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3689503317?profile=original

Hi guys, 

I got permission from my customer to share this story.  

The quad is a DJI Phantom, RTF in 10 minutes when you get your box delivered to you. yes no kidding, it's that simple. 

Of course this kind of product brings a lot of new beginner customers (as well as experienced one looking for a small form factor and easy of flying). 

So here is the story of this customer 4-5 flight, in a super wide open area, safe, really safe for experimentation. 

This is the video of the "trigger failsafe to save my $$$" event. 

Why I post this? 

I really think we should go in that direction for the APM failsafe out of the box. Granted we have more options but complexity and flexibility is not a reason to not have a basic default behavior even if not set in mission planner (for these beginners not reading instructions!) 

(below it is the text version of what was going on his mind.)

Enjoy! 

Dany

CanadaDrones

I didn't know what had gone wrong.  I was baffled and confused when it 
all went wrong so suddenly.  It was only while studying the video later 
that I figured it out.

I normally fly in GPS mode.  That's pretty much idiot-proof as long as 
the Phantom has a good satellite-lock.  But I had switched to Atti mode 
to experiment with improving video smoothness.

You can tell from the video it's in Atti mode.  I flew past my wife at 
high speed, then levelled off and swung it around to point back.  If it 
had been in GPS mode, it should have stopped by itself and hovered in 
that spot.  But in Atti mode it kept right on sailing further away, 
still at fairly high speed.

The problem was that it was such a bright sunny day, with bright snow 
and black trees in the background.  As it drifted even further away from 
me I wasn't sure and couldn't see anymore which way it was facing.  So I 
switched to Home-Lock and pulled back on the stick, thinking that should 
bring it straight back to me regardless of which which direction it was 
aimed at the time.  That was the plan anyway.

I didn't realize that Home-Lock doesn't work in Atti-mode.  I'd never 
tried that combination before.

So, when I pulled full back on the stick, the Phantom responded (quite 
properly) by backing up even more quickly away from me.  And that REALLY 
surprised me, because I wasn't expecting that at all.

At that point I should still have been able to figure out what was 
happening and recover.  But I was so stunned by this unexpected 
reaction, I just didn't know what to do.  I looked down at the 
transmitter to confirm it was actually in Home-Lock mode.  But when I 
looked back up I couldn't even see the Phantom anymore.

Last I saw it, it was heading for the trees across the lake.  So my only 
thought was to add throttle to ensure it clears the trees.

It was much too far away from me.  Did it just go out of transmitter 
range?  Maybe.  But fail-safe should have kicked in automatically then. 
 Did it lose satellite-lock?  If that's the case, then I'm really in 
trouble because I can't even see it anymore to control it manually and 
it might already be headed on its way back to China right now.

I was undecided about turning off the transmitter to force a fail-safe 
return to home.  If it has lost satellite-lock, then turning off the 
transmitter will kill any slim chance at all of my regaining control. 
But I didn't know what else to do.

Turns out, as you can see from the video, I had a solid transmitter 
connection the whole time.  I should have simply switched to GPS mode. 
Then Home-Lock would have worked perfectly.

But in panic, I switched off the transmitter, and instantly fail-safe 
kicked in and saved my butt.  But, it had already been flying for ~6 
minutes, and I was worried it was going to run out of battery time 
before I could get it back to the ground.

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Major Technology Patent Case Pending

3689503049?profile=original

A federal appeals court is about to review a case with broad implications for abstract technology patents. 

From BusinessInsider:

"Alice, based in Melbourne, Australia, and owned in part by National Australia Bank Ltd, holds a portfolio of patents, including four that cover a computerized system for exchanging financial obligations. The company argues that when an invention requires the use of a computer, even if it involves an abstract idea, "it's patentable if the computer plays a significant role in the invention.

Many technology and Internet companies worry that too many patents have been granted for simple ideas, hindering others from building innovations using those principles. They say this slows technology development, though other companies, including smaller developers and individuals, say inventors deserve legal protections for their innovations.
Google, Dell Inc and Facebook filed a friend-of-the-court brief criticizing the appeals panel's earlier decision.


