This is the technology of HD Rumble

[SonytendoAmiibo]

SWORDF1SH said:
Dualshock 4 can vibrate in a way that can fool you there is something rattling around in the controller like demoed on the Playroom. I'm not sure what HD rumble does that much better. It seems it's good for battery life though.

Very good for battery life with the drawback being they only work at one frequency. I think Nintendo has built an array of linear resonance actuators inside each Joy-Con as to cover a wide range of frequencies.