I was wondering if anyone has recommendations on a good beginner “robot” to program for a ROS2 beginner? As I learn ROS 2 I would love to have something to actually program to help with learning. Originally I was thinking of something like Lego Mindstorms but there doesn’t seem to be much maintained ROS 2 bindings for the Lego SDKs.
I did find Articulated Robotics through another post on this forum which seems to have tutorials built atop Raspberry Pi, would that be any good?
Turtlebot is considered the “official” ROS platform (I don’t know how much official this is, but it essentially holds). TB3 or TB4 will work nice with ROS 2.
Yeah my tutorials are generally a cheaper but more DIY approach. I’ve considered setting up a kit but I think there are enough people out there trying to make robot kits at various price points, each with their own advantages.
The DIY approach is not hard though and it’s a good learning experience 
FYI my tutorials were made for Foxy and are a bit out of date, Build a Mobile Robot with ROS | Articulated Robotics is the beta page with some things updated but others are still behind or somewhat in-progress so just be aware.
I’m also thinking about making a kit/open sourcing my robots: https://youtu.be/0hZVQbW6Lzw
I actually made them because the Create3/TB I have straight up sucks.
The TurtleBot is the officially recommended platform for learning and experimenting with ROS from Open Robotics and our licensed partners. The TurtleBot 3 is much more customisable due to the way it is constructed, while the TurtleBot 4 provides a larger platform ready-to-go out of the box. Both are excellent options, and come with full support from our partners (ROBOTIS and Clearpath Robotics, respectively).
There are also many robots available from other manufacturers to suit a range of budgets. If you want to build one yourself for low cost, the Andino is an excellent choice.
I am a ROS beginner and just got a Turtlebot4. I like it quite a bit, but have had to troubleshoot a lot of self-inflicted issues to get it running. In some ways I could see a build-it-yourself project being even better for learning the whole stack. But I was more curious about SLAM and navigation.
I think I picked up more about ROS2 from going through the official tutorials and some youtube videos. And then working through creating my own nodes to move an arm in simulation. But the turtlebot has certainly been useful for understanding some of the real-world challenges and limitation.