RSS Rotary Steerable Drilling System
Introduction

The RSS rotary steerable drilling system described here operates on the principle of the application of a side force in a similar way to the non-rotating Steerable Mud Motor described before. 

However, in RSS rotary steerable drilling system it is also possible to rotate the drill string (Check Also Bottom Hole Assembly Components & Design) even when drilling directionally (Check Also : Directional Drilling Guide).
https://www.drillingmanual.com/rss-rotary-steerable-system-autotrak-baker-hughes/