Any engineers or handy types willing to help me build this?

My cats are all indoors to prevent predation on wildlife (and extend their own lifespans). I’d love to build something like this as enrichment for them, but I’d like it to be attractive and well designed. (I’ve also seen an attractive wire mesh version.) It would be wonderful if it was weather-proof enough to leave it in place year round (my cats follow the sunbeams for basking during the days, especially in the winter). Does this appeal to anyone capable of creating a design/instructions?