Blogs

All Posts (14056)

Sort by

Huddle Issues Anyone?

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

Modularity, Versatility, Affordability

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

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

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

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

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

Read more…

Paparazzi I2C programming

Posted by Jano Visser on October 23, 2009 at 2:46am
Good day everyone,I am working on a uav project at university. We want to integrate ultra sonic sensors with the paparazzi to use for auto takeoff and landing. We want to do this by using the I2C port. Does enyone know how one would adapt the source kode of the paparazzi in order to do this?Thank you.
Read more…
Developer

Store Updates!

Posted by Jordi Muñoz on October 22, 2009 at 4:26pm

UPS is now available as shipping method and we also have something called "negotiated rates", in other words i have to punch in the face a few UPS guys in order to get cheaper shipping prices (like SparkFun!). Before this ship something to Japan via UPS Expedited used to cost 60 bucks! and now is around $30 dlls!! (you save 50%). In hope in the future costumers will start using more UPS for large and expensive shipments, is more secure, is a lot faster, every package is insured, has live tracking number and they have funny brown trucks.Schematics and diagrams are now available for all products (i guess)....We carry new stuff and i re-organized the products, so please come and visit us!:http://store.diydrones.com/Regards!
Read more…
3D Robotics

Progress report from the DIY Drones development teams

Posted by Chris Anderson on October 21, 2009 at 9:00pm

The dev teams are making great progress in the various Huddle workspaces. Above is just one example: the prototype enclosure for ArduStation 2.0. Looking good! Other teams that are making good progress include the ArduIMU manual (almost done) and the turn-rate limiter autopilot shield (components selected, starting on board design). Crowdsourcing works!
Read more…
3D Robotics

Harvard developing robot bees

Posted by Chris Anderson on October 20, 2009 at 9:16pm

From BotJunkie: "The National Science Foundation is giving Harvard a cool $10 million to develop a robot bee colony. That’s right, not just one, but an entire colony of robot bees. The bees will buzz around on flapping wings, use optical flow sensors for navigation and obstacle avoidance, sport cute little antennae as well as “pollination and docking appendages,” and use an as yet unspecified power source." We have got to get an optical flow community building here. All it takes is an old optical mouse to get started, as we discussed here!
Read more…

Paparazzi help!

Posted by Jesus on October 20, 2009 at 3:00pm
Hello!!I´m very interested in the paparazzi uav ans the booz (quadcopter). But I have some questions that I wish that anybody could answer it.1st- It´s possible to use the modem like a rc systems, for example connecting a gamepad to the laptop?2nd- Which knods of sensor can be connected to the analog inputs? Are there code prepared for that?3rd- Is ther a "newbie" guide to start in the paparazzi uav?4th- It´s possible to control the booz with the laptop?5th- The booz have autonomous navigation (with on air update waypoints?6th- It´s compatible with the paparazzi ground station??7th- Is ther a guide for the booz?8th- IS there a update forum of the paparazzisystems?Sorry for my "question attack" but I´m newbie with this systemsThanks for all.Yours faitfullyJesús
Read more…

Closed loop autopilot simulation with FlightGear - Part 1

Posted by Faisal Shah on October 19, 2009 at 10:30pm
I don't have the cash right now to buy a plane, ArduIMU, an auto pilot, and associated hardware. So, while I'm saving for the hardware, I want to play with the various algorithms out there in a simulation environment - to gain a deeper understanding and feel for it. I want to be able to code in C, so I can use the code directly in the hardware autopilot when I reach that point.I want to use a flight dynamics model to generate sensor inputs to the autopilot (3 axis gyro, 3 axis accelerometer, GPS - just like ArduIMU), and have the autopilot generate control surface inputs to the simulated plane in the flight dynamics model.Phase 1: Open loop. Tuning/experimenting with the AHRS algorithm. This would not require the flight dynamics model to accept control surface input from the autopilot. I would load the simulation and fly an airplane around in some pattern. The FDM would generate and log the sensor readings and the "ground truth" pitch-roll-yaw angles. My AHRS code would read in the sensor log, compute the pitch-roll-yaw angles, and would allow me to compare it with the "ground truth" data generated by the FDM.Phase 2: Close the loop. Use the autopilot to accept sensor inputs from the FDM, and send back control surface inputs.Right now I'm concentrating on Phase 1. Has this been done before? I've looked around a bit and it seems that FlightGear is well suited for this type of hackery. Are these properties the ones I should use to generate the correct sensor data, emulating an ArduIMU? How can I get the values I need out of FlightGear (I read that a UDP socket is used?).*Gyro sensors*/orientation/roll-rate-degps/orientation/pitch-rate-degps/orientation/yaw-rate-degps*Accelerometers*/accelerations/pilot/x-accel-fps_sec/accelerations/pilot/y-accel-fps_sec/accelerations/pilot/z-accel-fps_sec*ground truth data to be logged and compared with my own AHRS output*/orientation/roll-deg/orientation/pitch-deg/orientation/heading-degHow does everyone here test their algorithms before sending it up in the air? Anyone else run their autopilot code in a closed loop with a flight dynamics model? If not, I wouldn't mind putting in some extra effort to make this interface nice/easy-to-use so that it can be used by the community out of the box for autopilot testing.Thanks in advance!
Read more…

