The kobuki base on your own won't drift, so it is sensible that the tilted inertia leads to the drift. Not surprisingly I am able to hack my URDF which has a weightless superstructure, but I planned to take care of this in a more practical way. I attempted all https://www.uk-exhibitionstands.co.uk/product/monolith-3m-display-wall-3x2-4/