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Built up Three more PicPilots

Posted by Brian Wolfe on July 27, 2009 at 1:10am

Well my back ordered parts finally came in so I built up my last three PicPilot boards. I plan on keeping one of them so I'll have two to play around with. One is in my Tri Rotor and the other will be installed in the Easy Star clone I just received. Of the remaining two, I have one potentially sold leaving one up for grabs. If your interested the cost is $375.Thanks,Brian
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What you think about the idea of using quadrirotor UAVs for filming real estate video?

Posted by Hector Torres on July 26, 2009 at 12:48pm
We have a UAV device that can stay on the air for up to 50 mins, runs on clean energy, and supports a payload of 8 lbs. Talking to some companies that sell video to real estate companies, it seems they would be interested in a device like this because it competes against helicopter. The only concern from the people we've interviewed, is stability. I still think there must be something out there to mitigate this concern, right?
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Materials of Interest - TEEK-H Polyimide-Foam/Aerogel Composites for Thermal Insulation

Posted by Khem Caigan on July 24, 2009 at 10:30pm
Polyimide-Foam/Aerogel Compositesfor Thermal InsulationComposites of specific types of polymerfoams and aerogel particles or blanketshave been proposed to obtain thermalinsulation performance superior to thoseof the neat polyimide foams.These composites have potential to alsoprovide enhanced properties for vibrationdampening or acoustic attenuation.The specific type of polymer foam isdenoted "TEEK-H," signifying a series,denoted "H," within a family of polyimidefoams that were developed at NASA'sLangley Research Center and arecollectively denoted "TEEK" (an acronymof the inventors' names).The specific types of aerogels includeNanogel® aerogel particles from CabotCorporation in Billerica, MA. and ofSpaceloft® aerogel blanket from AspenAerogels in Northborough, MA.The composites are inherently flame-retardantand exceptionally thermally stable.Because of thermal cycling, aging, andweathering most polymer foams do not performwell at cryogenic temperatures and willundergo further cracking over time.The TEEK polyimides are among the fewexceptions to this pattern, and the proposedcomposites are intended to have all thedesirable properties of TEEK-H foams, plusimproved thermal performance along withenhanced vibration or acoustic-attenuationperformance.A composite panel as proposed would befabricated by adding an appropriate amountof TEEK friable balloons into a mold toform a bottom layer. A piece of flexibleaerogel blanket material, cut to the desiredsize and shape, would then be placed onthe bottom TEEK layer and sandwichedbetween another top layer of polyimide friableballoons so that the aerogel blanket wouldbecome completely encased in an outer layerof TEEK friable balloons. Optionally, theprocess could be further repeated to producemultiple aerogel-blanket layers interspersedwith and encased by TEEK friable balloons.The sandwiching of aerogel bulk-fill particleswould follow the same methodology or couldbe mixed directly with friable balloons upto 40% weight loading of the aerogel particlesto friable balloons. After sandwiching ormixing of the polymide and aerogel components,the mold, without a top cover, would beplaced in a convection furnace and heated ata temperature of 250 °C for one hour.Then the top cover would be placed on the moldand the temperature increased to about 320 °Cfor between 1 and 3 hours for full imidizationof the polyimide component.The resulting composite should have all thedesirable properties of TEEK, and its effectivethermal conductivity should be less than thatof an approximately equally dense panel madeof TEEK foam only. The heat transfer reductionis directly proportional to % loading of theaerogel component. The excellent structuralintegrity of the foam material is maintainedin the composite formulations.~ Full Article @Nasa Tech Briefs
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Materials of Interest - NASA Langley's TEEK Foam - stable from from -423 to +482 °F

Posted by Khem Caigan on July 24, 2009 at 10:30pm
Keeping Cool in Extreme HeatA new foam knows how to keep its cooleven under extreme high temperatures.NASA's Langley Research Center neededa lightweight foam that could retain itsstructural integrity under temperaturesranging from -423 to +482 °F, for itssecond-generation Reusable LaunchVehicles (RLV).Langley's RLV airframe design requirednew insulation material for the fuel tanks,which are exposed to extreme temperaturechanges over a matter of seconds.Through a partnership with Unitika Ltd.,NASA's Langley Research Center createda foam based on high temperature resistantpolyimide chemistry. The patented foam,named TEEK, is non-exclusively licensedto SORDAL, Inc., of Holland, Michigan.The new low-density foam can be processedinto forms or used to fill structures suchas honeycomb. Also unique is its abilityto foam in place during installation andrepair operations. Most foam must be cutto fit a certain area, and then insertedand molded. This process takes time, andusually a great deal of the product iswasted in the attempt to fit the foam.The new foam is directly applied to theinstallation or repair site, eliminatingthe excess foam that is typically cut awayand discarded.TEEK offers superior insulation and supportqualities, but its greatest advantage isits heat and flame resistance abilities.The TEEK polyimide foam met all of NASA'sneeds and also managed to drasticallyreduce the weight of the RLV.~ Full Article @NASA STI Spinoff
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Materials of Interest - RP46 Polyimide

