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I have started to build an APM controlled sail boat. 

The hull

The hull is based on a IOM boat called Goth (Free plans here). It is built with balsa strips and then glassed on both the inside and outside. Keel blade and rudder are made with balsa cores and a carbon fiber shell. The bulb is 3.5 kg lead. It is designed to weight 4.2 kg when finished. 

The wind vane

The wind vane is built around the magnetic rotation sensor chip as5045. With a magnet placed just above the sensor it can detect the absolute angle of the magnet. The magnet can be seen below the ball bearing in the image below. The sensor chip measures just 5x5 mm and is embedded in epoxy. The wind vane and the sensor is placed in the tube and voila. A wind direction sensor with almost no friction and a total weight of less than 10 g. Total length is 10 cm.

I still need to figure  out where to put the wind sensor. Since i have a rotating mast it is not a good idea to put it there unless i fit another rotation sensor on the mast. 

The wind vane is quite sensitive. It works at walking pace so hopefully it will work on the boat.

Mast

The mast and boom is made of a fiber glass fishing pole. the sail is made drawing film. It is made as an IOM sail and the sail area is similar to an IOM size two sail (main plus jib).

I have not decided how to control the sail. I can use a traditional sail servo or rotate the mast with an arrangement under deck. 

Control

The boat will be controlled using the APM hardware and sensor libraries. 

The plan is to take it step by step:

1. Manual RC-control
2. Manual RC-steering with automatic sail control
3. Heading and/or Wind angle hold. 
4. ...

All comments and ideas are welcome!

/Magnus

Hello All,

We have just interviewed Wayne Garris creator of the Techpod and I have made episode one of building the skywalker X8

So enjoy.

Moscow State University.
Hardware stability test.
Video "as is".Without any postprocessing (no deshaker, no color correction, etc.)
Camera: Canon 5D Mark III
Lens: Canon EF 24 mm F/2.8 IS USM

So I managed to interface my Leap Controller to the Tau Labs GCS and use it to control my Sparky based quadcopter by waving my hand around the sensor.  It's a pretty weird way to fly but became somewhat natural quite quickly.

Here is a video of it working, and if you stay to the end the first five attempts which were not quite as elegant:

Controlling quad with a wave of the hand from James Cotton on Vimeo.

A full write up can be found here http://buildandcrash.blogspot.com/2013/08/controlling-quad-with-wave-of-your-hand.html

From The Verge (with suitable skepticism)

German non-profit group Definetz wants to make defibrillators readily available across its country so that any time someone has a heart attack, the life saving devices are within arms reach. And it's looking to drones to help it bring its vision to fruition. On Friday, the group announced the Defikopter, a concept device it designed with drone-maker Height Tech to fly defibrillators to emergency responders or the public by way of a GPS-enabled smartphone app.

Definetz says the Defikopter, which was developed over the last three months, can travel within a radius of 10 kilometers (about six miles), and fly at a speed of 70 kilometers per hour (about 43 miles per hour). While Definetz and Height Tech have announced their collaborative design, neither organization said if or when the Defikopter would be made available for sale, or when and if the corresponding smartphone app would be released to the public.

There are, of course, a few drawbacks to the drone concept. If built, the drone hardware would sell for about $26,000, according to the Mittelbayerische news site. Additionally, if the Defikopter and its app are made available, the Defikopter can only be hailed by someone who is with a heart attack victim and already has the app downloaded downloaded on their phone. The drone also can't run without supervision — the Die Glocke newspaper reports that German law requires that unmanned flying vehicles can only be flown if monitored by a human being. These limitations and restrictions could mean the Defikopter concept never makes it off the ground.

