The kobuki base alone won't drift, so it is smart that the tilted inertia results in the drift. Of course I can hack my URDF with a weightless superstructure, but I needed to fix this in a more realistic way. I tried all I'm able to contemplate, and all unsuccessful: https://www.uk-exhibitionstands.co.uk/product/casonara-tower-360o-light-box-display-100s/