Posted by Khem Caigan on July 24, 2009 at 3:31pm
RP46 PERFORMANCEWith a continuous operating temperature rangefrom -150ºF to +675ºF and the ability towithstand super-hot spikes up to +1,500ºF,RP46 is ideal for many aerospace applicationsrequiring BOTH weight reduction AND highperformance.RP46 exhibits high mechanical strength andstructural durability at elevated temperatures.It also features significantly less moistureabsorption and is therefore less susceptibleto moisture induced damage.RP46 demonstrates excellent thermal oxidativestability and resistance to microcracking.AvailabilityDesigned as a superior alternative to existingpolyimides, RP46 is available as a liquid forprepreg of carbon, glass or quartz fabric; oras a powder for compression molding hightemperature bearings, slip rings or races.RP46 Polyimide Homepage"Kilogram for kilogram, RP46 is stronger thanaluminum, steel or even titanium."~ from :Thermoset Resinsby K. L. Forsdykeand T. F. StarrPreview@GoogleBooks
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Materials of Interest - Clevios(TM) PH1000 Transparent Conductive Polymer

Posted by Khem Caigan on July 24, 2009 at 3:30pm
Clevios(TM) PH1000 MaterialBreaks Conductivity RecordIt is recognized that the transparent conductorPEDOT:PSS polymer is a key component for theemerging technology of printed electronics.This technology will lead to novel devices suchas printed displays, printed photovoltaic cellsand printed electronic circuits in the near future.In short, PEDOT:PSS provides not only conductivitybut also flexibility combined with a high level oftransparency.Increasing conductivity is the key to opening upthe envelope for printed devices to become a reality.Dr Aloys Eiling, Managing Director of HC StarckClevios commented, "With emerging new technologiesthat require conductivity combined with transparencyand flexibility, Clevios(TM) PH1000 provides yet moretechnical opportunities than ever in OLED lighting andsolar cell applications as well as touch screen andrelated printed electronics uses."As the alternative to the state of the art transparentconductive coatings, mostly based on indium tin oxide(ITO), Clevios(TM) PH1000, an aqueous dispersion ofPEDOT:PSS, provides an easy-to-use solution to moveaway from expensive sputtering methods to wet printingprocesses.Providing crack resistant smooth thin films is a keyadvantage in many applications.~ Full Story @Examiner.com
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Telemetry radio range testing "board" ready for action

Posted by UFO-MAN on July 24, 2009 at 3:00pm

I will start doing some radio range tests across the valley (line of sight) with this "test-board" today. As you can see this is test board #1, and it looks ... well ...The tests will be carried out by car at first. If the tests are sucessfull, the INU will possible become airborne within a few days. First some out of the loop tests, then I will start integrating the DevBoard into the airframe and test some RTL etc.UFO_MAN
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Telemetry

Posted by UFO-MAN on July 24, 2009 at 7:30am


I have now written some initial telemetry code that extracts data from the internal data structures of the r,p,y code running on the UAV DevBoard. The code generates ASCII telemetry frames.

I will later make a binary telemetry frame format for better efficiency. If you have suggestions to the format, let me know. It would be nice to be compatible with the Ardustation.

What I would like to integrate in my UAV system in the future is an accurate height measurement unit (laser, radio, ultrasonic or pressure) as well as an airspeed indicator.

I will carry out some initial RF range testing later today or tonight.



This is fun!

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Successful transmission of rmat data from green UAV Devboard to PC. Visualising with Python visual libary.

Posted by UFO-MAN on July 23, 2009 at 5:30am

I have now sucessfully sent rmat data from William Premierlanis green UAV dev board to the PC and displayed it with the pyton code developed by Brian Wolfe. I tailored the datagrams from the UAV Dev board to fit Brians format so I didnt have to recode the Python code.

Video:



I use a FTDI board attached to the spare serial port of the UAV Dev board. I send data as ints and the python code parses the data and converts to floats by dividing the modified Q15 format by 16384

The yaw axis drifts since the GPS is stationary, however its difficult to see that on this video. The accelleration compensated axes are stable due to the correction from the accellerometers.I have another video that I will post son that shows the drift of the yaw axis better. The yaw drift is no supprise by the way, as this system isn't supposed to give correct yaw information if the plane is stationary as it uses GPS for yaw correction. (The plane may drop to the ground if the groundspeed is zero unless the course is into headwind with airspeed over stall speed).

For a helicopter a three axis magnetic compass may be used for yaw correction. In fact I have a three axis electronic compass intended for use on my four rotor helicopter laying ready for some possible later testing if I get to dig deeper into the code.

(By the way look at the bottom board, not the red one hanging down. The red board is the UHF diversity RX for the telecommand link )

I plan on doing some flight testing with telemetry soon.