They wrote that "bare-bones patents" like Alice's do not innovate enough on their own to deserve patent protection. "The real work comes later, when others undertake the innovative task of developing concrete applications," they wrote.


LinkedIn Corp, Twitter and others also submitted a friend-of-the-court brief, arguing against too much leniency in granting patents, though they did not pledge support for either side in the case.


International Business Machines Corp, on the other hand, filed a brief saying most software inventions qualify for patent protection. IBM, which has topped the list of U.S. patent recipients for 20 years, cautioned the court against creating a strict rule that would further limit protection, though it did not side with either party in the lawsuit."

more detailed & formal synopsis here hints at how out of their depth judges are when ruling on such technical issues

related hilarity over at Dangerous Prototypes

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3D Robotics

Roboticst/artist Natalie Jeremijenko spoke at Google's "Solve for X" conference on using technology to solve big world problems, in this case "drones for good". I'm not sure she came up with anything particularily new, but thought it was worth sharing here all the same.

From the video description:

Problem: What if war could be fought using technology that's more humane and could acheive political or tactical goals without killing civilians?

Solution: Targeted military force could do limited harm or potentially do good instead of the drone missle strikes that are used today.

Technology: Natalie proposes unmanned aerial vehicles (UAVs) could be used in new, creative ways.

(Hat tip to Sonal Chokshi for the link)

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3689503035?profile=original

I was wondering how long it'd be before someone did this... The early stage involves minimal lift capability, but eventually 1000kg -- goods and people.

The MatterNet on FastCompany

Surprisingly "The team's prototype (pictured above) can already do this, but its autonomous capabilities have not yet been tested." -- I would think there are loads of hobby quads that are ahead of this one, then?

I've had dreams of doing this with rovers (of various sizes) of course the issue being the lack of roads... 

Direct link: http://matternet.us/

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3689503102?profile=original

SWR is one of those things that most people don't need to worry about.  However, when you start building your own antennas or need to get every mw of power out of your existing antennas, you might need to check/tune your SWR.

The Wikipedia article does a good job explaining what SWR is, but in a nutshell, it's the efficiency of your antennas coupled with your transmitter's frequency. An antenna that is a poor match for a specific frequency will be less efficient at transmitting that frequency and reflect some of that energy back to its source.  A SWR meter measures two things, forward, and reflected power; these two things together tell you what your SWR is.  SWR is measured on a exponential scale with 1 being the best, and anything under 2.5 being consider good.  Most store bought FPV antennas will be around 1.2.  I use they highly recommended DAIWA  CN-801 SII, which can measure 0.9 to 2.5 GHz.

To get started I'm going to connect my ~300 mw 1258 MHz video TX and an Ibcrazy 4 lobe antenna (which cannot be tuned).  Because of the scale on my meter, I put a 10 db attenuation on which puts the needles in a better place to read, however this hides my true forward power.  I'll remove it later to see how much power my TX is actually putting out.


3689503124?profile=original

When I turn on the video TX (no video signal required), I can read my SWR for this antenna by looking at the point the two needles cross.  This antenna is great with a SWR of ~1.2.

3689503078?profile=original

As I said before, this type of antennas can't be tuned (unlike say a dipole you could change the length on), however we can place an object in the antenna to see a similar change.


3689503140?profile=original

Now when we measure the SWR is worse.  Looks to be ~2.15.  Notice how the reflected power has gone up.  That means with some bulky object causing a short, it's reflecting more power back and not transmitting the full power of the TX.


3689503100?profile=original

Finally, we remove the 10 db attenuation to check the power output of my video TX.

3689503172?profile=original

And it's actually a little bit better than 300 mw it was sold as.  Not bad.


So even if you're not going to be tuning your own antennas anytime soon, it's important to remember that you should always try to improve your antennas before you start throwing power at a problem.  That 1W video TX might only be outputting 400 mw.  Also, if you're using something that is frequency hopping, generally you would tune your antennas for the middle of the band.  A good SWR meter also tells you how much power you're actually transmitting which is always helpful.  

