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A near tragic ArduPilot story, saved by Xbee (and GPS)!

Posted by Chris Anderson on April 8, 2009 at 10:30pm

Jordi's been doing lots of test flights of ArduPilot 2.1 and 2.2 in preparation for the Sparkfun autonomous vehicle contest. These new versions of ArduPilot include throttle control to help it handle wind better. Today seemed like a good day to test that. Jordi describes what happened: "Today i went to test my ArduPilor and winds were about 15mph with gusts of 25mph, EasyStar was having a difficult flight due to the high winds, and suddenly the EasyStar climb for about 200 meters and start drifting away from launch pad (maybe at that altitude the currents were a lot more stronger).... It was cloudy and I lost it in the sky and i was looking on the ground station how ArduPilot was trying to fighting against the wind, but the motor was almost off because the autopilot was trying to go down, but unable to travel forward, was going left and right, against the wind.... I tried to spot it on the sky over and over again to retake control, also looking into the ground station to know the direction but nothing! at that moment it was around 400 meters high!

In a matter of seconds the last position i got was 2500 meters away!! at 50 meters altitude, then i lost signal!! So i quickly took the coordinates and i made the calculation of the crash site (you know, with the last altitude and the heading i can estimate more or less the crash area, the battery was drained so no thrust at all). I've put the coordinates in motionX (iPhone app) and i begun the searching deep into the mountains!

The easystar was suposed to be lost, forever!!! And i was impressed with the range of the modem, normally i lost signal at 500 meters! Then when i spotted i could't believe it!!

And OMG i still don't know how i find it, that was horrible, hills and canyon... That was for sure luck...

Jordi"

T3

Some Tracks and Video

Posted by Rory Paul on April 7, 2009 at 7:30pm

Flight 070409, Duration 15 minutes, winds gusting South to NorthBelow is a track in Google Earth of a recent flight....doing some modification testing on the airframe and some tweaking of the autopilot. Flight was "slightly" above AMA guidelines but as I had the field to myself for the afternoon I took the liberty.

Here is a video of the flight. The footage is boring so I sped it up.(about 45mb)...BigBird_At_CIC.wmvHere is a montage of the field. Due to gusting winds it does not match up well. I am waiting for a calm morning to take some good shots.

RC tips: how to use flaperon with FMA Co-Pilot CPD4

Posted by Roberto on April 7, 2009 at 3:39am

When you use FMA Co-Pilot CPD4 on a plane with 2 servos on wing (one for airelon) usually you must connect an Y cable to use correctly CPD4 stabilization.With this configuration you cant use the flaperon mix (it move the 2 wing servo to the same direction to simulate flap).My idea is to use a V-Tail hardware mixer (it cost under 10$) to use flaperons.This is the connection schema:

The V-Tail mixer output will be connected to servos, the ELEVATOR input is our flap, i suggest to connect to gear channel, the RUDDER input is the airelon input, you must connect to airelon output of CPD4.Check on the trasmitter that on gear switch off all 2 airelon are on neutral posizition, then set the position on the gear switch on.I hope that my explanation is clear.

has anyone used this rcats ??

Posted by TESTPILOT on April 7, 2009 at 1:00am

http://www.rcatsystems.com/telemetry/telemetry_uav.phpFeatures:SENSORS- Airspeed (IAS) 10-290mph- Altitude (~8ft resolution)- RPM (200 - 40,000 RPM)- Temperature (2 measurements)- Ambient temperature- Voltage measurement (0-30V)OPTIONAL SENSORS- Accelerometer- Current- Secondary voltage- Remote ambient temperature- Fuel level- GPSSOFTWARE- Live display- Data recording (via laptop) orGPS datalogger- Data Playback- Selectable VNE & Stall alarms- Rate of Climb

3D Robotics

UAVs launching UAVs

Posted by Chris Anderson on April 6, 2009 at 5:55pm

From the description: "MADS (Miniature Aircraft Deployment System) is an Aerospace Engineering senior design project at the University of Colorado at Boulder. The mission of MADS is to deploy flight-capable, autonomous, miniature aircraft (the SuperFly) from a larger unmanned aerial vehicle (the Sig Rascal 110). Visit http://recuv.colorado.edu/MADS/ for more information!" (Actually the aircraft that are launched aren't really UAVs, since they're not guided or even controlled. And it's not clear why this team took eight months to figure out how to drop something from a plane. But it's a cool concept at least...)