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RC Plane Prop Saver

Posted by Robert Drone on July 22, 2009 at 5:01pm
RC Plane Prop Saver: I found this while researching the Super Cub and thought it might be usefull to those of you not flying EasyStars. :From: http://thesmithfam.org/blog/2006/10/17/rc-plane-prop-saver/Direct quote:"Michael Torrie created a really handy tool to save your RC plane’s propellers from a spinning death on impact. It’s called a prop saver and it’s based on the “elastic rules, static drules” principle. Read on for pictures and explanation:The following is a close-up picture of a prop saver:

saver4.jpg

It bolts on to your propeller shaft just like a normal propeller, with two hex nuts (which are barely visible on the left and right of the black plastic yoke). The black plastic yoke is made from an old propeller, with the blades cut off, and two screws drilled into it and, of course, coated with tape for good measure. The tape provides a little bit of friction when you slide the new prop on the top. You then attach your prop onto the tip of the yoke with a rubber band, securing it to the screws like this:

saver6.jpg

The prop sits on the tip of the yoke, swallowing it slightly. The rubber band holds it to the yoke and delivers the rotational force to the prop like a normal nut would, except with a bit more elasticity. That way, the prop’s blades don’t take the brunt of a crash, but rather the rubber band, as this picture shows:

saver3.jpg

That’s one safe prop! You’d have to crash it pretty hard to break it, in which case the prop will be the cheapest repair you’ll make.This approach observes the “elastic rules, static drules” principle by allowing the prop to give a bit, rather than statically absorbing impact forces. This same principle applies to just about every component that break easily."
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new book: RCadvisor's ModiFly

Posted by Carlos Reyes on July 22, 2009 at 3:55pm
How does an original model airplane design get created?I've always wanted to read a book that answered that question. A book that takes me by the hand and shows me how it's really done. One that tells me not just the what and the how, but also the all important why. Since nobody had ever written such a book, I decided I had to do it myself. This is that book.Experience firsthand the joys of building and flying your very own model airplane design. Put into practice the lessons from my previous book, RCadvisor's Model Airplane Design Made Easy. Follow along as we design, build, and fly a modern radio-controlled model airplane.DESIGN GOALSIncorporating the latest innovations and research results, the design is deceptively simple in appearance. However, 20 prototypes and 15 hours of flight testing were required before a design finally met all the goals:* Build it in just one day for less than $5.* A joy to fly with no bad habits.* Sturdy enough to survive hard landings.* Build either a park flyer or an indoor slow flyer.* New pilots can fly it without ailerons.* Easy to build for new scratch builders.* Kid-friendly free flight glider version.* Use inexpensive electric power systems and radio gear.* Great starting point for your own unique designs.You can easily find the construction materials for the airplane at local discount or craft stores. So what are you waiting for?DESIGN PROCESSThe book starts by describing the goals and the long prototyping process that led to the final design. Along the way you get to see firsthand the challenges that creating an innovative design presents. Learn the reasoning behind all the decisions that led to this unique design.A stand-alone book, it is complemented nicely by RCadvisor's online model airplane calculator and my first model airplane design book. Picking up where that book left off, it takes a very pragmatic approach to the entire design process.ADVANCE PRAISE"This is absolutely A MUST READ!" - Bob Aberle"I am so excited about the design that I just have to build one to try it out." - Ken Myers"Carlos kicks out another winner with this one." - Jamie Burke"Even if you have some model airplane design experience, you are likely to learn something from this book. I know I did." - Paul Bradley"Carlos Reyes has done it again!" - Richard Kline"Lots of great info!" - Michael "Crash" Hancock"Carlos' latest book is like a well written mystery novel." - Red ScholefieldSPECIAL OFFERThe book is just $19.95. That is a lot less than the price of a new kit! As a bonus, I'm including a *free* six month subscription to the premium features of the calculator. That is a $12 value! This subscription unlocks the optimizer and all the other advanced calculator features. Current subscribers can extend their subscription for another six months with this offer.FLIGHT PACKAs a service to the RCadvisor community, I'm making available flight packs suitable for the model described in the book. These are the same high quality components I used in all my flight testing:* HXT 5 gram micro servos (4 each)* Flightmax 500 mAh 2S1P 20C LiPo battery packs (2 each)* Turnigy 10A speed controller* Turnigy 24 gram brushless outrunner motor* Slow flyer 8x3.8 propeller* Prop saver and other connectorsThe price is just $74.95, a real bargain. Bonus: for a limited time, I'm adding an extra propeller for a total of two.BONUS STICKERSWhile supplies last, I'm throwing in free high quality vinyl stickers with every order. They are three-inch high copies of the RCadvisor logo in full color. The vinyl is only 0.002 inches thick and is self adhesive. They look great!http://www.rcadvisor.com/productsCarlos ReyesRCadvisor.com founder
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