This is my new design composite 2m Delta Flying wing

I wrote a few weeks ago about testing out a Schott BG3 filter on an SX260 for detecting vegetation stress remotely. That post and the results of this conversion are posted here. We’re now selling both those filters individually as well as pre-modified cameras at Event 38 for those interested in testing them out, but be aware before you grab one that the processes related to setting the right white balance, calibrating imagery to compare results from different pictures and even post-processing are not yet finished. We’ll be working on improving these but I wanted to make available what we have right away because there are some people interested in getting started right away. The process shown below will work just as well for any other filter you get anywhere else.

Before you start, it’s good to have a good selection of screw drivers, a brush, an air puffer, a marker and tweezers close by.

To start, remove the back section of the camera by unscrewing 1 bottom, 2 right and 2 left side screws.

Once the back is loose, pull it off gently and remove the flex cable by sliding it upwards out of the socket.

Next, remove the bracket holding the right side of the LCD in place by removing the single screw at the top.

Now the LCD is loose. Slide it a bit to the right so it clears the lip on its left side and then pull it up on the left side. There is a flex cable in the upper right corner that can’t be pulled too hard or it will come out. Accessing it to replace it is very laborious so be careful not to put too much stress on that cable! I use masking tape to keep the LCD up and out of the way while working beneath it.

We’ll be unscrewing the 3 screws on the back of the sensor in a moment but first we need to remove the glue holding the sensor plate down. The glue is pretty tough, so I use a really sharp exacto knife to scrape it away bit by bit. Quick, light cuts work better and are less likely to damage something else than pushing hard so be gentle. Use a brush or air puffer periodically to remove the debris.

Once the glue is out of the way, mark each screw’s position using a marker before unscrewing them. Make sure to set the screws aside in a way that you know which position to return it to later.

Take the screws out and gently remove the sensor plate. Clean the area again to remove any dirt/dust that has fallen in. The reddish piece of glass in the center is the IR-block filter that normally keeps out all infrared light. Remove the rubber placeholder holding the filter in place.

Remove the filter glass carefully using tweezers and set it somewhere safe in case you need to put it back in later.

Clean the entire area again.

Now carefully drop in your filter glass.

Replace the rubber placeholder and then the sensor plate on top.

Replace the screws in the right order and screw them in until the marks match up as closely as possible.

Close the camera back up by replacing all the screws and brackets and don’t forget the flex cable on the back of the case. Finally you’ll want to check and make sure there’s no dust on the sensor or inside of the lens. Put the camera in Aperture priority mode and open up the aperture as wide as possible. Zoom the lens in all the way and focus the camera on something far away by half-pressing the shutter button. Now aim the camera at a clear sky or a white piece of paper and make sure it fills the entire screen. Take that picture and then look at it to make sure there are no black spots, below is the image as it came out of the camera used in this tutorial.

If your image came out clean too then you’re all set! If you’re using a Schott BG3 filter, a quick and easy way to start processing images for vegetation stress is to set the camera’s white balance to the cloudy preset. This will allow you to process a vegetation index that represents vegetative cover and growth, although the results don’t yet cover the full scale of values as they would using a traditional multispectral camera.

Treehuggerreports on this cool research from a group at the Vienna University of Technology:

The team's quadcopter, which is said to have been built with components costing less than one thousand euros, uses the smartphone's camera to provide visual input to the processor. A custom smartphone app provides the code for navigation and control. and rotor speed is regulated by a micro-controller for optimum stability while flying.

The model created for this project relies solely on visual data for navigation, not GPS, and is built specifically for indoor environments and small spaces, where it has been shown to be able to create a virtual map of its environment and then navigate on its own.

"To test the quadcopters navigational capabilities, the team attached visual codes to the floor, similar to QR-codes. Hovering above these codes, the quadcopter recognizes them, obtains information and creates a map of its environment. Once it has created a virtual map of the codes on the floor, it can head for a specific known location or go on exploring areas it has not yet checked out." - TU Vienna

While this indoor version of the autonomous quadcopter may be useful for first responders or disaster response, to survey the inside of a building before entering it, it's quite possible that a variation of this design could be built for use out in the environment, as a monitoring or patrolling device for wildlife or forests.

