Just like to share my project I started almost a year ago. It’s a suite of various ROS compatible platforms mainly 2WD, 4WD, Mecanum Drive and Car-Like robots.
I have posted a tutorial on how to build each platform at http://linorobot.org . Since it’s supposed to be homebrew, most of the parts are easily accessible and comparatively cheap. The controller’s using a Teensy 3.2 board and uses a Radxa Rock Pro as its main computer. It’s also got a XV-11 Lidar for mapping and localization so users can have an end-to-end learning experience with ROS. I tried to make the design as modular and scalable as possible so it can be used for much bigger robots as well (hopefully).
Please feel free to criticise, suggest or ping me for interested collaborators or mentors.