Discussions

Hello Guys,
I'm currently searching a quadrocopter for my bachelor thesis at a Swiss university for applied sciences. The problem is, there is a TON of stuff out there and i hope you guys can help me to narrow down my results.
 
My Project:
The quad will be equipped with a camera at the bottom (connected to a external PC for the moment). The ground station PC (Linux, C++ with ROS and OpenCV) analyses the data and sends commands back to the quadrocopter via MAVLink.

For example: the camera picture indicates that the drone is drifting => move in that direction T(x,y,z) with a certain speed until desired position is reached.

Here is what the Quad needs to be able to do:
- Autonomous and controlled takeoff and landing

- Visual stabilization with the camera=> hold position. Not "just" an optical flow sensor. The image must get to the PC and has to be processed there, to analyze patterns such as QR-Codes.

- I would love to use the ROS platform (for future integration of SLAM and sensor fusion)

- (not essential) adding a few sonar sensors for collision avoidance

- Payload: unknown USB-Camera, but for future projects i would like to do the calculations on board with a Pandaboard and add a laser rangefinder.



Here what i think:
-PC communicates with UAV over xBee using MAVLink
-PC gets live video feed from the camera on the UAV pointing downwards (for now connected with USB/LAN to reduce latency)


[  ]<-----xBee (MAVLink)----->Autopilot
|PC|
[  ]<---LAN or USB--- Camera

 
I found a "good" overview at http://multicopter.org/wiki/Multicopter_Table but here my findings narrowed down to a few:

- Arducopter:
    (+)RTF-Kits, MAVLink, ROS(?) (not sure if that works), Open source, "cheap"
    (-)

- Mikrocopter:
    (+)RTF-Kits, MAVLink, ROS, kind-of-Open source, frame-blueprints available
    (-)

- AscTec Pelican
    (+)fast onboard CPU, easy to add sensors (written on the homepage)    
    (-)expensive

- UAVP-NG:
    (+)good hardware, Open source
    (-)no ROS/MAVLink

- AR-Parrot
    (+)cheap, ready to fly, ROS
    (-)payload to low, low quality

- PX4    (+)supports MAVLink, ROS, compatible with ar-drone frame, Open source, Swiss product ;)
    (-)no kits available



Right now i think a good choice would be the "Arducopter 3DR Quad" or the"Mikrocopter QuadroXL".

I am at a point, where i get more and more confused, the more i read ;)
So i would really appreciate some pointers, to know in what direction I’ll have to go.
What do you think, would be the best fit for my needs?
Or is there even a better platform that i did not consider?



Thank you in advance,

Tom