Class Of Flexible Structures Research Articles

Active control for flexible mechanical systems with mixed deadzone-saturation input nonlinearities and output constraint

There exist mixed deadzone-saturation input nonlinearities and output constraint in the practical implementation environment for flexible mechanical systems, and they have crucial influences on the performance of flexible systems. In this paper, two class of flexible structures are investigated and analyzed by designing the active boundary vibration control with auxiliary systems. Based on the infinite dimensional dynamic model of flexible mechanical systems, the barrier logarithmic terms are brought into the Lyapunov function and boundary vibration control laws for maintaining the output signals within the constrained region. Besides, the auxiliary terms are designed in the control laws to compensate for mixed nonlinear inputs which integrate the deadzone and saturation characteristics. With the simulation results, the theoretical analysis for the flexible mechanical systems is verified to be correct and the designed control laws are effective.

Adaptive control strategies for flexible space structures

The problem of controlling flexible space structures in the presence of significant uncertainties using only position measurements is considered. Adaptive controllers, which are capable of controlling partially known dynamical systems and delivering good performance by providing a time-varying compensation on-line, are desirable for such system. We present an adaptive controller which can globally stabilize a class of flexible structures. This controller is applicable whether position measurements, rate measurements, or combinations thereof are available, as well as for colocated and noncolocated actuator-sensor pairs that are sufficiently close. The improvement in performance generated using such controllers is demonstrated using two practical structural system.

動的アクチュエータを先端にもつ柔軟構造物の安定化

動的アクチュエータを先端にもつ柔軟構造物の安定化

On-line identification design for a flexible beam laboratory adaptive control experiment

Experience with system identification design for a flexible beam laboratory experiment adaptive controller is discussed. Among the limitations faced were the presence of unmodelled high frequency modes and the use of an accelero-meter as the primary motion sensor. These limitations motivated the development of a novel robust identification approach which is applicable to a large class of flexible structures.

On the elastic mode estimation aspect of a class of multibody flexible systems

An investigation pertaining to estimation of the elastic generalized coordinates for a given class of flexible structures is presented. To begin with, a model for studying nonlinear dynamics of the structure is described. The governing equations of motion are obtained using the Lagrangian procedure with modal discretization. Next, deformations caused by rapid slewing maneuvers are estimated using the least square estimation approach. As an alternative, a procedure based on the operator spline technique is proposed and its potential assessed. It is motivated by the need for achieving an on-line estimation procedure permitting real time control. Finally, a comparative performance study of the two procedures is undertaken using a simplified model of the flexible system.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>