Teaser now up on the Arduino home page. Whatever could they be planning? ;-)
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Michael Oborne's awesome point-and-click APM mission planner now includes an APM cofiguration GUI. Nice!
The code is evolving quickly, so get it from the SVN repository for now. [UPDATE: it's in the download section as a zip now]
I don't know how long of a distance it takes for most of you to land, but when diving in below the treeline from 200 feet I pick up tremendousspeed on my EasyStar to the point of hitting 50 mph and overshootingthe runway, ending up in the trees.
Of course I can land in 500 feet easy, but making my autopilot do it wasnot. I was curious if anyone wanted to chime in on how they solvedtheir landing issues and minimizing the length of space required.
I was able to get mine down to 500 feet diving in from 200 feet and leveling off. The attached photo is my landing pattern.
1) Circle the landing zone, sample the winds
2) Go downwind
3) Turn for final approach
4) DIVE! with a feedback loop on airspeed able to do reverse thrust
5) flare and land.
My reverse thrust is done with a car speed controller. I can get +1 lbthrust as well as -1 lb of thrust. (Wasn't expecting that either.) Thisis just by running a typical 5x5 prop backwards!
The end result is that I slow down from 50 mph to 20 mph in a few seconds after the dive.
AttoPilot International has a sweet deal for current AttoPilot 1.8 owners: just $300 to upgrade to 2.0. Why do it? Well, just look at this picture. That's some pretty amazing miniaturization! Smaller even than ArduPilot without its shield. Plus the AttoPilot folks upgraded my 1.8 unit to 2.0 software (actually, they did even better--they replaced it with new hardware because it was broken), so now I essentially have two 2.0 units. Best customer service ever!
The growth here is accelerating. We're now adding 1,000 members every 8 weeks and hit 11,000 today. On an average day, this site does between 25,000 and 30,000 page views. We're closing in on 1 million page views per month.
I had lunch today with the executive team of Ning, the social networking platform we're based on. Features coming out over the next several weeks include:
- WordPress-style blogs. Much better authoring tools and design flexibility in the blogs, and across all text entry areas.
- Badges and better community feedback options for content. Thumbs up/thumbs down rankings, and the ability for community stars to emerge and get recognition. "N00b Ninjas" FTW!
- More design flexibility. The fixed-width columns and fixed-width overall site will soon be a thing of the past.
- Improved Leaderboards. We'll be able to get much more granularity in figuring out what and who is popular here, so the moderators can spot and reward great contributors more easily.
"4.2 Apps that use location-based APIs for automatic or autonomous control of vehicles, aircraft, or other devices will be rejected."
The incident report on this one should be really interesting.
From the official military press release.
Admiral Sandy Winnefeld, who oversees the country’s air defenses, said the August 2 incident presented senior officers with an unprecedented dilemma, as a robotic Fire Scout helicopter strayed off course after losing ground communications.
“We were watching this very closely,” said Winnefeld, head of US Northern Command and NORAD, the joint US-Canadian air defense command.
“It’s headed right for the heart of the national capital region,” he told defense reporters. “Do you let it run out of gas and hopefully crash in a farmer’s field or do you actually take action to shoot it down?”
“You certainly don’t want to shoot it down over a populated area if you can avoid it.”
The North American Aerospace Defense Command was on the verge of scrambling F-16 fighter jets to intercept the helicopter when operators regained control of the chopper after 20 minutes.
Long time - no sea.
If anybody will tell me about global warming - i will kill him!
We had the coldest (and rainiest) may and june ever.
And August was - the rainiest ever.
Globalization only seems to work in the financial domain, but not for the weather. What about a "weather-transfer" of bad weather to the sahara? They will appreciate the rain there. Despite this fact and the passing away of a close relative, i wished, these months had never happened.
In mid-july, we have seen that this spherical fusion-reactor some eight light-minutes away is still running. I am personally not a fan of nuclear energy, but in this case...
What happened since my last entry?
Not really much.
The new cat has now the same color on both hulls.
The board, that holds the hulls together is now coated with fiber and epoxy to make it more rigid.
The extra battery for the sonar was dropped. The power comes now from the main battery. (-300g of weight)
The cable from the sonar to the transducer was shortened (-100g)
This was really not much, but there are still some challenges out there...
Swimming is not one of my favourite disciplines.
Swimming in bad weather conditions does not even make it better.
Swimming is OK, considering the following conditions:
1. It is summer (I mean that season, when it should be really warm)
2. You have enough time to put on your swimming suit, when the boat starts to react weird.
3. You love swimming
4. No rain
if any of the above is not applicable, staying on the shoreline is the better option.
