Chris Anderson's Posts (2718)

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3D Robotics

Making a UAV fail-safe

A big part of the DIY Drones credo is keeping it safe, and by that I don't just mean adhering to FAA regs and staying away from built-up areas, but also keeping it safe for your expensive UAV! The truth, as we all know, is that computers crash and that aircraft flown by computers crash harder ;-)

The aim of a good UAV is to have a fall-back system by which a human pilot can take over if (when!) the autopilot goes funky. There are at least three ways to do this, all of which we feature in one or more of the autopilots here:

  1. Completely separate the navigation and stabilization systems and ensure that the stabilization system can be overridden by manual RC control. That's what we do in GeoCrawlers 1, 2 and 3, all of which use the FMA Co-Pilot for stabalization (it controls the ailerons and elevator, leaving just the rudder for the autopilot and navigation). If the autopilot crashes, you can still fly the plane with ailerons and elevator alone, something we end up doing all too often! (The FMA system always allows for manual input)
  2. Mechanically separate the autopilot and RC control systems. In the case of the Lego UAV ("GeoCrawler1"), the Lego Mindstorm system moves the whole rudder servo back and forth, but the RC system can always turn the rudder servo arm, allowing it to override the autopilot if need be.
  3. Install a stand-alone "MUX" or servo multiplexer, that allows the operator to switch control from the RC system to the autopilot and back again with the gear switch on the transmitter, even if the autopilot catastrophically fails. As far as I know, there's only one commercially available one of these out there, and that one, by Reactive Technologies (shown), is not cheap ($99). Still, if you install one and give it an independent power supply, there should be no reason why you can't regain control of your plane no matter how wonky your onboard computer has gone.
What you should probably not do is exactly what we do (temporarily) with the Basic Stamp autopilot (GeoCrawler3), which passes RC signals through the Stamp chip and synthetically recreates them on the other side for the servos. If that program has a bug or the chip otherwise freezes, you've basically lost your rudder and elevator, which could make keeping the plane in the air difficult indeed. You'll still have control of the ailerons and throttle, but good luck getting the plane down in one piece if your program decides to crash with the rudder and elevator at full deflection.

So the Basic Stamp UAV project might be a good place for a MUX. Anybody know of a cheaper one? (This guy is looking for one, too)

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3D Robotics
A mindblowing report from Hackaday:

"The 24th annual Chaos Communications Congress in Berlin is already off to a great start. The first talk we attended was [Antoine Drouin] and [Martin Müller] presenting Paparazzi - The Free Autopilot. Paparazzi is an open source hardware and software project for building autonomous unmanned aerial vehicles. The main hardware board has an ARM processor and GPS. It uses inertial and infrared sensors to determine orientation and altitude. The four infrared thermopiles measure the air temperature. The ground is warmer than the sky and if you compare the temperature in the direction of each wing tip your can tell what angle the airplane is at. It's really that simple.

They did a pretty amazing live demo. Using the network connection they controlled a UAV flying in France and another in Germany. Both planes were streaming live video from belly mounted cameras. One relaying through a home DSL connection and the other through a UMTS cellphone. They were able to change way-points on the fly and issue flight pattern commands. There is a ground crew at each location with a security pilot that will switch the controls to manual if things get out of hand."


The slides, which are a must read, are here. The video of the presentation is here.

