Blogs

All Posts (14048)

Sort by

Turn Rate Limiter Shield Preview

Posted by Jeff Taylor on January 21, 2010 at 2:00pm
This is the first working version of turn rate limiter starting beta testing now!For those not familiar, this is a project aimed at providing a cheap, easy to use shield for beginners. It only requires this board and the ArduPilot main board to fly the plane, very simple!

I got only a mild version of Jordi fever, only the pressure sensor was affected :D

That gyro is so small!!!
Read more…

XDuino - 32Bit ARM-7 Cortex-M3 MCU with Arduino-compatible syntax and similar IDE

Posted by Jonathan Lussier on January 21, 2010 at 10:52am
Website: http://www.xduino.comPrice: 30$ + 10$ shippingInfo:http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1248633489http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1247691841http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1257646436I think this board would be a great replacement for the arduino, esp in tasks such as ardupilot, arduimu, etc where limitations are present (ie Kalman filters are too slow, ROM is too small, etc). A huge benefit here is also that there are two DACs (not PWMs, real DACs!) and not only that, but they're 12-bit. The ADCs are also 12-bit, compared to the Arduino's 10-bit ones (and there are 16 ADCs vs. 6 on the Arduino).This board is SMT only which I think is reasonable (and lighter weight as well).The board features: (from the website)Bootloader via RS232 (not USB) (which saves weight)32Bit ARM Cortex-M3 running at 72MHz 64Pin (LQFP) by STmicroelectronicsUse Crystal 8.00MHz + Phase-Locked Loop (PLL) - computes at 1.25 DMIPS/MHz to process data that is equivalent to 90MIPSHas RTC (Real Time Clock) Circuit with XTAL 32.768KHz and Battery Backup connector5 Serial ports48 General purpose input/output pins (GPIO)16 Analog input channels 12-bits (ADC)2 Analog output channels 12-bits (DAC)512 Kbytes of Flash memory68 Kbytes of RAM3 SPI ports (2 can do I2S)2 I2C1 USB1 CAN1 SDIOSupports In-System Programming (ISP) and In-Application Programming (IAP) through On-Chip Boot-Loader Software via Port USART1 (RS232)Has RS232 Communication Circuit that uses Connector 4-PINHas 48 Bit GPIO with 5V-Tolerant for independent digital applications (maximum analog input is 3.3V)Use +3.3V Power SupplyConnectors is placed on 50 Pin Header with a distance of 2.54mm (100mil) (25 pins per side) with a distance of 1.5 inch (1500mil/38.1mm), so it is quite easy to use and expand I/O Circuit.Any thoughts?
Read more…

Stabilization of RC Helicopter with NeuroFuzzy networks

Posted by Aldo Vargas on January 21, 2010 at 9:30am
Hi everybody!!!I'm making a stabilization system for a helicopter, hehehe, another one...First of all i want to show my hardware:- ArtTech Falcon 3DRotor Diameter: 24.8"Tail Rotor Diameter: 5.98"Weight: 19.5 oz.Length: 26.4"Servos: 4 9g servosTransmitter: 6 channel 72MHzReceiver: 6 channel dual conversionBattery: 3S 1300mAhr 10C LiPoMotor: Brushless B20/10TESC: 18A Brushless

- The great Arduino as Avionics- IMU 6DOF Razor ( http://www.sparkfun.com/commerce/product_info.php?products_id=9431 )- Small arduino shield build by me, just with the purpose of holding and connecting the razor to the arduino.Software:- DCM modified by Automatik, 10x a lot man!!! ( i had made some modifications, for making the arduino control servos for pitch and roll)- LabView VI made by Automatik, 10x again man!! ( with a little bit of modifications )What have i done so far:- I've had a lot of problems with vibration!!!! its the thing that had stop everything!!!- We try several configurations, with foam, and other stuff.- The configuration that work the best, its a base with rubbers and velcro, a little hard to explain in english, so ill just paste a picture....

In this picture, the heli is showing the base, and you can see the rubbers.

You can see the shield and the arduino, mounted inside the landing gear.

You can see the usb port, its on the back of the heli.

