Semi-active vibration control of space truss structures by friction damper for maximization of modal damping ratio

2013 ◽  
Vol 332 (20) ◽  
pp. 4817-4828 ◽  
Author(s):  
Young-min Park ◽  
Kwang-joon Kim
Keyword(s):  
Vibration Control ◽  
Damping Ratio ◽  
Active Vibration Control ◽  
Truss Structures ◽  
Friction Damper ◽  
Space Truss ◽  
Modal Damping Ratio ◽  
Modal Damping ◽  
Active Vibration

Active Vibration Control of Epoxy Matrix Composite Beams with Embedded Shape Memory Alloy TiNi Fibers

2003 ◽  
Vol 17 (08n09) ◽  
pp. 1744-1749 ◽  
Author(s):  
T. Aoki ◽  
A. Shimamoto
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Vibration Control ◽  
Matrix Composite ◽  
Epoxy Matrix ◽  
Damping Ratio ◽  
Active Vibration Control ◽  
Composite Beams ◽  
Epoxy Matrix Composite ◽  
Active Vibration

In this paper, epoxy matrix composite beams with embedded TiNi (SMA: Shape Memory Alloy) fiber are applied to enhance the strength and fracture toughness of the machinery components. It is also well known that SMA shows the remarkable changes of stiffness and damping ratio between martensite at lower temperature and austenite at high temperature. A shape recovery force is associated with inverse phase transformation of SMA. The effects of heating with current and pre-strain in TiNi fiber of SMA on vibration characteristics are experimentally investigated. The active vibration control is achieved by controlling the current and pre-strain.

scholarly journals Experimental Active Vibration Control in Truss Structures Considering Uncertainties in System Parameters

2008 ◽  
Vol 2008 ◽  
pp. 1-14 ◽  
Author(s):  
Douglas Domingues Bueno ◽  
Clayton Rodrigo Marqui ◽  
Rodrigo Borges Santos ◽  
Camilo Mesquita Neto ◽  
Vicente Lopes
Keyword(s):  
Vibration Control ◽  
Dynamic Model ◽  
Electromechanical Coupling ◽  
Active Vibration Control ◽  
Experimental Methodology ◽  
Truss Structures ◽  
Linear Matrix ◽  
System Parameters ◽  
Identification Method ◽  
Active Vibration

This paper deals with the study of algorithms for robust active vibration control in flexible structures considering uncertainties in system parameters. It became an area of enormous interest, mainly due to the countless demands of optimal performance in mechanical systems as aircraft, aerospace, and automotive structures. An important and difficult problem for designing active vibration control is to get a representative dynamic model. Generally, this model can be obtained using finite element method (FEM) or an identification method using experimental data. Actuators and sensors may affect the dynamics properties of the structure, for instance, electromechanical coupling of piezoelectric material must be considered in FEM formulation for flexible and lightly damping structure. The nonlinearities and uncertainties involved in these structures make it a difficult task, mainly for complex structures as spatial truss structures. On the other hand, by using an identification method, it is possible to obtain the dynamic model represented through a state space realization considering this coupling. This paper proposes an experimental methodology for vibration control in a 3D truss structure using PZT wafer stacks and a robust control algorithm solved by linear matrix inequalities.

scholarly journals Active Piezoelectric Vibration Control of Subscale Composite Fan Blades

2012 ◽  
Author(s):  
Kirsten P. Duffy ◽  
Benjamin B. Choi ◽  
Andrew J. Provenza ◽  
James B. Min ◽  
Nicholas Kray
Keyword(s):  
Vibration Control ◽  
Electromechanical Coupling ◽  
New Technologies ◽  
Piezoelectric Materials ◽  
Fiber Composite ◽  
Damping Ratio ◽  
Active Vibration Control ◽  
Rotor Speed ◽  
Blade Vibration ◽  
Active Vibration

