Lateral Vibration Control Research Articles

Lateral Vibration Control Strategy of High-Speed Elevator Car Based on Sparrow Search Optimization Algorithm

Aiming at the problems of inefficient mitigation of the lateral vibration of high-speed elevator cars, which results in low riding comfort, this paper introduces the electromagnetic active rolling guide shoes and incorporates the sky-hook damping control strategy into the high-speed elevator structure. On this basis, it adopts an optimization algorithm based on Sparrow Search Algorithm (SSA) to adjust the parameters of the lateral vibration controller, thereby reducing the amplitude of the lateral vibration and controlling it within the human comfort range. Specifically, this paper first incorporates electromagnetic active rolling guide shoes into the vibration reduction device of the high-speed elevator car. Based on the motion characteristics of lateral vibration, a mathematical model is established in which the sky-hook damping control strategy is introduced. Then, a simulation model is built, and the damping parameters of the controller are optimized using the SSA, resulting in effective control of the lateral vibration amplitude of the high-speed elevator car. Simulations demonstrate that the lateral vibration control model of the high-speed elevator car, optimized by SSA, achieves lower amplitudes within the frequency range of 1–2 Hz compared to the results obtained by the Genetic Algorithm (GA), demonstrating the effectiveness of SSA in optimizing the damping parameters of the car controller. Finally, the simulation results are compared with the measured data, and the research findings indicate that the proposed method for lateral vibration control of the car can effectively suppress the lateral vibration amplitude.

Bogie active stability simulation and scale rig test based on frame lateral vibration control

Bogie active stability simulation and scale rig test based on frame lateral vibration control

Lateral vibration control of monopile supported offshore wind turbines with toroidal tuned liquid column dampers

This study investigates the lateral vibration control efficiency of toroidal tuned liquid column dampers (TTLCDs) for monopile supported offshore wind turbines. The TTLCD has the advantage that it can be tuned to match the natural frequencies of wind turbines both in fore-aft and side–side directions simultaneously. A general mathematical modeling of the TTLCD inside the nacelle is derived and an interface between the simulation platforms MATLAB/Simulink and FAST is established. A TTLCD design procedure is provided for monopile wind turbines. Numerical calculations are carried out for different wind velocities, wave-wind misalignment angles and working conditions considering fatigue and ultimate load cases. A parametric analysis is performed on the flow resistance coefficient of TTLCDs. The results demonstrate that TTLCDs can effectively control lateral vibrations and improve the structural performance of monopile wind turbines against wind and wave loads.

Lateral vibration analysis and active control of the propeller-shafting system using a scaled experimental model

The effective control of the transverse vibration is critical for the propeller-shaft coupling system, where excessive vibrations may cause reliability problems for working equipment and radiated noise of marine vessels. This paper is concerned with the active control method of reducing the lateral vibration transmission for the propeller-shafting system using a 1:10 scaled ratio experimental model. The lateral vibration characteristics of the propeller-shaft coupling system are investigated first by the experimental method, identifying the propeller mode and shafting modes that dominate the peak frequencies of system responses. The active vibration control system taking the electromagnetic actuator as the control power source and the raft vibration acceleration as the active control target is proposed for base-point control and cross-point control strategies. An adaptive feedforward controller based on the equivalent interference principle is developed by the improved LMS algorithm with parameter scale transformation. The designed adaptive algorithm accelerates the convergence rate of the controller parameters and tracks the unknown frequency fluctuations of the time-varying disturbance. Experimental implementation of the proposed active controller is carried out, demonstrating the applicability of the improved algorithm on the lateral vibration control of the propeller-shafting system.

Lateral Vibration Control of Long-Span Small-Radius Curved Steel Box Girder Pedestrian Bridge with Distributed Multiple Tuned Mass Dampers.

Curved pedestrian bridges are important urban infrastructure with the desired adaptability to the landscape constraints and with aesthetic benefits. Pedestrian bridges feature thin cross-sections, which provide sufficient load capacities but lead to low natural frequencies that make the bridges susceptible to vibration under pedestrian excitation. This study investigates the lateral vibration of a curved bridge with a small radius down to 20 m, proposes an approach to mitigate the lateral vibration of bridges with large curvatures using distributed multiple tuned mass dampers (MTMD), and conducts in-situ bridge tests to evaluate the vibration mitigation performance. The lateral vibration was investigated through in-situ tests and finite element analysis as well as the code requirements. The key parameters of the distributed MTMD system were improved by strategically selecting the mass ratio, bandwidth, center frequency ratio, and damper number. The results showed that the curved bridge was subjected to significant lateral vibration due to the coupling of torque and moment, and the recommended design parameters for the studied bridge were derived, i.e., the total mass ratio is 0.02, bandwidth is 0.15, center frequency ratio is 1.0, and damper number is 3. The proposed approach effectively improves the deployment of MTMD for lateral vibration control of the curved bridge. The field tests showed that the vibration was reduced by up to 82% by using the proposed approach.