3D Robotics

PicoPilot stripdown

Posted by Chris Anderson on April 5, 2009 at 1:30pm

After stripping down AttoPilot, I thought it would be fun to compare it with the last-gen consumer autopilot, the PicoPilot NAT. There's quite a difference! The most obvious contrast is how simple and basic the PicoPilot board is. It doesn't have any of the dataline protection and noise reduction features of AttoPilot, and the PCB layout itself is hobby-grade (no effort to extend the ground planes to fill all available space, which is the trick good designers use to cut down on RF noise). No wonder it tends to need servo signal amplifiers. There's also no provision for expansion (spare pins broken out, etc). U-Nav ground off all the identifying numbers on the microprocessor and support ICs, but I've identified what I could in these photographs. (click on the pictures of the board tops to go to Flickr, where you can mouse over and see what parts I could identify) There are two boards + a GPS module. One board is the wing-leveler and GPS navigation (PicoPilot NA); the other is the altitude hold board with a pressure sensor (ALT3E). The GPS module is a stand-alone component (A Holux GR-213 module with a SiRFIII chipset). PicoPilot NA top:

PicoPilot NA bottom:

ALT3E top:

ALT3E bottom:

GPS module outside (this is just a standard Holux GPS module):

The Holux GPS module inside:

To give you an idea how basic these PCBs are, here's the PicoPilot bottom and the AttoPilot and ArduPilot bottoms side by side, ranked in increasing sophistication. Again, note the careful effort to maximize the ground planes (big light green areas) for noise reduction in ArduPilot and AttoPilot, and the minimal use in PicoPilot. PicoPilot PCB bottom:

ArduPilot PCB bottom:

AttoPilot PCB bottom:

Picking a first aircraft

Posted by Tom Yochum on April 5, 2009 at 9:53am

We are looking for a first airplane to buy and we could use some advice from all you experts out there.First of all, we need something inexpensive and sturdy because we will be learning to fly RC aircraft. Secondly, we are limiting ourselves to electric for the simplicity. We would also like something with ailerons so we can use roll steering once we start programming the autopilot.We have a few ideas, but we are open to other suggestions:

GWS Estarter Park Flyer EP ARF w/EPS300C

Multiplex Easy Star

Hobbico SuperStar EP ARF w/AileronsPlease let us know what you think!Tom

3D Robotics

AttoPilot review, Part 2: The software

Posted by Chris Anderson on April 4, 2009 at 9:30pm

AttoPilot comes with two desktop programs, a full-featured ground station and a basic KML-to-TXT converter. Before I get into the specifics, I'll give some quick impressions. The Ground Station is intended to be used while the aircraft is in the air or to replay a saved flight file. It can display real-time telemetry data if you have a radio modem hooked up to AttoPilot, and can send commands back to AttoPilot if that radio modem is 2-way. It's a nicely done professional piece of software and seems to cover all the bases. Two thumbs up. The KML-to-TXT converter is a bit of a kludge, compensating for the fact that AttoPilot doesn't have a native way to input waypoints. Instead, it recommends using Google Earth ~~Plus~~ to point-and-click waypoints, exporting them as a KML file that the supplied utility can covert into a form that AttoPilot can use. Unfortunately, this process, which is pretty cumbersome at the best of times, is now also impossible, since Google has stopped selling Google Earth Plus. I've asked Dean for advice on what people should do about that, but haven't heard back yet. [UPDATE: Dean says that the free Google Earth 5 now includes the KML export feature. So ignore the Google Earth Plus reference in AttoPilot instructions, which I assume will soon be updated] There is also, to my mind, a missing piece of software, which is a setup utility. In the absence of that, the main way you adjust AttoPilot for your plane is by editing a text file that is stored on the on-board SD card. That file is pretty scary looking (and we should know, since we currently make people do something similar with ArduPilot, although we'll be releasing a setup utility that avoids that soon), and consists of hundreds of lines that look like this:

I assume that in later versions of AttoPilot, there will be some program that helps you enter those values. In the meantime, however, it's a relatively daunting process of trial-and-error, reading the manual and tweaking a supplied generic file. I haven't flown a plane with it yet, so I don't know how well the generic file will work for my target platform, an EasyGliderPro, but I'll update this as I learn more. For the rest of the review,. I'm going to focus mostly on the Ground Station software, which is the most polished part of the package. Here's the main screen, showing the playback of a flight:

The menu items give you the following dialog boxes. Settings:

When you click "Read from AttoPilot", the following boxes are added to the interface:

If you have a 2-way radio modem, those boxes allow you to send in-flight commands to AttoPilot. These are the available commands:

If you click on "Show PID", you get a new window that creates graphs of key values over time:

The "KML Utilities" launch the aforementioned KML-to-TXT file converter. You can convert both ways:

All in all, an impressive piece of software. My hope is that in the next version of AttoPilot, the waypoint entry and setup process will display an equal level of polish.

