creating a double-curved surface/mesh with a panels.

Hello My name is Minwoo a 5th Year Architecture student at Oklahoma State University.

I am fairly new to this program and i was trying to see if i could create a set of panels along a concave surface. it seems to be working fine in the top. but the problems come when the panels starts to taper/morph towards the bottom of corners.. 

I dont mind the panels eventually being trimmed when it overruns the four edges but i would like to have more control over the sizes of the panels and if possible the shape of the panels at the end. and the most important thing being the triangles to be regular somewhat like the grey shape on the back.....

Please help!!

If any questions please feel free to email me at minwoo.hahm@okstate.edu

thank you!