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Hi everyone,

For years now we use model aircrafts as a hobby or job, and for many years  as aerial platforms for aerial photography and mapping. So after many discussions here and reading, I will begin here an UAV application that I think and prepare from student and I hope that now I have the background to make it happen. The reason I post the project here is because I learned all about model aircraft from aeromodelling.gr and everything I know for autopilots from diydrones.com

I began my first efforts for knowledge and hobby with the famous Telemachus (similar to telemasters).  The Telemasters are well known to most of you and they have been used as such platforms, although satisfactory results have pluses and minuses that we saw in corresponding topics. So after studying, planning and design of many commercial and non-commercial UAV’s, i resulted in the formation of one new platform that meets ALL of my conditions: 

• Be able to lift all the flight equipment, control, transmission, cartography, FPV
• Have a decent flight time (~ 20-25 minutes)
• Have a great airspeed spectrum (cruise speed 30km/h, 70km/h max, stall 20-25km/h)
• Flight stability (dihedral 5-6 degrees)
• space and protection for all equipment
• Wingspan MAX! 1.90 m
• Detachable wings and body for easy transport
• Rigid and durable construction
• Servo on the moving parts for easy changing, maintenance, replacement
• For sure electric powered  

Finally anything else you suggest...

And we begin:

1. Uploaded with ImageShack.us
2. Wings are a joint design by the famous Skywalker, the predator RQ-11, an israely Twin-boom (I did not find the name) and some personal touches weight ~ 400gr 

2. Equipment detail

• Battery 250-500g 3s and 4s from 3000-5000 mah
• Futaba 8fg transmitter
• Receiver Futaba 20gr 2,4 8ch
• ESC  GAUI 66Amps 60gr
• Servo 4x12gr digital
• Ardupilot mega for avionics
• 900mhz xbee pro telemetry kit
• transmitter for fpv 5,8 Ghz 200mw ~ 50gr
• camera 10 gr for FPV in the nose without PAN-TITL
• mapping Camera in the belly with pan-roll-stabilization-target tracking 200 gr (I need tons of help with that)
• Target tracking mount 90gr (with Servos)
• 2 camera 6-10 gr at the wingtips for 3d image acquisition
• 136gr Scorpion bl motor SII-3014-1220

3. fuselage,

After much thought for the space, size, versatility, the total weight, I decided to give to my plane a “Stick” form, ie a square carbon fiber of 1,5cm witch all equipment, (wings, rudders etc) will be screwed on it and can change position depending on the setup and CG. The aerodynamic "outfit" will be left out as a surprise at the end of construction, the only hint is that the total weight of the planking will not exceed for 1 meter aircraft 60gr and it will be practically unbreakable! 

4. horizontal and vertical stabs are in shape and size same with those of the skywalker, but is made ​​of balsa & depron (6mm) with normal layout (not T-Tail) and the servos are mounted on them 

Everything is screwed! Because a.  I do not want even traces of glue, and b. the weight. Also I will be literally be able to unscrew everything and put it in a Bag. 

5. Finally, all data from the cameras (dual 640 * 480 3d, RG NIR) will united directly to the base station in a GIS environment, ArcGIS, there the data will be fed into an algorithm that can calculate the terrain, the sunshine and hence the potential evapotranspiration (pennman), various health indices (NDVI, RVI, etc.), leading to immediate conclusions about the course of cultivation.

A little backround,

I am from Athens- Greece, I work as GIS technician for cadastral agencies and forest mapping cartography, I studied agriculture technology and environment management. The whole project has to do with my phd witch I hope to combine spatial data, agriculture techniks and knowledge with remote sensing and the calculation capabilities of GIS.

I purchased a full ardupilot mega kit from udrones ready and tested, I used it to fly right out of the box my custom made telemaster (img below)with perfect results, but I needed something more, so I am building my own airframe, I update my APM’s firmware and now I need some help to make it come to life.

I hope that are many people in this forum that we share the same interests (and passions) and I believe this could be a nice post-think tank to gather all opinions for remote sensing applications. Also I am willing to help everyone who wants to know more about photogrametry and GIS issues, image rectification and so on.

At this point I have to thanks, my employer Silva- Natura , www.greekwings.gr for providing cnc machinery and knowledge for the wing construction and www.nemhobby.com for sponsoring most of my rc gear. 

Thanks in advance,

James Stefanakis