Input: yellow pulley.
Internal gear (35 teeth) is stationary. Pink nut is fixed to the pink gear (30 teeth). The nut of circular grooves rotates in eccentric hole (in pink) of the yellow pulley. The nut can roll on the screw thus reduces the friction.
Output: green screw (lead = t2) moving linearly an amount of t2 in 1 revolution of the input.