Cross Belt Drive:
When shafts are rotating in the opposite direction, cross belt drive can be obtained.
In the diagram given to us pulley 'A' is called as driver pulley as it is attached with the rotating shaft. Velocity ratio is same as for the open belt
V.R. = N2/N1 = D1/D2
If thickness of belt 't' is given to us then
V.R = N2/N1 = (D1 + t)/(D2 + t)