3D Robotics

ArduPilot out of stock (and moving to the Atmega328 chip)

Posted by Chris Anderson on April 4, 2009 at 4:00pm

If you follow the Ardunio world, you will have seen that the standard platform is now based on the Atmega328 chip, not the Atmega168 chip that we were all using last year. The main difference between the 328 and the 168 is that the 328 has twice as much flash and EEPROM memory. Atmel was only able to provide through-hole versions of the 328 until this month, so the only Arduino boards at the moment that use the 328 are the big development boards with DIP chips, such as the Duemilanove. But now the surface-mount version of the 328 is starting to trickle out, and it's time for the Ardunio boards to make the move to 328, too, to get access to that additional memory, which will allow us to do a lot more with the code. You'll notice that ArduPilot is now ~~out of stoc~~k at SparkFun again. That means two things. First, we've sold nearly 500 ArduPilots! Second, we let it go out of stock so as to not make any more Atmega168 boards, assuming that it's better to not sell any ArduPilots for the next two weeks than to make another batch of boards that will be immediately outmoded. [UPDATE: We're now back in stock and all board will use the 328 chip from now on.] The latest info we have from Sparkfun is that the 328 chips will be coming in this week, and we should be among the first boards to get them. We'll need to test one board, and then we can start a full production run of 500 328-based ArduPilots. If you backorder the board, we guarantee that it will be filled with the new 328 version and you'll be the first to get them. So what does that mean for current ArduPilot owners? As mentioned in the ArduPilot roadmap, version 2.2 will require the new boards with the 328 chip. But all versions before that will continue to be supported and will work fine with the current board. So if you're happy with anything from ArduPilot 1.0 to the forthcoming ArduPilot 2.1, you're fine with the current board. But if you want the features in ArduPilot 2.2 and above, you'll want to upgrade to the new board. The price will remain the same ($24.95), so this won't cost you a lot. Hardware upgrades don't come much cheaper than that!

new book: RCadvisor's Model Airplane Design Made Easy

Posted by Carlos Reyes on April 4, 2009 at 9:12am

Build and fly your very own model airplane design. Using clear explanations, you will learn important design trade-offs and how to choose among them. The latest research and techniques are discussed using easy to understand language.You will discover:* The special challenges faced by the smaller models and how to overcome them.* How to choose the right material for each part of the airplane.* Easy rules for selecting the right power system, gas or electric.* When it makes sense to use one of the innovative KFm airfoils.* Pros and cons of canard and multi-wing configurations.* A step-by-step design process that includes goal setting and flight testing.* In-depth discussions of important topics like airfoils and wing design.* The sources of air drag and how to minimize their impact.Not just for beginners! Exhaustively researched, there is something for everyone among the wealth of information it contains.Not just for electric models! The power systems chapter covers gas engines and electric motors. Most of the book applies equally well to gliders.A perfect complement to RCadvisor's online model airplane calculator, this book stands completely on its own. All of the formulas included can be easily used with a hand-held calculator.RCadvisor's easy to use calculator is the leading online tool for model airplane building and design. Numerous ToolTips, interactive tutorials, and real-time graphs make understanding easy.Carlos Reyes founded www.rcadvisor.com in 2007. He's had a life-long love affair with aviation, building and flying model airplanes since childhood. He holds a Private Pilot-Glider license and is the Vice President of his local model airplane club.

GPS & CoPilot sensor snap on turret

Posted by Reto on April 4, 2009 at 8:30am

This is the way I mount my GPS and CoPilot sensor units onto my high wing Kadet Senior.It is a simple turret made of balsa scraps in which the GPS (Locosys LS20031) lies on top and the CoPilot lies below.The GPS board is plugged into the turret with a 4 pin header since it needs independent Vcc (3.3volt unit).A four wire cable (scavenged from an old PC) with female header plug was added to the CoPilot to get rid of the built in connector. The CoPilot sensor is plugged on the side of the turret.Finally, four magnets will be epoxied at the base of the turret and 2 x 4 pins female headers will be epoxied through the top surface of each wing half. So the turret can be snapped/plugged steadily onto the wing and taken off after flight to be carried with other valuable devices in a separate case.Here some pics of the modifications

FMA CoPilot thermopile sensor

Soldering breakout cable to dismantled FMA CoPilot

CoPilot with breakout cable

Locosys LS20031 GPS board with 4 pin male header

Plugging GPS board into turret

Adding some foam pad between GPS and CoPilot

Plugging CoPilot and inserting into turret

Turret back view with inserted devices

Turret side view

Moderator

Airframe testing

Posted by Gary Mortimer on April 4, 2009 at 6:49am

Before commiting expensive gear to an anything and in the interests of I wonder.

