Hello my dearest physics teacher, I used to have a few motors that only ran on 0 or 100% based on the battery switch, then I bought an Sbrick plus which enables remote control from android or a computer, has 4 outputs with variable voltage or can be used as inputs for WeDo sensors, supports programming in Scratch. I had a lot of fun with it and even though it's a third party device it has many advantages over official lego programmable or r/c units. If you're still into Lego you can try
I love the sun tracking idea. How much weight can the tanks handle? I'm curious as to how large of a solar panel could be mounted. And the energy consumption of the unit? I'm wondering how much of the energy generated would be required to operate the tanks.