Lateral vibration control of ball screw feed system considering the nut location

Lateral vibration control of ball screw feed system considering the nut location

Research on Time Delay Feedback Control of Lateral Vibration Axially Moving Viscoelastic Beam

The nonlinear dynamic behavior of a viscoelastic beam in axially variable motion under time delay is studied. Considering that the axial velocity pulsation and radial tension change periodically with time under the action of time delay, the viscous damping and finite support stiffness are taken into account, and the viscoelastic constitutive relationship adopts Kelvin model. A mathematical model of lateral vibration of an axially moving viscoelastic beam with changes in axial velocity and tension under time delay is established, and a partial differential-integral control equation describing the lateral nonlinear vibration of an axially moving beam is given. Based on the Galerkin truncation method, the control equations established based on the mechanical model are discretized, so that the direct multi-scale method obtains the numerical solution of the lateral nonlinear vibration of the axially moving beam under the action of time delay, and determines the nonlinear dynamic behavior of the system under the action of time delay. By analyzing the numerical solution of the vibration displacement and velocity at the midpoint of the beam, the whole process of the average velocity of the axially moving structure along the axis, the amplitude of the disturbance tension and the change of the viscoelastic coefficient is simulated. It provides a numerical theoretical basis for the study of the nonlinear dynamic behavior of axially moving beams under time delay.Through the research in this article, the introduction of time delay is studied, and the time delay is used to analyze the axial force that changes along the radial direction of the beam caused by the speed pulsation, and the theoretical framework for nonlinear vibration analysis of the axially moving viscoelastic beam is constructed to expand the time delay. The application scope of the nonlinear vibration theory and nonlinear dynamics theory, the development and improvement of the approximate analysis and numerical solution of the nonlinear continuum (especially the gyro body) under the action of time delay, to provide a theoretical basis for the analysis and design of the corresponding engineering system and technical reserves.

Reduction of Vibrations in Long‐Span Continuous Girder Bridges with Pounding Tuned Mass Dampers

Earthquakes often cause bridges to vibrate to different degrees; moreover, in the case of poor road conditions, the vibration amplitude of bridges caused by vehicles often exceeds a reasonable range, thus causing different degrees of damage to bridges. Therefore, this article studies the vibration reduction effect of the pounding tuned mass dampers (PTMD) on long‐span continuous bridges under earthquake and vehicle loads. The PTMD used in this study can reduce the vibration in both lateral and vertical directions. The PTMD provides a stronger vibration dampening effect compared to the TMD since it increases collision to use energy. The LS‐DYNA software is used for numerical modeling to optimize the parameters of the PTMD and to determine the size and installation position of the PTMD. Then, the bridge is subjected to two recorded ground motions, and the bridge response with and without the PTMD is compared and analyzed, which shows how PTMD might lessen bridge vibration in its transverse direction. To assess how efficiently the PTMD dampens vibrations induced by vehicle loads on bridges, a vehicle/bridge/PTMD system is simulated using a refined vehicle model. The findings demonstrate that the PTMD may significantly lessen the bridge’s lateral and vertical vibration while enhancing driving comfort. Thus, this research study is of great significance for vertical and lateral vibration control of long‐span continuous girder bridges.

Design of a Maglev Inertial Actuator with High Mass Power Ratio for Lateral Vibration Control of Propulsion Shafting

The maglev inertial actuators with high power and mass maybe effective for lateral vibration control of a propulsion shafting. But the mass power ratio of the actuators currently in use is too small to meet the requirements. In the paper, a maglev inertial actuator was innovatively designed with high mass power ratio. The structure of the magnetic circuit assembly and the suspending assembly were designed and optimized. To verify the property of the proposed maglev inertial actuator, a prototype with mass less than 8 kg was developed and tests were carried out. The minimum effective output force can reach 200 N within the frequency band of 20–300 Hz. A lateral vibration of a propulsion shafting system was constructed and the active control effect was tested. The experimental results show that the proposed maglev inertial actuator has a good effect on lateral vibration control of shafting.