I have been flying this airframe quite hard.Yesterday I load tested it using five of these

at 58g each the multipack 5 came to 290gWithout load I have achived flights in the order of one hour obviously that will change.The aircraft has a 40 inch wingspan and easily fits on the back seat of my car. A simple solution for when we go out and get this sort of shot

Working towards an Attopilot being fitted for vertical stitch shots of archaeological stuff.On the drawing board a more efficient wing and larger, probably just shy of 2m easily able to lift 500g for one hour.A platform nose for FPV/Stills cameras and plenty of internal space for vertical/horizontally mounted cameras and gear.Flat wing this time with outboard ailerons. The airframe being roughly double this ones size. Also thinking of having a small or large wing for different tasks or wind speeds.Hopefully some pictures of a rough setup within the month.This bigger airframe will be used for some animal research tasks in Kenya, Tanzania and South Africa. Mostly lifting repeaters for animal tracking collars.For test Airframe 1, I have set up a TwitPerhaps the first UAV airframe with its own Twitter feed??I am hoping to fly 100 hours in the next month or two, so far I am ahead of schedule but weather is coming next week so I'm sure that will get in the way.

3D Robotics

ArduPilot Roadmap

Posted by Chris Anderson on April 3, 2009 at 11:30pm

As you'll see, we're releasing versions of ArduPilot at quite a clip. The difference between them can be a bit confusing, so here's a roadmap:

1.0: Just navigation and altitude hold (released 1/09)
2.0: Adds XY-sensor stabalization, EM406 only (released 3/09)
2.0.1: Adds Z sensor, ground station support (released 4/09)
2.1: Supports XY sensor in diagonal position, desktop setup utility (does not require Arduino IDE), throttle (if airspeed sensor/shield is connected). Due week of April 20th
2.2: Requires ArduPilot 328 board (current board upgraded to the Atmega328 chip; stay tuned for details). Supports any GPS, fully configurable for different airframes, new navigation modes. Due early May
Shields: We will be releasing expansion boards (called "shields" in the Arduino world) that plug into the top of ArduPilot and add additional features and connectors. This first one just adds a differential pressure (airspeed) sensor, 3.3v power regulator, lots of handy ways to add other sensors and GPS modules, and a circuit that allows you to upload code without unplugging the GPS. The first board will be available in May.
3.0: ??? Additional sensors (speed, power). Maybe IMU support?
ArduPilot Pro: new board based on Arduino Mega. IMU based. Winter 09

Developer

Ardupilot 2.0.1 Released

Posted by Jordi Muñoz on April 3, 2009 at 10:00pm

Main changes:-Solved compatibility issue with Arduino IDE 14 and 15, (thanks very much Arduino Mega).-Z Sensor support (extremely recommended, otherwise you will fly strange).-An small Ground Station based in Labview to play with ;-)...And can be donwloaded from here.The problem with the Ground Station is that i can't compile it, but you can run it if you have Labview installed. Later i will release the EXE.It includes a better virtual horizon and displays Speed, Altitude, Climb rate, Heading, Bearing and show the aircraft position in real time using Google Earth.What you need:-Any radio modem (XBEE) running at 57600bps.-Labview 8.6 installed.-Run the file "groundtest.vi".-Select the port number, then click open and enjoy!(You can try it with the FTDI cable if you don't have radio modem).Note: This ground station is same I'm using right now to debug the new ArduPilot firmware 2.1.Ground Station download click here.[UPDATE: The Ground Station for Labview 8.5 please Click here]Be ready for the next release of ArduPilot firmware, the version 2.1, that will include:-Diagonal X Sensors.-Throttle Control-AirSpeed Sensor Support[Warning: You need Arduino 0015 or higher in order to use this firmware]

Autopilot test successful

Posted by Lorentz on April 3, 2009 at 2:02pm

At last it worked ! Here's a short video, not high quality indeed. Hope it is intelligible.Autopilot_Test_Air_LD.wmvHere's some pictures of the airframe.