Swimming is usually caused by:
1. Software
2. Mechanics and Hardware
3. Personal idiocy
4. A combination of the above
To prepare the this year "PID optimization campaign" i decided, to reduce my recovery-swimming exercises to a minimum and thought about Radio Control.
First, i fiddled with my 27MHz RC control from the Jetski model, but found out that this thing is abolutely crappy. Bad range performance, noisy and most of all: no failsafe behaviour. I wanted the software on the ardupilot to decide, whether there is a transmitter controlling the ship or not. And therefore i have to measure the pulses comming out of the Receiver. So far so good, but the 27MHz Rx outputs always some pulses, regardless, if the Tx is on or off (the good old analog era...).
I remembered, that the Ardupilot was originally conceived as a fail-safe
system with an RC option as a fallback for the safe launching and landing
of an airframe.
Why not using this feature for the boat?
Reading the docs and the software showed, that the implementation, which is
in the original version of the Ardupilot was not exactly what i needed.
My requirements were:
1. If the transmitter is OFF or the Receiver is out of reach, the boat shall
be fully controlled by the Ardupilot.
2. If the Transmitter is ON, control shall be passed to the Radio control.
Implementation on the original version was a little bit different,
so i decided to do it my own way.
How to detect if the RF is good or bad?
The only way is to look at the servo pulses, that come out of the Receiver.
Analog RC Systems output always something on the servo channels, even when the Tx is OFF. (see above)
Discrimination between noise and a good signal would be possible by some weird SW algorithms, but i wanted to keep it simple.
A very old friend of mine, who is an RC Dinosaur told me to buy a 2.4GHz RC control.
So i ordered a SPEKTRUM DX5e, which is a fairly priced entry level model.
Reading the manual showed, that the failsafe functionality of the receiver was exactly that what
i needed. Manuals sometimes do not tell the truth, so i oscillographed the servo outputs and found, that
they really told the truth:
1. When the receiver is turned ON without a Transmitter beeing in the air, there is silence on all servo outputs - good.
2. When the Tx is turned ON and the Rx is correctly bound to the Tx, pulses on all channels - good.
3. When the Tx is switched OFF, silence on all channels, but not on the throttle. The throttle channel outputs a pre-programmed default pulse-width. - still good.
From the software point of view, it is very easy to distinguish between silence and "something". So i took the rudder channel to sense the RF.
(Tx ON --> pulses, Tx OFF --> silence)
Technically, all worked fine.
right in the middle: the Receiver.
I have put the code here:
Please note, that the Hardware of the Ardupilot board has to be
modified!
Read the comments in the RC_Control tab.
I have refactured some of the code and added some comments.
WITHOUT testing it. Take the code as a starting point for your own
experiments.
Thats all for today, on the next episode i will tell the experience with the RC control on the lake and why i decided not to use the RC any more.
I finally went with a Trex 600 ESP, stretched it to a 700e and mounted a canon 50D.
thanks
Matt
More goodness from the Laboratory of Intelligent Systems at EPFL in Switzerland: 10 Zagi-style UAVs autonomous flocking at the same time. From the write-up:
Designing swarm controllers is typically challenging because no obvious relationship exists between the individual robot behaviors and the emergent behavior of the entire swarm. For this reason, we turn to biology for inspiration.
In a first approach, artificial evolution is used for its potential to automatically discover simple and unthought-of robot controllers. Good evolved controllers are then reverse-engineered so as to capture the simple and efficient solutions found through evolution in hand-designed controllers that are easy to understand and can be modeled. Resulting controllers can therefore be adapted to a variety of scenarios in a predictable manner. Furthermore, they can be extended to accommodate entirely new applications. Reverse-engineered controllers demonstrate a variety of behaviors such as exploration, synchronization, area coverage and communication relay.
Our long national nightmare is over: The ArduPilot Mega main board is back in stock. Sparkfun has 164 on hand, and more will be built as these go. The IMU shield is also in stock at the DIY Drones store, as are both the MediaTek and uBlox GPS modules. So basically everything you need is now available.
The code is in good shape in Alpha release (SVN only) and is being flown regularily. It will be released in public Beta (zip file) for less expert users by the end of Sept. The ArduCopter branch is also flying well, and should be ready for the commercial release of the full ArduCopter kit in about a month.
From BotJunkie:
"Part of the appeal of flapping wing micro air vehicles is that (unlike helicopters) they offer some resilience against crashing into obstacles. Crashing is still bad, though, and (with some exceptions) significant damage to things that fly generally keeps those things from continuing to be useful. To mitigate this, Harvard University has developed an itty bitty differential to keep a pair of wings (say, on arobot bee or robot fly) generating the same amount of torque, even if one of those wings is damaged. The beauty of the PARITy differential (Passive Aeromechanical Regulation of Imbalanced Torques) is that it’s completely mechanical, and simply due to its design it will (for example) increase the flapping speed of a damaged wing to match the torque output of a paired, undamaged wing. Basically, it’s the same kind of thing that you have controlling the power to the wheels in your car, except about a million times smaller."
