I was comparing the wheels of the Curiosity rover and the Perseverance rover and noticed that the latter had a very flat cylindrical design as compared to the former.
This got me thinking about which wheel profile was sturdier. That got me thinking about various things that might be different. Intuitively, I felt that the convex wheel would be better off because it would be able to transfer some of the applied force into normal components, which would keep the shear stresses lower (Aluminum 6061 has a shear strength of only 207 MPa, compared to the tensile yield strength of 276 MPa).
So I decided to test it on Ansys:
From these, I can visibly see that the regions of maximum stress are lower in the convex wheel. But I am starting to doubt if I'm misreading something. Could someone knowledgable help?
Among convex and flat profiles, which one is sturdier? (If you feel the word sturdy is ambiguous, please interpret it as "less metal fatigue", perhaps.)