Guy B;
we have been able to get about 1/4" per foot bend on a 24ft. long steel panel, you should be able to do the same with OSB, but it is not enough to get the desired look on you photo.
I was involved with a mfg. where we built a custom form for metal panels in about a 12ft radius. laminated in a custom vacuum bag. Problem is you could only build one every hour