Active Vibration Control Method Research Articles

Simulation Model and Method for Active Torsional Vibration Control of an HEV

Hybrid electric vehicles (HEV) might cause new noise vibration and harshness (NVH) problems, due to their complex powertrain systems. Therefore, in this paper, a new longitudinal dynamic simulation model of a series-parallel hybrid electric bus with an active torsional vibration control module is proposed. First, the schematic diagrams of the simulation model architecture and the active control strategy are given, and the dynamic models of the main components are introduced. Second, taking advantage of the characteristics of hybrid systems, a method of determining the key dynamic parameters by a bench test is proposed. Finally, in a typical bus-driving cycle for Chinese urban conditions, time domain and frequency domain processing methods are used to analyze vehicle body jerk, fluctuation of rotational speed, and torsional angle of the key components. The results show that the active control method can greatly improve the system’s torsional vibration performance when switching modes and at resonance.

Planning of works to introduce the active noise and vibration control methods for shipbuilding

The main provisions of the theory of active damping of noise and vibration are described using the adaptive suppression algorithm. Provides an overview of some successful foreign models of similar system used in various industries. Formulated the basic requirements for advanced system of active suppression, the creation of which will be in demand in shipbuilding.

Development of optimal controller design method to compensate for vibrations caused by unbalanced force in rotor system based on Nyquist diagram

In this paper, an optimal controller design method is proposed to compensate for vibrations caused by unbalanced force in the rotor system. The vibrations caused by unbalanced force are the major root cause of excessive whirling vibration in the rotor system, and it is important to compensate for the vibration to maintain its stable operation. The proposed design method can optimize a performance of the controller based on the vector locus of open loop characteristics on the Nyquist diagram. To verifiy the effectiveness, the proposed design method was employed for three typical active vibration control methods. The experimental results show that the proposed method can design the optimal parameters to compensate for the whirling vibrations of the rotor system.

Utility of probability density evolution method for experimental reliability-based active vibration control

The utility of probability density evolution method for reliability-based active vibration control of a cantilevered flexible beam is experimentally investigated. In this respect, an optimal linear quadratic regulator (LQR) is utilized together with an observer to design an online full-state feedback controller. In order to design a well-performing controller and to simulate the controller performance, a system model is obtained via identification techniques. Reliability tests are consequently performed to verify the effectiveness of the presented reliability assessment method as a foundation for reliability-based control. Subsequently, a hybrid metaheuristic optimization scheme of continuous ant colony system is used for simultaneous integrated tuning of the LQR and observer parameters through all processes. Optimization of the controller and the observer is performed with the objective of system structural reliability. An optimized version of classical LQR controller is also developed for making comparisons between the two control methods. Finally, a comparison is made between the mean power consumption of the 2 controllers. It is realized that the reliability-based controller decreases operating costs without compromising system safety.

A Low-Cost Lateral Active Suspension System of the High-Speed Train for Ride Quality Based on the Resonant Control Method

This paper focuses on the low-cost configuration of the lateral active suspension system for the high-speed train. First, the full-scale railway vehicle dynamics with 17-degree-of-freedom are introduced, where the actuator saturation, suspension deflection, and random and periodic track irregularities are considered. Then, based on the internal model principle, some classic active vibration control methods, e.g., the PID, positive position feedback, repetitive, and resonant controls, are unified as an internal model (IM)-based form and an IM-based resonant control is further presented. After that, to suppress various vibrations, three principles are presented to set the damping ratio and natural frequency of the IM-based resonant controller according to the properties of the controlled plant and/or the external disturbances. In consequence, an active suspension with the IM-based resonant controller is designed to improve the ride quality of the high-speed train, where the $H_{\infty }$ method is used to calculate the unique gain. Moreover, the configuration of the active suspension is low cost and consists of two independent control systems, where one control system only has a pair of actuators and an accelerometer. Finally, the random and periodic track irregularities are employed to show the efficiency of the proposed resonant-control-based active suspension by comparing with the linear quadratic Gaussian (LQG) and $H_{\infty }$ controllers.

