This remote controlled mini-drone can be maneuvered by the “pilot” without direct visual observation using the video stream alone.  With its small camera, this drone can relay back video images of its location.  The camera angle is defined by the drone’s pitch.  In forward motion, the camera provides a continuous view of the ground.  Hovering provides the best camera angle for surveying rooms. [video] [7]

To DARPA, it was particularly important that this drone demonstrate the ability to hover in a 5 mph side-wind without drift of more than one meter.  The inability to remain stable in side-winds was the primary issue with the CIA’s “insectothopter,” a robotic dragonfly was developed in the 1970’s. [image] [8] This unmanned aerial vehicle “was the size of a dragonfly, and was hand-painted to look like one.” [9] Powered by a small gasoline engine, the insectothopter proved unusable due to its inability to withstand even moderate wind gusts. [video]

The Nano-Hummingbird was named by Time Magazine as one of the 50 best inventions of 2011 [10] and has paved the way for the development of a whole generation of bird inspired ‘bots, including Prioria’s “Maverick,” [image] [video] and, the even more “bird-like,” Robo-Raven, which is still in development by the Army Research Laboratory. [image 1] [video] [video]  Also, the development of this first small bird-bot brought the U.S. Air Force one step closer to one of the goals on its wish list: “flocks of small drones.” [11]
And . . . a flock of small drones sounds really cool – as long as the flock isn’t after me.

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois

About the Author



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