Cant bake a diffuse map

I’ve gone through many tutorials as well as googling this issue… and I simply can’t figure out what am I doing wrong. Materials should be assigned to a UV map and baking settings seem correct.

I am attaching the corresponding file and I’d be super grateful for help. I spent at least 2 hours trying to figure it out and couldn’t.

here’s the blender file: https://drive.google.com/open?id=1H6sgXSWSzUIoM00IV-5rupSGe0vMKL8J

and a corresponding obj: https://drive.google.com/open?id=1PoSnya4zDebq4qlEIi6xNAVVyC-0-jlu