Nonprobabilistic Reliable LQR Design Method for Active Vibration Control of Structures with Uncertainties

The linear quadratic regulator (LQR), which allows a natural consideration of the constraints on state variables and control effort, is widely used in modern control theory for the active control of structural vibration. However, uncertainties are unavoidable in the design of active control systems. Thus, in the design process of an LQR controller, it is important to deal with these uncertainties, which are always bounded and have a great influence on the final performance of the closed-loop system. In this paper, the nonprobabilistic reliability concept is extended to the selection of weighting matrices for determining the LQR controller. First, a new uncertainty propagation analysis method for an active control system is presented. To adapt to the special problem of controller design, a novel nonprobabilistic reliability index is proposed. The reliability and safety margin of the closed-loop system can be continuously characterized by this modified nonprobabilistic reliability index. The weighing matrices used to design the LQR controller via the Riccati equation are finally determined by solving a reliability-based optimization problem. The proposed method preserves the excellent characteristics of LQR control theory and provides a quantitative method for selecting the weight matrices for LQR controller design in consideration of the inherent uncertainties. Two numerical examples are presented to demonstrate the effectiveness and feasibility of the proposed method. The results from these examples reveal that the uncertainties in active control system design can be addressed from a reliability perspective.

Active Vibration Control using Air Spring

In the present study, a novel method of active vibration control of machines subject to base excitation using air spring is proposed. The study also includes proposes of a feedback control system, for active vibration control with mass flow rate as a function of the velocity of the mass, and/or base of air spring. Earlier study shows application of air spring as a force actuator. The mass flow introduces additional input excitation into the system by means of which the stiffness or resultant excitation force on the mass can be changed. A mathematical model is developed and response to steady state and transient base input are obtained. The use of appropriate value of gain in the system can ensure that the amplitude of response to excitation from the base is lower than the amplitude of base excitation. Some suitable values of gain depending on the special cases considered are suggested. An active control system with mass flow rate as a function of base velocity and gain equal to − 1 is most effective in controlling the vibration. This is highly desirable in case of high precision equipment. The interesting observation is that the spring rate can be changed and even made negative.

A Time‐Domain Active Vibration Control Algorithm for Helicopter Based on a Prior Error Channel Identification Strategy

During the flight tests of Z‐11 helicopter, the previous method for active vibration control of helicopter suffered from the problems of slow convergence speed and big residual vibration. In order to mitigate these problems, a new method was proposed on the basis of the previous one. Here, a new error channel modeling method is used, which is named the prior error channel identification strategy. And the active control process and the error channel identification process are simplified to improve performance of the system. Besides, the complexity of the method is reduced. Active vibration control simulations were performed based on a simplified model of helicopter fuselage. The simulation results show that the proposed method has lower residual vibration, faster convergence speed, and better capacity for resisting disturbance compared with the previous method. Finally, an active control of structure response experiment was conducted on a free‐free beam, and good inhibitory effect of the vibration response of the free‐free beam was obtained. The results illustrate that the proposed method based on the prior error channel identification strategy is effective.

A method for bidirectional active vibration control of structure using discrete-time sliding mode

In this paper, a novel discrete-time sliding mode control is proposed in order to attenuate structural vibration due to earthquake forces. The analysis is based on the lateral-torsional vibration under the bidirectional waves. The proposed fuzzy modeling based sliding mode control can reduce chattering due to its time-varying gain. In the modeling equation of the structural system, the uncertainty exists in terms of sti¤ness, damping forces and earthquake. Fuzzy logic model is used to identify and compensate the uncertainty associated with the modeling equation. We prove that the closed-loop system is uniformly stable using Lyapunov stability analysis. The experimental result reveals that discrete-time sliding mode controller offers significant vibration attenuation with active mass damper and torsional actuator.

Active Vibration Control of Composite Pyramidal Lattice Truss Core Sandwich Plates

AbstractThe vibration characteristics of composite pyramidal truss core sandwich plates with piezoelectric actuator/sensor pairs were investigated, and the active vibration control methods of the s...