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L. Meier about Open Hardware phenomenon:
"It's base technology like science, it just basis for many things "
A bit rough and chaotic, but very interesting presentation and opinions from a well-known developers of OpenHW UAV/UAS solutions.

First haltime dedicated to perspectives of 3D printing technology for OpenHW UAV production,
second contains several issues of the general development OpenHardware technology (much more interesting)

Note about Lorenz Meier person from http://www.inf.ethz.ch/personal/lomeier/

He is PhD student working on mobile localization 3D reconstruction on smartphones and micro air vehicles. He started her current project, PIXHAWK, in 2009 as a master student. It is about autonomously flying small helicopters. He participated in the sFly EU research project 2011-2012 and currently also working on realtime 3D reconstruction on mobile phones. He contribute her spare time to the PX4 autopilot platform.

He's maintain and contribute to a number of open source projects.

  • QGroundControl - an user interface (GUI) to small unmanned aerial vehicles. Main developer / maintainer
  • MAVLink - communication library for small-to-large robotic vehicles. Main developer / maintainer
  • MAVCONN - Linux/Unix/Posix middleware for micro air vehicles, uses MAVLink as message format. Core developer / maintainer
  • PX4 Autopilot - High-perfomance, open hardware/software, low cost, POSIX inspired autopilot (PX4FMU) for micro air vehicles. Core developer / maintainer


Source of video ZURICH.MINDS YT channel www.youtube.com/user/zurichminds posted Dec 28, 2012

The diagram in the beginning represent Hype_cycle of Technologies.

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Developer

3689502944?profile=original

I have my Turnigy 9x Radio flashed with Open9X and it is configured to be able to select 6 different Flight Modes as instructed in this post

It was requested recently "Can you can display the selected Flight Mode of the APM on Open9x main screen?" e.g Manual, Stabilize etc..  I've been trying to understand RC programming recently and this looked like a good exercise to see if I had learnt anything. 

What I understood was Flight Phases built into Open9x can be named, they can be activated by assigning them to a state of a real switch. The problem is that you cannot just check the 3 position switch to see if it's in position of ID0, ID1 or ID2 you have to cope with a modifier such as AIL or T-CUT. To solve this issue you can use internal 'custom switches' that activate based on logic rules. ie. if AIL and ID2 custom switch 6 is enabled, you can use this custom switch to enable the Flight Mode with the correct name.

The first thing I did was set-up six Custom Switches that corresponded to each combination of AIL and the 3 position switch. (i.e IDO, ID1, ID2)

e.g.

CS1 requires !AIL (not aileron) and ID0

CS2 requires !AIL and ID1 etc..

3689502944?profile=originalAs you move the switches  you should see in bold each combination as it is actuated.

Now move to the Flight Phases Menu. Here you need to assign a switch to each phase (I assumed the default FP0 was CS1, so nothing to assign)

for FP1 press menu and then assign CS2 to switch, and name it the Flight Mode that MP tells you are in. (In my case Circle)

Also make sure that the Trims option is set to 0000 (it read RETA by default) this means that the Flight Phase copies your standard trim values from FP0. 

The screen shot below shows how i set my TX up

3689502895?profile=original

Notice that FBW is from CS7, this is since I amalgamated  FBW-A and FBW-B (CS5 & CS4) under the same title since they are similar and there are only 5 flight phases. That means if either are selected CS7 is enabled. (maybe a mod to Open9X is required ;-) )

Once you have all your modes programmed, check against mission planner that what you are requesting on the TX is what mode the APM will switch too.

And that's it really, a simple way to program Open9x to help remember the modes you have programmed on the switches.

Here's some screen shots of the final outcome.

