Tom Rearick's Posts (3)

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5334390301?profile=originalNewly emerged virgin honey bee queens become inseminated in flight by multiple male honey bees (drones) in elevated regions called Drone Congregation Areas (DCAs).  These DCAs are areas five to 60 meters above ground and 30 to 200 meters in diameter. They can persist in the same place for dozens of years - longer than the life of any queen (a couple years) and much longer than the life of a drone (21-32 days!).   This raises a question: How do queens and drones know where the DCA is year after year.  Since drones and queens arrive at DCAs from multiple colonies, it is believed that DCAs exist so that queens can maximize the genetic diversity in their colony.  Somehow, they all know where to go to link up.

 

To try to solve this mystery, DCA research has traditionally used helium balloons dangling pheromone lures to locate DCAs. It is slow and tedious work. In 2015, I wrote about multirotor pilots encountering DCAs in a blog post called "Drones Make Love Not War" (http://www.beehacker.com/wp/?p=1243).  In that posting, I linked to several YouTube videos showing 'angry' bees that I pointed out were really just horny bees.

 

My good friend and UGA Master Beekeeper Julia Mahood has created a website (http://mapmydca.com/) for multirotor pilots to report DCAs they encounter.  If you are willing to search for DCAs, she provides plenty of information to get you started.  If you are not a multirotor pilot, you can help our research by forwarding this post to someone who is a multirotor pilot.

Thanks for your support.

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Drones Make Love Not War

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I have two hobbies: beekeeping and building/flying multirotors or drones. There is rarely any overlap between the two but recently I have noticed a spate of YouTube videos with titles such as:

Some of these videos are picked up by the media and further sensationalized. Too bad they all get the story so wrong. These bees, drones actually, are not angry. They are simply horny and they think they found a virgin queen worth dying for.

For those readers new to honey bees, I offer this quick summary of honey bee biology. Honey bees have three castes or forms: sterile females or workers, males or drones, and typically a single reproductive female or queen. A queen's job is to lay eggs. She can lay up to 1500 eggs a day for several years. But first, she needs to copulate with about 12 (plus or minus 7) drones because she will never mate again once she starts laying eggs. Drones are flying penises. They carry genetic material. That's about all they are good for. They don't even have stingers like the girls do. Most drones will never mate with a queen but when they do, they do it in the air, the drone has his gonads ripped out of his body, and he falls to his death. Satisfied, I hope. The workers handle every other task: feed the queen and growing larva, put away honey, build out wax comb, fill cracks with bee glue, take out the dead, guard the entrance, warm or cool the inside of the hive, and forage for food.

What all of these videos show are drone congregation areas or DCAs. These are areas where drones from different colonies gather in hope of mating with a queen. A DCA is typically 10-40 meters above ground with a diameter of 30-200 meters. The utility of a DCA is that it provides an efficient way for a queen to acquire genetic material from outside of her own colony. Inbreeding is bad for any species.

DCAs have been known to persist in one geographic location for 12 years. This is curious because drones do not survive the winter as workers do (the girls kick their brothers out of the hive each Fall) so there must be something intrinsic in the area itself to attract drones from multiple colonies to the same place year after year. Yet another honey bee mystery waiting to be solved.

Drone congregation areas are not rare but their discovery is rare. They are normally discovered in urban areas by observing a number of dead drones on the concrete or asphalt. Balloons and kites with suspended nets and pheromone lures have been used in the past to study DCA but perhaps multirotors could offer a better research platform, eh?

How can I be so sure that these videos are of drone congregation areas?

  • If you step through frames, you will see that these bees have rounded bottoms - that is the stingless abdomen of a drone.
  • Workers have no reason to congregate above tree level because there is no food there. They may fly above tree level to reach a nectar source 3 miles distant but they do not tarry nor do they travel in packs.
  • I know, I know, that's not what happens in the movie "Deadly Bees" but honey bees away from their colony are not aggressive. They will defend their colony and themselves but they do not attack unprovoked. Honey bees are vegetarians, for Pete's sake.
  • The buzz of a multicopter may attract the horny drones in a congregation area. But I have flown my multirotor within a few feet of three busy hives - seeking to solicit a response - but the worker bees showed no interest or aggressive behavior at all.

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Wire Legs for Multirotors

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A really useful multirotor is big enough to carry a camera or FPV yet small enough to take with you everywhere. A quad or tri rotor can be made more compact by folding the arms but how about some legs that fold out of the way? As soon as I saw the Qube H-copter from Aerovironment, I knew I had my answer. I like the Qube's wire legs for several reasons:
  • they fold flat
  • they are strong & lightweight
  • they have a very small cross-section to the wind
  • they are reliable. There really isn't anything to break...bend maybe.
The Qube mounts folding wire legs to round arms using custom plastic collars. But I wanted to attach my wire legs to 1/2 inch square pine arms. The first two photos shows my solution. Two tie wraps hold each of two identical custom hinges to the wooden arm. No holes are drilled into the wooden arm itself so its structural integrity is not compromised. One hinge pivots a custom cross arm and the other hinge pivots the 5/32 inch diameter piano wire leg. The end of the legs have rubberized ball feet made from a bead of JB Weld surrounded by a 1/2 inch ball of OOGOO. You could also use Sugru.
You could make these legs a lot shorter. As it is, this tricopter will bounce like a ball on a hard landing. I have not broken any custom parts yet.
Where does the custom hinge and cross arm come from? From 3D printers at Shapeways.com. I drew both parts in the free version of Sketchup 8 in one night and spent another night preparing (debugging) the designs for 3D printers. The requirements for printing 3D objects are much more demanding than requirements for simply rendering a pretty picture. I used both MeshLab and NetFabb Studio. The Shapeways website has all the information you need to get and use free or open source 3D design software.
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A single set of 2 hinges and one cross arm will cost you about $14 in materials at my Shapeways store. I offer the design for free - I do not know if it is protected by any patents.
The $14 is not bad for a precision prototype but too expensive to use on a regular basis.  In my next post, I will show you how I made a silicon rubber mold from these 3D printed parts and knocked out strong epoxy parts for pennies.
Build log
3689514390?profile=originalA little background on this tricopter. I have an APM1 quad and a KK2 quad but this smaller 3DCC tricopter is great for sport flying because its yaw response is so good. It weighs - with an 800mAh 2S battery (but no camera) - 17 oz and flies for about 5 minutes. It flies faster, longer, and warmer with 1000mAh 3S battery but is still very lightweight. I keep my pockets filled with charged batteries.
The thing I like best about this tricopter is that it crashes into trees and falls out of the sky (a lot) but it rarely breaks anything more than a propeller (if that). I spend more time flying (aggressively) and less time repairing.  I fly HD video cameras and FPV with it.
Frame laser cut by Ponoko from Improved RC Explorer pattern by colorex.3689514413?profile=original
1/2 in. square pine arms, 10.5 in. long
3x 8045 slow fly propeller
OpenPilot 3DCC
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