Self-Sensing Electromagnetic Transducer for Vibration Control of Space Antenna Reflector

Space antenna reflectors are used by space vehicles to communicate with ground stations. These reflectors are generally subject to broadband random vibration and shock conditions during shipment and vehicle launch. While active vibration control methods can reduce any unexpected responses, sensors, controllers, power amplifiers, and actuators are all required to implement the control system. These additional external devices increase both the weight and the cost of the reflector, and reduce the reliability and safety of the space product. This study proposes a novel self-sensing vibration control method and applies a self-sensing electromagnetic transducer to suppress the vibration of a space antenna reflector. This transducer is used bifunctionally, acting as both an isolator and a velocity sensor. The vibration control principle of the proposed method is analyzed. A governing equation is established using the finite element method. A type of degree of freedom reduction method is used to obtain the response of the space antenna reflector. A ground experiment is then set up. The results demonstrate that the proposed self-sensing vibration control method can reduce the second-order and third-order vibrations of the space antenna reflector by 4 and 9 dB, respectively.

Comparative analysis and exprimental results of advanced control strategies for vibration suppression in aircraft wings

The smart beam is widely used as a means of studying the dynamics and active vibration suppression possibilities in aircraft wings. The advantages obtained through this approach are numerous, among them being aircraft stability and manoeuvrability, turbulence immunity, passenger safety and reduced fatigue damage. The paper presents the tuning of two controllers: Linear Quadratic Regulator and Fractional Order Proportional Derivative controller. The active vibration control methods were tested on a smart beam, vibrations being mitigated through piezoelectric patches. The obtained experimental results are compared in terms of settling time and control effort, experimentally proving that both types of controllers can be successfully used to reduce oscillations. The analysis in this paper provides for a necessary premise regarding the tuning of a fractional order enhanced Linear Quadratic Regulator, by combining the advantages of both control strategies.

Reducing Blanking Vibration with Active Vibration Control Using a Servo Press

Blanking noise and blanking vibration are causes of pollution. At the same time, blanking vibration disturbs the high precision of a press work product, and shortens the life expectancy of the press machine and the press die. Recently, the use of a servo press has been developed to improve these problems, using low speed blanking and pulse vibration banking. However, these methods lengthen the blanking time, so it is necessary to control the servo press properly in the case of blanking. In this study, we describe a principle for the reduction of blanking vibration when using a servo press, and we propose an active vibration control method for the reduction of blanking vibration. We used a crank servo press of 450kN in an experiment, which has a pulse motion of 10Hz. We conducted a simulation and an experiment of blanking using an active vibration control method, which we named “counter pulse blanking.” We confirmed that counter pulse blanking is effective in reducing vibration as a result of the simulation and the experiment.

Robust control in rotating machinery using linear matrix inequalities

Some active vibration control methods are based on mathematical models. In these cases, parameter variations play an important role in the system performance. As it is not possible to know in advance the precise values for all parameters of the mechanical system, a possible alternative is to design robust controllers that take into account the uncertainties. In this context, this work presents a vibration active control technique devoted to rotating machinery by incorporating electromagnetic actuators, which considers uncertainties in the parameters of the system. the gains of the electromagnetic actuator are determined by using linear matrix inequalities, which consist in a powerful tool for the cases in which parameter uncertainties are taken into account. In addition, Kalman estimators are employed to deduce the modal states of the system. The model of the rotating system is obtained by using the finite element method and the potentiality of the methodology for applications in engineering was investigated through experimental tests.

A Study of H infinity and H2 synthesis for Active Vibration Control

Abstract Minimization of car vibrations has been a topic of research over the years and many control strategies have been developed. Therefore, there needs to be a method for active vibration control in cars. This paper presents two methods for designing the controller for a quarter car model which would help in minimizing car vibrations and increasing passenger comfort subjected to road disturbances. The methodologies used are H-infinity and H-2 optimal control. The main aim of this article is to design a controller to control the response of a quarter car model to various road inputs. This is a non-linear model with 2 degrees of freedom. It is linearized and modelled as a disturbance rejection (regulatory) problem wherein the effect of disturbances are minimised. Different weighing functions have been considered to take the impact of road disturbances into account. The results are compared with the Proportional Integral Derivative (PID) controller designed using the same system parameters and performance specifications. The behaviour of the open loop and closed loop system is observed by examining the impulse and frequency responses in MATLAB. A detailed discussion is done with the choice of weighing functions. It is found that the disturbance rejection techniques suggested in this paper help in improving the system response