Hope this is helpful; :-)

 3689502746?profile=original3689503006?profile=original3689503059?profile=original

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Pending Californian "Drone" Legislation

images?q=tbn:ANd9GcTRLa9nVm2iqzgSt__KTtAwdqP8ImPG2_I4JKt59VZgzRL7x8fVy_4j2M8OThis may or may not be old news, but I thought it worthy of a post since many of us reside in this lovely state (including 3DR):

http://sd20.senate.ca.gov/news/2012-12-03-senator-padilla-introduces-bill-regulate-drones-california

http://legiscan.com/CA/text/SB15

While I am hopeful that this doesn't result in a blanket restriction of all personal RC's with cameras, etc, recent fear-mongering trends in the media have me thinking pessimistically.

I encourage anyone who could be affected (remember: how CA goes, goes a lot of the US - especially concerning the media and film industry) to consider writing to this state senator.  http://sd20.senate.ca.gov/contact

Positive reinforcement from this community could go a long way in setting up the fledgling non-military UAV industry for the long run.

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AR Drone 2.0 Search and Rescue

3689502884?profile=original

I have found a project that uses 299.00 AR Drone 2.0 as the platform for search and rescue missions. This is a very good example of UAV for good uses at toy prices. 

Details about the project are here: http://paparazzi.enac.fr/wiki/TU_Delft_-_Search_and_Rescue_with_AR_Drone_2

They have even posted fully autonomous flight videos that look very promising. No need for another expensive autopilot this is a repurpose of the existing hardware inside the AR Drone 2.0.

I'm surprised I did not read about it here first on such a comprehensive website dedicated to information like this. I am happy to be the first to share this information with everyone. Enjoy. 

The TU Delft Team.

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Quadrotor Flight computer FLCv2p0

3689502906?profile=original

This is my first post in DIY Drones. I would like to share with the comunity my last work related to UAVs. I'm currently working on my thesis for graduation as an electronic engineering at the University of Buenos Aires. My thesis is based on a embedded control system and in this post I'm presenting the Flight computer that holds the control algorithms. 

My thesis is more an academic research than a hardware/software project, but I decided to do my own powerful board to test it. 

Above is the FLCv2p0 (Flight computer v2.0). The first version was a homemade attempt and now this is the new version

These are the details of the board:

  • LPC1769 Cortex M3 @ 120 Mhz microprocessor wtih 512KB of flash and 64 KB of RAM
  • Two side PCB board with mounting holes (almost) compatible with DJI Flamewheel frame
  • 4 intefaces for arms: this is a ESC output and a multipourpouse input output conector with servo pinout that serves as output or input in digital, analog, or Timer capture mode for measuring frecuencies and periods (ideal for tachometers)
  • 2 other arm interface without connector for 2 extra motors
  • Two power options: USB for developing and testing and an external input (the blue one) for direct battery input. Up  to 40V can be input, then there is a stepdown high effiecncy switching regulator that regulates to 3.3v needed for all the board. There is no need for BEC (the +5V pin of the arms is unconnected cause it always cause problems and the DJI OPTO 30A that I'm using doesn't have a BEC anyway.
  • The USB port can be programmed for any USB device application
  • microSD card slot via SPI
  • Indicators: 1 led power indicator, 1 small green led for status or anything else and 4 high power sideleds for beacon and directional ligths (maybe white leds would be nice)
  • Sensors:  The is a I2C network on the board with: MPU6050 Accelerometer and gyroscope with data fusion integrated, HMC5883 magnetometer (slave to the MPU but could be bypassed), BMP085 Barometer (can be used as an altimeter), LM60 temperature sensor, 128KB EEPROM for configuration saving, 
  • Xbee Radio: is it possible to fit an Xbee standard on PRO
  • Programming: could be made via JTAG or with the built in serial bootloader via Radio (slower but very useful)
  • SPI, I2C and UART headers for external devices, sensors, etc.
  • Real time clock with calendar (implemented by the LPC1769 but there is an external crystal for clocking)

About the firmware:

I'm currently working on my thesis firmware and the simulator (on MATLAB). Cause it is not ready at all I would prefer not to publish it yet. But, I wrote a small tester firmware for all the devices that will give you an example on how to use  them, and also have a very small "template" for starting. The board is perfectly capable of running FreeRTOS (which I'm using extensively) and the IDE I'm using is the LPCXpresso Free IDE (128KB flash limit now).