I'm giving a DIY Drones talk/demo at Etech in March with blimp UAVs. But it will be hard to top this.
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3D Robotics
Jordi has opened my eyes to the Arduino platform, which is being described as a "Basic Stamp killer". Is it a good candidate for autopilots? Well, let's look closer. Arduino is an open source embedded processor platform, based on the ATMega168 CPU, which has more memory than the Stamp and is a lot cheaper. There's proper development software available and SparkFun has a full line of dev boards and other accessories. Its programming language looks like C but should be easy enough to learn for people who know Basic. It started as an Italian project (it's named after an Italian king) and still has a European flavor, so that may explain why we in the US don't know it well. But Jordi, in Mexico, had done some very interesting work in exploring its potential as an autopilot platform. His main project is the "Arducopter" (shown at right), which has resulted in some very nice code, such as this navigation routine. In his comments, Jordi (BTW, he's just 21) described some of the cool things he's doing with it, which I'll simply quote with links here: "This is my first test with Boarduino (a breadboardable version of Arduino) controlling servos and using an accelerometer from a Nintendo Wii. Right now I'm using Gyros and Kalman filters. I even wrote code to read PMM signals, the GPS is finished and working pretty well, the IMU is in beta, and I'm developing an altimeter using I2C technology and high quality pressure sensors." Here are some links he provided: I'm intrigued. I don't see anything here we can't do with Basic Stamps with a little fiddling, but I have to admit that certain projects look like they would be easier with the Arduino, mostly thanks to its greater memory and full range of variable types, including floating point. Anybody else looking seriously at Arduino?
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3D Robotics

Basic Stamp autopilot tutorial, part 5

In my last tutorial, I showed you how to upgrade from the 12-sat Parallax GPS module to the much better (and cheaper) 20-sat EM406. Unfortunately, my instructions weren't compete and I've spent a frustrating week actually trying to get it to work properly. I've now diagnosed the problem and fixed it, so this tutorial will help you avoid the problems I ran into.

Just to remind you, the main difference between the Parallax GPS board and the EM406 is that the EM406 is a bare module that you've got to wire properly onto your Basic stamp dev board, and the EM406 outputs raw NEMA "sentences" that you need to parse rather than specific requested data fields as is the case of the Parallax board (trust me, the slight hassle of working with the 406 is more than made up for by its great performance).

In my instructions last time, I advised you to follow this tutorial that was in Servo Magazine this month. Unfortunately it has a serious error in the diagram of the EM406 pins--it actually has the Rx and Tx pins reversed. This took me days to work out, and eventually I went to the manufacturer's datasheet for the EM406 to get it right.

The only three wires you need are 1, 2 and 4. That's ground, V+ and Tx. (pin 5 is another ground, which I've also connected to pin 1 in the picture, but I don't think that's actually necessary).

If you click on the photo above, you can see that I've soldered those wires onto a header strip, plugged it into the Basic Stamp dev board's breadboard, and connected the Ground, V+ and Tx wires. I connected the Tx wire (the white one in the picture) to the Basic Stamp's pin 9, although you can choose any unused pin you want.

Here's the Basic Stamp code that will test the setup above. As always, change it if you're using a different pin for the GPS Tx or if you're using a Stamp other than the BS2p (by modifying the "GPSBD CON 500" as instructed by the comments on that line)

The EM406 should get a sat lock (LED starts blinking) in less than a minute, indoors or out. When you run the above code, your debug screen on your PC should start showing NEMA sentences with lat, lon, and a few other data points. You can then decide what data fields you want in your autopilot and write your code accordingly, or incorporate a full GPS parser as discussed in this series.

Previous posts in this series:

Tutorial 1 -- Servos
Tutorial 2 -- Reading the Rx
Tutorial 3 -- Adding GPS
Tutorial 4 -- Upgrading your GPS
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3D Robotics
By popular demand, I've added two pages on this site, linked to from the text box on the front page
Given the constratints of the social networking platform we're on, the way these are set up is as blog posts that can be edited at will. Ultimately, I'll allow you to edit these pages yourself, wiki-style, but for now if you'd like your project to be included, please leave a comment on the relevent page or private message me (envelope icon above) and I'll include the links. No doubt I've missed a bunch of projects. Let me know what you'd like me to add.
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3D Robotics
Like everyone else, we're huge fans of the Multiplex EasyStar, a cheap, sturdy and good-flying powered glider. It's a great aerial imaging platform (see our how-to here), but a bit small for a full suite of autopilot electronics. Fortunately, Mutiplex makes some bigger birds, too: the $195 Cularis and the $70 EasyGlider (shown).

People (such as our own Paul Gregory--see his build tips here) have tended to go straight for the larger Cularis in seach of room and lifting power for bigger cameras and more electronics, but Stewart Long from Pict'Earth, who tried that, has just written in with some cautionary advice and a surprising recommendation.