Almost finished the Octo build and thought I would take some shots at dusk.

Quite pleased with how these have come out, the LEDs really set the Octo off nicely.

The first teaser video of Iris, our totally ready-to-fly quadcopter UAV with the new next-gen autopilot. Developer pre-ordering is now open here, for shipment on Sept 16th  

I thought I'd share the following video with you.  After spending several months trying to replicate the rock solid loiter videos, I've finally suceeded - and the only thing that I needed to do (other than vibration dampening) was to raise the GPS several inches above the top plate and keep the wires away from interference sources.  The HDOP has dropped from 1.9-5 to 1.3-1.6.

Additionally, I've add LED strips to the arms which are controlled by the ArduCopter board using some custom code. When armed it oscillates around like shown.  When disarmed, the arms flash when a GPS lock is absent, and are solid when there is a GPS lock.  Giving a clear indication when its safe to fly.

You can find the code for my leds.pde file at:

https://github.com/drgowen/ardupilot/commit/d5df7fce01731d5b27c3b1e83e2d09f1e719fb64#ArduCopter/leds.pde

It's fairly easy to modify, the update_copter_leds() function gets called at regular intervals, you just have to decide what to do - in my case I check the armed status and GPS state.

Here are some close-ups of the arms and legs. They are made from DuPont Zytel®, very strong and resilient in a wide range of temperatures.

Guillermo had some break force testing done, the results were impressive:

In the center it takes 204 lb (92.5 kg),  and at the tip  772 lb  (350 kg).

Sliding dovetail and set-screw retains the legs, allowing for easy replacement if needed. Picatinny rail mounting system integrated into the bottom of the arms provides endless mounting options for accessories. 

Motor wires are protected, but not buried. Quick release clips keep things tidy.

A few months back there was a story that PETA had acquired some drones and were planning on spying on farmers.  Many users of this technology might have been concerned that this questionable use might cause farmers to "shoot down" innocent drones operating near their properties.

Instead, farmers have embraced this technology and produced their own drone video.

DIY multicopter lighting project

I have been working on a lighting setup for my quadcopter that is custom and can perform many different lighting sequences. I also required it to be powered straight from a 3S lipo balance plug, controlled remotely using the aux channel on my transmitter and have a FTDI connector to update the arduino code without removing the microcontroller.

For anyone interested in making their own I hope this schematic, code, PCB design and photos will help out and save you hours of work.

At first I tested the code and design using an Arduino UNO and a breadboard, then when I was happy with how that performed I designed the schematic and PCB to use the ATmega328P microcontroller standalone to reduce the weight and size. One important thing to note is that I wanted to eliminate the external clock and use the 8 MHz internal clock, instructions on how to do that are here.

Build of materials:

• ATmega328P Microcontroller
• ULN2003AN Transistor package
• LM7805 Voltage Regulator
• 0.33uf Capacitor
• 0.1uf Capacitors (x5)
• 1k Resistor
• 10K Resistor
• Tact Switch
• 3S 4Pin JST-XH Socket
• Male header pins (optional)

Files:

All files including the arduino code, eagle schematic and PCB board files related to this project can be found on github. If you have any suggestions or improvements please submit a pull request and I will add it to the code.

https://github.com/drewsdesign/rclights

Video of it attached to my quad and the different light sequences is above

Schematic

First prototype for testing the circut and arduino code.

Second prototype. This was going to be the final but it was too bulky and my wiring was pretty dodgy.

My attempts at etching a PCB. This was my first time doing this so I made a few mistakes.

The final board. I made the mistake of spraying some pcb coating before soldering which made it difficult, but it works and I didn't feel like spending time on another one.

Link to my tumblr blog for more info

As a follow-up to the rover drops #1 and #2 I spent a day with Assistant Professor Nagatani-san of Tohoku university in Japan (and his students) and Izu-san of EnRoute (a company that specialises in Industrial use multicopters and hobby use RC vehicles here in Japan and China) at Karuizawa's Mt Asama attempting to autonomously drop a 2.5kg rover from a large (4kg+) EnRoute "ZionPro" hexacopter.

