Optimal Piezoelectric Sensors and Actuators Deployment for Active Vibration Suppression of Satellite Antenna Reflector

2012 ◽  
Vol 479-481 ◽  
pp. 1490-1494 ◽  
Author(s):  
Wen Bo Li ◽  
Xiao Ran Li ◽  
Zhi Gang Zhao ◽  
You Yi Wang ◽  
Yang Zhao

To solve the problem of active vibration control for satellite antenna reflector, which is weak damping and closely spaced modes, the optimal actuators/sensors deployment and controller designing need to be considered. Firstly, the optimal criterions of controllability and observability are designed according to the specificity of Gram Matrix eigenvalue in satellite antenna system equations. Secondly, based on the above criterions, piezoelectric materials (as sensors and actuators) and genetic algorithm are utilized to optimize the deployed locations of sensors and actuators. Finally, to suppress the vibration of satellite antenna reflector, a Linear Quadratic Gaussian (LQG) controller is designed under the impulse and white noise excitation respectively. The simulate results show the effectively deployed locations of sensors and actuators, and the correctness of designed LQG controller.

2020 ◽  
Vol 26 (21-22) ◽  
pp. 2026-2036
Author(s):  
Xiangdong Liu ◽  
Haikuo Liu ◽  
Changkun Du ◽  
Pingli Lu ◽  
Dongping Jin ◽  
...  

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.


Author(s):  
Hassan Ali Kadhem ◽  
Ahmed Abdul Hussein

Active vibration control is presented as an effective technique used for vibration suppression and for attenuating bad effects of disturbances on structure. In this work Proportional-Integral-Derivative control were employed to study suppression of active vibration wing affected by wind airflow. Two different composite wings with different manufacturing materials had been made with specific size to be suitable for using in wind tunnel. Piezoelectric (PZT (transducers are used as sensors and actuators in vibration control systems. The velocity was 25 m/s and three different attack angles (0, 10, 20 degrees) had been taken to show their effect on the wings vibrations suppression. The results shows that the suppression of the wing amplitude is reduced when the attack angle increases for both woven and random composite wing matt and this happened due to the vortex which became more violent at the increase of attack angle and also due to the area that face the wind which will increase when the attack angle increase and this will reduces the suppression. The maximum control amplitude of woven Glass-fiber matt was 1.75cm and the damping was about 38 % at zero attack angle while it was 2cm and the damping was about 26 % at 20 degree attack angle for random Glass-fiber composite matt


Author(s):  
Hassan Bahrami ◽  
H. S. Tzou

Abstract Piezoelectric materials are increasingly being applied to various fieldS of research and engineering applications. In recent years for example, much work has been concentrated on active vibration control of structures by incorporating piezoelectric as both sensorS and actuators. In the industry, piezoelectrics are widely being accepted as effective sensors, giving engineers more leverage to add new features to their products. In this paper, piezoelectric composite structure is studied for precision placement of a multiple degrees off freedom (DOF) end–effector per the converse piezoelectric effect. This new design of the multi–DOF cantilever beam, by attaching multiple piezoelectric rectangular rods together, will provide a way to accurately position the end of this beam structure. The computation of this advanced composite structure is done by the finite element method incorporating the piezoelectric effects.


Author(s):  
A. H. Daraji ◽  
J. M. Hale

This paper concerns optimal placement of discrete piezoelectric sensors and actuators for active vibration control, using a genetic algorithm based on minimization of linear quadratic index as an objective function. A new method is developed to get state space matrices for simple and complex structures with bonded sensors and actuators, using the ANSYS finite element package taking into account piezoelectric mass, stiffness and electromechanical coupling effects. The state space matrices for smart structures are highly important in active vibration control for the optimisation of sensor and actuator locations and investigation of open and closed loop system control response, both using simulation and experimentally. As an example, a flexible flat plate with bonded sensor/actuator pairs is represented in ANSYS using three dimensional SOLID45 elements for the passive structure and SOLID5 for the piezoelectric elements, from which the necessary state space matrices are obtained. To test the results, the plate is mounted as a cantilever and two sensor/actuator pairs are located at the optimal locations. These are used to attenuate the first six modes of vibration using active vibration reduction based on a classical and optimal linear quadratic control scheme. The plate is subject to forced vibration at the first, second and third natural frequencies and represented in ANSYS using a proportional derivative controller and compared with a Matlab model based on ANSYS state space matrices using linear quadratic control. It is shown that the ANSYS state space matrices describe the system efficiently and correctly.


