Active disturbance rejection control

Active disturbance rejection control (or ADRC, also known as automatic disturbance rejection control) is a model-free control technique used for designing controllers for systems with unknown dynamics and external disturbances. This approach only necessitates an estimated representation of the system's behavior to design controllers that effectively counteract disturbances without causing any overshooting.

Source: Wikipedia — Active disturbance rejection control (CC BY-SA 4.0)