I wonder how much a few simple maintenance bots could help, basically a solar roomba that opportunistically travels along the roof, zig-zagging as far in a day

I wonder how much a few simple maintenance bots could help, basically a solar roomba that opportunistically travels along the roof, zig-zagging as far in a day as much or little in a day as it's energy supply allows. Something like that clearly can't work for a small installation, but when a city has a network of roofed bike paths, you'd expect first glimpses of economy of scale. Could nicely hit a sweet spot between doable, futuristic, real-life utility and not served by commercial offerings for a university project.