I helped out at a science fair, demonstrating some basic robots, but then someone suggested entering the PiWars robotics competition for 2022. This was a big distraction, so here's some basic pictures and links. If there aren't many updates here, its because there's lots of updates elsewhere. There's a blog and a website with updates of what we built.
PiWars 2022 is about building farm robots, particularly to solve 4 challenges typical of a farm. Full details are on their website here. There are lots of great robots described so definitely worth looking at.
PiWars 2023 has been postponed becoming PiWars 2024 and replaced by a Hacky Racers competition which I'm not entering, I'm mean, and the entry equipment cost looked beyond me.