Bitcraze Forums

I have a couple of nanos on order and have been reading-up on the source and such. But I do have two questions:

1) Has anyone tried putting fiduciary markers on a nano (maybe a couple of colored balls) and try to track its position using something like OpenCV?

2) And if someone is tracking it using an image recognition system, have they considerd some sort of indoor GPS-like algorithm for controlling its position?

And one final question... I see the GitHub with the PC-side client software, which would send messages to the copter regarding movement. Is that message protocol well-documented somewhere? I wouldn't mind writing a program that sends those commands directly without using the PC-client software. In the meantime, I'll just look at the crazyflie-clients-python directories.

Thanks in advance,

Brian

Hi,

1) Yes tracking the Crazyflie with OpenCV and a reb ball has been done: https://www.youtube.com/watch?v=UzFwg2Fpv4E. Since that first try, there has been other people doing a much better job like Oliver Dunkley here: https://www.youtube.com/watch?v=-zlpJ9Yo93U. We have also seen people using a vincon system but that cannot be done at home .

2) I have not seen local positioning system done, but I have a vision of plugging camera and Crazyradio to rasbery pies and having them broadcasting what they see (thing like red ball on this line, green ball that line). Then copers receiving info from many camera would be able to calculate there position in the room. Putting such device in all room corner of a building would allow navigation in the building. Also we have experimented with neopixel RGB leds that would allow to make a dynamic marker and encode the id of the copter in the marker (also making the tracking more immune to the environment color by changing it dynamically). That only my personal master plan for the local positioning system and until now I have had no time for it :-s...

The protocol is documented on our wiki. We still have a lot of cleanup work to do on the documentation though, at worst we have the python and firmware C code that can be read. The message needed to control the Crazyflie is the commander packet: http://wiki.bitcraze.se/projects:crazyf ... =commander it is sent on port 3 channel 0 with this packet format: http://wiki.bitcraze.se/projects:crazyf ... _structure. The Crazyradio USB protocol is also documented: http://wiki.bitcraze.se/projects:crazyradio:protocol

Best regards,
/Arnaud

Thank you. That's perfect information.

As it gets colder and my outdoor flying days get shorter, I'll probably spend more time with my Crazyflie and some indoor GPS work.