He says:

"The increased size of the Cularis has not allowed us to use larger cameras that we could with the Easy Glider. the wings are larger, and with more lift, but the Cularis that we set up was too nose heavy , even without a camera. We tried counterbalancing the setup by placing the servos in the rear of the plane, but the plane remains overly nose heavy. We have also had a difficult time with the wing spar, servo connection and latch mechanism. Because of this the plane flutters a little bit like the Easy Star.

So, the Cularis provides some interesting features, but I see a lot more bang for the buck with the Easy Glider. The materials cost is half with the Easy Glider, the flight of the wing is great, and the center of gravity in the Easy Glider allows for more tinkering. From an RC operations standpoint it was not very difficult for me to start using the Easy Glider after starting with the Easy Star.

Here is the setup for the Cularis:

  • Motor Dymond Gunther
  • ESC Hacker 70
  • Prop Cam 14X9.5
  • Lipo generic 2s3p (2 cell x3)
  • (Approx 450 watts, with 75 degree climb.)

Easy Glider (photo setup shown):


Easy Star:

  • Motor: "Multiplex Permax 480-4D , and Multiplex Permax 480-6D. The 4D is more powerful, and will fly a heavier plane. With the 4-D full throttle is too high, I take off with about 60% throttle. The disadvantage to the 4-D is that it wears down the lipo battery over time. This has not proven to be a big problem though, because we have lost batteries at a higher rate"
  • Speed Controller: "Castle Creations Thunderbird" 36 Amp
  • Propeller: 6/4 plastic. "The first number is for thrust, the second number is for speed. The higher the number, the higher the value. For our platforms we want to have more thrust than speed."
  • Lipo: 3 Cell 2100 mAh


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3D Robotics

Blimp UAV project: spec'ing it out

As discussed in the white paper, the aim of the blimp UAV project is to build a prototype for an indoor aerial robotics contest. This will require contestants to design, build and program a blimp that can navigate a course inside a gym-sized space and potentially do certain tasks such as spotting targets and landing at intermediate points.

To do this, our blimp has to be able to know its current position in six degrees of freedom: x, y, z, yaw, tilt, pitch. This is hard enough outdoors, but it's especially tricky indoors, where GPS doesn't work. So what we're planning is a blimp with the following components, including a cool IR beacon-based system (shown) to simulate GPS:

  • Blimp: BlubberBot envolope (46"), which can carry a 125 gram payload
  • Inertial sensors: two-axis accelerometers for tilt and pitch, magnetometer for yaw.
  • Position sensors: Evolution Robotics NorthStar system, which uses stationary IR beacons in the room as reference points (not unlike the way a Roomba makes its way back to its charging station)
  • Altitude (Z) sensor: untrasonic sensor with 3-meter range
  • Three motor system (differential thrust for left and right, and one for up/down), like the Plantraco Microblimp
  • CPU: Undecided, but may well be Pic-based.
  • Usual I/O, including serial/USB for programming and a servo controller for at least two micro servos (use to be decided)
  • Power: 200 mah LiPos (5.4 grams)
  • PCB: Approx. 1x1.5 inch board (1/32” thickness for weight savings)
  • Programmable in RobotC
Seems very doable within our weight limit. Next step: CPU selection and building a breadboard prototype with the NorthStar board.
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3D Robotics

Blimp UAV project: The beginning

Aside from building this site, my two big UAV projects are taking the Lego Mindstorms UAV to the next level (it's mindblowing, although I can't talk about it yet!), and building a prototype blimp UAV as a platform for a potential indoor aerial robotics contest.

This particular blog series is going to be about the development of the second of those, the creation of a sub-$1,000 fully autonomous indoor blimp UAV.

For the curious, my white paper on why we picked blimps, rather that quadcopters, helis, microlight planes, etc, is here.