As part of the Fundamental Aeronautics program, researchers at NASA Glenn Research Center (GRC) are investigating new technologies supporting the development of lighter, quieter, and more efficient fans for turbomachinery applications. High performance fan blades designed to achieve such goals will be subjected to higher levels of aerodynamic excitations which could lead to more serious and complex vibration problems. Piezoelectric materials have been proposed as a means of decreasing engine blade vibration either through a passive damping scheme, or as part of an active vibration control system. For polymer matrix fiber composite blades, the piezoelectric elements could be embedded within the blade material, protecting the brittle piezoceramic material from the airflow and from debris. To investigate this idea, spin testing was performed on two General Electric Aviation (GE) subscale composite fan blades in the NASA GRC Dynamic Spin Rig Facility. The first bending mode (1B) was targeted for vibration control. Because these subscale blades are very thin, the piezoelectric material was surface-mounted on the blades. Three thin piezoelectric patches were applied to each blade — two actuator patches and one small sensor patch. These flexible macro-fiber-composite patches were placed in a location of high resonant strain for the 1B mode. The blades were tested up to 5000 rpm, with patches used as sensors, as excitation for the blade, and as part of open- and closed-loop vibration control. Results show that with a single actuator patch, active vibration control causes the damping ratio to increase from a baseline of 0.3% critical damping to about 1.0% damping at 0 RPM. As the rotor speed approaches 5000 RPM, the actively controlled blade damping ratio decreases to about 0.5% damping. This occurs primarily because of centrifugal blade stiffening, and can be observed by the decrease in the generalized electromechanical coupling with rotor speed.

The Design and Application of Piezoelectric Friction Damper with Self-Powered and Sensing Control System

2010 ◽  
Vol 163-167 ◽  
pp. 2477-2481
Author(s):  
Na Xin Dai ◽  
Ping Tan ◽  
Fu Lin Zhou
Keyword(s):  
Control System ◽  
Vibration Control ◽  
Active Control ◽  
Mechanical Energy ◽  
Active Vibration Control ◽  
Friction Damper ◽  
Active Vibration ◽  
Self Powered ◽  
Control Equation ◽  
Converse Piezoelectric Effect

To make the active and semi-active vibration control system in civil engineering get rid of external power supply, a new piezoelectric friction damper with self-power and sensing is designed in this paper and a semi-active control system based on this damper is presented. This system includes three key parts: a piezoelectric friction damper, a power generator based on the piezoelectric stack electro-mechanical energy conversion and a control circuit. It makes full use of the direct and converse piezoelectric effect. At the same time, it also overcomes the deficiency that the frictional force as damping can not be accurately desired in semi-active vibration control system. On the basis of it, the control equation of PFD is formulated. Numerical simulations for seismic protection of story isolation equipped with this system excited by a historical earthquake are conducted by MATLAB. Skyhook control is used to command a piezoelectric friction damper in the semi-active control. It is noticed that only one accelerometer is needed to monitor the response to realize the skyhook control, which greatly simplifies the classical semi-active vibration control system.

Optimal Research of Actuator Placement for Piezoelectric Smart Structure

2009 ◽  
Vol 419-420 ◽  
pp. 173-176
Author(s):  
Wei Yuan Wang ◽  
Kai Xue ◽  
Dong Yan Shi
Keyword(s):  
Vibration Control ◽  
Control Method ◽  
Active Vibration Control ◽  
Element Model ◽  
Smart Structure ◽  
Optimal Placement ◽  
Optimal Method ◽  
Modal Damping ◽  
Active Vibration ◽  
Modal Space

The purpose of this paper is to investigate the optimal placement of piezoelectric actuator for active vibration control of smart structure. The structures can be described in the modal space based on the independent modal space control method and dynamic equations derived from finite element model. The modal damping ratios are derived from modal equations and an optimal target is given by maximizing the modal damping ratios. Accumulation method is adopted to the optimization calculation. Simulations are carried out for active vibration control of a conical shell with distributed piezoelectric actuators. Control effects proved the validity of the optimal method above by compared with the non-optimal results. The optimal method in this paper gives a useful guide for quantity optimization of actuators to piezoelectric structures.