Front

Back

Closeup of camera, thermopile stabilizer, GPS, video transmitter, ground plane antenna.

"da braain"

brain's right emisphere

brain's left emisphere

3D Robotics

AttoPilot review, Part 1: The PCB board

Posted by Chris Anderson on April 2, 2009 at 11:39pm

I just got an AttoPilot in and plan to review it in several parts. Today's part: the PCB board. As you might expect from a former Intel engineer, Dean Goedde has done a great job of PCB design. Neat trace layouts, good noise protection and robust components. The board is based on a 5Mhx Parallax Propeller chip, with 8 cores. It has a differential pressure sensor for speed and a single pressure sensor for altitude. It also has 512k of on-board memory in addition to that in the Propeller chip. Click on the photo and you'll be taken to Flickr, where you can mouse over the components to find out what they are

And here's the bottom of the board. Click on this one, too, to find out what the components are:

A New and Interesting Microcontroller

Posted by Matt Fisher on April 2, 2009 at 11:30am

I think I may have to get one of these. It can run a 32bit OS off microSD, 1000MHz CPU with 256MB DRAM and do it all off of 2 watts!Is anyone as keen about getting there hands on this as I am!? A Linux distro for UAV's anyone?Article on Make Blog

In the beginning...

Posted by Tom Yochum on April 2, 2009 at 8:36am

My name is Tom Yochum and my neighbor (Brian Hudson) and I are starting a project to create our own UAV from an RC aircraft. This blog will be used to help document our trials and tribulations.About us.Brian is a Microsoft guy, which makes him really smart. He has a computer engineering degree from USC, and he knows everything we will need to know about embedded computing, board design, and coding. Well, at least I think he knows everything.I graduated with an aeronautical engineering degree from the University of Washington with an emphasis on control system design. I now work for the avionics manufacturer Universal Avionics as a system engineer. I primarily work on navigation and guidance for the Universal Flight Management System (FMS). I have experience with aircraft modeling and simulation, aircraft navigation, Kalman filter development, and control law development.Between the two of us we think we have all the tools we need to convert an RC aircraft into a fully-autonomous UAV. We are still determining the full scope of our project, but we have some ideas about our final product. These include:Autonomous takeoffs and landingsPre-programmed aerobatic manouvers (loops, rolls, tailstands, etc.)Payload capability (a camera, perhaps?)Bi-directional datalink to a ground stationAs a first step, we are likely going to follow in the footsteps of the efforts outlined here in this excellent website. We are making plans to purchase aircraft and processors now. Our first aircraft will do basic waypoint navigation only. More advanced features will be added incrementally.We look forward to sharing our triumphs and failures with all of you.Tom

New Sparkfun Toys - Atomic IMU 6 DoF

Posted by Simon Kerr on April 1, 2009 at 4:00pm

New IMU offered by Sparkfun here. I think this board has some great potential that could lead to some all singing, all dancing Arduino-native IMU.The fact that this IMU is built around the ATMege 168 makes me think that it could be re-flashed to become some sort of "ArduIMU" board, and even run a ported version of the "Premerlani-Bizard robust direction cosine matrix estimator / MatrixNav firmware" as per this suggestion.Perhaps this board could be partnered with the ArduPilot, the IMU doing its thing, and the ArduPilot providing GPS info and servo driving?Anyone got any opinions for or against this? Or even better, technical reasons why this a) won't work, or b) is an awesome idea! :DSimon

Developer

Arduino Mega Now Available!

Posted by Jordi Muñoz on April 1, 2009 at 9:19am

Good news! You can now buy the new Arduino platform here.For more information about it visit the official website here.

Blogs

All Posts (14054)

A near tragic ArduPilot story, saved by Xbee (and GPS)!

Some Tracks and Video

RC tips: how to use flaperon with FMA Co-Pilot CPD4

has anyone used this rcats ??

UAVs launching UAVs

PicoPilot stripdown

Picking a first aircraft

AttoPilot review, Part 2: The software

ArduPilot out of stock (and moving to the Atmega328 chip)

new book: RCadvisor's Model Airplane Design Made Easy

GPS & CoPilot sensor snap on turret

Airframe testing

ArduPilot Roadmap

Ardupilot 2.0.1 Released

Autopilot test successful

AttoPilot review, Part 1: The PCB board

A New and Interesting Microcontroller

In the beginning...

New Sparkfun Toys - Atomic IMU 6 DoF

Arduino Mega Now Available!

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