French micro plane fast forwards to hover

Posted by isobot on October 18, 2009 at 4:59pm
Hope this is not a duplicate post (I've seen it before somewhere)A mere 30 centimeters long, the MAVion combines fixed wings with two counter rotating propellers, allowing it to operate with high aerodynamic efficiency--even in adverse conditions, according to the professor.thought this might be of interest.http://news.cnet.com/8301-13639_3-10377358-42.html?part=rss&subj=news&tag=2547-1_3-0-5

Read more…
Developer

My UAV helicopter - vibration problems

Posted by Randy on October 17, 2009 at 10:58pm
Hello All,Like a few others, I've been working on a UAV Helicopter but I've hit a bit of roadblock and I'm looking for some helpful advice from the community. At the moment, when I try to fly the helicopter (so far as high as 4 inches off the ground), it tries as hard as it can to bank left because it thinks it's leaning at >40%. The problem is vibration and I'm looking for any advice I can get on how to overcome this problem.Below is some slightly massaged data from the accelerometers and gyros. The accelerometer data is adjusted back to "mid" so instead of values being from 0 ~ 1024, they're from -512 ~ +512. The gyroscope data has been converted into degrees per second (i.e. (raw gyro value - gyroMid)* magicNumber). The little table of numbers below the graphs is the average variation in accelerometer values I'm seeing..so when the helicopter is completely assembled, each x-axis acclerometer values is on avarege 300 away from the previous value!

I guess there are two roads to resolving this:1) reducing the actual vibration of the helicopter.2) use less vibration sensitive accelerometers and gyroscopesFor #1, I've done some loosening of the ball joints in the main rotor and upgraded some components to Aluminum and Graphite.For #2 I haven't done much. I'm using Sparkfun's 6DOF (http://www.sparkfun.com/commerce/product_info.php?products_id=8454).What do you think? All advice more than welcome.BTW, I've also been following John Mac's and Bill Premerlani work on CCPM Helicopters so I'm thinking of contributing to their efforts instead of going it on my own.

You'll see from the pic above I've incorporated a number of improvements suggested from my previous blog post including:- better mounting of the AVR 128 and sparkfun 6DOF (now on the back)- lipo batteryI've also upgraded the engine to a hyperion Z3025-06 because the previous one simply couldn't get this big-ish ECO8 off the ground. I've also replaced the "mechanical mixing" with "electronic mixing" -- this is ECO8 speak mostly I think but basically it means that now the three servos at the back, work together to control the pitch, roll and elevation of the main blades instead of using the ECO8's manual mixer thingmy which everyone says doesn't work very well.
Read more…

Above Sunnyvale

Posted by Jack Crossfire on October 17, 2009 at 10:30pm
Found a few safe landing zones in North Sunnyvale to lift off from. 1 area is closer to the subject of interest, but with higher risk of getting jammed.

Had a day job here in 2000, in a building which has since been destroyed& replaced. Our old man worked across the street in the 80's.

He got busted 4 trying to photograph a satellite dish near this bluecube. Now it's probably going 2 B torn down. Fly near it & U will be jammed.

Towards San Jose

400ft feels really low. Not likely to get any higher in this area.
Read more…

Best way to calibrate a pitot / Good way to estimate wind?

Posted by Tj Bordelon on October 17, 2009 at 4:06pm
I just added a pitot to my ezstar (http://bordelon.net/ezstar) and did a flight. Naturally the plots of the airspeed sensor and GPS velocity (projected onto the X axis... straight thru the nose) did not seem to match. But should they? I figured any wind would skew the results, so how do you know you're calibrated?I first tried to make a "manometer" with a tube of water but that seemed to just make a mess and was off by 50% in the end.I finally just flew with the manometer guess, and made 10 or so circles in the air. On landing, I took the data and scaled things to match as best as I could. Here's the result:

So they don't match. But there was a slight breeze that day. I then had an idea! What about plotting the wind speed (pitot - gps) vs bearing. I dumped a bunch of points to the plot and got this:

Mind you it wasn't symmetric about 0, so I played with the scale to make it so. I believe this was the best and most accurate thing I did to calibrate. Because once I did this, I then went and flew in 20 mph winds... and guess what! I got this:

I also verified that the direction of maximum/minimum "wind" was the exact bearing and speed of the wind I measured just before takeoff.So what's the problem? Well, I talked to a few guys I used to work with on a UAV project and this just confused them. So I figure I"d ask you guys out the'e what you do to make sure your pitot is calibrated, and if any of you have a good method for wind estimation. Does my technique look like what you do?
Read more…