Marine
more Grasshopper Widgets
Used only two GH components to divide each flap axis by ten and create a "plane" at each point, perpendicular to the axes. One more GH component ('SubSet') sifted out the planes at the end of each axis:
A bit more effort to intersect those planes with the original flap surfaces to produce nine intermediate foil sections per flap, then rotate them "appropriately":
Then more effort to loft them with the end curves - most precise yet:
Skipping the surface lofting, here are animations showing plus/minus 25 degrees at five degree increments, for three "graph mapper" conditions: