The paper presents a non-conventional actuator with magnetic fluid, generat
ing low forces and very small displacements, controlled by an electric curr
ent. A comparative study of the two versions is performed by means of the t
ransfer characteristics. The device might he used in the fine control of so
me small mechanisms (e.g., the blades of the pneumatic and hydraulic pressu
re: amplifiers of a flapper-nozzle type). (C) 2000 Elsevier Science S.A. Al
l rights reserved.