Comment by matsemann

In my thesis many years ago [0] I used EAs to build bicycle wheels. They were so annoyingly good at exploiting whatever idiosyncrasies in my wheel-simulator. Like, the first iterations of my simulator it managed to evolve wheels that would slowly oscillate due to floating point instability or something, and when applied forces to it would increase and increase until the whole simulator exploded and the recorded forces were all over the place, of course then out-competing any wheel in at least some objective dimension.

After fixing those bugs, I mostly struggled with it taunting me. Like building a wheel with all the spokes going from the hub and straight up to the rim. It of course would break down when rolling, but on the objective of "how much load can it handle on the bike" it again out-competed every other wheel, and thus was at the pareto-front of that objective and kept showing up through all my tests. Hated that guy, heh. I later changed it to test all wheels in at least 4 orientations, it would then still taunt me with wheels like (c) in this figure[1], exploiting that.

[0]: https://news.ycombinator.com/item?id=10410813 [1]: https://imgur.com/a/LsONTGc