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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
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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.
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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 stock 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!
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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.
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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

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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 shotWorking 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.
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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
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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]
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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
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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 AttoPilot board top And here's the bottom of the board. Click on this one, too, to find out what the components are: AttoPilot board bottom
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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
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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
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Recent MAV work with AttoPilot

Posted by Dean on March 31, 2009 at 10:58pm

Check out my thread on RCGroups for a recent 8 ounce flying weight plank MAV: http://www.rcgroups.com/forums/showpost.php?p=11923347&postcount=2445Specs:Flying mass: 225 grams (8.0 ounces)Motor: GWS model GWBLM001A for 2s LipoProp: GWS 6050Battery: Common Sense RC 700mA 2sESC: Castle Creations 15 ampServos: 2 HS-55Rx: Berg Stamp 4 with header pins removedControls: Elevon and throttleSpan: 18"Chord: 8"Airfoil: Eppler 186 (very reflexed)Center where motor is: Eppler 186 but 180% thick on top, 140% bottomRx/Autopilot and Battery bays: E186 140% top thick top and bottom.This is a plank flying wing. To get the C.G. forward enough, all gear has to be almost against the wing LE. This means the motor cannot be in the back, however I still wanted this to be a pusher. The solution: motor in the nose with a 3mm carbon rod shaft and ball bearings, 6" long.AttoPilot: This is without case and no header pins. The servos and all sensors are directly soldered to the PCB. The SD card socket is attached to the Atto with right angle headers. The pitot is a 1/8" OD brass tube sticking out only 6mm from the LE. The R/C Rx (Berg Stamp4) is around 2 grams without headers, and this is situated directly on top of AttoPilot. Autopilot + Rx + GPS + thermopile sensors + power sensor is 48 grams (1.69 ounces).The voltage/current sensor is also custom in that it has only 1 shunt resistor. This doubles the resolution (11 mA) and reduces the current range to 45 amps.There is no payload, camera, or modem on this now... however in a 8 ounce MAV package I think it significant to have these standard AttoPilot features:1) practically unlimited onboard data logging of 70 parameters at 5Hz2) Airspeed control (not simply hold)3) Power sensing and mAh abort triggers4) barometric altitude5) FULL SIZE gps (greater sensitivity and lock solidity than the really small GPS)6) all the other stuff (50 Hz attitude, exponential gains, line hold navigation, no pre-flight calibration of anything).I'll be using this to hone the automated landing code that is underway, and perhaps rework the autonomous take off to better suit planes with pusher prop (detection of hand toss then small delay before motor comes on).
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3D Robotics

Preparing ArduPilot for version 2.1 (with Z sensor)

Posted by Chris Anderson on March 31, 2009 at 10:30pm

Here's how to connect the FMA XY and Z sensors. [Note: the sensors come from FMA with a thin film (usually red) over the thermopile lenses. You have to remove the film before using them.] The basic connections are as shown in this picture:

Cut one of the cables that comes with the FMA XY sensor in half and pull the four wires apart for about two inches. Strip their ends by about a quarter of an inch. Do the same for the Z sensor (you can cut off the fourth wire, the one furthest from the red one, off at the sensor level since it isn't used on that sensor). Twist the red wires and the one next to it from each sensor together, since they'll be sharing a connector. Now it's time to slip on heat shrink tubing. If you have some red tubing, put it on the two twisted-together second wires in from the sides of the cables with the red strip, to mark the positive power cable (yes, that's confusing. V+ isn't the wire with the red strip--it's the wire next to it!). Black tubing goes on the two twisted-together red cables (which are Ground, which is confusingly the red one). Slip tubing on the other three wires, two from the XY and one from the Z senors. At this point the instructions depend on whether you're powering the board from the Rx/ESC, as most people are, or if you're powering the board via the BATT pins. The following is for the standard boards using Rx/ESC power. Notes for BATT power are below in [brackets]. Solder each wire or pair of wires on a five-pin male machine pin header like the below (use the picture above to get the order right, and solder the two ground and V+ wires together at each of those two pins). If you haven't already done so, also solder a five pin female machine pin header in the five holes made by ArduPilot's Batt -,+ and Analog 0,1,2 holes. By combining all the sensor wires in one strip, we can ensure that we'll have the best, strongest connection:

How did we get that otherwise unused Batt + pin on ArduPilot to actually be +5v? By soldering a wire on the bottom from the VCC pin in the FTDI row!

