ROS node for Pozyx connected with I2C

See https://github.com/heivi/Pozyx-Linux-library for more information on installing the Pozyx library on RPi/Linux.

The Pozyx library is included as submodule, so you can either pass --recursive to git clone or run

git submodule init
git submodule update

You should change CMakeLists.txt if you don't use pigpio -library.