Some videos:

First flight: https://www.youtube.com/watch?v=YBPmafMSqKM it is a little buggy, it was my first ever flight of a RC thing (be gently :) ) and was only fliying with Gyros so no attitude controlling was made.

MPU Motion fusion testing: https://www.youtube.com/watch?v=vLnvzxnk2og

And some pictures:

http://www.flickr.com/photos/akharsa/sets/72157632740777181/

Ground station:

My ground station is now a xbee via USB and a PS3 joystick via bluetooth. The GS is not something I'm proud of it yet but is getting into shape slowly.

My idea now is to publish the schematics of the board open to everyone, and even the PCB files. Maybe later the firmware when I have a stable version (of course the small templates will be on github soon). I'm not wondering to be the responsible for quadrotors breaking (I broke my yesterday . I'm also thinking in selling this board already assembled (in china where I manufactured the PCBs) to easy the people acces to this board. I'm not sure if it is a great idea yet.

Currently the board is not intended for people looking for a Ready To Flight option, exactly the opposite  But I'm sure that there are people out there that make use of this kind of stuff (Arduino for example :D) and I would like to share my work with them as they do with me.

Thank you!!

Alan

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Developer

Dropping a Rover from a HexaCopter

For those interested in using their multicopters to carry heavy objects you might be interested in the test that I performed today with Assistant Professor Nagatani-san of Tohoku university in Japan and Izu-san of EnRoute (a company that specialises mostly in Radio Controlled vehicles here in Japan and China).

The goal for later this year is to carry a rover to the top of Mt Asama (a volcano that errupts from time to time) and drop it in mostly as a proof of concept that it can be done.

Today was our first attempt at dropping one of the university's semi-autonomous rovers (2.5kg) from an ArduCopter equipped Zion Pro hexacopter (4.0kg not including the rover).

During the first try the copter was under manual control (stabilize mode) and the servo to drop the rover was activated by the tx/rx's channel 8 switch.  I was the pilot and although we were all fully expecting the copter to climb I was still surprised by the speed of the leap into the air and I couldn't keep the throttle low enough without cutting the engines completely.  You can see the disasterous result 44 seconds in.

After lunch and fixing the hexa the 2nd (1:02) and 3rd tests (1:11) went much better with lower weights (300g and 1kg) and this time using Alt-Hold.

The final test (1:24) was back again with the rover but this time using alt-hold and you can see how much better the new 2.9.1 Alt-Hold is than a human pilot (or at least this human pilot!) with the copter only climbing about 10cm or so.

So the moral of the story is sometimes it's best to trust the autopilot.

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3D Robotics

The Economist on thermal-seeking drones

20130209_stp510_168.jpg?width=168

From The Economist:

ALTHOUGH undeniably graceful, gliding has until now been suitable only for pleasure flights. But this is changing, as researchers exploit wind power to enhance the capabilities of unmanned aircraft, especially small drones. Soon, these gliders will be able to stay aloft for weeks. They will thus be able to act as communication relays, keep a persistent eye on the ground below and even track marine animals thousands of kilometres across the ocean.

One such glider, the hand-launched Tactical Long Endurance Unmanned Aerial System (TALEUAS) is being developed at the Unites States’ Naval Postgraduate School in Monterey, California. It needs an electric propeller to get airborne, but give it a few minutes to reach a reasonable altitude and TALEUAS can fly all day just by riding rising currents of warm air called thermals.

When TALEUAS encounters a thermal it senses the lift and spirals around to take advantage of it. Vultures and eagles use the same technique, and Kevin Jones, who is in charge of the project, says he has often found TALEUAS sharing the air with these raptors. On some occasions, indeed, the birds found that the thermals they were attempting to join it in were too weak for their weight, as the rone is more efficient than they are at gliding.

TALEUAS’s endurance is limited only by the power requirements of its electronics and payload, for at the moment these are battery powered. Dr Jones and his team are, however, covering the craft’s wings with solar cells that will generate power during the day, and are replacing its lithium-polymer battery with a lithium-ion one capable of storing enough energy to last the night. That done, TALEUAS will be able to stay aloft indefinitely.