[If you are powering the board from the BATT pins, you'll need to attach the sensors differently. Solder a three-hole female header in the Analog 0,1 and 2 holes, and a two-hole header in the VCC and GND holes in the FTDI row. Solder the three sensor data lines to a three-pin male header in the same order as above, and combine the V+ and GND power lines from the two sensors to a two-pin male header. Connect the matching male and female headers.] Note that for the 2.1 version of the software, the sensor should be placed diagonally on the aircraft so the cable plug is facing backwards (towards the tail) and the FMA logo is at the front, as shown in the picture at the top. If you want the cable facing forwards, you can change that in the code. (look for "#define REVERSE_X_SENSOR 1 //1 = cable behind, 0 = cable front" in the first tab) Here's a diagram that shows how everything hooks up:

Here's a very simple program that will test all your sensor (XY and Z). Just load it on ArduPilot (make sure the board is powered and the GPS is not connected). With the FTDI cable connected, click on the serial monitor icon in Arduino and make sure the speed is set for 9600. The program will prompt you to tilt the sensor in certain directions and then strike any key and hit return when you're ready to take the X and Y sensor readings. Remember that sensor readings inside and near heat sources (like your hand) are nothing like the real thing outside. But it's still a good way to confirm that your sensor is working right.
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Dreaming of wings

Posted by Brian Hudson on March 31, 2009 at 10:24pm
My name is Brian Hudson. I've been wandering around DIY for a week or two now, and I've decided to start this blog to start interacting with the community, get feedback, and to track progress and thoughts on a project my neighbor and I are starting.My background is in Computer Engineering and Computer Science and I've worked in the software industry for several years now. My neighbor has a degree in Aeronautical Engineering, and we’ve been talking for awhile about a UAV project.In middle school and high school, I built a lot of models, eventually building my first R/C, the Sig Riser 100. This wasn’t an easy plane to start flying with around our large property, so I worked on a couple other models over time. My first flight at a true R/C field was a .40 trainer, although I wasn’t with a real instructor, and my first attempt at a landing ended with a nose dive of epic proportions :PBudget and time kept me from pursuing flight much further once I started college, but I always had a desire to get back to both model building and to get experience with R/C flying. I’ve always enjoyed watching aerobatic maneuvers, but never knew whether or not this would be something I could aspire to.As part of my Computer Engineering / CS degree, I had a design project requirement. A lot of other friends I had did things varying from simple lawn sprinkler controls to more complex client server software systems or mesh networked robots. I was fortunate enough to have a working relationship with a research lab where I was given a project to build a microcontroller based input / output multiplexing interface between an R/C car and an on-board 2 node Beowulf configuration of single board computers. The lab’s main area of research was computer vision and its applications toward studying human vision and neurology. Hence, the car had lots of sensors including web-cams, and the goal of my project was to make the use of this robot to test out algorithms and theories less painful – as you can imagine, grad students working on vision research were able to concoct plenty of algorithms and control schemes that flung this robot all over the place and crashed the onboard computers plenty of times. My project had several interesting features:- Ability to dynamically switch R/C control of the car between the on-board computing cluster and the received signal from the R/C transmitter. This also included the ability to pass “training” data to the computer, so that the computer could attempt navigation based on its video input, and could “learn” from corrections passed in by an observer.- GPS data input. This was another data point that could be read into the system and used for navigation and historical mapping etc.- On-board LCD menu and button interface. Basically, I had a small and simple library that allowed configuration of 5 on-board switches and which displayed a menu on a 4x20 LCD screen. This allowed for simple booting out in the field, with enough flexibility to run several different scenarios and simulations and store data to the onboard disks without having to drag along a keyboard and monitor. Now-days, the ubiquity of wireless networking probably makes this a little outdated, but it was handy back then - A serial protocol which allowed the controlling PC to configure the various peripherals like the buttons and LCD, read and write servo data, read GPS data and restart and recalibrate the various components in case the on board computer crashed in the field.I had a blast building this system, and it was really gratifying to start with a couple PIC microcontrollers in a tube, a few components, some flashing software and an idea and come out with a PCB design and some cool firmware to make this robot more fun to work with. I learned a ton through the whole process, and that’s part of the motivation for this project, to learn more about aviation, and get my hands dirty plugging some parts together.I think at this point autonomous flight is a pretty high goal, as I haven’t really (successfully) flown a plane myself and neither has my neighbor. But I’m certain we’ll have fun going through this process – probably have times of faster development and times of slower development, but overall we should have some fun.Ok – so let’s start with some operating parameters:1) Cost. We’re trying to stick within a fairly modest budget. I don’t think we have an explicit dollar amount limit, but at least from my end, I’m going to be working within my normal family monthly budget, which means I’ll probably be buying a few things each month to bring the project farther along (starting with the dev board and maybe the accelerometers or gyro, later adding GPS module, probably a couple of XBee’s for bi-di telemetry).2) Space. This one might sound a bit weird, but I live in a Condo, and my darling wife and baby don’t want me taking over a whole room with this hobby, so I won’t have space like when I was younger and building full kit R/C planes. We’ll need to start with some sort of ARF.3) Tools. Similar to space, I don’t really want to get in over my head as an electronics hobbyist here – I’m not afraid of soldering (although with a baby, I’m terrified of lead solder  ), but I don’t want to have to set up a whole mini-electronics lab to get this project going. This is a big motivator for my microcontroller platform selection. Currently, I’m trying to decide between an Arduino Duemilanove or the ArduPilot. Duemilanove seems a little more flexible with the shield options and on board USB connector for programming, debugging etc. Yet, I like the fact that the ArduPilot has a dedicated on-board fail-safe microcontroller for R/C control muxing. I’ll have to look back at my college project to see how I handled input muxing there, because I’m pretty certain I had a channel on my radio that dealt with this – so I could probably re-use some of that design.4) No Glo. I’ve dealt with glo engines in the past with my models, and this was just simply too much hassle. I hope that the reduced selection of models and high initial cost of batteries, chargers etc doesn’t prove prohibitive to our budget, but I’m feeling pretty firm about this, and it seems like the rest of this community feels similarly.I’m not sure if there are any other major constraints here. I’m super excited about this, but also trying to keep from burning out by setting expectations initially too high or by getting frustrated by the fact that my time investment here will be subsequent to my day job and family life.So to conclude, I hope that hanging out on these boards will help me gain knowledge from the work of others, and to start with, I’ve got a couple of questions for others with experience here!1) Power supply – I’m looking to use an ESC with a BEC, but if I choose to use the Duemilanove, its power input requirements/recommendations have 6V as the minimum input supply. I believe the R/C standard is 5V. Now, I know that USB is 5V and the Duemilanove is designed to run from USB. Is there something I’m missing here? This is the first potential deal-breaker or the Duemilanove, and I’m really liking its potential here, so I’d love to find a “don’t worry about it” type of answer, even if it meant I might need to do some sort of power isolation for my servos (although that might generate more “help-me!” questions.2) Components – I’m looking for a simple starter set of components including wiring, a breadboard, some common LEDs, caps, resistors etc. Back in school, all of this came as part of the prototyping lab. Wow, I didn’t know how spoiled I was. I’m able to find many of these things piecemeal, and some of these things on sites like SparkFun, but especially regarding the components, it would be nice to find a simple kit, even if there’s some markup over ordering components from digi-key or something. Does anyone have a recommendation here?I’m looking forward to posting again with my next level of investigation, and I hope to hear from you all!
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Reading Saitek Pro Flight Yoke System Data for UAV Usage

