Modeling and Control of Flexible Structures in Frequency Domain

In this paper, distributed parameter-dependent modeling and control approaches are proposed for flexible structures. The distributed model is motivated from distributed control design, which is advantageous in reducing control implementation cost and increasing control system reliability. This modeling approach mainly relies on a central finite difference scheme to capture the distributed nature of the flexible system. Based on the proposed distributed model, a sufficient synthesis condition for the design of a distributed output-feedback controller is presented using induced L2 norm as the performance criterion. The controller synthesis condition is formulated as linear matrix inequalities, which are convex optimization problems and can be solved efficiently using interior-point algorithms. The distributed controller inherits the same structure as the plant, which results in a localized control architecture and a simple implementation scheme. These modeling and control approaches are demonstrated on a non-uniform cantilever beam problem through simulation studies.

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Frequency Domain Uncertainty Modeling and Quantification of the Laser Metal Deposition Process

Volume 2: Mechatronics; Mechatronics and Controls in Advanced Manufacturing; Modeling and Control of Automotive Systems and Combustion Engines; Modeling and Validation; Motion and Vibration Control Applications; Multi-Agent and Networked Systems; Path Planning and Motion Control; Robot Manipulators; Sensors and Actuators; Tracking Control Systems; Uncertain Systems and Robustness; Unmanned, Ground and Surface Robotics; Vehicle Dynamic Controls; Vehicle Dynamics and Traffic Control ◽

10.1115/dscc2016-9777 ◽

2016 ◽

Author(s):

Patrick M. Sammons ◽

Douglas A. Bristow ◽

Robert G. Landers

Keyword(s):

Frequency Domain ◽

Uncertainty Modeling ◽

Deposition Process ◽

Metal Deposition ◽

Great Promise ◽

Laser Metal Deposition ◽

Modeling And Control ◽

Metal Parts ◽

Modeling Uncertainties ◽

And Control

Additive Manufacturing (AM) is a growing class of manufacturing processes where parts are fabricated by repeated addition of material. Many of these processes show great promise for the production of complex, functional parts for use in critical applications. One such process, Laser Metal Deposition (LMD), uses a laser and a coaxial blown metal powder source to produce functional metal parts. However, it has been demonstrated that the LMD process possesses complex two-dimensional dynamics which, when not appropriately accounted for in the modeling and control stages, can lead to build failures. Additionally, even when the two-dimensionality of the process is accounted for, modeling and process uncertainties can lead to degraded performance or instability. Here, in the context of a control oriented model of the LMD process developed previously, process and modeling uncertainties are modeled and quantified in the frequency domain.

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Preface of the "Symposium on new methods for modeling and control of flexible structures and robots"

10.1063/1.4825741 ◽

2013 ◽

Author(s):

Laura Celentano

Keyword(s):

Flexible Structures ◽

Modeling And Control ◽

New Methods ◽

And Control

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Flexibility control of flexible structures. Modeling and control method of bending-torsion coupled vibrations.

JSME international journal Ser 3 Vibration control engineering engineering for industry ◽

10.1299/jsmec1988.31.575 ◽

1988 ◽

Vol 31 (3) ◽

pp. 575-582 ◽

Cited By ~ 1

Author(s):

Toshio FUKUDA ◽

Fumihito ARAI ◽

Hidemi HOSOGAI ◽

Nobuyuki YAJIMA

Keyword(s):

Control Method ◽

Flexible Structures ◽

Modeling And Control ◽

Coupled Vibrations ◽

And Control

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Modeling and Control of Noncollocated Flexible Structures

IFAC Proceedings Volumes ◽

10.1016/s1474-6670(17)40020-6 ◽

1998 ◽

Vol 31 (27) ◽

pp. 153-158

Author(s):

Natalya Raskin ◽

Yoram Halevi

Keyword(s):

Flexible Structures ◽

Modeling And Control ◽

And Control

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Modeling, Control, and Design of Flexible Structures: A Survey

Applied Mechanics Reviews ◽

10.1115/1.3119163 ◽

1990 ◽

Vol 43 (5) ◽

pp. 99-117 ◽

Cited By ~ 32

Author(s):

S. S. Rao ◽

T. S. Pan ◽

V. B. Venkayya

Keyword(s):

Research Work ◽

Flexible Structures ◽

Space Applications ◽

Location Selection ◽

Modeling And Control ◽

Thermal Transients ◽

Large Structures ◽

Effective Operation ◽

And Control ◽

Dynamic Excitations

Large structures used in space applications, are made flexible to reduce the high cost of lifting mass to orbit. These highly flexible structures will inevitably be vulnerable to dynamic excitations caused by the slewing/pointing maneuvers, thermal transients, operations of on-board coolers and generators, etc. Thus the aspects of modeling and control become extremely important for the safe and effective operation of large flexible structures (LFS’s). The theoretical, computational, and practical methodologies developed during the last decade along with the latest trends in this area are described. The research work addressing the aspects of model reduction, passive and active control, hierarchical/decentralized control, integrated structural and control design, optimal design, and sensor/actuator location selection problem for large flexible structures is discussed.

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