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Hi all, here is what you can expect from that plateforme with 10 amp ESC and KDA 20/26

Development Update, V4.0 Autopilot from Dean Goedde on Vimeo.

This system sounds promising!

Hello everyone, I'm making a new video game that lets you fly combat drones around in Google Earth and blow stuff up.

Please check out my project page for details.  This game won't get made if drone geeks like you won't support it! Thanks!

https://www.youtube.com/watch?v=4_iRViE67xA

I finally received my Makerbot Replicator (makerbot.com) and I am VERY impressed. After printing a handful of objects off of Thingiverse and dialing in my printer I promptly began work on my version of 3D printed quadcopter. I had a fair bit of practice using Google Sketchup from time is spent designing a handful of tricopters so naturally I started there. Sketchup is a very powerful program for being free and is very easy to learn, however there are some shortcomings to the program when it comes to 3D printing. I'll cover this in later posts but for now I would just like to show you my progress up until now. The incredible thing about 3D printing is how quickly you can prototype a concept. Sketchup is great for visualizing and object but it can never beat actually being able to hold it in your hand and inspect it. You get the feel of it. The weight of it. You can flex it and bend it. To flimsy? Add more material there. Overbuilt? Remove material here. It is simply incredible, a couple of late nights after work and I pretty much have the arms the way I want them.

Using EC3 connections on my quad was a good idea...except when it applied to the AttoPilot 90A sensor from SparkFun. The goal for adding this sensor to the system was to be able to remove it cleanly if needed. The sensor pcb design was changed (from earlier pics in the Wiki) to provide a clean installation of Dean's connectors. What to do? Adapt and Overcome! Behold my solution!

And from the back of the audience I hear "Yeah? So what?" Well the 'what' is the constant challenge we as hobbyists face to take parts and components from different maunfacturers and adapt them to our uses. Have you read the thread on adding this small part? To save you the trouble of looking for it, HERE. Imagine the confusion on the part of the hobbyist who asked if the sensor should be getting hot enough to melt the solder! Wow. The first task I performed after getting a successful adaptation to EC3 was checking for a direct short of the battery connection - none was found. (whew!!) The second task was to insulate the power connections to ensure a short was not added accidently while in use (or crashed).

The solution? Hot Glue! The low temp variety of hot glue guns is cheap and cheap to use. Both sides were sealed off and then tested for mechanical strength. Next was to integrate it into the quad and set it up via Mission Planner. The above linked instructions worked flawlessly to set up the sensor. There is some confusion if you should subtract the 0.3V from the actual measured output from the PDB to the APM. I subtracted it anyway - the MP prompts said I should even if it is contradicted in the Wiki instructions.

The actual function of the sensor can be seen after the APM is reset. It can also be tested with the CLI under the 'tests   -> battery ' command string. NOTE: The CLI prompts you with a "Careful" mesage. THIS MEANS THE MOTORS WILL BEGIN RUNNING! ALL THE MOTORS! I did have my propellors removed prior to making the mod but if you, dear reader, decide to add this and perform the CLI tests.. REMOVE YOUR PROPS.

What you see above is the output of the CLI while the battery test is running. Note that 'Careful' actually blends into the 'Hit Enter to exit' string. When I hit Enter, the screen stopped updating but THE MOTORS CONTINUED TO RUN! I tried various commands from 'exit' to 'Cntr-C' to 'stop battery' all to no avail. The motors stopped spinning when I clicked on the 'Flight Data' icon at the top of the screen. I suspect the command string that is sent to the APM to shift from CLI to Flight Data mode flushed the command registers of the battery test states.

The last part of this tale will be a photo of the AttoPilot sensor as installed on the quad. It is installed prior to the PDB on my system but after the arming plug harness (covered in a previous blog post HERE). Thank you for reading this far and I wish you success should you choose to add this neat device to your system.

Doug Weibel writes:

I just got the most recent issue of IEEE Robotics and Automation magazine, which has a theme of quadcopters as robotics research platforms.  There is a large article describing the various attitude estimation and control algorithms used in Arducopter, OpenPilot, Paparazzi, Pikhawk, Mirokopter, KK muticopter, Multiwii, and Aeroquad.  If you want to know what the difference between what we are doing vs one of the others, this looks like a great resource.

There is also a great article by Robert Mahoney (of DCM fame), Vijay Kumar (from U Penn), and Peter Corke (Queensland U) titled "Modeling, Estimation and Control of Quadrotor".  If you want to review first principles and the math basis for quad rotor control, this will interest you.