Identification for Active Vibration Control of Flexible Structure Based on Prony Algorithm

Flexible structures have been widely used in many fields due to the advantages of light quality, small damping, and strong flexibility. However, flexible structures exhibit the vibration in the process of manipulation, which reduces the pointing precision of the system and causes fatigue of the machine. So, this paper focuses on the identification method for active vibration control of flexible structure. The modal parameters and transfer function of the system are identified from the step response signal based on Prony algorithm, while the vibration is attenuated by using the input shaping technique designed according to the parameters identified from the Prony algorithm. Eventually, the proposed approach is applied to the most common flexible structure, a piezoelectric cantilever beam actuated by Macro Fiber Composite (MFC). The experimental results demonstrate that the Prony algorithm is very effective and accurate on the dynamic modeling of flexible structure and input shaper could significantly reduce the vibration and improve the response speed of system.

Active Vibration Control for a Large Annular Flexible Structure via a Macro-Fiber Composite Strain Sensor and Voice Coil Actuator

Large annular flexible structures (LAFS) are typical antenna structures for satellites. This structure can significantly increase antenna aperture and effectively improve communication accuracy with minimum addition of mass. LAFS have become mainstream for large aperture antenna structures. However, they have disadvantages, such as low natural frequencies, low damping ratio, and low stiffness. They easily suffer from low frequency, longtime and modal responses. Therefore, the vibration control of LAFS is very important. This study proposes a novel active vibration control method using macro-fiber composite (MFC) as a sensing unit, a voice coil actuator and a PD-fuzzy control algorithm. The MFC sensor can measure a minimum strain of 10-8 m/m. The voice coil actuator generates a displacement and driving force. Based on the feedback signal from the MFC sensor, the PD-fuzzy control algorithm controls the voice coil actuator. A dynamic model of LAFS was established, and its characteristics analyzed. A theoretical model for the voice coil actuator and MFC sensor were established, and the corresponding governing equations derived. An experimental system was set up. The results demonstrated that the novel active vibration control method has good performance. This active vibration control method can control vibration at ultralow frequencies and requires no additional stiffness.

Optimal integral force feedback for active vibration control

This paper proposes an improvement to Integral Force Feedback (IFF), which is a popular method for active vibration control of structures and mechanical systems. Benefits of IFF include robustness, guaranteed stability and simplicity. However, the maximum damping performance is dependent on the stiffness of the system; hence, some systems cannot be adequately controlled. In this paper, an improvement to the classical force feedback control scheme is proposed. The improved method achieves arbitrary damping for any mechanical system by introducing a feed-through term. The proposed improvement is experimentally demonstrated by actively damping an objective lens assembly for a high-speed confocal microscope.

Active linear quadratic Gaussian control of the vibration of a flexible beam with a time-varying mass

A linear quadratic Gaussian method for active vibration control of a flexible beam with a time-varying mass is studied in this article. As the time-varying mass can change the resonance frequencies of system and induce instability of system, the vibration control of time-varying mass systems using piezoelectric actuators has been the subject of recent interest. The equation of motion of a beam with a time-varying concentrated mass is obtained by using admissible functions and the principle of separation of variables. Then, active control using piezoelectric actuators is simulated for the time-varying mass system. The linear quadratic Gaussian control strategy is employed for the suppression of transverse vibration of the beam with time-varying mass under different conditions. The numerical results show that the proposed scheme can attenuate the vibration of the variable mass system effectively in the interested frequency range. The control method can be used for the beam with constant mass or time-varying mass.

B201 磁気浮上を用いた制震装置の開発(OS7 磁気浮上・磁気軸受の制御1)

This study expresses a novel active vibration control method for a house structure by using magnetic levitation. The magnetic levitation system is easy to install to the ceiling because there is no need to use linear guides or bearings. In this study, a magnetic levitation device is attached to the iron plate fixed firmly to ceiling of the structure and it will levitate when a vibration occurs. The total mass of structure will be decreased while levitating, resulting in the change of its natural frequency. Moreover, an efficient vibration control method is examined. Finally the results of experiments are shown to confirm its feasibility.