Use of Deep Liquid-Containing Tanks as Dynamic Vibration Absorbers for Lateral Vibration Control of Structures: A Review

Use of Deep Liquid-Containing Tanks as Dynamic Vibration Absorbers for Lateral Vibration Control of Structures: A Review

Reduction of structural vibrations with the piezoelectric stacks ring

It is known that piezoelectric material shunted with external circuits can convert mechanical energy to electrical energy, which is so called piezoelectric shunt damping technology. In this paper, a piezoelectric stacks ring (PSR) is designed for vibration control of beams and rotor systems. A relative simple electromechanical model of an Euler Bernoulli beam supported by two piezoelectric stacks shunted with resonant RL circuits is established. The equation of motion of such simplified system has been derived using Hamilton’s principle. A more realistic FEA model is developed. The numerical analysis is carried out using COMSOL® and the simulation results show a significant reduction of vibration amplitude at the specific natural frequencies. Using finite element method, the influence of circuit parameters on lateral vibration control is discussed. A preliminary experiment of a prototype PSR verifies the PSR’s vibration reduction effect.

Active vibration control of ship mounted flexible rotor-shaft-bearing system during seakeeping

Rotor-shaft-bearing system is an integral part of the engine and propulsion system of a ship. Ships are subject to water-waves which cause large rigid body motion of the ship hull involving all six degrees of freedom. This large time-varying ship-motion causes parametric excitation to the flexible rotor mounted on the ship, and may generate high vibratory response of the rotor, although fairly balanced. This paper proposes active control of lateral vibration in such rotors with a suitably placed electromagnetic actuator and compares simulated performance (response amplitude and control current) of different control laws, namely, (i) PD, (ii) PID and (iii) two novel control laws inspired by the mechanical models of a viscoelastic semi-solid. Realistic ship motion during sea-keeping conditions is generated by numerically solving the governing differential equations of motion of a ship under the action of water waves, using indigenously developed code. The equations of motion of the discretized rotor continuum subject to forces from conventional bearings, base motion and the actuator are obtained with respect to a non-inertial reference frame attached to the moving rotor base. Multi-objective optimization of control gains is carried out to obtain minimum rotor-disk response at the expense of the optimum control current. Numerical simulations reveal that the novel control law proposed in (iii) is the most efficient in terms of vibration response and control cost.

Lateral vibration control and stabilization of the quasiperiodic oscillations for rotor-active magnetic bearings system

This work aims to improve the vibrational behaviors of the rotor-active magnetic bearings (AMB) system via proposing a new control methodology for such lateral vibrations. Accordingly, the rotor-AMB system model is modified by integrating the conventional proportional–derivative (PD) controller along with the positive position feedback (PPF) controller to the considered system. The control currents in the rotor-AMB system are designed to become a combination of two control signals: One of them is generated via the PD controller, and the other one comes from the PPF controller. Based on the suggested control method, the whole dynamical system model is derived and then analyzed by the multiple time-scale perturbation method. Then, the bifurcation diagrams of both the spinning speed and rotor eccentricity response curves are investigated before and after control. The obtained analytical results showed that the integrating of the PPF controller to the considered system could mitigate the system lateral vibration close to zero. Moreover, the system quasiperiodic motions have been stabilized after control and the sensitivity to the initial conditions has eliminated. Finally, numerical validations for the obtained analytical results are performed that illustrated an excellent agreement with the analytical ones.

Simulation and Experimental Study on the Active Stability of High-Speed Trains

An active hunting stability scheme is proposed for the high-speed trains based on frame lateral vibration control. The stability of the vehicle is improved by exerting active control force on the front and rear frames of the bogie. First, a simplified lateral vibration model of a single bogie is established to the control system design. The feedback gain matrix is obtained according to the linear quadratic optimal control theory. Then, the multibody dynamics model of the vehicle is built using SIMPACK, and the linear stability and straight running performance are analyzed under different working configurations. Finally, the active control effects are verified by a scaled roller rig. The results show that this active control scheme to improve the stability performances of vehicles through the feedback of frame vibration state is feasible.