2019 ◽  
Vol 15 (3) ◽  
pp. 38-44
Author(s):  
Hassan Ali Kadhem ◽  
Ahmed Abdul Hussein

The first studies on shocks and vibrations were carried out at the beginning of the 1930s to improve the behavior of buildings during earthquakes. Vibration tests on aircraft were developed from 1940 to verify the resistance of parts and equipments prior to their first use. Flutter is a well-known example of dynamic aero elasticity, where when oscillation of structure interacted with unsteady aerodynamic forces the flutter will occur. Vibration on any structure without damping means that self-harmonic oscillation will occur, and in most cases the oscillation may start to increase until structural failure. This behavior is very similar to resonance phenomena if only the oscillation is being studied as a vibration case. In vibration suppression, the active vibration control is one of the more effective technique which is used for attenuating bad effects of disturbances on structure. In this work, two different composite wings have been used; one of them is made of Glass-fiber random matt and the other is made of woven ({0/90} Glass-fiber). The proportional-integral-derivative (PID) control is employed here for studying the suppression of active vibration wing affected by wind velocity flow through wind tunnel in the laboratory of mechanical engineering department at the university of Baghdad. Piezoelectric (PZT (transducers are used as sensors and actuators in vibration control systems. The attack angle was 10 degrees and three different velocities (15, 20, 35 m/s) have been taken to show their effect on the wings vibrations suppression. Is noticed that the suppression of the wing amplitude is reduced when the wind velocity increases for both woven and random composite wing matt. This is happened due to the vortex which has became more violent increase in wind velocity. It is concluded that the composite woven wing has high resistance more than the composite random wing. Also, the maximum control amplitude of woven matt is 1.9 cm and the damping is about 33% at 25 m/s wind velocity while the amplitude is 2.22 cm and the damping is about 53% at 10 m/s wind velocity for random wing.


2019 ◽  
Vol 25 (19-20) ◽  
pp. 2611-2626 ◽  
Author(s):  
Yifan Lu ◽  
Marco Amabili ◽  
Jian Wang ◽  
Fei Yang ◽  
Honghao Yue ◽  
...  

Lightweight optical mirrors usually play key roles in aerospace and optical structural systems applied to space telescopes, radars, solar collectors, communication antennas, etc. Due to their high flexibility and low damping properties, external excitations such as orbital maneuver may induce unexpected oscillations and thus reduce their working performance. Active vibration control is therefore essential for the lightweight optical mirror systems. In this spirit, a lightweight mirror structronic system with a linear quadratic optimal controller is presented. The mirror is modeled as a membrane plate with pretension and distributed polyvinylidene fluoride sensors and actuators. The sensing sensitivity of the piezoelectric (PVDF) sensors and the modal actuation factor of the PVDF actuators are derived. The state-space equations are established and the feedback control gains between sensing and control signals are obtained. Sensor and actuator of different shape, size, and position are employed to actively control the first four natural modes of the mirror. The influences of mode order, pretension, and the two weighting factors Q and R on the control performance are also investigated. Analytical results in this paper could guide the design and layout of the PZT sensor and actuator on lightweight membrane plate mirrors.


2007 ◽  
Vol 334-335 ◽  
pp. 1081-1084
Author(s):  
H.C. Yeo ◽  
N. Guo ◽  
H. Du ◽  
M. Chen

Piezoelectric bimorphs were assessed for their capabilities to be used as control actuators for vibration suppression of the print circuit boards (PCBs). Plate structures made of FR-4, a widely used industrial-grade material for manufacture of PCBs, were considered. An advanced and structured control algorithm, linear quadratic regulator with output feedback (LQROF), was used for active vibration control of the PCB structures. Experimental results showed that the LQROF control is a more robust algorithm than the classic control using the direct velocity feedback, and piezoelectric bimorph actuators present a great potential for active vibration control of the PCBs, and smart composites with embedded actuators.


2003 ◽  
Vol 03 (01) ◽  
pp. 131-141 ◽  
Author(s):  
Y. Y. LEE ◽  
K. C. LAM ◽  
K. K. YUEN ◽  
H. F. LAM ◽  
J. YAO

In this paper, the active vibration suppression of an aircraft cabin panel embedded with piezoelectric sensors and actuators under sinusoidal or random excitation is studied experimentally. The Independent Modal Space Control (IMSC) approach is employed in the controller design. The piezoelectric sensors and actuators associated with the IMSC technique have been applied to the active vibration control of the aircraft panel, and shown to be effective in vibration control. A second order controller is selected in the control scheme to suppress the fundamental modal vibration response of the aircraft cabin panel. The mode shapes of the panel are experimentally obtained, and used as the parameters of the objective functions for minimizing the unwanted vibration responses by appropriately selecting the sensor and actuator gains. Based on the experimental results, it is found that the vibration levels of the open and closed loop systems differ by up to 5.0 dB (for sinusoidal excitation) and 7.4 dB (for random excitation), even when the control circuit is interfered by electrical and magnetic noises.


Author(s):  
Brij N. Agrawal ◽  
Hyochoong Bang

Abstract The application of piezoelectric actuators and sensors in the vibration suppression of flexible structures is demonstrated experimentally. Navy Type II piezoceramic wafers were bonded at the base of a flexible arm to increase damping of its first structural mode at at 0.138 Hz. A Positive Position Feedback (PPF) analog compensator was used for active vibration control. The damping of the first mode was increased from 0.3% to 1.5 % by using the active control.


2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
A. Moutsopoulou ◽  
G. E. Stavroulakis ◽  
A. Pouliezos

Large amplitudes and attenuating vibration periods result in fatigue, instability, and poor structural performance. In light of past approaches in this field, this paper intends to discuss some innovative approaches in vibration control of intelligent structures, particularly in the case of structures with embedded piezoelectric materials. Control strategies are presented, such as the linear quadratic control theory, as well as more advanced theories, such as robust control theory. The paper presents sufficiently a recognizable advance in knowledge of active vibration control in intelligent structures.


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