I just uploaded a video, with the first test with the rubbers and velcro, sorry, its in spanish, because it was for my faculty advisor, hehehehehttp://diydrones.com/video/instrumentation-with-rubbersVibration Issues:In the next pics you can see the problems i had with the excesive vibration produced by the helicopter, and this issue make the stabilization impossible!!!! Because the angles are completly crazy!!!This test was conducted with the DCM filter and half throttle.

This test was conducted with the kalman filter and half throttle.

What do i want right now??In this moment i just want to focus on stabilization, and mainly in pitch and roll, i will not take care of yaw...Any help, comment will be greatly appreciated!!!10x a lot!!Saludos!!
Read more…
Developer

Replacement for the SuperStar EP Select

Posted by Doug Weibel on January 21, 2010 at 7:19am
The Hobbico SuperStar EP Select is one of the two recommended airframes for ArduPilot and it has been a good choice providing a nice "high wing aileron trainer" at an affordable price. Unfortunately, it has been discontinued for some time and a recent check finds them near impossible to source any more.I have looked around for an equivalent replacement. One I found suitable is the Hobbico NexSTAR Mini EP, which is more or less Hobbico's replacement for the SuperStar EP Select.

lhcaa0700.jpg

It is sold either as a ready to fly package with a 2.4 Ghz radio or as a receiver ready package. Tower Hobbies has these two for $270 and $180, respectively, and Tower usually has a coupon out which will give you $15 to $20 off. Just google "tower hobbies coupon discount". Replacement fuselages, wings, and tail surfaces are also available. While the receiver ready price is 50% higher than what we were paying for the ARF Superstar, the inclusion of a brushless power system and servos makes the price a reasonable value.I received a receiver ready kit today and have inspected it. Apart from the covering being a bit wrinkled, which I think is a Hobbico trademark, I am pretty happy with the quality. See pics below comparing the SuperStar and NexSTAR.While it is nearly as long as the SuperStar and has just a bit less wingspan, the chord is substantially less and the weight is substantially less. Since it is designed for a brushless/LiPo power system the reduced wing area is appropriate. The fuselage width is adequate for UAV purposes. You can see the Mega board inside the fuselage in one pic below.Things I like:* It is a "receiver ready" kit, so it is very complete. About all you need to fly it is a TX, RX, and battery.* Fuselage is plenty deep so no issues with interference between AP gear and the aileron servo arm and pushrods* The wing ribs all have lightening cutouts so fishing a pitot line to the outboard leading edge will be much easier.* Steerable nose wheel, servos, brushless motor and esc all come pre-installed.* A good wing attachment system using a nylon bolt and a fitting that allows flex in a crash.* Reported flight times of 15 minutes on a 3 cell 2100 mAh LiPoThings I didn't like:* A balsa shelf will need to be added for the AP as the shelf for the RX is small. An additional shelf will provide a nice large area for the AP, but it will be under the rudder and elevator control rods so hooking up wires will be a bit fiddly.* A little smaller than I expected.I am short on receivers today, so I probably won't fly this for a week or so, but will post comments when I do.

Read more…

Podcast Episode 14 - Henri Seydoux, CEO of Parrot (makers of the AR.Drone)

Posted by Tim Trueman on January 20, 2010 at 9:47pm
iTunes linksAAC: http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=330632997MP3: http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=330633212RSS feedAAC: http://feeds.feedburner.com/diydronesMP3: http://feeds.feedburner.com/diydronesmp3Henri Seydoux is pronounced "On-ree Say-doo" (I believe, correct me if I'm wrong).
Read more…
3D Robotics

Congrats to the winners of T3-4!

Posted by Chris Anderson on January 20, 2010 at 3:55pm

The High Chief T3 Judge, Gary Mortimer, has ruled, and the above are the results of T3 Round 4, photo-mapping a quarter kilometer. Brakar was the overall winner, but everyone listed did a great job. A very impressive crop of entrants--congrats to you all. Because all the submissions were excellent, everyone will get a prize of some sort, but the grand prize will be an ArduPilot Mega beta unit. (This is either a blessing or a curse, depending on how many bugs we find on those boards. But so far, it's looking pretty good)
Read more…
3D Robotics

T3-Round 5: Virtual Sparkfun competition!

