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"World's First Single Chip 3-Axis Digital Gyroscope"

Posted by Angus Peart on October 27, 2009 at 12:30am
Check it out:http://www.prweb.com/releases/2009/10/prweb3108684.htmhttp://www.invensense.com/products/itg_3200.html

gI_0_InvenSenseITG3200.jpg

$3 in mass volume, so that has to mean under $20 single quantity.16bit digital output using I2C Interface is nice, 16bit is a good start.Sadly if it's anything like the IDG range it will never compare to "serious" gyros like the AXDRS range. It's a start though.
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3D Robotics

Huddle Workspace updates and bug fixes

Posted by Chris Anderson on October 26, 2009 at 8:30am
For those on the DIY Drones development teams, you may have noticed a few updates on Huddle. Formatting now works so your paragraphs will break properly in discussions. The >1MB bug in editing documents has also been fixed, so you should be able to edit online without fear of changes not being saved. Currently, Huddle only supports Firefox and IE7+ on Ning (apols to those using Safari, but not to those using IE6--upgrade!). If you want more powerful and flexible editing and collaboration tools, you can work on huddle.net instead. Just create a free account there and click on "Link existing Huddle.net account" on the top of the Ning workspace.
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3D Robotics

More cool micro UAV platforms--monocopter and VTOL

Posted by Chris Anderson on October 26, 2009 at 7:44am
From BotJunkie: "The University of Maryland monocopter can take off from the ground, hover, fly controllably, and land without killing itself. The key was a lot of research into the flight characteristics of the seed pods themselves, which enables the monocopter to autorotate just like the real thing. Obviously, the camera isn’t really useful for surveillance at this stage, but that’s solvable. Researchers suggest that the craft could be airdropped, autorotate for a while, and then be controlled remotely for “defense, fire monitoring and search-and-rescue purposes.”" And also from BotJunkie, "a prototype of a micro air vehicle called AirBurr that comes from the Laboratory of Intelligent Systems at EPFL. The version in this video is a remote controlled prototype, but the design is intended to be autonomous, with robust collision recovery in indoor environments. AirBurr is a sort of cross between a helicopter and an airplane, with a bunch of airplane style control surfaces and a horizontal plane lifting rotor like a helicopter. "
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Ublox to nmea converter

Posted by Jesus on October 26, 2009 at 4:44am
Hello:I want to use a ublox gps for two item. A paparazzi autopilot, that need a ublox gps, and a osd that need a nmea code gps. And I want to use only one gps. Is there any kind of ublox code to nmea converter? O something like that?ThanksJesús
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Closed loop autopilot simulation with FlightGear - Part 2

Posted by Faisal Shah on October 25, 2009 at 11:02pm
Figured out how to close the loop!Programs can interface with FlightGear through FlightGear's property tree. Very powerful.http://wiki.flightgear.org/index.php/Property_TreeIf you run FlightGear with the --httpd= option, it will run a webserver on http://localhost: where you can browse the property tree and refresh the current values. Alternatively, in FlightGear you can type "/", and the property tree viewer will pop up and you can view the values changing in real time. I did this to figure out the sign convention for different properties.The property tree can be read from and written to using a "Protocol". The protocol basically defines the format in which data is exchanged. You identify the nodes in the property tree which you want to interact with, the data types, the string formatting, and voila! Attached are the input and output .xml protocol files which I used (copy to FlightGear's data/Protocol directory).The data can be passed through several means, serial port, tcp, udp, etc... I chose UDP for ease.Here is how I ran FlightGear:fgfs --httpd=5500 --generic=socket,out,40,localhost,5000,udp,output_protocol --generic=socket,in,45,localhost,5010,udp,input_protocolI made the input data rate faster than the output data rate, because I would rather have FlightGear waiting for a new input value (when it doesn't get a new input, the last one persists) than the input being buffered.The --generic option allows one to specify a generic protocol, which was defined in the .xml file (attached).--generic=socket,,, ,,,.Attached is a .c program which I wrote to interact with the property tree and provide feedback controls to FlightGear. I've implemented simple proportional control for roll and pitch to stabilize the aircraft. Timing is driven by FlightGear. The code makes a blocking call to read UDP data. It waits until it receives a new packet, processes it, and sends a packet with control inputs back to FlightGear. Then it loops again, waiting for another packet from FlightGear. Currently, everything is hardcoded (port numbers, etc ..), but it should be trivial to make it more general purpose.This should provide a complete framework with which to write an autopilot controller in C.Comments please!udpserver.coutput_protocol.xmlinput_protocol.xml
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Moderator

AscTec Falcon 8

Posted by Gary Mortimer on October 25, 2009 at 10:24pm

falcon8_1.jpg

Very lucky last week to get the chance to fly one of these fantastically scfi machines. The chaps were over from Germany on a UK tour and I somehow cracked an invite.

Thats all of us looking very serious, I think an important thing to note is that there were four real helicopter pilots there!

