Active Vibration Control of the Axially Moving String Using Space Feedforward and Feedback Controllers

1996 ◽  
Vol 118 (3) ◽  
pp. 306-312 ◽  
Author(s):  
S. Ying ◽  
C. A. Tan
Keyword(s):  
Vibration Control ◽  
Feedforward Control ◽  
Active Vibration Control ◽  
Upstream Region ◽  
Control Force ◽  
Feedback Controllers ◽  
Axially Moving String ◽  
Downstream Region ◽  
Active Vibration ◽  
Axially Moving

Active vibration control of an axially moving string using space feedforward and feedback controllers is presented. Closed-form results for the transverse response of both the uncontrolled and controlled string are given in the s domain. The space feedforward controller is established by employing the idea of wave cancellation. The proposed control law indicates that vibration in the region downstream of the control force can be cancelled. With the space feedforward control, the mode shapes of the axially moving string are changed such that the free response tends to zero in the downstream region. An interesting physical interpretation is that the control force acts effectively as a holder (active support) which limits the vibration of the string to the upstream region and eliminates any vibration in the downstream region. Simulation results show that the response of the string to both sinusoidal and random excitations is suppressed by applying the space feedforward control. The feedback controller is introduced to attenuate the response of the string due to undesired disturbances in the downstream.

Active Vibration Control of the Axially Moving String by Wave Cancellation

1993 ◽  
Author(s):  
C. H. Chung ◽  
C. A. Tan
Keyword(s):  
Vibration Control ◽  
Active Vibration Control ◽  
Closed Form Expression ◽  
Control Law ◽  
Closed Loop System ◽  
Controlled System ◽  
Axially Moving String ◽  
Active Vibration ◽  
Axially Moving ◽  
Actuation Devices

Abstract Active vibration control of an axially moving string by wave cancellation is presented. The control problem is formulated in the frequency domain. An exact, closed-form expression for the transfer function of the closed-loop system, consisting of the flexible structure, a feedback control law and the dynamics of the sensing and actuation devices, is derived. It is shown that all vibration modes can be stabilized and that the controlled system has no resonance. Moreover, the designed controller is applicable to the control of the string transverse vibration under various kinds of loading and constraint conditions. Results for the response of the controlled string under different excitations are presented and discussed along with the wave propagation and cancellation characteristics.

Active Vibration Control of the Axially Moving String in the S Domain

1991 ◽  
Vol 58 (1) ◽  
pp. 189-196 ◽  
Author(s):  
B. Yang ◽  
C. D. Mote
Keyword(s):  
Vibration Control ◽  
Controller Design ◽  
Active Vibration Control ◽  
Stabilizing Controller ◽  
Axially Moving String ◽  
The Laplace Transform ◽  
Modes Of Vibration ◽  
Active Vibration ◽  
Axially Moving ◽  
Actuation Devices

A new method is presented for active vibration control of the axially moving string, one of the most common models of axially moving continua. The control is formulated in the Laplace transform domain. The transfer function of a closed-loop system, consisting of the plant, a feedback control law and the dynamics of the sensing and actuation devices, is derived. Analysis of the root loci of the closedloop system gives two stability criteria. Stabilizing controller design is carried out of both collocation and noncollocation of the sensor and actuator. It is found that all the modes of vibration can be stabilized and that in principle the spillover instability can be avoided. Also, the steady-state response of the stabilized string to periodic, external excitation is presented in closed form.

Active Vibration Control of the Axially Moving String by Wave Cancellation

1995 ◽  
Vol 117 (1) ◽  
pp. 49-55 ◽  
Author(s):  
C. H. Chung ◽  
C. A. Tan
Keyword(s):  
Vibration Control ◽  
Active Vibration Control ◽  
Closed Form Expression ◽  
Control Law ◽  
Vibration Modes ◽  
Controlled System ◽  
Axially Moving String ◽  
Active Vibration ◽  
Axially Moving ◽  
Actuation Devices

Active vibration control of an axially moving string by wave cancellation is presented. The control problem is formulated in the frequency domain. An exact, closed-form expression for the transfer function of the controlled system, consisting of the flexible structure, a feedback control law and the dynamics of the sensing and actuation devices, is derived. It is shown that all vibration modes can be stabilized and that the controlled system has no resonance. Moreover, the designed controller is applicable to the control of the string transverse vibration under various kinds of loading and constraint conditions. Results for the response of the controlled string under different excitations are presented and discussed along with the wave propagation and cancellation characteristics.

Boundary Control of an Axially Moving String Via Lyapunov Method

1999 ◽  
Vol 121 (1) ◽  
pp. 105-110 ◽  
Author(s):  
Rong-Fong Fung ◽  
Chun-Chang Tseng
Keyword(s):  
Boundary Control ◽  
Lyapunov Method ◽  
Sliding Mode ◽  
Semigroup Theory ◽  
Active Vibration Control ◽  
Nonlinear Partial Differential Equation ◽  
Distributed Parameter ◽  
Axially Moving String ◽  
Active Vibration ◽  
Axially Moving

This paper presents the active vibration control of an axially moving string system through a mass-damper-spring (MDS) controller at its right-hand side (RHS) boundary. A nonlinear partial differential equation (PDE) describes a distributed parameter system (DPS) and directly selected as the object to be controlled. A new boundary control law is designed by sliding mode associated with Lyapunov method. It is shown that the boundary feedback states only include the displacement, velocity, and slope of the string at RHS boundary. Asymptotical stability of the control system is proved by the semigroup theory. Finally, finite difference scheme is used to validate the theoretical results.

