How to handle floating point comparison warnings (DO NOT MERGE)

There are quite a few of these. I've looked at most of them and they are legitimate == 0.0 comparisons when the float was directly set to 0.0. One way to handle them is to turn off -Wno-float-equal. Another is using the mechanism in this pull (or something similar). Looking for comments on what direction to head.
Seems like this one should have some sort of specified delta which is used to determine whether the previous versus new sonar values are different enough to care about. Certainly larger than FLT_EPSILON would seem to be too small to care about.