A.R.Drone Developer Guide - Abstract

Let’s now detail the ARDroneTool part :
• ardrone_tool.c : contains a ready-to-use main C function which initialises the Wifi network
and initiates all the communications with the drone
• UI : contains a ready-to-use gamepad management code
• AT : contains all the functions you can call to actually control the drone. Most of them
directly refer to an AT command which is then automatically built with the right syntax
and sequencing number, and forwarded to the AT management thread.
• NAVDATA : contains a ready-to-use Navdata receiving and decoding system
3.3 The AR.Drone Tool
Part of the AR.Drone Library is the ARDroneTool .
The ARDroneTool is a library which implements in an efficient way the four services described
in section 2.10.
In particular, it provides :
• an AT command management thread, which collects commands sent by all the other
threads, and send them in an ordered manner with correct sequence numbers
• a navdata management thread which automatically receives the navdata stream, decodes
it, and provides the client application with ready-to-use navigation data through a callback
function
• a video management thread, which automatically receives the video stream and provides
the client application with ready-to-use video data through a callback function
• a control thread which handles requests from other threads for sending reliable commands
from the drone, and automatically checks for the drone acknowledgements.
All those threads take care of connecting to the drone at their creation, and do so by using the
vp_com library which takes charge of reconnecting to the drone when necessary.
These threads, and the required initialization, are created and managed by a main function, also
provided by the ARDroneTool in the ardrone_tool.c file.
All a programmer has to do is then fill the desired callback functions with some application
specific code. Navdata can be processed as described in section 5.3. The video frames can be
retrived as mentionned in 5.6.
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