Now that we've settled on blimps, we had to start by trying what was already out there. To get a feel for how blimps handle, I got the best (affordable) RC blimp: the Plantraco Microblimp, which is a lovely bit of superlight engineering, with a 2.4ghz RC system, fully proportional controls, and LiPoly rechargeable batteries (it's the silver one on our dining room ceiling at right). First lesson: blimps have HUGE latency issues. Basically the inertial momentum means that you need to anticipate all of your turns by many seconds. That means that an autopilot will not only have to know where it is in six dimensions (x,y,z yaw, tilt, pitch), but also have an internal model of the blimp's response time (which ranges from slow to slower). Fun!

The second blimp we checked out is the only autonomous blimp you can buy (without a security clearance). It's the BlubberBot featured in Make Magazine last month (it's the the big white one in the picture above). I was particularily intererested in it because it's about the size we want for our blimp (46"--a bit less than four feet--long) and I was curious about how other people handled blimp autonomy.

(BTW, those weird pink and blue things hanging off the bottom are children's forks and spoons for ballast!. I wanted to find out how much weight that envelope could carry [answer: about 125 grams] and so I filled it with more helium than recommended. That meant extra ballast, which meant raiding the kids' silverware drawer.)

It took all day to build the kit, which requires soldering all the components to the PCB and connecting four sensors (light left and right, touch at front, and, randomly, cellphone proximity) and four output components (sound, vibration and two LEDs). It uses a pre-programmed ATMega168v CPU and two motor driver chips for the two props. No vertical control.

You can see the PCB at right, with the cellphone sensor hanging off the bottom. Overall, it's missing quite a bit of what we want in a proper blimp UAV, from programmability and location awareness to proportional control. It's designed to seek out lights and bounce off walls, and I suppose under the right lighting conditions it might actually do that (mostly it just wanders about). But we need more.

One thing that I did learn from the BlubberBot, however: There's no need to keep the motors going all the time, as you might with a plane. The BlubberBot pulses the motors, then coasts while it reads its sensors, then pulses them again in 10 or 15 seconds. I think we'll do the same with ours. A great way to save power!


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3D Robotics

Basic Stamp autopilot tutorial, part 3

SparkFun has quite a few GPS modules, but I prefer the EM406, because it uses the standard 5v power we're using on the dev board (as opposed to the EM408, which needs 3.3v) and has a handy red LED to show sat acquisition status (the 408 doesn't).

There are two difference between using the Parallax GPS module and a third-party one like the EM406. The first is that you've got to wire up a connector so the EM406's cable can plug into our Basic Stamp breadboard. The second is that while the Parallax GPS module has a "smart mode", where you can query the GPS module for a specific data field (lat, lon, # sats, etc) and it will return just that, most other modules such as the EM406 continuously output all their data in "NEMA sentences" that you have to parse.

The connector you need to wire up looks like this (right), and is simply made by cutting off one end of the connector cable and soldering (and covering with heat-shrink tubing) the wires to a six-pin segment of break-away headers. You can plug the header pins straight into your breadboard (we'll actually only be using three of the first four pins--ground, V+and tx--so if you want to use just a three-pin header you can.)

If you're planning to place the GPS module at some distance from the autopilot (like on the top of your plane's fuselage or on a wing, which is always a good idea to ensure the best reception), the cable construction process is a good time to splice longer wires on, too. Or, since we just use three of the six pins, you can use a standard servo extension cable, which fits the header strip and can plug into the Basic Stamp development board's servo port, just as easily.

All this is covered in more detail in this very handy tutorial. (The full series on that and code files are here). [UPDATE: that tutorial has an error in the EM406 pin diagram. The actual pins you need are 1 (ground), 2 (V+) and 4 (Tx). The proper instructions can be found here.]

Here's some Basic Stamp code I wrote that will test your GPS, displaying the NEMA sentences on your PC debug terminal. As always, change it if you're using a different pin for the GPS Tx (this code has it on pin 9) or if you're using a Stamp other than the BS2p (by modifying the "GPSBD CON 500" as instructed by the comments on that line)

The second thing you need to do is write a GPS parser to extract the data you need from these NEMA sentences for your autopilot code. Fortunately many have come before you, so you can just modify the code you need from this series of tutorials, or just roll your own. I haven't modified our own autopilot code yet to use this GPS module, but I'll get to that in the next week or so. [UPDATE: here it is]

Previous posts in this series:

Tutorial 1 -- Servos
Tutorial 2 -- Reading the Rx
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3D Robotics

The DIY Drones Mission (aka The Five Rules)

3689297692?profile=original"Because $10,000 $5,000 $1,000 is too much to pay for an autopilot, especially one that doesn't do exactly what you want."