That's the venue.For 18,000 euros you certainly get a capable machine that was very easy to fly in some wind, it was at least 15 knots above the trees and the machine just stayed pinned where you left it in the sky.I took the chance to maiden a slightly different Manta as I think I may have mentioned elsewhere ;-)

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3D Robotics

DIY Drones live chat/podcast tonight at 10:30pm PST

Posted by Chris Anderson on October 25, 2009 at 2:56pm
Free video streaming by Ustream Tonight (Sunday) we'll do our regular podcast, which everyone here is welcome to participate in by listening to the chat live above and commenting and asking questions via the DIY Drones chat function. We'll be starting at 10:30 PM PST, to accomodate the time zone differences with out guest, and will probably go about 40 minutes. This week we'll by joined by Gary Mortimer, talking about the stunning Ascending Technologies Octocopter, his own UAV experience and potential UAV use in Africa. Other themes will include --Progress on DIY Drones projects --The VectorNAV IMU --The winner of the T3-2 contest --Favorite blogs posts of the week --And whatever other cool stuff comes up!
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SECRETS OF THE C328

Posted by Jack Crossfire on October 25, 2009 at 4:00am
C328 product page

Finally a UART camera you can multiplex with telemetry. It's a way of getting live preview video without the insane price of 900Mhz video or the bandwidth conflicts of 2.4Ghz video. With 2 Xbees & a computer to control it, it's the cheapest video downlink you're going to get.

For you Xbee fans, the maximum camera packet size is limited by the XBee buffer size to 128 bytes & you have to send an ACK after every packet, thus the XBee latency slows it down by 1/3. Highest performance would take a local microcontroller with full flow control to send the ACKs.It's pure hell to get initialized, but once it starts, it keeps working. Normally just getting it started entails sending init commands, failing, & waiting 10 seconds over & over for several minutes. If it's interrupted in the middle of an image transfer or the serial port glitches, it takes a lot of long waits & init commands to get it to work again.Sleeping around 1/4 second between the snapshot & getpicture commands is required to avoid nasty image corruption, but the JPEG compression is otherwise instantaneous.The lens is really loose, so you'll need to tape it for flight.

Dual radios for autopilot & video.

Ground station for video. Buy a proper XBee breakout board from your sponsors instead of doing this.This is a video of the UART cam in flight. The picture quality is so bad, 160x128 is probably the only resolution you need for preview video.This is a program for getting video off it.video.cNow some benchmarks.JPEG, 128 byte package size, & bare Xbees640x480 (48kb) =15 seconds per frame320x240 (20kb) =7 seconds per frame160x128 (2kb) =1.2 seconds per frameXBees + local microchip generating ACKs640x480=10 seconds per frame320x240=5 seconds per frame160x128=0.7 seconds per frameUSB serial connection & 128 byte packages640x480=11 seconds per frame320x240=5 seconds per frame160x128=1 second per frameUSB serial connection & 512 byte packages640x480=6 seconds per frame320x240=3 seconds per frame160x128=0.7 seconds per frame
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Remzibi OSD USB to Serial Cable and FTDI cables are interchangeable!

Posted by Paul Mather on October 24, 2009 at 7:30pm
I did some testing this evening with the FTDI cable from DIYDrones, the FTDI cable from SparkFun, the OTI USB to Serial cable from Remzibi's OSD and the Prolific USB to Serial cable that Remzibi is going to start shipping with the OSD's.Turns out the FTDI's can be used to program the OSD and Remzibi's cables can be used to program the ArduPilot (with a little modification).To use the Remzibi cable on the ArduPilot, you'll need to cut off the shrink wrap where the wires go into the silver braided cable and expose the green, brown and orange wires. The orange isn't used (or soldered to anything internally). Use the wiring diagram below.Remzibi_Cable_To_ArduPilot.gifTo use the FTDI cables to program the OSD, you'll only need 4 wires. Use the diagram below.FTDI_OSD_Cable.gif
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Huddle Issues Anyone?

Posted by Scott Plunkett on October 23, 2009 at 1:26pm
I have been trying for a while now to get into / see the Turn Rate Limiter Workspace in the Workspaces section...but it doesn't come up...I am on two teams, and can only see the Workspace for the New Ground Station Design team. Anyone else having similar issues - or did I get kicked off the team...lol ;)I have the uBlox GPS Module library part I need to upload.
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Modularity, Versatility, Affordability

Posted by Wendi Smol on October 23, 2009 at 1:08pm
Here I have drawn some ideas of how to arrange wing and fuselage (shoulder wing or "middle" wing. There is also the possibility of adding a bottom pan to the underside of the fuselage to create a water plane for the water lovers. At least you have a chance to rescue your expensive equipment after a dunk. Undercarriage can be either left off or fixed depending on your take off ground; I will make a retractable UC as well (for the high speed runs :-)).

Long span wings are planned for more range or flying time. Up to the span shown no further changes are necessary, Spans in excess of 2m will require a fuselage extension as well. This may even be done as an afterthought.

Here I have tried to give you some ideas of how to mould the front fuselage. Anything you dont like on the original you can just cut off and graft a new front end of your own design and suitable for your requirements. The room available is about two cubic decimeter (the large plastic milk bottles in UK, don't know about the USA)

And if you partout dislike FANS you can fit a motor with PROP, I may do that myself probably just to find out.

This is the ultimate for the avangarde. If you like wings only or tailless flyers this is the thing. It may even have real advantages. But to find out I have to do some more arithmatic.

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