Active Vibration Control of a Triple Flexible Structures Combined With Actuators

1995 ◽  
Author(s):  
Kazuto Seto ◽  
Yoshihiro Toba ◽  
Fumio Doi
Keyword(s):  
Vibration Control ◽  
Large Scale ◽  
Active Vibration Control ◽  
Flexible Structures ◽  
Low Frequency ◽  
Tall Buildings ◽  
Control Force ◽  
Active Vibration ◽  
Strong Winds ◽  
Lq Control

Abstract In order to realize living comfort of tall buildings by reducing the vibration of higher floors by strong winds, this paper proposes a new method of vibration control for flexible structures with a large scale. The higher a tall building the lower its natural frequency. Since obtaining sufficient force to control the lower frequency vibrations of tall buildings is a difficult task, controlling the vibration of ultra-tall buildings using active dynamic absorbers is nearly impossible. This problem can be overcome by placing actuators between a pair of two or three ultra-tall buildings and using the vibrational force of each building to offset the vibrational movement of its paired mate. Therefore, it is able to obtain enough control force under the low frequency when the proposed method is used. In this paper, a reduced-order model expressed by 2DOF system under taking into consideration for preventing spillover instability is applied to control each flexible structure. The LQ control theory is applied to the design of such a control system. The effectiveness of this method is demonstrated theoretically as well as experimentally.

scholarly journals A Comparative Study Based on Different Control Algorithms for Suppressing Multistage Gear Transmission System Vibrations

2018 ◽  
Vol 2018 ◽  
pp. 1-16
Author(s):  
Wenhao Sun ◽  
Feng Zhang ◽  
Weidong Zhu ◽  
Han Wang ◽  
Shunan Luo ◽  
...  
Keyword(s):  
Vibration Control ◽  
Active Vibration Control ◽  
Transmission System ◽  
Gear Transmission ◽  
Control Algorithms ◽  
Control Force ◽  
The Finite Element Method ◽  
Control Schemes ◽  
Gear Transmission System ◽  
Active Vibration

A modal analysis (MA) was preconsidered to determine a novel active vibration control (AVC) structure of multistage gear transmission system (MGTS) and an appropriate actuating position for the piezoelectric actuator (PZT); the results of the calculating method and the finite element method (FEM) were compared to validate the reliability of MA. The controllers based on different control algorithms were designed to drive the PZTs to output the control force for suppressing the host structure vibrations. To analyze the feasibility of the applied control schemes and discuss the control effects dominated by the different control algorithms, a series of active vibration control numerical simulations were studied. The cosimulation results validate the practicability of the proposed control schemes and provide a forcible guidance for the further experimental works.

scholarly journals Active Vibration Control of Rib Stiffened Plate by Using Decentralized Velocity Feedback Controllers with Inertial Actuators

2019 ◽  
Vol 9 (15) ◽  
pp. 3188 ◽  
Author(s):  
Xiyue Ma ◽  
Lei Wang ◽  
Jian Xu
Keyword(s):  
Vibration Control ◽  
Active Vibration Control ◽  
Low Frequency ◽  
Good Control ◽  
Practical Significance ◽  
Stiffened Plate ◽  
Control Performance ◽  
Feedback Controllers ◽  
Velocity Feedback ◽  
Active Vibration

Active control of low frequency vibration and sound radiation from a rib stiffened plate has great practical significance as this structure is widely applied in engineering, such as aircraft or ship fuselage shells. This paper presents an investigation on the performance of active vibration control of the rib stiffened plate by using decentralized velocity feedback controllers with inertial actuators. A simple modeling approach in frequency domain is proposed in this research to calculate the control performance. The theoretical model of vibrating response of the ribbed plate and the velocity feedback controllers is first established. Then, as an important part, the influences of the control gain and the number of the decentralized unit on the control performance are investigated. Results obtained demonstrate that—similar to that of the unribbed plate case—appropriately choosing the number of the unit and their feedback gains can achieve good control results. Too many units or very high feedback gains will not bring further noise reduction.

Active Control of Rotor Vibrations by Two Feedforward Control Algorithms

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Kari Tammi
Keyword(s):  
Vibration Control ◽  
Feedforward Control ◽  
Active Vibration Control ◽  
Fir Filter ◽  
Lms Algorithm ◽  
Control Methods ◽  
Rotor Vibration ◽  
Operating Range ◽  
Active Vibration ◽  
Adaptive Fir

Resonance vibrations (critical speeds) play a significant role in rotor vibration control. Active vibration control methods for rotors are studied to develop solutions to enhance machines’ dynamic behavior, durability, and operating range. This paper reports rotor vibration attenuation with a supplementary electromagnetic actuator located outside the rotor bearing span. Feedback and feedforward control system design are shown, and comparative experiments on two active vibration control methods for mass unbalance compensation are reported. The methods compared are adaptive FIR filter with the least mean squares (LMS) algorithm and convergent control (CC) method with a frequency-domain adaptation algorithm. The methods were experimentally validated on the rotor test rig (rotor weight 2.7 kg, length 560 mm, and first critical speed about 50 Hz). The feedback system provided wideband damping in the sub- and supercritical regions. The feedforward systems attenuated vibratory responses at the speed of rotation and its harmonic. The attenuation achieved was about 20 dB depending on the rotor speed. Also, discrete-time CC algorithm is shown to have a feedback equivalent circuit. The significance of feedback control lies in making the system phase-characteristics sufficiently smooth for feedforward control methods. Then, feedforward algorithms provided a good vibration damping performance over the operating range. CC was found to be a more effective and simpler algorithm for the purpose than the adaptive FIR filter with the LMS algorithm. The equivalent feedback circuit derived for CC, and systems similar to CC, facilitates their stability and robustness analysis.

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