Plan view.
Green sails are so pivoted as to present their edges in returning toward the wind, but to present their faces to the action of the wind, the direction of which is supposed to be as indicated by red arrow.
Blue bar rotates on the eccentric of a pink fixed shaft.
Output motion (clockwise rotation) is taken from a gear fixed to the yellow disk.
The mechanism can be applied for simple water turbines (no need of flow guide).by adding more sails.