Posted by Chris Anderson on January 20, 2010 at 2:00pm


For the fifth T3 (Trust Time Trial) contest, we've got an easy and fun one: set the best time for a virtual Sparkfun Autonomous Vehicle Competition course. The real Sparkfun contest will be held on April 17th in Boulder, Colorado, and is simply the fastest time for an autonomous vehicle to do one lap around the company's headquarters (shown above). The DIY Drones team won it last year in a time of 35 seconds, and we (and other DIY Drones community members) will be entering this year, too.

Your mission is to program your UAV to fly a pattern around a rectangle the size of the Sparkfun HQ (dimensions shown above). One lap, fastest time wins. The rules don't say anything about takeoff or landing, so you can cross the start line (shown in the picture) at full speed and it doesn't matter what happens after you cross the finish line. Altitude is up to you, but stay below 400ft, as always, and I'd recommend staying above 100ft to avoid the evil trees!

I expect that competition will come down to fractions of a second. Since most GPS loggers only record a position once per second, you'll need to interpolate between timestamps for both the start and finish time. The way to do this is to draw a line from the pointy bottom tip of two adjacent Google Earth pushpin markers. Estimate how far along that line the start or finish lines cross, and apply that fraction to estimate the real time. This illustration gives an example:


Please show these calculations on your KML path image.

BTW, it would be cool to have a model of the Sparkfun HQ to place in Google Earth so you can display your path around a "real" building. Your Chief T3 Judge, Gary Mortimer, has issued a call for a volunteer to make that model, so when one of you rises to the challenge I'll post it here for all to use.

Same submission rules as always. Submit time, autopilot and airframe, and KML track (both screenshot image and raw data) as evidence in the comments below. Video very much appreciated but not required.

Deadline Wed, March 14th, 12:00 midnight PST.

Gentlemen, start your engines!
Read more…
3D Robotics

[RESCHEDULED FOR TONIGHT] DIY Drones live chat/podcast with AR.Drone inventor Henri Seydoux, Tuesday night at 9:00pm PST

Posted by Chris Anderson on January 19, 2010 at 3:00pm
Free video streaming by Ustream [UPDATE #2: Okay, we're back on. This is going to happen tonight (Tues). Thanks again for your patience on this one!] On Sunday Monday Tuesday night we'll do podcast #14, 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 11:00 6:00 9:00 PM PST and will probably go about 40 minutes. This week we'll by joined by Henri Seydoux, CEO of Parrot, the creator of the awesome AR.Drone semi-autonomous quadcopter. Apologies for the late hour of the podcast this week, but it's to accommodate the fact that he'll be calling in from Paris. This one is worth staying up for! As always you can subscribe to the podcast here. Tonight's livecast will be recorded and available as a podcast on Monday.
Read more…

Webbie Test Flight

Posted by Mike Bakula on January 18, 2010 at 6:00pm
The Project SOAR group at Embry-Riddle got into the air again today. Although we couldn't get any time on the Autopilot (some problem with reading the Ublox5 GPS) we were able to test the Webbie as an on-board camera. The camera was attached to the EasyStar with 2" Velcro, which works well;

We mounted it screen-down, so the video would be upside-down. This is easily fixed in IMovie.

And here's the result!

Read more…

Another UAV-specific Job Posting - Systems Engineer

Posted by Paul Marsh on January 18, 2010 at 6:34am
In my own job search, I came across the following post which might be of interest to some here. BTW, I realize that anyone in the job market themselves would most likely find these posts on their own. On the other hand, anyone not proactively looking might see something that would interest them. Still, if the moderators would prefer I not post these when I come across them, just let me know. Thanks.Systems Engineer - UAV Operator/Operations
Read more…

