Jesus A's Posts (3)

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Usage of small dimensions RPAS ( drones ) has a real and practical benefit on forest, environment and agriculture management. Drones can obtain Digital Surface Models and pseudo-NDVI orthomosaics that can be manipulated by Geographic Information Systems (hereinafter GIS) allowing professional and rigorous studies along with technically supported decisions.

We provide here an example of woody crop inventory done with our drones and GIS (QGIS) Software. It can be noted how powerful this information can be to properly manage and take decisions on precision agriculture and forest plantations.

In the following example droning used one of our drones (specifically the DE820) and a NDVI camera to survey the whole field. We did it in one flight at height of 100m above ground. Flight took 10 minutes.

The field was mainly populated by olive trees in the south of Spain.

Once on the ground, we were able to generate the Orthomosaic and both DTM (Digital Terrain Model) and DSM (Digital Surface Model). By using these three sources of information and the raster and vector calculator on the GIS, we could detect and classify every olive tree as an independent entity.

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Having every olive tree entity located in the GIS database, a lot of valuable information can be extracted:

  • GPS Location
  • Height
  • Estimated volume
  • Perimeter
  • NDVI index
  • Surface area
  • etc

Woody crop was identified from surface and other vegetation by means of geographical calculations taking into account a series of parameters like shape, height, area and elevation gradient. At the same time NDVIb color disambiguation was applied to better refine the tree selection.

In this example we were able to differentiate every olive tree from the rest of the terrain and other vegetation present in the study zone.

 

GIS and drone technology is a game changer in Precision Agriculture and Environment management. This information provides an efficient, massive and rigorous way to manage field crops, forests, and any other geographic inventory.

Data obtained in this way can create massive lists/catalogs of fine geolocated entities allowing categorization, historical comparisons, etc.

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The fact that every olive tree has been categorized, geolocated and found their characteristics is of a great importance now and even more in the future. Almost every new technology related to automatic crop harvest or automatic  fertilizer application will have to be supported by these data.

Moreover, historical data across the years can give precious information about growth patterns and diseases that can me data crossed against production rates per tree etc.

Full post here.

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Hi all,

We would like to share with you our company "droning" (www.droning.es) devoted to create and operate professional UAVs. 

Our team has been around diydrones for some years now and we all share our passion for drones and APM.

Some of us started with APM 1.0 or with ArduIMU.

We have focused our efforts on creating quality turn key products that incorporate all our experience in the Multirotor/Planes operation. We have been providing survey services for more than a year now and we have some ideas about how a good platform should look alike:

  • Robust and easy to operate
  • Long flight time (obvious, I know)
  • Easy (and quick) to fold and transport
  • Integrated electronics and modular design
  • No cables or protruding parts -> fairing 

Multirotor DE820

With these requirements in mind we started to design a Multirotor (DE820) that could be able to be configured both in Quad and Octo coaxial mode. This way it could be used for Endurance missions on surveys but also for filming and high payload missions.

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We ended by choosing umbrella folding arm design and single-point fixed landing gears as they offer a great stability in rough terrain where it is supposed to operate.

In the Quad version we have:

  • 18 to 20" T-Motor carbon props
  • Tattu 22Ah 6S
  • Pixhawk 
  • more than 30 minutes of operational flight

In the Octo coaxial we have

  • 16" t-Motor carbon prop
  • Tattu 22Ah 6S
  • Pixhawk
  • 25 minutes of operational flight

We have created custom PCB to integrate ESC and basic signal routing so we simplify the manufacturing process.

In the next revision we are using Dropix v2 as it will allow us to mount it in a PCB socket and simplify it even more.

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The DE820 can be configured with quick release payload holder, allowomg to reconfigure it quickly by swaping assembled gimbals with cameras or even connecting an EPM gripper without cabling or screws intervention.

You can find more pictures, information and videos on the web.

TA2000 Plane

Even if the DE820 is our more loved product we do have a Fixed Wing based upon the Talon airframe. We called itTA2000 and it has passed thru a customization process quite intensive.

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We added a front motor mount as we think it flies much better and allow for easier hand launch.

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With its current configuration it weights 2kg with camera on board and batteries. Regarding flight time it can go up to 1 hour at 50km/h.

We are working in extending the range close to 2 hours by using Li-Ion mixed battery.

Hope you like it.

Jesus, Anderl

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Hi all,

Some months ago I decided what new camera I will use for my big Hexa. Many many people are using Sony NEX5 cameras for aerial photography. However they a expensive and you need IR Trigger electronics.

I took a look at Samsung NX line and found Jeff Taylor (thanks for the inspiring post) post about triggering them with a simple resistor (not said in that post but I guess you need relays anyway). So I went for it.

I bought a Samsung NX2000 which I must say takes wonderful photos and videos. But Jeff's trigger mechanism did not work in these particular camera. After some trial-error I found that the camera "wants" you to always "focus" before trigger the shutter! No matter the camera setting,  believe me!

So what I have. I have an Autopilot that (in relay mode) outputs 5V(APM) or 3.3V(Pixhawk) for a given period of time (shutter time).

With that signal I have to use relays to create two shorts in NX2000 USB pins. One short between FOCUS pin and GND pin and another short between SHUTTER pin and GND pin.

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Samsung NX2000 is quite restrictive in how to short those pins. After more trial - error I discovered the following:

  • SHUTTER and FOCUS pins cannot be permanently connected one each other. Otherwise, no shutter
  • FOCUS has to be shorted to GND some "time" before SHUTTER does. If you short both of them at the same time to GND, you will have a random behaviour. Sometimes it works and sometimes not. This was really annoying as it prevent you to use a double relay to short both pins at the same time

So I decided to built a small circuit to trigger the camera by shorting FOCUS to GND and then (anytime after) SHUTTER to GND

I used what I found at my local electronics store. It maybe done differently!

The circuit for triggering NX2000 receives 5V Vcc, 5V signal (will trigger relays, etc) and GND either from APM or from a 5Vto3.3v level shifter if we use Pixhawk.

Bill of materials:

 - 1x NE555

 - 1x 1uF capacitor

 - 1x 18k resistor

 - 1x 10nF capacitor

 - 2x double micro relay

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The mechanism is as follows. Once the signal goes high (5V), it drives the relay ON. This relay has two lines, the first shorts FOCUS and GND. The second allows 5V vcc to go and feed the NE555 timer.

So we have already provided focus to the camera. Now we only have to trigger the shutter.The amount of time that the NE555 takes to boot up is going to be our FOCUS-SHUTTER delay. It is normally 100ns.

Once the NE555 boot up it always sees a short in it input pin. Therefore it puts its output high what drives the second relay.

Once the second relay is activated, a short is created between SHUTTER and GND.

On this point you should have a nice picture taken in the NX2000!!

One thing left to say. If you come from Pixhwak world you need to convert 3.3v signal to 5V.

I used Marco's circuit in this post

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As you can see all three boards/circuits are connectable/stackable one each other.

Here you can see the full picture:

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The FOCUS-SHUTTER delay may have been done with a RC net but I chose NE555 in case a needed to control delay accurately. However I would have needed another NE555....... 

For Pixhawk connection I connected it to OUT 5 (as 1 to 4 are configured PWM) and Relay mode. 

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Some pictures of the process and final result

Bench test:

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USB Connector

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Everything in a prototype pcb

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Already mounted on gimbal with shrinking tube

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