Several other interesting articles including one on the interface between autonomous and human control, and another on optical 6Dof Pose estimation.

http://online.qmags.com/RAM0912?pg=21&mode=2#pg3&mode2

It's free and the open source flight controller comparison article starts on page 34. Sample below:

I just want to give a shout about a Kickstarter project that I think deserve some attention.

Basically a well established hardware chip design firm, want's to make a $99 parallel "super" computer and needs help financing mass production to lower the cost of chip production. In return for our support they promise full disclosure for all hardware and dedicated open source development tools.

So for a $99 Kickstarter pledge you get:

• Dual-core ARM A9 CPU
• Epiphany Multicore Accelerator (16 or 64 cores)
• 1GB RAM 
• MicroSD Card
• USB 2.0 (two) 
• Two general purpose expansion connectors
• Ethernet 10/100/1000
• HDMI connection
• Ships with Ubuntu OS
• Ships with free open source Epiphany development tools that include C compiler, multicore debugger, Eclipse IDE, OpenCL SDK/compiler, and run time libraries. 
• Dimensions are 3.4'' x 2.1''  

The reason I am so excited about this, is that this thing is more or less made for next generation autopilots.

- Full blown extended Kalman filter with all the bells and whistles? Would not even break a sweat doing that.

- Real-time visual navigation and object detection? You bet!

- Generate aerial maps on the fly. Be my guest!

You get the idea, and all this would be possible using a 86x54mm board consuming 5W on average. Needless to say I am a bit excited. :)

The $99 pledge is for a 16 core version, but there is talk about a $199 64-core version if they get enough to ramp up the production.

For more information visit the kickstarter here:

http://www.kickstarter.com/projects/adapteva/parallella-a-supercomputer-for-everyone

(More construction photos in link below)

I was flying with an APM2 equipped X525 quad frame but there were a couple of thing I didn't like, namely:

if using a GoPro or other wide angle camera the props would show in the far corners of the video.

Also, orientation at a distance was difficult even with two bright neon-orange legs.

Thirdly, it didn't fold as compactly as I would like for transportation.

Lastly, it looked like all the other X525 framed quads.

So after seeing an H-frame quad on the 'net somewhere I set out to build my own. The first frame was from 3mm ply and balsa using the aluminium arms and feet from the X525 but stiffness was a major issue with motors 1 & 2 sitting higher and at a slight angle while in flight. This caused some strange yaw problems... well, there wasn't any at times, the motor angles cancelling out their yaw effect. I tried covering the ply with very light carbon tissue and epoxy and even some carbon tow braces but could never get rid of the twist between the front and rear arms. A fumbled toggle switch at the wrong moment caused a crash and showed another reason why ply is a bad idea, it breaks very easily!

So...

Next was to find something really stiff and strong, either fiberglass sheeting or carbon, prices were a bit unreal both locally and online, while some suppliers showed no interest at all in selling me any (I'm still waiting for some replies).

I eventually found some 1.5mm woven carbon sheet at Hobbyking but it was only 300mm x 100mm.
The 100mm was fine but I needed 600mm (23") long. This is when an engineering friend came to the rescue (HUGE thanks again, Wladek!), he said I could join 2 sheets mechanically with fiberglass sheet and rivets! So 4 carbon sheets were ordered and some plans drawn up in CAD.

Wladek has some nice machines at his work so we were able to do some very accurate drilling, milling and cutting. 12mm aluminium square tube was sourced locally and milled into a C-channel, saving 1/4 of the weight. Two 0.5mm plastic strips were used to make up the extra 1mm thickness (the X525 arms are 13mm). The carbon is riveted with 3208 rivets to the c-channel.

At first we used the carbon in it's original rectangular shape but we have since cut down the sheet to its present form saving 1/3rd of the weight. If I had to do it again I'd use 1.0mm sheet rather than the 1.5mm saving another 1/3rd. Also initially the ESC's were inside the frame but after many unexplained "ins" and other problems in which I started to suspect an overheating ESC, I have now moved them out into the airflow under the props and all seems well.

Anyway, it flies really well, looks great in the air and fulfils all my requirements, especially no props in the video! (See here). Final weight is 1279g (45oz) dry, with a 3 cell 5000mAh LiPo adding 353g (12oz) totalling 1632g (57oz), about 250g (8oz) heavier than the X525 with the same hardware. Flight time is about 13 minutes. Motors are 20-22L's, ESC's are Super Simple 20A, batts are Zippy Compacts (3S 5000mAh), props are 11x4.7 APC SF.

