Investigation on the sensitive and insensitive zones of the rail support stiffness for the dynamic response of a vehicle system under low excitation frequencies

This paper summarizes applicable theory and data from simulation experiments on the directional control of automobiles subjected to crosswind gust disturbances. Measured driver/vehicle describing functions for several subjects and replications are presented and interpreted. It is shown that the driver's steering outputs can be explained as functions of lateral position and heading, although alternate interpretations involving path-angle and path-rate feedbacks are considered. The results demonstrate that driver/vehicle response properties can be modeled and measured for a class of important closed-loop driving tasks. They provide further direct experimental verification of the applicability of driver/vehicle theory to situations where the driver obtains his information from a real-world visual simulation.

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Study on Dynamic Response of Cylindrical Shells under Combined Load

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.333-335.2151 ◽

2013 ◽

Vol 333-335 ◽

pp. 2151-2155

Author(s):

Xue Feng Han ◽

Yan Dong Wang ◽

Tao Wang ◽

Tong Chao Ding ◽

Hong Guang Jia

Keyword(s):

Cylindrical Shell ◽

Dynamic Response ◽

Radial Displacement ◽

Compressive Load ◽

Axial Displacement ◽

Aerodynamic Load ◽

Displacement Response ◽

Calculation Results ◽

Circumferential Displacement ◽

Excitation Frequencies

In order to study the dynamic response of the cylindrical shell structure which is similar to the missile cabin under the combined effects of axial compressive load and radial aerodynamic load, the equilibrium equation of dynamic response of cylindrical shell is derived based on the Hamiltons principle. The displacement response of cylindrical shell is calculated through employing the numerical method. The calculation results show that the axial displacement response and the radial displacement response of cylindrical shell are much greater than the circumferential displacement response; the radial displacement will be maximum when the excitation frequencies are 285Hz, 594Hz, 1039Hz, 1062Hz, 1093Hz, 1962Hz and 1987Hz; the axial displacement will be maximum when the corresponding excitation frequencies are 81Hz and 294Hz; the peak values of displacement response in non-load plane are not all obtained at the resonance frequency and a certain effect is generated due to the modal coupling.

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On the Construction and Use of Surrogate Models for the Dynamic Analysis of Multibody Systems

Volume 13: New Developments in Simulation Methods and Software for Engineering Applications; Safety Engineering, Risk Analysis and Reliability Methods; Transportation Systems ◽

10.1115/imece2009-10277 ◽

2009 ◽

Cited By ~ 1

Author(s):

H. Ansari Ardeh ◽

M. Tupy ◽

D. Negrut

Keyword(s):

Dynamic Response ◽

Surrogate Model ◽

Tire Model ◽

Learning Stage ◽

Quarter Car Model ◽

Car Model ◽

Vehicle System ◽

Main Challenge ◽

Time Required ◽

Two Stages

This study outlines an approach for speeding up the simulation of the dynamic response of vehicle models that include hysteretic nonlinear tire components. The method proposed replaces the hysteretic nonlinear tire model with a surrogate model that emulates the dynamic response of the actual tire. The approach is demonstrated via a dynamic simulation of a quarter vehicle model. In the proposed methodology, training information generated with a reduced number of harmonic excitations is used to construct the tire hysteretic force emulator using a Neural Network (NN) element. The proposed approach has two stages: a learning stage, followed by an embedding of the learned model into the quarter car model. The learning related main challenge stems from the attempt to capture with the NN element the behavior of a hysteretic element whose response depends on its loading history. The methodology is demonstrated in conjunction with a simple nonlinear quarter vehicle system as well as an ADAMS based model that uses a complex tire element. The results obtained with the surrogate model prove to be accurate and are obtained at a fraction of the CPU time required to handle the original models. The approach proposed is anticipated to be useful for reducing the duration of vehicle simulations, or when a tire model is not available but experimental data can be used to generate a surrogate model.

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Measurement and interpretation of driver/vehicle system dynamic response

Applied Ergonomics ◽

10.1016/0003-6870(74)90370-6 ◽

1974 ◽

Vol 5 (3) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

D.H. Weir ◽

D.T. McRuer

Keyword(s):

Dynamic Response ◽

System Dynamic ◽

Vehicle System

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Effect of wheel polygonalization on the Degree of Non-linearity of dynamic response of high-speed vehicle system

Measurement and Control ◽

10.1177/00202940211035405 ◽

2021 ◽

pp. 002029402110354

Author(s):

Chen Shuangxi ◽

Ni Yanting

Keyword(s):