TALEUAS does, however, depend on chance to locate useful thermals in the first place. Roke Manor Systems, a British firm, hopes to eliminate that element of chance by allowing drones actively to seek out rising air in places where the hunt is most likely to be propitious. As well as thermals, Mike Hook, the project’s leader, and his team are looking at orographic lift, produced by wind blowing over a ridge, and lee waves caused by wind striking mountains. Their software combines several approaches to the search for rising air. It analyses the local landscape for large flat areas that are likely to produce thermals, and for ridges that might generate orographic lift. It also employs cameras to spot cumulus clouds formed by rapidly rising hot air. Such software replicates the behaviour of a skilled sailplane pilot—or a vulture—in knowing where to find rising air and where avoid downdraughts.

Perhaps the most ambitious scheme for a robot glider, however, is the artificial albatross proposed by Philip Richardson of the Woods Hole Oceanographic Institution, in Massachusetts. Like its natural counterpart, this artificial bird harnesses wind shear—the difference in wind speed at different heights—in a technique called dynamic soaring.

The air is quite still near the surface of the sea even when it is blowing powerfully just a few metres above, so an albatross can rise up and face into the wind, gaining height like a kite in a breeze, then turn to glide down in any direction. By repeating this manoeuvre it can fly thousands of kilometres without flapping its wings, and by tacking it can travel anywhere, regardless of the wind direction, with an average speed six times that of the wind. Dr Richardson thinks he can replicate this with his robot bird. If he does, he will surely break all records for the time a heavier-than-air artefact has stayed airborne.

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This is in continuation to my earlier blog post on Hardware In Loop Simulation For Co-operative Missions Using ArdupilotMega

This video was recorded through live video telemetry from the 'Follower' aircraft running custom code(attached below) on APM autopilot board. The 'Follower' aircraft receives waypoint information from a 'Leader' aircraft also running on APM autopilot board and thus follows the leader aircraft autonomously through the air.

The video shows the airframe of the follower on which the camera was mounted. We were hoping to catch the 'Leader' aircraft on the camera flying ahead of this follower, but poor video signal quality left us wanting more. Although you can occasionally see the leader in the video (at 3:30), its no more than a black spot in the air. Next time we'll probably use something like FlyCamOne for onboard recording or a better video telemetry kit.  

Autopilot Used(Both Leader and Follower) : APM 2.5 (Latest)

No hardware changes required except for soldering burg-strips on UART2 of APM2.5 board. UART2(Serial3) is used for all telemetry.

Communication modules used : Xbee Pro S1 in API (mode 1) on all Aircrafts(UART2) and Groundstation Laptop

Aircraft GCS communication : MAVlink v1.0  *Embedded in Xbee API header and Footer.

ie (API Header)[All MAVlink Packets](API Footer)

GCS used : MissionPlanner, Qgroundcontrol GCS coupled with MAVproxy.

MAVproxy is used to collect data from groundstation Xbee and Add/Strip API headers as and when required to send clean MAVlink packets to qGCS and MissionPlanner through UDP connection on separate ports.

Inter Aircraft communication : In Xbee API protocol (Not MAVlink)

No. of MAVs in the cooperative mission simulated : Upto 3 till now, can be easily extended to more.

Cooperative missions flight tested : Leader follower for 2 MAVs.

The sketchbook containing the firmware for the above cooperative mission is attached.

Flight Tested Leader-Follower Sketchbook. I'll write a small readme on how to set this system up and get it going soon, it's straight forward really.

