scholarly journals Optimizing Vibration Attenuation Performance of a Magnetorheological Damper-Based Semi-active Seat Suspension Using Artificial Intelligence

2019 ◽  
Vol 6 ◽  
Author(s):  
Xinhua Liu ◽  
Ningning Wang ◽  
Kun Wang ◽  
Hui Huang ◽  
Zhixiong Li ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Magnetorheological Damper ◽  
Seat Suspension ◽  
Vibration Attenuation ◽  
Vibration Attenuation Performance

scholarly journals Integrated active and semi-active control for seat suspension of a heavy duty vehicle

2017 ◽  
Vol 29 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Donghong Ning ◽  
Shuaishuai Sun ◽  
Haiping Du ◽  
Weihua Li
Keyword(s):  
Resonance Frequency ◽  
Active Control ◽  
Integrated Control ◽  
Relative Displacement ◽  
Magnetorheological Damper ◽  
Active Force ◽  
Heavy Duty ◽  
Force Output ◽  
Seat Suspension ◽  
A Current

In this article, an integrated active and semi-active seat suspension for heavy duty vehicles is proposed, and its prototype is built; an integrated control algorithm applied measurable variables (suspension relative displacement and seat acceleration) is designed for the proposed seat prototype. In this seat prototype, an active actuator with low maximum force output (70 N), which is insufficient for an active seat suspension to control the resonance vibration, is applied together with a rotary magnetorheological damper. The magnetorheological damper can suppress the high vibration energy in resonance frequency, and then a small active force can further improve the seat suspension performance greatly. The suspension’s dynamic property is tested with a MTS system, and its model is identified based on the testing data. A modified on–off controller is applied for the rotary magnetorheological damper. A [Formula: see text] controller with the compensation of a disturbance observer is used for the active actuator. Considering the energy saving, the control strategy is designed as that only when the magnetorheological damper is in the off state (0 A current), the active actuator will have active force output, or the active actuator is off. Both simulation and experiment are implemented to verify the proposed seat suspension and controller. In the sinusoidal excitations experiment, the acceleration transmissibility of integrated control seat has lowest value in resonance frequency and frequencies above the resonance, when compared with power on (0.7 A current), power off (0 A current) and semi-active control seat. In the random vibration experiment, the root mean square acceleration of integrated control seat suspension has 47.7%, 33.1% and 26.5% reductions when compared with above-mentioned three kinds of seat suspension. The power spectral density comparison indicates that the integrated seat suspension will have good performance in practical application. The integrated active and semi-active seat suspension can fill energy consumption gap between active and semi-active control seat suspension.

Reduction of Whole Body Vibration in a Wide Frequency Range Using Inflation Pressure Control of Air Bladder Cushion

2021 ◽  
Author(s):  
Pavan Nuthi ◽  
Yixin Gu ◽  
Aida Nasirian ◽  
Alexandra Lindsay ◽  
Himanshu Purandare ◽  
...  
Keyword(s):  
Whole Body Vibration ◽  
Wide Frequency Range ◽  
Whole Body ◽  
Frequency Range ◽  
Inflation Pressure ◽  
Cell Array ◽  
Frequency Sweep ◽  
Body Vibration ◽  
Vibration Attenuation ◽  
Vibration Attenuation Performance

Abstract Several types of interfaces like foam and inflated air cells exist to reduce the effect of mechanical vibration experienced in human-machine interfaces in different scenarios such as transportation. However, their vibration attenuation performance in a wide frequency range relevant to whole body vibration (1–80 Hz) leaves much to be desired. In this study, we investigate the effect of inflation pressure on the vibration attenuation behavior of an air cell cushion. An experimental setup capable of conducting frequency sweep tests and regulating inflation pressure in an air cell array cushion was developed. Frequency sweep tests were conducted at various inflations and the vibration transmissibilities at static inflations were plotted. A dynamic inflation scheme was developed based on the apriori knowledge of inflation dependent transmissibilities. Furthermore, the closed loop behavior of the inflation scheme was evaluated with a frequency sweep test. The resulting closed loop transmissibility indicated better vibration attenuation performance than any single static inflation for the air cell array cushion in the range of frequencies relevant to whole body vibration. This result lays the groundwork for potential air cell cushions which modify their inflation dynamically through a direct feedback from sensors like accelerometers to attenuate vibration in a wide frequency range.

