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That's Nathan Siedle, CEO of Sparkfun, handing me the very first ArduPilot Mega board to come off the Sparkfun production line. We were at an Arduino planning meeting in NYC; that's Massimo Banzi of the Arduino project in the back.

Here's a closeup photo of the board. It looks great! The only thing that's not quite right is the GPS connector is supposed to be sideways, so it doesn't rip off in a crash, but we'll fix that in the next batch. It doesn't really matter, because nobody will use that connector; they'll be using the GPS connector on the IMU shield instead.

Front:

Back:

I don't have an ETA on when they'll go on sale, but it's not long now!

Today i flew my Blade MSR using a joystick, my PC, and the 2.4ghz LP4DSM transmitter which used to be in the tx controller. The serial protocol is best documented here, but information on this exists elsewhere including here in a few posts, on diydrones. I'm pretty excited that I finally got this working...it took a few nights of serious head scratching to work out some kinks.

I used a USB to TTL breakout board to transmit to the LP4DSM module, which apparently is a pretty common module found in numerous spektrum and other transmitters. I used LabVIEW to assemble all of the code, pulling axis information from the joystick, filtering this data, and converting that into hexadecimal PPM which was sent via serial to the TX.

I still have some bugs to work out, but it worked, and that is progress.

So, while I was working on this, I also bought an Arduino Pro Mini (yes, i gave into the temptation of a $20 already tested, super small, and assembled board :-D ) and an "ArduIMU Sensor Board - Six Degrees of Freedom (Main)". I put the board name in " " because it's actually only 4 degrees of freedom, having a 3 axis acc and a 1 axis gyro, with analog output.

It doesn't come with any documentation (nor does the Arduino Pro Mini), and I'm not sure if that is common or not. There is online documentation for the Arduino Pro Mini, which is helpful, but I find the information here on DIYdrones to be the best resource. thankfully the hardware is somewhat self explanatory.

Lastly, I bought two micro servo boards, which are the same servos on the Blade MSR, and the BMCX, and possibly others. i'll have to post the name/details of those servos later, i can't find the info right now.

My plan is to put both boards on my MSR, to make a stabilized camera mount using my endoscope vid camera. You can see where this is going.... :-D

....pull off the 5 in 1, add 2 more servos and a rx, and I should have a blade MSR that can be video camera flown, flight stabilized, and hopefully very, very cool. (and hopefully light enough!)

As some people might know there is a team hard at work on OpenPilot and we are making some progress, like every complex project things don't go as fast as you like but progress is happening. One of the things we are working on now is the low level infrastructure for the AHRS, this makes it so our EKF developers can just drop their code in without messing with the low level side of things.

On of the issues we needed to resolve was filtering the inputs, we were a bit unsure on which way to go. I sent an email to Caleb from CHR to ask his advice, he not only helped a lot but also gave us permission to use parts of his gyro filtering code such as his FIR filter as long as we credited him. Naturally he will be credited in the code and the credit file but I wanted to say a public thank you for this as well.

What I love about OpenPilot is the community, this side was mentioned on the podcast where we announced the project. Caleb is a perfect example of this community spirit.

Additionally, I don't see the CHR-6dm AHRS mentioned much here, so if you are looking for a well priced, powerful AHRS with a complete EKF have a look at http://www.chrobotics.com/ - Caleb rocks :-)

A small update on OpenPilot as well. Things are moving along, we have our issue tracker running now which can be found at bugs.openpilot.org there are still tasks to be added as not everything being is done is in there yet but it will be. There is a burn down chart which shows how far away we are from the version 1.0 release and a list of outstanding tasks that we need help with if people want to get involved.

Have you asked yourself "It would be great if I could get this part, but smaller" or "i could use this but it needs extra flanges or tubes or whatever" then you're in luck

http://www.emachineshop.com/

check it out - you get instant part price quoting from the ***FREE*** CAD software program

A little patience goes a long way!

BaroneOSD is a PAL video overlay impression WITHOUT additional hardware required (NO LM1881 Sync generator).

Use only 3 pin:

D1 (USART TX) used to pump pixel in the video connected with a 330Ohm resistor to D6

D6 (AIN0) Video in/out, connect here you camera or radio TX.

