Development of a Rigid Ring Quarter-Vehicle Model With an Advanced Road Profile Algorithm for Durability and Ride Comfort Predictions

2008 ◽  
Author(s):  
James Allen ◽  
Moustafa El-Gindy ◽  
Kevin Koudela
Keyword(s):  
Ride Comfort ◽  
Integration Time ◽  
Vertical Acceleration ◽  
Vehicle Model ◽  
Time Step ◽  
Element Analysis ◽  
Rigid Ring ◽  
Fully Integrated ◽  
Road Profile ◽  
Vertical Contact

In this paper a new five-degree-of-freedom in-plane Rigid Ring Quarter-Vehicle Model (RRQVM) with a Force Dependent Effective Road Profile (FDERP) is derived and programmed in MATLAB/Simulink©. This novel fully integrated model uses the tire-road vertical contact force to update the effective road height and slope at each integration time step. The model is capable of simulating the response of a free rolling tire over arbitrarily uneven road surfaces to study vehicle ride comfort and durability with efficient, accurate results. The RRQVM is validated with tire spindle vertical acceleration data from virtual Finite Element Analysis (FEA) Quarter-Vehicle Model (QVM) tests. A baseline in-plane RRQVM with a Force Independent Effective Road Profile (FIERP) is also developed for comparison with the FDERP RRQVM. Results show that the FDERP RRQVM predicts the vertical tire spindle acceleration more accurately than the FIERP RRQVM when compared to the FEA RRQVM results, especially at speeds above 11 km/hr. Therefore, the advanced FDERP model provides the RRQVM with a more accurate effective road profile than a conventional FIERP model.

scholarly journals The Influence of an Integration Time Step on Dynamic Calculation of a Vehicle-Track-Bridge under High-Speed Railway

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 431
Author(s):  
Junjie Ye ◽  
Hao Sun
Keyword(s):  
High Speed ◽  
Coupled Model ◽  
Short Wave ◽  
Integration Time ◽  
Vertical Acceleration ◽  
Dynamic Calculation ◽  
Time Step ◽  
High Speed Railway ◽  
Track Irregularity ◽  
Track Bridge

In order to study the influence of an integration time step on dynamic calculation of a vehicle-track-bridge under high-speed railway, a vehicle-track-bridge (VTB) coupled model is established. The influence of the integration time step on calculation accuracy and calculation stability under different speeds or different track regularity states is studied. The influence of the track irregularity on the integration time step is further analyzed by using the spectral characteristic of sensitive wavelength. According to the results, the disparity among the effect of the integration time step on the calculation accuracy of the VTB coupled model at different speeds is very small. Higher speed requires a smaller integration time step to keep the calculation results stable. The effect of the integration time step on the calculation stability of the maximum vertical acceleration of each component at different speeds is somewhat different, and the mechanism of the effect of the integration time step on the calculation stability of the vehicle-track-bridge coupled system is that corresponding displacement at the integration time step is different. The calculation deviation of the maximum vertical acceleration of the car body, wheel-sets and bridge under the track short wave irregularity state are greatly increased compared with that without track irregularity. The maximum vertical acceleration of wheel-sets, rails, track slabs and the bridge under the track short wave irregularity state all show a significant declining trend. The larger the vibration frequency is, the smaller the range of integration time step is for dynamic calculation.

Ride Comfort of Five-Axle Tractor/Semi-Trailer

2000 ◽  
Author(s):  
Zhenyu Jiang ◽  
Moustafa El-Gindy ◽  
Donald Streit
Keyword(s):  
Ride Comfort ◽  
General Concept ◽  
Ride Quality ◽  
Vertical Acceleration ◽  
Gaussian Random Process ◽  
Long Distance ◽  
Power Spectral ◽  
Road Profile ◽  
Computer Based ◽  
Simulation Results

Abstract The issue of ride comfort for vehicle operations has recently generated considerable interest especially in heavy vehicle systems since long-distance drivers are more likely to experience high levels of vibration. This paper introduces the general concept of vibration-related health problems, discusses ride comfort assessment criteria and methods, and then focuses on the methodology of using computer simulation to analyze ride comfort. The computer-based ride comfort model can be divided into three sub-models: vehicle model, driver/seat model, and road profile input model. Several vehicle models and driver/seat models are reviewed and detailed modeling techniques are introduced. A five-axle tractor/semi-trailer/driver combination ride comfort simulation model is developed in this paper using the software DADS. Both four-spring tandem suspension and independent air spring suspension are studied. Road profiles are assumed as static zero mean Gaussian random process. Vertical acceleration at the interface between seat and driver body is obtained from simulation results. Power spectral density and root mean square (RMS) vertical acceleration are calculated based on simulation results. RMS acceleration at ISO classified good and average roads are compared with ISO 8-hour fatigue vibration limit. It is found that RMS acceleration of this particular vehicle simulated in this paper is below the ISO 8-hour fatigue limit for both good and average roads when traveling at the speed of fifty miles per hour. This implies a good ride comfort. Axle dynamic load coefficients (DLC) are calculated for four suspension configurations that are combinations of air springs and steel springs. Results show that large DLC doesn’t necessarily indicate bad ride quality.

