Hey @ThiloZimmermann,
we submitted to the contest the project we asked for help here:
https://discourse.ros.org/t/imcoders-easy-to-install-and-cheap-odometry-sensors/5543/
Actually, right now we are preparing the last part for the final on 22nd October (link to the hackaday contest project)
Why were you asking, by the way? If you have any question regarding it, feel free to ask 