Dynamic Response ◽

Health Monitoring ◽

Extraction Method ◽

High Speed ◽

Vibration Response ◽

High Speed Train ◽

Coupled Dynamics ◽

Vehicle System ◽

Parameters Extraction ◽

Non Linear

Polygonalization of the wheel describes the growth of out-of-round profiles of the wheels of railway vehicle. This problem was identified in the 1980s but its mechanism is still not well understood. The wheel-rail disturbance formed by wheel polygonalization will accelerate the fatigue fracture of the key parts of rail vehicles and seriously threaten the safety of rail vehicle. This fact has led to significant efforts in detecting and diagnosing wheel polygonalization, in particular in setting the criteria for health monitoring. Currently, the time-domain feature parameters extraction method based on data statistics and frequency-domain feature parameters extraction method based on spectrum estimation are widely applied to detect wheel polygonalization. However, the basis of spectral estimation is the Fourier transform, which is not good at dealing with non-linear vibration systems (such as vehicle-track coupled system). Aiming at the wheel polygonalization problem existing in high-speed train, the non-linear extent of vibration response of vehicle system caused by wheel polygonalization is analyzed based on vehicle-track coupled dynamics and adaptive data analysis method. A typical high-speed train model is established according to the vehicle-track coupled dynamics theory. The wheel polygonalization model is introduced and vehicle system vibration response is calculated by numerical integration. The vibration response signal is decomposed by empirical mode decomposition (EMD) to produce the intrinsic mode functions (IMFs). By calculating the intra-wave frequency modulation of IMFs, that is, the difference between instantaneous and mean frequencies and amplitudes, the non-linearity of the dynamic response is quantified. Influences of wheel polygonalization on the non-linearity of steady-state and unsteady vibration responses of vehicle system are analyzed in detail. An objective criterion for wheel polygonalization health monitoring based on Degree of Non-linearity is proposed, which provides an effective tool for prognostics and health management of trains.

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Estimation of Dynamic Response Index Domain of High Speed Railway Vehicle System

Advances in Transdisciplinary Engineering - ISMR 2020 ◽

10.3233/atde200230 ◽

2020 ◽

Author(s):

Xulu Wang ◽

Limin Chang

Keyword(s):

Dynamic Response ◽

High Speed ◽

Statistical Characteristics ◽

Inversion Method ◽

Estimation Model ◽

Response Index ◽

Irregularity Index ◽

Vehicle System ◽

Track Irregularity ◽

Damage Condition

Based on the dynamic simulation model, the dynamic response index of vehicle system under the action of track irregularity is divided into three areas: repair, deterioration and maintenance. The correlation between the track irregularity index and the dynamic response index domain of vehicle system components is calculated and statistically studied. The estimation model of dynamic response index domain of vehicle system and the domain boundaries of different dynamic response indexes are established and obtained Line. According to the principle of single variable method, the excitation source of vehicle track system is divided into track irregularity and other comprehensive factors (such as temperature load, material damage, etc.), and a simple inversion method of track foundation state is proposed based on the estimation model of dynamic response index domain. Its basic principle is: if the statistical characteristics of track irregularity remain unchanged and other influencing factors change, the estimation domain and measurement domain of dynamic response index will produce grade jump, so as to determine whether the basic state of the line is normal. The simulation results show that the accuracy of domain estimation of dynamic response index of vehicle system is more than 80%, and the accuracy of recognition is more than 70% for the damage condition of the line infrastructure, where the fastener is empty.

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Holographic Interferometry in Automotive Powertrain Component Engineering Analysis

Volume 3C: 15th Biennial Conference on Mechanical Vibration and Noise — Vibration Control, Analysis, and Identification ◽

10.1115/detc1995-0722 ◽

1995 ◽

Author(s):

James W. Forbes ◽

Mitchell M. Marchi ◽

Alexander Petniunas ◽

Raymond R. Wales

Keyword(s):

Dynamic Response ◽

Holographic Interferometry ◽

Structural Integrity ◽

Engineering Analysis ◽

Design Requirement ◽

Noise And Vibration ◽

Vehicle System ◽

System Components ◽

Automotive Powertrain ◽

System Requirements

Abstract As increased performance and vehicle system requirements are placed on automotive powertrains more sophisticated methods of engineering analysis are required in their development. Since the containment of noise and vibration is a major design requirement for powertrains, experimental techniques such as laser holographic interferometry are used to tune the dynamic response of system components. This allows the overall system to be optimized from a noise and vibration standpoint as well as from the standpoint of structural integrity. This paper will discuss a variety of examples of how powertrain components have been optimized with the use of holographic methodology.

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