Posted by Matt Fisher on March 31, 2009 at 4:00pm
Here is the (Python) code I used for getting my Saitek Pro Flight Yoke (http://www.saitek.com/uk/prod/yoke.htm) data from the device into something usable. Python has a fantasic pygame library which reads joystick data. This is just a simple script that is short and sweet. This code reads all the motion axis (ie. the yoke, hat and throttles, ) and all of the buttons. Feel free to play around with it. I really dont want to use a RC transmitter for my UAV as I can so so much more with this device. Let me know what you think.And you don't need the Pro Flight Yoke to use this - any joystick will do :)USAGE NOTE: to execute type 'python filenameyousavethecodeas.py'######################## START CODE ##############################import pygamejoy = []# Handel the joystick eventdef handleJoyEvent(e):# Check for joystick axis movementif e.type == pygame.JOYAXISMOTION:axis = "unknown"if (e.dict['axis'] >= 0):axis = 'a' + str(e.dict['axis'])if (axis != "unknown"):s = "%s|%f" % (axis, e.dict['value'])print s# Check for buttonsif e.type == pygame.JOYBUTTONDOWN:if(e.dict['button'] >= 0):print 'b' + str(e.dict['button'])# wait for joystick inputdef joystickControl():while True:e = pygame.event.wait()if (e.type == pygame.JOYAXISMOTION or e.type == pygame.JOYBUTTONDOWN):handleJoyEvent(e)# main methoddef main():# initialize pygamepygame.joystick.init()pygame.display.init()if not pygame.joystick.get_count():print "\nPlease connect a joystick and run again.\n"quit()print "\n%d joystick(s) detected." % pygame.joystick.get_count()for i in range(pygame.joystick.get_count()):myjoy = pygame.joystick.Joystick(i)myjoy.init()joy.append(myjoy)print "Joystick %d: " % (i) + joy[i].get_name()print "Depress trigger (button 0) to quit.\n"# run joystick listener loopjoystickControl()# allow use as a module or standalone scriptif __name__ == "__main__":main()
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Ground Target Tracking with Road Map Support

Posted by Matt Fisher on March 31, 2009 at 12:03pm
I found this paper titled "Ground Target Tracking with Road Map Support" written by Daniel Streller (daniel.streller@eads.com).http://subs.emis.de/LNI/Proceedings/Proceedings110/gi-proc-110-021.pdf (5 page PDF, 161KB)Its somewhat of a complicated read but very interesting as well.The UAV I am planning to build will have alot of onboard memory which I will use to store road data from a automobile GPA system. This data will be used to properly find waypoint by keyname rather then lat/long. Since my UAV is to have a good camera on it, I am very keen to dig into ground target tracking and autonomous waypoint creation and this seemed like a good start.
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