A sky-hook sliding mode semiactive control for commercial truck seat suspension

2020 ◽  
pp. 107754632094097
Author(s):  
Qiang Chen ◽  
Yong Zhang ◽  
Chengwei Zhu ◽  
Jinbo Wu ◽  
Ye Zhuang
Keyword(s):  
Nonlinear System ◽  
Phase Portrait ◽  
Control Method ◽  
Reference Model ◽  
Sliding Mode ◽  
Tracking Error ◽  
Magnetorheological Damper ◽  
Nonlinear Controller ◽  
Parameter Uncertainties ◽  
Seat Suspension

A semiactive seat suspension control method is proposed in this study and applied to attenuate the vibration of the commercial truck seat for enhancing its ride comfort. The semiactive seat suspension system with a magnetorheological damper behaves with undesirable nonlinear properties. The proposed controller is a typical nonlinear controller, which takes the ideal sky-hook controller as the reference model and forces the tracking error vector. The controller has achieved great performance of attenuating vibration and is robust to parameter uncertainties and external disturbances. The relaxation oscillation phenomenon and convergence were also analyzed by the contribution of the phase portrait. As the phase portrait depicted, the sky-hook controller, a weakly nonlinear system, could be approximated by the equivalent linear approximate model. However, the proposed controller, the sky-hook sliding mode controller, is a strongly nonlinear system, which could not be linearized by the regular perturbation theory, and the criterion is given by the phase portrait. The experiment results showed good agreement with the simulation results, and some other matters encountered were also analyzed in the process of application.

No-Jerk Skyhook Control Methods for Semiactive Suspensions

2004 ◽  
Vol 126 (4) ◽  
pp. 580-584 ◽  
Author(s):  
Mehdi Ahmadian ◽  
Xubin Song ◽  
Steve C. Southward
Keyword(s):  
Relative Velocity ◽  
Magnetorheological Damper ◽  
Damping Force ◽  
Electrical Currents ◽  
Zero Crossings ◽  
Seat Suspension ◽  
Suspension Systems ◽  
Heavy Truck ◽  
The Relationship ◽  
Study Offer

This paper presents two alternative implementations of skyhook control, named “skyhook function” and “no-jerk skyhook,” for reducing the dynamic jerk that is often experienced with conventional skyhook control in semiactive suspension systems. An analysis of the relationship between the absolute velocity of the sprung mass and the relative velocity across the suspension are used to show the damping-force discontinuities that result from the conventional implementation of skyhook control. This analysis shows that at zero crossings of the relative velocity, conventional skyhook introduces a sharp increase (jump) in damping force, which, in turn, causes a jump in sprung-mass acceleration. This acceleration jump, or jerk, causes a significant reduction in isolation benefits that can be offered by skyhook suspensions. The alternative implementations of skyhook control included in this study offer modifications to the formulation of conventional skyhook control such that the damping force jumps are eliminated. The alternative policies are compared to the conventional skyhook control in the laboratory, using a base-excited semiactive system that includes a heavy-truck seat suspension. An evaluation of the damping force, seat acceleration, and the electrical currents supplied to a magnetorheological damper, which is used for this study, shows that the alternative implementations of skyhook control can entirely eliminate the damping-force discontinuities and the resulting dynamic jerks caused by conventional skyhook control.

scholarly journals A seat suspension with a rotary magnetorheological damper for heavy duty vehicles

2016 ◽  
Vol 25 (10) ◽  
pp. 105032 ◽  
Author(s):  
S S Sun ◽  
D H Ning ◽  
J Yang ◽  
H Du ◽  
S W Zhang ◽  
...  
Keyword(s):  
Magnetorheological Damper ◽  
Heavy Duty ◽  
Seat Suspension ◽  
Heavy Duty Vehicles

Modeling and Verification of an Innovative Active Pneumatic Vibration Isolation System

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
H. Porumamilla ◽  
A. G. Kelkar ◽  
J. M. Vogel
Keyword(s):  
Natural Frequency ◽  
Vibration Isolation ◽  
Computational Study ◽  
Hydraulic Cylinder ◽  
Magnetorheological Damper ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Seat Suspension ◽  
Active Vibration ◽  
Novel Concept