Assessment of the Strengthening of Existing Benchmark Monorail Railway Bridge: A Case Study of a Generic Method for Lateral Reinforcement

In order to cope with the increasing volume of transportation, many railway bridges are in need of being strengthened especially for the reinforced concrete lightweight pier bridge. An original strengthening dynamic performance evaluation of a benchmark monorail heavy haul rail bridge is carried out in this study, with different alternatives, the vehicle-bridge coupling system model is set up based on the time-varying theory. After extensive numerical testing, the dynamic responses of the bridge and the running safety of the vehicle are calculated for different strengthening alternatives using the program Dynamic Interaction Analysis for Heavy-Haul Train-Bridge System. The responses of the bridge and RS indexes of the vehicle are all meeting the requirements of the specifications concerned. The present study verifies that the strengthening of the bridge is desirable for the lateral stiffness reinforcement method of the bridge, in contrast with the field measured data. The present research proposed a feasible and generic method for the lateral vibration control of railway bridges.

Lateral vibration control of a shafting-hull coupled system with electromagnetic bearings

In order to suppress lateral vibration transmission and reduce acoustic radiation of a shafting-hull coupled system, a new approach using electromagnetic bearings in the shafting system is proposed. The dynamic characteristics of the electromagnetic bearings, especially the equivalent stiffness and damping as well as the applicable scope of linearization of the electromagnetic bearings, are analysed at first. With the equivalent parameters, a dynamic model of the shafting-hull coupled system is established subsequently by using the frequency response synthesis method to derive frequency response functions associated with the lateral vibrations. Finally, the influence of the control parameters of the electromagnetic bearings on vibration transmission in the shafting-hull system is studied. Analysis results indicate that lateral vibration responses are suppressed significantly when electromagnetic bearings are introduced into the shafting-hull system, and as a result, sound radiation of the system is reduced, which demonstrates that the proposed approach is effective in controlling vibration transmission in the shafting system.

A semi-active tuned liquid column damper for lateral vibration control of high-rise structures: Theory and experimental verification

A semi-active tuned liquid column damper for lateral vibration control of high-rise structures: Theory and experimental verification

Stability enhancement of a high-speed train bogie using active mass inertial actuators

ABSTRACTIn this study, a method regarding frame lateral vibration control based on the state feedback of an additional oscillator is proposed, so as to improve the bogie hunting stability. The multi-objective optimisation method (MOOP), with two objective functions of the stability index and control effort, is solved by the NSGA-II algorithm to obtain the feedback gains. The frame lateral vibration control can effectively improve the bogie hunting stability according to the linear and non-linear analysis of a high-speed train bogie, in which a fault of the yaw damper and time delay in the control system are considered. The effect of the oscillator suspension parameters and time delay on the system stability and robustness are analysed. The results show that the damped vibration frequency of the oscillator should be equal to the bogie hunting frequency, but a harder oscillator suspension can be used to improve the hunting critical speed margin of the bogie control system. However, just as how the feeding the frame states back directly, a hard oscillator suspension will lead to instability in the control system at a certain time delay. Therefore, the improvement of bogie hunting stability and reduction of control system stability must be considered when optimising the oscillator parameters. For the 350 km/h train bogie covered in this study, the optimal mass, natural frequency and damping ratio of the additional oscillator are acquired.

Lateral vibration control of a precise machine using magneto-rheological mounts featuring multiple directional damping effect

In a previous work, magneto-rheological (MR) dampers were originally designed and implemented for reducing the vertical low-frequency vibration occurring in precise semi-conductor manufacturing equipment. To reduce the vibrations, an isolator levitated the manufacturing machine from the floor using pneumatic pressure which cut off the external vibration, while the MR damper was used to decrease the transient response of the isolator. However, it has been found that the MR damper also provides a damping effect on the lateral vibration induced by the high-speed plane motions. Therefore, in this work both vertical and lateral vibrations are controlled using the yield and shear stresses of the lateral directions generated from the MR fluids by applying a magnetic field. After deriving a vibration control model, an overall control logic is formulated considering both vertical and lateral vibrations. In this control strategy, a feedback loop associated with the laser sensor is used for vertical vibration control, while a feed-forward loop with the motion information is used for lateral vibration control. The experimental results show that the proposed concept is highly effective for lateral vibration control using the damping effect on multiple directions.

吸引式磁気浮上系における横ずれ方向の制振制御

吸引式磁気浮上系における横ずれ方向の制振制御