Experiments in control of flexible structures with noncolocated sensors and actuators

Positive position feedback (PPF) control is widely used in active vibration control of flexible structures. To ensure the vibration is quickly suppressed, a large PPF scalar gain is often applied in a PPF controller. However, PPF control with a large scalar gain causes initial overshoot, which is undesirable in many situations. In this paper, a fuzzy gain tuner is proposed to tune the gain in the positive position feedback control to reduce the initial overshoot while still maintaining a quick vibration suppression. The fuzzy system is trained by the desired input-output data sets by batch least squares algorithm so that the trained fuzzy system can behave like the training data. A 3.35 meter long I-beam with piezoceramic patch sensors and actuators is used as the experimental object. The experiments include the standard PPF control, standard PPF control with traditional fuzzy gain tuning, and PPF control with batch least squares fuzzy gain tuning. Experimental results clearly demonstrate that PPF control with batch least squares fuzzy gain tuner behaves much better than the other two in terms of successfully reducing the initial overshoot and quickly suppressing vibration.

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Distributed active vibration cooperative control for flexible structure with multiple autonomous substructure model

Journal of Vibration and Control ◽

10.1177/1077546320909968 ◽

2020 ◽

Vol 26 (21-22) ◽

pp. 2026-2036

Author(s):

Xiangdong Liu ◽

Haikuo Liu ◽

Changkun Du ◽

Pingli Lu ◽

Dongping Jin ◽

...

Keyword(s):

Vibration Control ◽

Cooperative Control ◽

Vibration Suppression ◽

Control Strategies ◽

Active Vibration Control ◽

Flexible Structures ◽

Lyapunov Theory ◽

Sensors And Actuators ◽

Active Vibration ◽

Distributed Cooperative Control

The objective of this work was to suppress the vibration of flexible structures by using a distributed cooperative control scheme with decentralized sensors and actuators. For the application of the distributed cooperative control strategy, we first propose the multiple autonomous substructure models for flexible structures. Each autonomous substructure is equipped with its own sensor, actuator, and controller, and they all have computation and communication capabilities. The primary focus of this investigation was to illustrate the use of a distributed cooperative protocol to enable vibration control. Based on the proposed models, we design two novel active vibration control strategies, both of which are implemented in a distributed manner under a communication network. The distributed controllers can effectively suppress the vibration of flexible structures, and a certain degree of interaction cooperation will improve the performance of the vibration suppression. The stability of flexible systems is analyzed by the Lyapunov theory. Finally, numerical examples of a cantilever beam structure demonstrate the effectiveness of the proposed methods.

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Force Feedback in Adaptive Trusses for Vibration Isolation in Flexible Structures

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2801267 ◽

1997 ◽

Vol 119 (3) ◽

pp. 365-371 ◽

Cited By ~ 13

Author(s):

W. W. Clark ◽

H. H. Robertshaw

Keyword(s):

Vibration Isolation ◽

Force Feedback ◽

Flexible Structures ◽

Control Law ◽

Control Problems ◽

Sensors And Actuators ◽

Dynamic Forces ◽

Active Vibration ◽

The Ideal

This paper addresses the transmission of unwanted vibrations in flexible structures by actively minimizing dynamic forces seen at critical locations within the structure. An adaptive truss serves as an active interface between the two isolated sides of the structure, and force-feedback within individual links of the truss is the governing control law. The use of an adaptive truss allows the problem to be viewed as a set of localized control problems with collocated sensors and actuators. This paper first discusses the ideal capabilities of force feedback for active vibration isolation, and then presents the analytical and experimental results of a case study which shows significant reduction in transmitted vibrations.

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Active Control of a Plate Using Segmented Distributed Sensors and Actuators: Finite Element Development and Analysis

ASME 1991 Computers in Engineering Conference: Volume 2 — Finite Elements/Computational Geometry; Computers in Education; Robotics and Controls ◽

10.1115/cie1991-0119 ◽

1991 ◽

Author(s):

H. S. Tzou ◽

H. Bahrami

Keyword(s):

Finite Element ◽

Active Control ◽

Variational Equation ◽

Flexible Structures ◽

Monitoring And Control ◽

Sensors And Actuators ◽

Distributed Sensors ◽

Computation Efficiency ◽

Piezoelectric Structure ◽

And Control

Abstract Distributed sensing and control of flexible structures have drawn much attention in recent years. Piezoelectric elements can be used with an elastic structure as sensors and actuators for structural monitoring and control applications. This paper presents a development of a thin piezoelectric finite element applied to active control of flexible structures. A piezoelectric finite element is derived using the variational equation and Hamilton’s principle. System equations of a piezoelectric structure are formulated accordingly. Guyan’s reduction technique is incorporated to improve the computation efficiency. Feedback control algorithms are also derived and implemented in the finite element code. Applications of the technique to a plate with segmented distributed sensora/actuators are studied and effectiveness evaluated.

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Dependent modal space control: Experimental test rig

Journal of Vibration and Control ◽

10.1177/1077546315616699 ◽

2015 ◽

Vol 23 (15) ◽

pp. 2418-2429 ◽

Cited By ~ 3

Author(s):

Mattia Serra ◽

Ferruccio Resta ◽

Francesco Ripamonti

Keyword(s):

Mode Shape ◽

Experimental Validation ◽

Flexible Structures ◽

Spillover Effects ◽

Control Technique ◽

Mode Shapes ◽

State Variables ◽

Control Logic ◽

Sensors And Actuators ◽

Modal Space

This article presents the experimental validation of a new control technique for reducing vibration in flexible structures: Dependent modal space control. While the classic independent modal space control allows only the frequency and the damping of the controlled modes to be changed, dependent modal space control can also impose the controlled mode shapes. Depending on the kind and number of sensors and actuators available for control, the mode shape can be imposed in both a direct and an indirect way. Owing to the need for modal sensors and actuators for direct mode shape imposition, the second methodology is often preferred in many engineering applications. In the indirect method, the optimal closed loop mode shapes set is computed with an optimization algorithm in order to minimize an Input-Output Performance Index. The worsening spillover effects due to errors in the estimates of the system state variables are considered when computing the gain matrix and play an important role in the entire control logic. Experimental validation on a cantilevered beam shows the effectiveness of the dependent modal space control and a good match between the numerical and the experimental results.

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