An Unmanned Aerial Vehicle (UAV, colloquially known as a "drone") is basically an aerial robot. As we define it, it is capable of both remotely controlled flight (like a regular RC aircraft) and fully-autonomous flight, controlled by sensors, GPS, and onboard computers performing the functions of an autopilot. Our UAVs include airplanes, helicopters, quadcopters and blimps. Most of them are under five pounds, and some of them (especially the blimps) can be used indoors.

We are focused on non-commercial ("recreational") projects by amateurs, although pros are always welcome too. Reasons to make your own UAV range from a fun technical challenge, student contests, aerial photography and mapping (what we call "GeoCrawling"), and scientific sensing. We are primarily interested in civilian, not military, UAV uses here.

If you're new to all this, start here.

DIY Drones is a community based on the Ning social networking platform, and anybody who registers (it's free and easy) can post their own blog entries like this one on the front page, along with starting discussions in the sidebar at left or uploading videos below that. Your registration gives you the ability to do a lot on the site--so feel free to post anything you think will be of interest to this community!

There are other amateur sites out there, from the discussion forums of RC Groups to individual blogs, but DIY Drones is explicitly built as a social network, which means that the community is as important as the content. We're also focused on the most accessible end of the amateur UAV world, with the aim of potentially including high school students.

This means we emphasize amateur UAV projects that are:

  1. Simple: The aim of this project is to create new amateur UAV platforms, including those that could be used for a FIRST-like contest appropriate for students. While we're at it, we'll make amateur UAV development easier for everyone.
  2. Cheap: The target cost of all of our platforms is less than $1,000. You can buy a very good autopilot system for $10,000, but that's not our approach. Cheaper is better, especially with students and schools.
  3. Safe: We follow the current interpretation of the FAA guidelines on small UAVs. Recreational use (non-commercial), under 400 ft altitude, line of sight, "pilot in the loop" and onboard safety systems that always allow for manual control in the case of malfunction. We're building experimental platforms that demonstrate autonomy and the capacity to do real useful UAV work, but we test them in controlled settings. If you want to fly miles out of sight or map cities, we're going to assume you've got the proper FAA clearance or we don't want to know about it.
  4. Participatory: Share and others will share with you. That means that whenever possible, we open source our code and post it online. Everything on this site is published under a Creative Commons "attribution" license, which means that anyone can use or repost it, as long as they give credit to the original author.
  5. Civil: This is a community site of peers helping each other. Bad behavior, from rudeness to foul language, will be deleted. Generosity and kindness is often rewarded with reciprocal behavior and help.

Here are the full set of Site Policies:

