In all the cars I've driven that has ABS, the feature activates at all speeds for as long as it detects a locked wheel. So sudden braking on uneven roads even at low speeds will usually trigger it.
That is what i know as well. My abs activated in a parking lot with painted floor. Kakagaling lang sa labas umuulan.
For modern cars, the EPS seems to be more ubiquitous as the traditional engine-driven PSF...
A/c