VPI&SUjAIAA SYMPOSIUM ON DYNAMICS AND CONTROL OF LARGE FLEXIBLE STRUCTURES

WITH PASSIVE DAMPING by Thomas E. Alberts, Ph.D Candidate Gordon G. Hastings, Ph.D Candidate Wanye J. Book, Professor and ,Stephen L. Dickerson, Professor Department of Mechanical Engineering Georgia Institute of Technology Atlanta, Georgia 30332 This paper presents a hybrid active and passive control scheme for control ling the motion of a lightweight flexible arm. A straightforward developement of LaGrange's equations using a series expansion of assumed flexible modes provides a time domain model for contro11er design. The active controller design was approached as a steady state linear quadratic continuous regulator. A constrained viscoelastic layer treatment was employed to achieve passive damping. The passive damping treatment serves to enhance the system's stability whi le providing sound justification for the use of a highly truncated dynamic model and reduced order controller. Initial experim~ntal results comparing controller performance with and without passive damping demonstrate the merit of the proposed combined active/passive approach. Introduction -----------~ Recently a considerable volume of literature has been devoted to the problem of controlling the motions of structures having flexible structural members. While much of this research is performed in the interest of control ling large spac~craft, several investigators [1-6J have considered applying similar principles to the control of industrial