I'm starting to build my own quadcopter. I'm a newbie in UAV world so I'm trying to understand all the concepts behind with this project.
I started from scratch building my own IMU and all the control (I don't have a RC system yet).
Here are my specs for now:
Control Board:
- Arduino Mega
- 3 LY530AL gyros
- 1 ADXL330 accelerometer
- 1 XBee Pro module
Mechanical parts:
- 4 AX 2308n 1100kv rotor
- 4 Flying 20A ESC with BEC
- 4 8x3.8 SF Regular props (well... I cannot found pusher props here so I will use the Jose Julio's idea to turn some degrees in front and rear rotors)
- 3000mAh 3S mystery battery
I'm sure I have miscalculated something but for now, if it hover with some stability and control I'll be happy.
Nothing is working for now, but I did some tests with rotors and ESCs (breaking one rotor in the process).
Here are some pics of the frame and mounting:
All the photos are posted on my profile and as soon as I get the other photos with my brother I'll upload than.
Nice little photo tour here:
http://www.popsci.com/technology/gallery/2010-09/gallery-scenes-drone-trade-show
What a cool platform, its already been approved for manned flight so not much of a leap when it comes to jumping through unmanned hoops.
http://www.suasnews.com/2010/09/1056/electric-cri-cri-takes-flight/
I am continuing the ArmQuad software development.
I believe that soon I will release for FREE a ACRO software version with current (or improved ) performance that can be seen in these 2 videos.
Un saluto agli Italiani presenti in questa community.
From their site:
Feature List:
- Plug-N-Fly - just hookup to your quad and fly. No calibration software and no tweaking needed.
- All boards come fully assembled. The HoverflyPro is precision
manufactured. Sensors are the smallest on the market and the entire
board is assembled by pick-and-place robots.
- Features 2 Parallax Propeller MCUs that provide a total of 16 microprocessors running in parallel for the fastest data collection and
control of your Electronic Speed Controllers (ESCs).
- MCUs operate at 80Mhz for a total of over a GHz of processing power.
- Operates with Brushed or Brushless motors.
- Support for standard PWM Speed Controllers (I2C is not required).
- On-board voltage conversion switches automatically for 5.0V or 6.0V ESCs.
- UltraPWM technology means better stability. The PWM signal is compressed to achieve a faster update rate without using I2C ESCs.
- Scalable Control - Use any size motor or frame. HoverflyPro is capable of running very large motors.
- Not limited to tiny cameras. You pick the motors, battery and frame for the payload you want to carry.
- On-board voltage regulation. Input power range 6V-15V.
- Direct USB programming. No need to connect flight battery for
programming. Use the Windows update client and any mini-USB cable to
connect to the HoverflyPro. Programming clip no longer needed.
- Position holding gyros on all axes.
- FREE software upgrades. Windows update client notifies you of software updates. A simple USB connection provides quick and easy
software updates.
- You choose the configuration. Quad, Hex, or Octo. In Quad configuration you can pick "+" or "X" orientation.
- Altitude hold via barometer / accelerometer
- Auto leveling
- Automatic Pitch,Roll compensation for video and still cameras.
- Built in control for pan/tilt when in altitude hold mode
- Simple to use. Comprehensive instructions to ensure your success.
- Use any receiver and transmitter. HoverflyPro automatically senses and uses any PWM input.
- Basic and Aerobatic mode. Basic uses accelerometer to keep the quad level when the sticks are centered. It limits the maximum bank
angle achievable. Aerobatic allows the user to rely on the gyros only
for stable, but more extreme performance.
Detailed Specifications
- 2.75" x 2.75" (70mm x 70mm)
- Board height - < 0.5" (12.7mm)
- Programming power - USB or flight battery
- Flight battery - Input power range 6V-15V. Power connection is symmetric (no wrong way to connect power).
- 8x Receiver inputs
- 8x ESC outputs
- Camera Pan/Tilt outputs for camera mount stabilization
- 2x Future outputs (3-pin)
- On-Screen Display (OSD) input and output (3-pin).
- Buzzer
- RGB LED
- XYZ Digital Gyroscope
- XYZ Digital Accelerometer
- Pressure/Barometric Sensor
- Expansion Interface (12-pin)
- ESC voltage conversion output module
- Flight Battery voltage level sensor (for OSD and emergency modes)
- Programming switch (2-position). Base program and advanced feature programs required during update.
- Manual Gain adjustment (potentiometer)