Active Vibration Control of a Space Truss Using PZT Stack Actuator

1999 ◽  
Author(s):  
Gangbing Song ◽  
John Vlattas ◽  
Scott E. Johnson ◽  
Brij N. Agrawal
Keyword(s):  
Vibration Control ◽  
Piezoelectric Ceramic ◽  
Proof Mass ◽  
Active Vibration Control ◽  
Force Transducer ◽  
Experimental Results ◽  
Naval Postgraduate School ◽  
Double Integral ◽  
Space Truss ◽  
Active Vibration

Abstract This paper presents design, implementation and experimental results of active vibration control of Naval Postgraduate School (NPS) Space Truss using a piezoelectric ceramic stack actuator. The NPS space truss represents a flexible spacecraft structure which may support interferometer, antenna, and other vibration-sensitive instrumentation. To simulate the effects of a spacecraft disturbance on the truss, a proof mass actuator is incorporated on the structure to excite the truss. To reduce the vibrations caused by the proof mass actuator, an active strut member is installed along a diagonal of the base bay of the truss. The active strut element consists of a piezoelectric ceramic actuator stack, a force transducer, and mechanical interfaces. An integral plus double-integral force controller is designed to suppress vibration of the truss. Experimental results demonstrate that the active piezoceramic strut actuator can effective reduce truss vibration.

Calculation on Modal Damping Ratio of Stay Cable Using Nonlinear Friction Damper

2012 ◽  
Vol 538-541 ◽  
pp. 1800-1803
Author(s):  
Hui Ping Wang
Keyword(s):  
Damping Ratio ◽  
Free Vibrations ◽  
Nonlinear Friction ◽  
Friction Damper ◽  
Stay Cable ◽  
Lumped Mass ◽  
Mass Model ◽  
Modal Damping Ratio ◽  
Stay Cables ◽  
Modal Damping

Stay cables of long span cable-stayed bridges are easy to vibrate under wind or wind/rain loads owning to their very low inherent damping. To install cable dampers near to the anchorages of cable has become a common practice for cable vibration control of cable-stayed bridge structures. In this study, the behaviors of a nonlinear frictional type of damper were investigated. The equations of motion of a cable with a friction damper were derived by using a lumped mass model. Then by introducing modal transformation, the analytical solution for the motion equations was obtained. The results show that the friction damper evokes linearly decaying of free vibrations of the cable as long as the damper does not lock the cable. The modal damping ratio of cable with the friction damper is strongly amplitude dependent. Calculation of modal damping ratio can be simplified using control parameter and the maximum modal damping ratio can be obtained. A universal estimation curve is proposed that is similar to linear viscous damper. These studies could provide design basis for the vibration mitigation of stay cables using nonlinear friction.

scholarly journals Optimization of VEDs for Vibration Control of Transmission Line Tower

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Guoping Huang ◽  
Jianhua Hu ◽  
Yuzhu He ◽  
Haibo Liu ◽  
Xiugui Sun
Keyword(s):  
Transmission Line ◽  
Vibration Control ◽  
Damping Ratio ◽  
Element Model ◽  
Control Performance ◽  
Bending Vibration ◽  
Viscoelastic Dampers ◽  
Modal Damping Ratio ◽  
Modal Damping ◽  
The Finite Element Model

This paper investigates the optimization of viscoelastic dampers (VEDs) for vibration control of a transmission line tower. Considering the stiffness of the steel brace connected to a VED, the mechanical model of the VED-brace system was established. Subsequently, the additional modal damping ratio of the transmission line tower attached with VEDs was obtained analytically. Furthermore, the finite element model of a two-circuit transmission line tower with VEDs was built in ANSYS software, and the influences of installation positions and parameters of VEDs on the additional modal damping ratio were clarified. In addition, the control performance of VEDs on the transmission line tower subjected to wind excitations was emphatically illustrated. The results show that the stiffness of the steel brace connected to a VED has a significant effect on the maximum additional modal damping ratio of the VED-brace system provided for the transmission line tower and the optimal parameters of the VED. Meanwhile, the installation positions of VEDs dramatically influence the additional modal damping ratio. Moreover, the increase of the brace stiffness and the loss factor is beneficial to improve the control performance of VEDs. Besides that, the VEDs present superior control performance on the top displacement of the transmission line tower as well as the transverse bending vibration energy.

Sign in / Sign up

Export Citation Format

Share Document