1. Cats enjoy being petted because it reminds them of being groomed by another cat.
2. Ants are one of the few insects that practice social grooming.
3. It should be possible to "pet" an ant.
Now I don't think just rubbing would work. You need to mimic what ants do.
So maybe ... like... a tiny damp cotton swab? It would be very hard to get the pressure and motion right without scaring the ant. But, I still think the facts indicate ant petting should be possible.
Have you ever "pet" an ant?