publications by Devendra P Garg.

Papers Published

1. Anderson, Gary L. and Garg, Devendra P., Active vibration control in rotorcraft systems using smart actuators, Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, vol. 3 (2002), pp. 1864 - 1874 .
   (last updated on 2007/04/10)

   Abstract:
   This paper reports several advances in research made toward controlling unwanted vibrations in rotorcraft systems. Usually, these vibrations arise from a non-steady and aerodynamically complex environment in which a rotorcraft (e.g., a helicopter) operates. The other major sources of vibration include the structurally coupled rotating components in the engine, the transmission system, and the rotor. Smart actuators can be gainfully employed for active control of vibrations by providing aerodynamic stability and appropriate shape and stress distribution in the structure. A smart structure is generally composed of a number of distributed sensors and actuators embedded and/or surface-mounted on a structure. In addition, it incorporates one or a series of microprocessors that analyze the data received from the sensors and command the actuators to take appropriate corrective action as directed by the specific control strategy in use. Typical means used for smart sensing/actuation include piezoelectric materials, shape memory alloys, electro-rheological and magneto-rheological fluids, electro-strictive and magneto-strictive materials, and fiber optics. The paper discusses the progress made in the research projects sponsored by the Army Research Office and the National Rotorcraft Technology Center (NRTC) that are being conducted at various universities and other Army locations. Several of these projects address a number of issues dealing with systems prone to vibratory motions that could become severe when resonance, limit cycle, chaotic, or aeromechanical instability conditions were approached.

   Keywords:
   Vibration control;Actuators;Aerodynamics;Stress concentration;Sensors;Surface mount technology;