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A quick update on Blimpduino: We've temporarily run out of stock at the DIY Drones store but there are plenty at the Maker Shed, where you can buy them at the same price (it's a very cool store--spend some time there!). We've got some components incoming, and I expect to have them back in stock at the DIY Drones store by the end of the month. We'll also be offering the RC and battery + charger option.

We've been recommending the HobbyKing 2.4 Ghz radio for it, but some people have been reporting that Blimpduino doesn't autorecognize RC mode with that radio, due to a slight slower bootup time. So I've modified the code to wait a bit longer for the RC signal and it seems to work fine now.

I've also updated the building manual and operating instructions to make them clearer and easier to use.

All in all, a nice refresh. If you've been wanting to get into UAVs but aren't ready for planes, Blimpduino is a great entry point. Also perfect for winter when you can't fly outside!

We don't talk much about the older commercial autopilots here much, but I was amazed to see the above in my inbox yesterday. The Micropilot 2128g, which is a staple with the university crowd, has only just now upgraded to the 4 Hz uBlox GPS that we in the open source world have been using for years. Weird.

Micropilot's advertising has always bugged me because it's so transparently untrue. Take the below, for example (there are many autopilots MUCH smaller than this; ArduPilot, for example, is 4.5cm by 3 cm):

But Micropilots seem popular with universities, despite the high price. Why is that? It is just a matter of time before the open source IMU-based autopilots, which cost less than 1/10th as much and are closing the gap in performance, take over from these last-gen commercial autopilots in the education world?

Perhaps it's some sort of cruel joke we're not in on but everything I've been able to find on the Internet about tilt-compensated headings from magnetometers leads to this paper [warning, it's a PDF]: http://www.ssec.honeywell.com/position-sensors/datasheets/sae.pdf

In it there is an algorithm for tilt-compensation. It's wrong. Here's what it should be: http://gist.github.com/322555

Ryan Beall is the man.

I thought this was very interesting

http://rcaircraft.blogspot.com/2010/03/wwii-uav-flies-again.html

Another PIC programmer option from Sparkfun, perhaps an alternative to the dubious PICkit III. The $49 Cana Kit says it is "100% compatible with Microchip's MPLAB IDE, and the PICkit 2 interface, and can program all popular PIC 5V microcontrollers including the PIC16F84, PIC16F628, PIC18F458 and PIC16F877."

Connectivity is described this way: "The PIC Programmer offers In-circuit programming through a standard 6-pin ICSP connector as well as a built-in 20-pin ZIF socket for easy programming of any PIC of up to 20-pins right on the programmer. "

Will this work out of the box for the UAVDev Board?

With all the changes and improvements in ArduPilot 2.5, we decided to redo the manual as a wiki on the project's Google Code site. As with all wikis, it's a work in process, but it's now good enough that we have retired the old manual. All the manual links should now point to the wiki.

Please check it out, and if you'd like to make some changes or additions, PM me and I'll add you to the author list.

Here the fuse halves are joined with masking tape and the inch and a half seam tape is applied to the bottom.

Landing gear being molded into the bottom and will be sanded smooth after resin sets. The long brush on top will be used to apply the seam tape to the inside top portion of the fuse.

Rear wheel temporary fit test.

Rear belly hatch used to appy seam tape, later to be used as servo acess.

I realize that this isn't directly relevant to the development of uav systems, but here is a lucky shot I got last week of a red tail hawk in flight. I pulled this frame from a video using VLC player and the camera that I used was a keychain camera I bought on ebay.

Find out what states you track in a 17 state extended kalman filter, what it takes to commercialize a UAV and what hardware object tracking involves.

Reed's profile on DIY Drones: http://diydrones.com/profile/ReedChristiansen