D7 (AIN1) 0.3V Voltage reference (you can use a partitor resistor)

Jason Short and I had great day of testing and improving code (and putting in a pretty good T3 contest time!). Once again we were at the RC club in Point Richmond, across the Bay from San Francisco. Jason was just back from a skiing vacation where he tangled with another snowboard to the tune of 17 stitches on his ankle (I saw them: ouch) but fortunately UAV development doesn't require a lot of running.

You can see what flight testing looks like above. I fly, he watches the telemetry and then makes changes in the code for me to test.

Here's the rundown of the day's progress. You should see all this reflected in the code in the repository in a day or so:

The Good:

--Navigation is now locked in pretty well. Straight lines to waypoints (no more snaking) and pretty tight turns between them.

--Manual throttle control now works in autopilot mode! Just like you can "nudge" the plane's direction with RC controls while it's flying autonomously, you can now speed it up or down. Excellent for finding the best speed for T3 runs!

--The funky thing with one of my Futaba FASST receivers working and the other not was solved. Turns out that one of them outputs the PWM on all channels in serial, and the other in parallel. Who knew? Anyway, ArduPilot can handle either. If your radio does something weird like only letting you fly left, not right, edit this line in the config file:

//3-2

#define RADIO_TYPE 0 // 0 = sequential PWM pulses(Fasst, Spektrums), 1 = simultaneous PWM pulses (Corona RP8D1)

--We flew the FunJet in RC mode (although it has an ArduPilot, we haven't set up elevon mixing yet). Amazing performance: fast, rock solid and incredibly maneuverable. Once we get it dialed in with the AP, we're going to be looking at sub 10 second Sparkfun runs ;-)

The Bad:

--We still don't have altitude hold working right. We finally got it to display the right altitude in the ground station, but for some reason it's not holding. Jason thinks this is just a matter of tweaking throttle and pitch gains, but for now I had to trim the pitch down manually for the T3 trial runs just to ensure the plane didn't get too high during the autonomous portion.

--We're getting different results with different sensors. I'm flying with FMA sensors, and Jason was flying with DIY Drones sensors. The calibration routines should mean that as long as you've got a matched pair it shouldn't matter where they come from. But for some reason it still does, and different sources require different gains in the code. We'll figure out a way to make that go away...

The Stupid:

--I almost crashed one time by launching with stabilization accidentally on, but not yet calibrated (it takes a few second to calibrate in the air). Also we found that if you happen to power on in stabilization mode, it messes up your waypoint settings (for some reason it thought it was starting on waypoint 7), so for now just don't do it until we can find and fix that bug.

--I also almost crashed launching downwind. In my defense, the wind shifted direction. But still!

--I nuked another Xbee by powering on with the signal line attached. I can rescue it, of course, but I CAN'T WAIT for ArduPilot Mega to make this problem go away with the dedicated serial lines.

Variable Pitch Quad Rotor - M/UAV

DIY project ranging from a 600cc 120HP etec Ski-Doo engine, UltraSport 254 tail rotors, extruded aluminum blades from Vortech, aluminum / steel tube structural components, and a carbon fiber reinforced polymer monocoque frame.

From a Der Spiegel UAV photo gallery. Note the over-the-top caption. What is this toy plane? It looks like a Hobbyzone Phantom!

I've been fascinated by optical flow ever since I learned that you can do some pretty good navigation work with the chip taken from an old optical mouse. I think this is probably going to be one of the methods we use to take Blimpduino navigation to the next level (it's ideal for any unknown environment, as well as GPS-denied ones). As the picture above suggests, optical flow is the method that many animals, especially insects, use to navigate in complex space.

Here's a writeup from Hizook about the latest research in the field. The authors describe the advantages of this technique:

"The main benefit of this method is that the information about the optics and scene depth is wrapped into a model that is easily learned from video from the robot. No calibration grids or complicated lens distortion models are required! The primary limitation from a practical standpoint is the assumption of constant scene depth, which would break down if, for example, the robot turned to directly face a very close wall, departed from the ground plane, or moved from a narrow corridor into a large open area. "

Here's a video that shows how it works:

CVPR 2009 from Richard Roberts on Vimeo.

[Fly image at the top from the Max Planck Society]