The flight was completely autonomous including activating the servo release which held the rover to the hexacopter (we used the camera shutter release).  After being released the rover was "lowered" on a 30m wire wound around a brushless motor which was meant to slow it's descent (with mixed results).  If you've never heard of this mechanism before, it seems if you connect the bullet connectors of a brushless motor together it resists being turned.  If you attach a resistor between the bullet connectors it will resist less strongly.  In this way we could somewhat adjust the speed at which the rover descended at.

A couple of things that we learned from this test in case you try something similar:

• the altitude reported by a Ublox GPS (i.e. APM/PX4) vs a hand held GPS can vary by 10m.
• the altitude reported in google maps (and thus the mission planner) can vary by 20m from reality because they only provide the average altitude for the area.  I'm not sure how big that area is but we found that google maps altitudes could be high or low from reality depending upon where you were on the slope.
• trying to drop from a wire is tough!  we need a more reliable system for the next test.  Maybe use a range finder to get the copter closer to the surface without hitting it or perhaps measure the motor output to determine when the dangling rover has reached the ground.
• the hexacopter and battery were more than sufficient to carry the rover the 600m covered in this test.  At least twice that distance would have been possible.
• AC3.0.1 is very capable of the accuracy required for this mission.  It was a thing of beauty.

There will be one more attempt within the next 2 months which should be pretty much the same except the distance will be further and the dropping mechanism will be improved!

Thanks and all comments, input welcome!

Goosebuster, an offshoot of Aerial Perspective photography, is patrolling the city park with a six-propeller chopper, outfitted with plenty of battery power and an speaker blasting predator sounds.

Steve Wambolt was originally trying to sell the city his photography services but Monette suggested using the helicopters to scare geese instead. Wambolt received the necessary wildlife and operating permits and started hitting the beach last month.

Full article here:

http://www.ottawasun.com/2013/08/20/goosebuster-hobby-copter-chases-nuisance-birds-off-ottawa-beach

Hi,

Almost 1 year ago I started a topic on the diydrons forum in wich I asked on how much efficiency loss I will have on converting my quad to an X8. Almost no reaction to my question. Nobody could give some figures wich I could use for my calculations. The only helpfull answer I got was from somebody who said that the efficiency loss depends on prop size and distance between the props.

Time has past, other projects are closed so I'm starting with the build of a Y6 multirotor. And the first thing before building the frame is a thrust test of 2 motors in sequence. Result is a 10% efficiency loss. See full graph and info on my blog at http://wipo-y6copter.blogspot.be/

This figurs can by handy for everyone who is building Y6/X8 copters. Currently I'm building the frame, but I will try to post more efficiency loss tests for other prop sizes asap.

For my own rover, Data Bus, I've been working on a board that converts Sharp range sensors to I2C.

I ran out of analog ports and had to prototype an I2C solution for my obstacle detection. I have this problem on all my robots. Pokey has too few analog ports. And I want to run a few of these on my RPi tele-rover.

They'll work with any Sharp ranger. For that matter, with any analog sensor (ideally at 3.3V or 5V). I plan to test a Maxbotix Sonar module soon.

Up to 27 of these on an I2C bus without re-programming the base address.

The firmware's oversampling, decimation and low pass filtering increases resolution and lowers noise floor. The analog anti-alias filter helps too. Performance is really good. Here's a pseudo-theremin demo:

They're running ATtiny44As. 6-pin AVRISP header doubles as I2C interface -- SPI and Serial on the newer revision is possible; I break out an ~SS pin. I also break out 2 GPIOs for the heck of it. I'm testing out SOIC and QFN versions.

If there's anyone who's building a project using analog rangers (Sonar, Sharp, other) and wants to try these let me know.

