The kobuki foundation by itself will not drift, so it makes sense which the tilted inertia causes the drift. Naturally I can hack my URDF having a weightless superstructure, but I wished to resolve this in a more real looking way. I tried all I can contemplate, and all unsuccessful: https://www.uk-exhibitionstands.co.uk/the-power-of-custom-exhibition-stands-for-maximum-brand-impact/