Crazyflie Nano C++ Client Library

First of all, the Crazyflie Nano is an awesome Quadcopter by the guys at Bitcraze. I just love it - and since I'm a C/C++ programmer deep in my heart, I really, really wanted to have a client library in that language (there was none at that time).

That's why I wrote one.

My work is based on Bitcraze's Python Library (see their repos) which (alongside their wiki) greatly helped me understand the communication protocol. Feel free to use the library as you like, as long as you obey the rules of the BSD license.

You can check out the current Doxygen source code documentation here.

What this library is

• A USB connection point to the Crazyflie Nano quadcopter by Bitcraze
• An abstraction layer for the different messages you can send your copter
• A controller framework for controlling the Crazyflie using cartesian coordinates
• A C++ entrypoint for programmers that write programs in C++ (rather than Python)
• The first version was developed, written and maintained completely by me (Jan Winkler)
• Development and maintenance is distributed over the many contributors by now. This is a good time to say: Thank you!

What this library is not

• A bootloader
• Complete
• Bug-free (although I'm trying really hard!)

Dependencies

The lib depends on GLFW, which you can install under Ubuntu by apt-get install'ing this:

sudo apt-get install libglfw-dev libglfw2 cmake

How to build the library

First, clone the repository:

$ git clone https://github.com/fairlight1337/libcflie.git

In the cloned folder, do:

$ mkdir build
$ cd build
$ cmake ..
$ make

After that, you will find two directories in the base directory: lib and bin.

• lib includes the built libcflie library (with fitting extension, depending on where you build it). You can link against this library, using the header files contained in include/cflie/ to actually use it.

• bin includes example programs. Currently, there are two:

  • ex-simple shows the most simple usage example of the library
  • ex-replugging shows how to use the lib for allowing re-plugging the USB dongle and letting the copter go out of range and return. Also, event hooks are marked for all these events to execute custom code for all situations.
  • ex-gui displays an OpenGL window that shows a plane based on the current copter orientation. Using the arrow keys, you can control the copter, and when pressing the space bar, you can increase the thrust to the copter. CAREFUL: When starting the program, the copter will start with a thrust greater than 10000, which will start the engines! So be sure to place it far away from objects (or your hands).

How to run the examples (or you own programs)

When running programs linked against and using libcflie, you have to have access permissions for your USB devices set up correctly.

You basically have two options:

1. Run your programs as root. For the ex-gui example, this would mean (starting from the libcflie/build directory after typing make):

sudo ./../bin/ex-gui

Exit the example by pressing ESC.

2. Set up your USB permissions for the CrazyRadio dongle (this is the recommended way). For this to work, create a new file at /etc/udev/rules.d/99-crazyradio.rules and put this line into it:

SUBSYSTEM=="usb", ATTRS{idVendor}=="1915", ATTRS{idProduct}=="7777", MODE=="0664", GROUP=="plugdev"

Now replug your dongle and you're set. Start it with:

./../bin/ex-gui

Again, exit the example by pressing ESC.