Borjet MAJA CAD Model

Posted by Sentinel on January 16, 2010 at 8:42am

I've spent a few months watching DIY Drones and trying to absorb as much information as possible. It's a fantastic grass roots resource which invites one to participate in both the craft of sUAV building as well as the website.While planning out a future project, I generated a CAD model of the Borjet Maja airframe. The measurements may not be exact all over as not many details or schematics are available, however I know that the important bit - the cargo space - is exact.Anyway, I thought I'd post it here just in case it is of use to anyone else considering using the Maja as their platform. Feel free to bend/break/improve the work. If anyone wants alternative formats, just give me a shout and I'll try to sort it. (Click images to download).Cheers all,Rich.
Read more…

U.S. Diverts Spy Drone from Afghanistan to Haiti

Posted by Simon Wood on January 15, 2010 at 1:00pm
Obviously there is a lot of focus on trying to help out following the Haiti earthquake.Drones are showing their usefulness:http://www.wired.com/dangerroom/2010/01/pentagon-shares-earthquake-images-from-high-flying-spy-drone/Also OpenStreetMap are doing a lot of map tracing from donated aerial photography and making these maps for aid workers on the ground. You too can help by tracing/marking features....http://wiki.openstreetmap.org/wiki/WikiProject_Haitihttp://wiki.openstreetmap.org/wiki/WikiProject_Haiti/Press_infoSimon(aka. Mungewell)
Read more…

MARCY-1 LIFTS OFF

Posted by Jack Crossfire on January 15, 2010 at 10:30am

There it is. Marcy-1's first free flight on the golf course.The 900Mhz RC transmitter interferes with the telemetry receiver even though they're on opposite ends of 915Mhz. You need to keep them separated or on different bands, which requires rebuilding the entire transmitter.The notoriously fickle capture compare on the PIC is still extremely hard to get working in the field.

Salute the Mar.

By now, we realized she had a serious roll oscillation which is probably from not having enough weight on the balace beam.

Longest flight.

Last flight, ending in a tree impact.

Marcy-1, warrior copter.THE 900MHZ NIGHTMARE

Tracked down the SI4421 problem to a floating solder joint. The SI4421is electrically identical to the MRF49XA.

Dual 900Mhz receivers for Vika 1 & Marcy 1.

Ancient 72Mhz converter from 3 years ago.

900Mhz converter fits inside the case.

Much better.

900Mhz converter has resistors for all the inputs to prevent overloading.The 900Mhz conversion runs at 9600bps. Manual control now has the full60Hz of the RC transmitter. It was reduced to 50Hz when it was 72Mhz.

After being plagued by broken wires & floating solder joints, the Marcy1 ground station was finally capable of flight.

Vika 1 is also beginning a long hard 900Mhz upgrade. Since the MRF49XAhas only a 16 bit buffer being consumed at 86000bps, getting VikaCopter to output data fast enough requires buffering an entire packet on the flight computer & sending it in 1 shot instead of sending data as it's collected.MICROMAG3 RIDES AGAINSince we didn't win the free $parkfun hibache knife set & no-one knowsif Marcy-1 will work, that leaves digging the old Micromag3 out of thegadget graveyard & fabricating a new Marcy-1 flight computerspecifically for it.A 3rd revision will be necessary. Depending on traffic, these boardscan be fabricated in 1 commute & since we're tax paying renters, thechips are fully recycled.

Spent $30 to find out only Mane Clog Remover, only at Walmart works.Other drain cleaners have additives which prevent the NaOH fromdissolving photoresist. Mind you, you're supposed to use batchpcb.

Etching skills are a bit rusty after the draino experiments.

Size comparison. Went back to single sided boards because they'relighter with our methods.

This one has a simple dipole with choke inductors, no decouplingcapacitors, 1 digital line under the chip & it still works. Filling aground patch & using 3 decoupling capacitors is only necessary formaximum range.

Suspect any inductors above 8nH would do the job but these were whatthe balun had.

Marcy 1 phase 2 with magnetometer grafted on.

& this is the raw & derivative of the magnetometer output at flight RPM. Flight RPM has 144 samples per period. The limiting factor is radio bandwidth, not the magnetometer. It takes 20000bps of radio bandwidth to downlink that. Monocopters take the zero crossings of the derivative to get azimuth & angular rate, but it's not so easy in realtime.
Read more…