  1. Civility is paramount. Treat others with respect, kindness and generosity. Some of our most expert members are people who were once total n00bz but were helped and encouraged by others, and are now repaying the favor with the next generation. Remember the Golden Rule. Don't be a jerk to anyone, be they other members, moderators or the owners. This is not a public park, and you have no constitutionally-mandated right to free speech. If you're creating a hostile or unpleasant environment, you'll be warned, then if it continues you'll be suspended.
  2. No discussion of politics or religion. This is not the place to discuss your views on the wisdom of military use of UAVs, any nation's foreign policy, your feelings about war, or anything else that is inclined to turn into a political debate. It is our experience that the rules for good dinner party conversation--no discussion of politics and religion--apply to online communities, too. DIY Drones aims to bring people together, and we find that discussions of politics and religion tend to polarize and drive people apart. There are plenty of other places to discuss those topics online, just not here.
  3. Ask questions in the discussion forum; inform others in blog posts. Submitted blog posts that are just questions and should have been posted in the discussion forum will not be approved. The moderators may or may not message you with the text so you can repost in the right area. To avoid losing your post, put it in the right place from the start.
  4. Blog posts are for informative topics of broad interest to the community. They must start with a picture or video, so the image appears on the front page on the site and gives a sense of the topic as well as inviting people to click in for more. Videos should be embedded (paste the embed code in the HTML tab, not the Rich Text tab). The post should also include links where appropriate. Don't make people do a Google search for what you're talking about if you can provide a link. 
  5. The Discussion Forum is for questions and tech support. We prefer to do all tech support in public, so that others can follow along. If you have a problem, please describe your particular system setup completely, ideally with a photograph, and pick the right forum tags so that others can find the thread later.
  6. No discussion of military or weaponized applications of UAVs. This site is just about amateur and civilian use.
  7. No discussion of illegal or harmful use of UAVs will be tolerated. Responsible use of UAVs is at the core of our mission. That means conforming with all laws in the United States, where this site is based, and insisting that our members elsewhere follow the laws of their own countries. In addition, we feel that part of our responsibility it to help the relevant authorities understand what's possible with amateur UAVs, so they can make better-informed policies and laws. So we have encouraged all relevant regulators, defense agencies and law enforcement agencies to become members here and even participate to help them do that, and many have. In addition, if we see any discussion of UAV use that we feel is potentially illegal or intended to do harm, we will bring it to the attention to the relevant authorities, and will comply with any legal request they make for information about users (although we don't know much that isn't public; see the next item).
  8. Promote safe flying. Moderators may delete postings that they decide are unsafe or promote unsafe activity. This is a judgement call, since it is also healthy to have public discussion about why certain activities are unsafe, but the decision as to whether to leave a post or edit/delete it is at the moderators' discretion. 
  9. Your privacy is protected, up to a point: This is a social network, so everything you write and post here is public, with certain exceptions: 1) Your private messages are private. Administrators are unable to see them, nor can anyone else other than the recipient. Members must not make private messages public without the explicit permission of everyone involved. 2) Your IP address is private. We are hosted on Ning, which controls the server logs. DIY Drones administrators can only see your username and email address; they cannot see your password and do not have access to your account.
  10. Do not publish personal emails or PMs without permission. This is a violation of expected confidentiality (that's why they're called "personal messages") and is grounds for banning.
  11. Do not type in ALL CAPS. It's considered SHOUTING. Posts in all caps will be deleted by the moderators.
  12. Absolutely no personal attacks. It's fine to disagree, but never okay to criticize another member personally.
  13. Share. Although we are not limited to open source projects, the ones that tend to get the most participation tend to be open source. Don't wait until your code or design is "finished"--post it as it is, and you may find that others will help you finish it faster. The best way to contribute is with your creativity--we love data, code, aircraft designs, photos of UAV projects, videos of flights and build logs. Post early and often!
  14. Keep comments open: Authors of blog posts and discussion threads technically have the option to close their comments or approve them before they appear, but we ask members not to do that. We want to encourage a free flow of conversation and blocking or delaying comments only interferes with that. The Moderators are standing by to ensure the conversation remains on-topic and civil, so please leave your comments open and let them do their job.
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3D Robotics
Harvard professor Robert Wood has demoed a robotic fly, which is the first to be both actually fly-sized and have a higher power/weight density than an real fly. From this good article about the project:

"...how to power those wings to beat 120 times per second? To keep this 60-milligram robot (the weight of a few grains of rice) with a 3-centimeter wingspan to a minimal size and weight, Wood says, you can’t simply use a shrunken version of the heavy DC (direct current) motors used in most robots. So he and his team settled on a simple actuator: in this case, a layered composite that bends when electricity is applied, thereby powering a micro-scale gearbox hooked up to the wings. Wood says the actuator works even better than its biological inspiration. The power density—a measure of power output as a function of mass—of a fly’s wing muscles is around 80 watts per kilogram; Wood’s wing design produces more than 400 watts per kilogram.

The first takeoff occurred late one evening last March, as Wood worked alone in his office, his colleagues gone for the evening. As the fly rose, Wood jumped up in celebration, quickly verified that his camera had captured the flight, and let out a sigh of relief."