This paper presents a novel concept in active pneumatic vibration isolation. The novelty in the concept is in utilizing an air-spring-orifice-accumulator combination to vary the natural frequency as well as inject damping into the system per requirement, thereby eliminating the need for a hydraulic cylinder or a magnetorheological damper. This continuously variable natural frequency and damping (CVNFD) technology is aimed at achieving active vibration isolation. For analysis purposes, a particular application in the form of pneumatic seat suspension for off-road vehicles is chosen. A mathematical model representing the system is derived rigorously from inertial dynamics and first principles in thermodynamics. Empirical corelations are also used to include nonlinearities such as friction that cannot be accounted for in the thermodynamic equations. An exhaustive computational study is undertaken to help understand the physics of the system. The computational study clearly depicts the CVNFD capability of the vibration isolation system. An experimental test rig is built to experimentally validate analytical and simulation modeling of the system. Experimental verification corroborated the variable natural frequency and damping characteristic of the system observed through computational simulations.

Estimation of the Transmissibility of Anti-Vibration Gloves when Used with Specific Tools

2005 ◽  
Vol 36 (9) ◽  
pp. 11-20
Author(s):  
Ren G. Dong ◽  
Dan E. Welcome ◽  
Thomas W. McDowell ◽  
Subhash Rakheja
Keyword(s):  
Transfer Function ◽  
Function Method ◽  
Protective Equipment ◽  
Transfer Function Method ◽  
Vibration Attenuation ◽  
Specific Performance ◽  
Vibration Transmissibility ◽  
Potential Risks ◽  
Series Of Experiments ◽  
Vibration Attenuation Performance

Anti-vibration gloves are increasingly being used as personal protective equipment to help reduce the hazards of hand-transmitted vibration. A vibration transfer function method for estimating the tool-specific performance of anti-vibration gloves has been proposed to help select appropriate gloves for particular tools and to assess the potential risks posed by tool vibration. This study evaluates the validity of the method by comparing the predicted vibration transmissibility with the measured value. Two typical vibration-attenuating gloves (air-bladder and visco-elastic material gloves) were used in the study. Two series of experiments were performed for the evaluation. In the first series, the isolation efficiency of selected anti-vibration gloves was evaluated in the laboratory under synthesized handle vibration spectra of six different tools. The second series of tests involved the measurement of the glove transmissibility, while operating two different pneumatic chipping hammers. The results of the study show reasonably good agreements between the predicted and measured acceleration transmissibility values of the candidate gloves. It is thus concluded that the transfer function method provides a reasonably good estimate of vibration attenuation performance of gloves for specific tools.

scholarly journals Experimental Study of a Variable Stiffness Seat Suspension Installed With a Compact Rotary MR Damper

2021 ◽  
Vol 8 ◽  
Author(s):  
Shuaishuai Sun ◽  
Jian Yang ◽  
Penghui Wang ◽  
Masami Nakano ◽  
Longjiang Shen ◽  
...  
Keyword(s):  
Ride Comfort ◽  
Excitation Frequency ◽  
Mr Damper ◽  
Variable Stiffness ◽  
Excitation Amplitude ◽  
Harmonic Excitation ◽  
Random Excitation ◽  
Shaking Table ◽  
Seat Suspension ◽  
Vibration Attenuation Performance

Traditional MR seat suspension without stiffness control is not able to avoid the resonance between the excitation and the seat, though it can dampen the vibration energy. To solve this problem, this paper proposed a variable stiffness (VS) magnetorheological (MR) damper to implement an advanced seat suspension. Its natural frequency can be shifted away from the excitation frequency through the variations of stiffness, thereby realizing the non-resonance control. The new seat suspension is designed and prototyped first, and then its dynamic property under different energizing current, excitation amplitude, and excitation frequency was tested using an MTS machine. The testing results verified its stiffness controllability. The vibration attenuation performance of the seat suspension was also evaluated on a vibration shaking table. The vibration reduction performance of the seat suspension was evaluated under two kinds of excitations, i.e., harmonic excitation and random excitation; the experimental results indicate that the new seat suspension outperforms passive seat suspensions regarding their ride comfort.

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