More construction photos here: Picasa Album

Cheers

link to CAD file>H-Frame2.dwg

HefnyCopter Firmware works in KKv2.1 as in the demo 

https://www.youtube.com/watch?v=55Ab4BfcQss&feature=relmfu

can switch between X-Mode & Plus-Mode.

there is also HefnyCopter2 that works on KK2 it has more new features:

1- BuddyMode where u can train ur friend using another 2 TX at a time.

2- XBEE connection where u can connect your quad to PC.

HefnyCopter is released wheile HefnyCopter is still in final developing phase :)

I made up these hi tech shock absorber legs for my grandsons quad we are building.  Considering the hours I often spend to find a better design for making copter legs that don't disintegrate on every hard landing, It took me about 10 min to stop laughing from the simplicity of the brilliance of this light bulb moment..

T-Rex 450 Test flight -- Loiter / Guided / RTL and Alt Hold

APM 2.0   firmware 2.7.3

MediaTek MT3329  and barometer

After replacing the hidden Torque Tube Bearing in my T-Rex 450 the shifts in attitude are gone.

Everything changed to the best.

I found a great new flying field, so I went to test Loiter, Guided and RTL, Alt Hold worked always great.  I planned a mission too, but the wind became too strong after a while so I will try this another day.

As you can see in the video (thanks to my lovely wife) everything worked very well.

This are the PID  I used.  The Nav speed is low 2m/sec which is relaxing to watch and you have no overshoots.

Thanks a lot DIY Team.

We sent out an email today to all our distributors, if you did not receive it please contact sales@3drobotics.com . We are trying to make sure we have all of you in our distributor mailing list.

thanks

-3DR

Hi, I just watched this video, and it seems to me a good ground base for those who want to start with multicopters and don't know what's the best platform.

I seem to be removing my props often, and I worry that my hand holding the motor while I torque the collett on or off is not strong enough and I certainly don't want to use a steel tool like a Channel Lock.  So, I use a small plumbers strap wrench, pictured below.

This one is overkill because it is made for, well, plumbing.  Specifically for attaching chrome or polished stainless fixtures to pipe stubs without scratching them.  You can find cheaper, smaller and better strap wrenches at Grainger or Home Depot.  In fact, the cheaper the better - you shouldn't have to pay more than $10 for an adequate one.  The benefit of a strap wrench is that it applies pressure evenly all the way around the motor.

Foam Tail Pusher

Range check is always a god idea, especially when using an new rx!
Do not think there will be any more flight test this week due to bad whether, plans are to scale up the frame to host APM.   
My Hitec minima range is horrible 15 m at Aurora 9 Tx at full power I tested whit rx, battery and one servo.

Anyone any ideas?

Project objectives

1. Easy build 2 hour + CNC cutting

2. Dead cheep

3. FPV APM

Anyone else interested in testing the frame let me now.

Here's a source of 3mm standoffs, like the ones under my GPS module.  They are available at any computer store that sells PC parts.  Fry's and Microcenter come to mind.

I accidentally discovered a perfectly fitting cover for my APM stack:

Yup - a cold-cuts box.

I am using a set of thumbscrews to hold my stack to the hexacopter frame , and the cold cuts plastic box fits over the thumbscrews perfectly.  The cover doesn't budge in a hard landing or while carrying the hexacopter.

And it looks cool in the dark.  (Not that I am planning night flying).

New video from ETH Zurich’s Flying Machine Arena, you can read more on Robohub: 

http://robohub.org/video-watch-flying-robots-cooperate-throw-and-catch-balls/

PS. Robohub.org is an online platform that brings together leading communicators in robotics research, start-ups, business, and education from around the world. We just launch the beta version, take a look! http://robohub.org/

We've covered this before, but Hackaday has a good update on the latest ground-based power techniques:

Lasers can no be used to keep a UAV in the air indefinitely. The trick is to add an array of photovoltaic cells specifically tuned to an IR laser’s wavelength. A ground system then directs a high-intensity laser beam onto the aircraft’s cell array to transfer energy while in flight.

After the break you can catch a video from a trade show where a Lockheed Martin employee describes the successful testing of such a system. But there’s a lot more information available in the white paper (PDF) which Laser Motive has released. They’re the folks behind the technology who have teamed up with LM to implement the system. The laser unit on the ground can track a UAV visually, but there is also a method of using GPS coordinates to do so in the case of overcast skies.