Video:



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3D Robotics

DIY Drones Interviews

This is a list of interviews we've had with UAV/autopilot experts here at DIYDrones. Each is a multipart interview: Curt Olson, FlightGear and UAV simulation
  • Part 1 About Curt and the basics of using an open source flight simulator for UAV simulation
  • Part 2 (hardware notes, not really part of the interview)
  • Part 3: GPS simulation
  • Part 4: More advanced UAV simulation
  • Part 5 (more hardware notes)
Matt Chave, the CUAV project and magnetometers
  • Part 1: About Matt and the project
  • Part 2: About magnetometers
Dean Goedde, the AttoPilot (new commercial autopilot) project Dave Perry on UNAV and the PicoPilot autopilot: Martin Mueller and the Paparazzi project.

Andrew Bugera, University of Manitoba UAV Group, on the 2008 AUVSI Student UAV contest
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3D Robotics

Free autopilot code for the Propeller chip

If you're interested in Parallax's powerful 8-core Propeller chips, which are a huge step up from the Basic Stamps, here's some good news: a kind soul named Jason Wood has uploaded to the Parallax site a very complete Kalman-filtered IMU code object that uses the SparkFun IMU sensor head and this ADC. You plug the three components together, and the code gives you true Angle, Rate and q_bias. For those who have tried to write their own IMU, this is a Very Big Deal.

Basically, if you want to make a Propeller-based autopilot, Jason's done most of your work. No excuses now!


BTW, there are lots of other goodies in the Parallax object library, such as math libraries, floating point subroutines and PID routines.
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3D Robotics

DIY Drones UAV projects

Other active UAV projects on DIY Drones. (Please add a comment if you would like your project featured here.)

BlimpDuino, an Arduino-based autonomous indoor blimp

Multiplex Cularis (powered foam glider) UAV
  1. The Goal
  2. Camera Selection
  3. Packing it all in
  4. Autopilot
  5. Kit Mods
  6. Trial Balance

Multiplex EasyStar (smaller powered foam glider) aerial photgraphy platform:
  1. Modding for better performance
  2. Turning it into a camera platform

MRASV-3 (custom foam electric, with PicoPilot and Aerocomm transceivers)

Electric Heli UAV

Missouri University of Science & Technology UAV team's project

"Line Eye" electric power line monitoring UAV project

BasicX embedded processor autopilot project
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3D Robotics
The following are links to code, tutorials and discussion on DIY Drones about autopilots for different embedded processors, onboard computers and operating systems. Leave a comment if you have a project that should be added here.

Ardunio Platform

LEGO Mindstorms NXT
  • LEGO UAV, including autopilot code. Version 2, with a full 5 DoF IMU.
  • Another NXT UAV, using a full IMU with gyros and accelerometers and GPS

Parallax BASIC Stamp chip:

Parallax Propeller chip:

PIC processor
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3D Robotics

Jack Crossfire's UAV heli site and code

If you frequent RCGroups, you'll have encountered the wildly entertaining (and illuminating) near-daily posts of "Jack Crossfire", who's been chronicling his struggles in getting a very ambitious low-cost heli autopilot working. He has a site where you can learn more about the "Vicacopter", project and check out his source code. (You'll find his real name, which is no secret, in the code, and also how to contact him directly.) If you want to learn more about anything from Kalman filters to neural networks as they apply to aircraft control, his code is instructive, if a bit dense for mere mortals.

You can also see him interviewed in our PBS segment. It's fascinating to watch an ace engineer wrestle with some of the same issues that we find difficult, and because he's so focused on DIY and low-cost solutions, it's very appropriate for this site.
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3D Robotics
The folks behind the Australian Outback Challenge, an amateur UAV contest, have just posted a great video from their inaugural competition, held this September. It had two levels. The first, for high-school students, involved one team member controlling a R/C plane while another used onboard telemetry to guide the pilot over a target, on which they were supposed to drop a golf ball. The second, for university and above contestants, required a real UAV, with the aim of find a "lost hiker" (a dummy in the outback) and dropping a water bottle. Nobody successfully completed either mission, but my Californian neighbors at Dionysus Design came closest in the second category and won on points. Here's the video:
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