I have example code for Arduino, mbed, Raspberry Pi, and Propeller so far.

From the University of Texas in Austin, Texas, USA    

# note that there is a glimpse of architectural art piece in this video by James Turrell, Skyspace, 2013,  courtesy of Landmarks
I originally solicited other construction company users as to their ideas about using drones in the industry and to heat there experiences. This might not be the right venue for that, instead I got responses that mostly was about legalities and professionalism etc.

I just want to mention that I had knowledge and consent from the owner to publish this video, which meets the "non Applicability Sec 423.002 (6) which says it is lawful to capture images with the consent of the owner.  I have full consent from the owner, the Texas State University. And, I am just a employee of a construction company with a simple qaud copter and by no means a professional, so the video is not done to a professional standard. I found it to be quite a challenge to fly FPV in a crowded airspace without losing LOS and still trying to "get the shot"  with FPV sometimes you have to look where you are flying, and not at the subject that you are trying to film. Perhaps that is why there are often many cuts in some pro videos.
     

     The Quad Copter I used on these video's is a DJI Flamewheel,450 with a NAZA-M controller with the GPS.  I use a EZ-OSD for basic flight info, and I use a Sony CCD wide FOV camera for FPV, transmitted to the ground with a Immersion 600 MW Video Xmitter.

      It is using a 5500 MAH 30C LIPO, and I have the FPV camera rigged to a servo so I can "look" down. I receive the video both on a Fatshark video google and also an immersion DUO receiver that is attached to a 9" LCD monitor that is handheld by my spotter. There is also a Japan FPV DVR for recording the OSD and Flying camera imagery.

     All this is set up to be powered by a 3s LIP0. More info on the video ground station is here   

     The Camera doing the video is a GoPro Hero 3 Black Edition and is not using any gimble for stabilization. It is just attached to the frame firmly with without vibration damping. It seems pretty free of jitter, but of course it doesn't track level. I plan to add a gimbal soon. I have a nice brushless gimbal, but it looks like it might fit better on my Ardu Copter.

    So far the owners of the projects I've heard from really like to get the videos and stills because it gives them a much more complete picture than they get just visiting the construction site. Also, its just cool. I haven't found anyone who has prohibited using drones on the site, however as the drone operator, I focus a high level of attention to details in checking out the equipment before and after flights and and awareness of bystanders and subject the entire  process to a critical review of the flight plan, equipment condition and all safety considerations.   I think we have to be our own inspectors and make our own safety rules, we absolutely don't want an accident to mar our record of being a responsible group that can bring value to the construction industry.

note#   comments are turned off, but you can send them to my profile..  Thanks!

   Here are a couple of my flyovers...

And check this story on Constructech.com  

    http://constructech.com/news/articles/article.aspx?article_id=9763&SECTION=1

RE
------------

Since I first posted here about this competition last October, we've been pretty busy.  NASA selected Development Projects Inc. (DPI) of Dayton, OH to be our partner and run the contest.  We've selected Camp Atterbury, Indiana (in the restricted airspace around Himsel Army Air Field) to be the location, and we're working on putting everything in place so we can stage the competition in mid-May, 2014.

We've made quite a few changes based upon feedback we received from everyone and assembled a new set of Draft Rules and a draft Team Agreement for you to look over and give us your feedback. We're trying to cast a wide net and run a contest that will be open and fair to any group that plans to work professionally with unmanned aircraft in the U.S. National Airspace System.

A big part of our preparation is putting together a "Traffic Squadron" of unmanned aircraft that can create the air traffic for the competition. We're using some large scale RC planes and outfitting them with Ardupilots and ADS-B transceivers.

DPI has has put up an initial web site and they have posted the new drafts of the rules and the team agreement on this page:

    http://www.uasaoc.org/rulesreview.html

You can also sign up for the competition mailing list on this page to be informed of future developments:

    http://www.uasaoc.org/contactus.html

I look forward to your comments!

Garry