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Micro Siri Heli Part 2 - Click here to View

Home Page - Drone Cafe Video Podcast to check out Part 1

Drone Cafe Youtube

***If anyone has any knowledge in voice control, programming, Siri code, or anything useful to this project please help contribute.  You can do that by giving me all the information that you think I would find useful in completing my goals for this project.***

Useful Links to this Project:

Siri Controlled Arduino using Ruby

Features:

  • Electric Powered
  • Built In GYRO
  • 3.5CH Transmitter
  • Coaxial Main Rotor
  • Single Rear Rotor
  • Metal Construction

 

Voice Commands:

  • Take Off (Finished)
  • Fly Up (Still working On)
  • Fly Down (Almost Finished)
  • Backward (Still working On)
  • Forward (Almost Finished)
  • Turn Left (Still working On)
  • Turn Right (Still working On)
  • Turn Around (Still working On)
  • Spiral Up (Still working On)
  • Drop Down (Still working On)
  • Dance (Still working On)
  • Three Point Maneuver (Still working On)
  • Circle Strafe (Still working On)
  • Orbit (Still working On)
  • Drift Maneuver (Still working On)
  • Double Dash (Still working On)
  • Take Photo (Possibility)
  • Start Video (Possibility)
  • Stop Video (Possibility)

Specifications:

  • Length: 8 Inches
  • Wingspan: 8 Inches
  • Height: 4 Inches
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How to learn ArduPilot Settings

The best way to learn how to change the PID and other settings in ArduPilot is with a simulator.  I've made a quick video to show how to setup Ardupilot with Mission Planner and X-Plane.  When you get this working you can change the PID and other setting real time and learn what they do.  Then change plans in the simulator and setup ArduPilot for that plane.  When your get ArduPilot fiying a 767, send me your .params file.  ENJOY

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3689502495?profile=original

Thanks to Pteryx for this great data set! In order to generate a geo-referenced NDVI / EVI / EVI2 Vegetation Index we need to fly the area of interest (AOI) with a visible (RGB) and full spectrum (RGB+NIR) camera. Once the RGB and RGB+NIR images are processed inside DroneMapper we have two orthomosaic results from which we can generate a pure NIR ortho. To do this, we use GDAL and the following command: 

/usr/local/bin/gdal_calc.py -A VIS.tif -B NIRVIS.tif --outfile=nir.tif --calc="(A - B)"

Now that we have created our pure NIR orthomosaic we can use this to generate NDVI or other calculations using OTB in an automated fashion.
 

/usr/local/bin/otbcli_BandMath -il NIR.tif VIS.tif  -out ndvi.tif -exp "ndvi(im2b1, im1b1)"

In order to process the orthomosaic tif files, they need to be the exact same size and pixel resolution. OTB also has many other useful commands for remote sensing work. The original flight and area of interest is 1.0 km sq @ 10 cm GSD. 

Thanks -- JP @ DroneMapper

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3689502805?profile=originalTaking Autism To The Sky - We're looking for your support on KickStarter as kids with autism get a new perspective of the world - from the air - by building/flying a hexarotor and producing a video of their journey. 

 We've seen/participated in lots of discussion on DIY Drones about the non-military, social and environmental uses of the technology that we all are interested in.  I've been one of those heavily engaged in that discussion.  To that end, I'm excited to announce my KickStarter project that gives a group of kids on the autism spectrum a chance to build a hexarotor, learn to fly it and capture footage of both the process and the flight.  Go check it out.

 

The team will be comprised of a small group of kids on the autism spectrum and a few adults including me.  The kids will build a hexarotor from a kit that includes GPS, high definition video, and flight planning software. After building the hexarotor and learning to fly it, they will plan a mission, fly it, and then produce a video both of their time building and learning to fly as well as the flight itself.  The video will be provided to their school district to put on their web site demonstrating the team's skills.  We can post it here too!  We've got a well thought out budget and a game plan.

 

I wanted to thank a handful of DIY Drone members (listed below) who were kind enough to offer some of their flight footage for use in the KickStarter video.  I did use clips from a few of you guys.  Thanks for the help!

  1. David Anders
  2. Stephen Dade
  3. Kevin Bouchard
  4. RCrecon.be
  5. u4eake
  6. John Arne Birkeland
  7. Gerard Toonstra

 

Check out the project on KickStarter here.  Thanks in advance for any support you're able to offer; a Tweet, a link posted on social media, or a donation to help fund the project!

 

Cheers,

 

Paul

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