DESIGN OF A HYDRAULIC ACTUATOR FOR ACTIVE CONTROL OF ROTATING MACHINERY

A hydraulic actuator was designed and is described herein. This actuat or consists of: a pump, which generates the nominal pressure, a hydrau lic servovalve, and a thin elastic plate, which transduces the generat ed pressure variations into forces acting on a mass, which simulates t he bearing of a rotor system. An actuator characteristic number is def ined to provide a base for an optimum design of force actuators with c ombined weight, frequency, and force considerations. This characterist ic number may also be used to compare hydraulic and electromagnetic fo rce actuators. In tests this actuator generated 182.3 N force at a fre quency of 100. Hz. and a displacement amplitude of 5.8 x 10(-5) m.