Advanced effective road profile filter for a rigid ring tyre quarter-vehicle model

2013 ◽  
Vol 1 (1) ◽  
pp. 28
Author(s):  
James R. Allen <suffix>II</suffix> ◽  
Moustafa El Gindy
Keyword(s):  
Vehicle Model ◽  
Rigid Ring ◽  
Road Profile

scholarly journals The Control of an Active Seat Suspension Using an Optimised Fuzzy Logic Controller, Based on Preview Information from a Full Vehicle Model

Vibration ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 20-40 ◽  
Author(s):  
Abdulaziz Alfadhli ◽  
Jocelyn Darling ◽  
Andrew Hillis
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Logic Controller ◽  
Ride Comfort ◽  
Vertical Direction ◽  
Front Axle ◽  
Rule Base ◽  
Vertical Acceleration ◽  
Vehicle Speed ◽  
Vehicle Model ◽  
Full Vehicle

The use of suspension preview information obtained from a quarter vehicle model (QvM) to control an active seat has been shown by the authors to be very promising, in terms of improved ride comfort. However, in reality, a road vehicle will be subjected to disturbances from all four wheels, and therefore the concept of preview enhanced control should be applied to a full vehicle model. In this paper, different preview scenarios are examined, in which suspension data is taken from all or limited axles. Accordingly, three control strategies are hypothesized—namely, front-left suspension (FLS), front axle (FA), and four wheel (4W). The former utilises suspension displacement and velocity preview information from the vehicle suspension nearest to the driver’s seat. The FA uses similar preview information, but from both the front-left and front-right suspensions. The 4W controller employs similar preview information from all of the vehicle suspensions. To cope with friction non-linearities, as well as constraints on the active actuator displacement and force capabilities, three optimal fuzzy logic controllers (FLCs) are developed. The structure of each FLC, including membership functions, scaling factors, and rule base, was sequentially optimised based on improving the seat effective amplitude transmissibility (SEAT) factor in the vertical direction, using the particle swarming optimisation (PSO) algorithm. These strategies were evaluated in simulation according to ISO 2631-1, using different road disturbances at a range of vehicle forward speeds. The results show that the proposed controllers are very effective in attenuating the vertical acceleration at the driver’s seat, when compared with a passive system. The controller that utilised suspension preview information from all four corners of the car provided the best seat isolation performance, independent of vehicle speed. Finally, to reduce the implementation cost of the “four suspension” controller, a practical alternative is developed that requires less measured preview information.

An Implicit Ring Tire Model for Multibody Simulation with Energy Dissipation

2014 ◽  
Vol 42 (2) ◽  
pp. 62-84
Author(s):  
Louis Gagnon ◽  
Marc J. Richard ◽  
Pierangelo Masarati ◽  
Marco Morandini ◽  
Guy Doré
Keyword(s):  
Finite Element ◽  
Transient Behavior ◽  
Coefficient Of Determination ◽  
Vertical Force ◽  
Tire Model ◽  
Multibody Simulation ◽  
Time Step ◽  
Element Analysis ◽  
The Road ◽  
Road Profile

ABSTRACT A rigid ring tire model was developed as the c++ module of a free multibody dynamics software. It takes as input the longitudinal profile of the road and is attached to the wheel element of a multibody simulation. It is intended to evaluate the transient behavior of the tire rolling on a deteriorated road profile. It is tailored for, but not restricted to, applications at low camber angles, limited steering and velocity changes, and continuous contact with the road. It is expected to be accurate under excitation frequencies up to 100 Hz and road deformation up to 10 cm. It takes 45 tire parameters and 20 algorithm parameters and is integrated implicitly except for the road profile. The model has been calibrated and validated against a trusted finite element analysis of Michelin XZA-3 tires mounted on a wheel and axle assembly going over rectangular cleats. The resulting curves showed good agreement with the finite element data. The Nelder-Mead optimization process used on the manually determined parameters was able to increase the average coefficient of determination of the 12 test curves from −0.4 to 0.6. Above 20 km/h, that coefficient was better than 0.8 for every test of the vertical force response to cleats. As for the longitudinal forces, only one curve had a coefficient below 0.5. A variable time-step algorithm was also included in the module and found to reduce the simulation time of the test cases by roughly 85%.

Techniques for Determining the Parameters of a Two-Dimensional Tire Model for the Study of Ride Comfort

1997 ◽  
Vol 25 (3) ◽  
pp. 187-213 ◽  
Author(s):  
F. Mancosu ◽  
G. Matrascia ◽  
F. Cheli
Keyword(s):  
Physical Properties ◽  
Ride Comfort ◽  
Dynamic Test ◽  
Longitudinal Direction ◽  
Tire Model ◽  
Rigid Ring ◽  
Ring Model ◽  
Mass Moment ◽  
A New Technique ◽  
And Performance

Abstract A rigid ring model of the tire for the study of in-plane dynamics and a new technique for determining the parameters of the model are presented in this paper. This model can be used for studying the comfort of vehicles, problems of driving, and braking problems in the longitudinal direction. Comparison with finite element models shows that the rigid ring model of the tire is capable of describing the in-plane eigenmode shapes in the frequency range of 0–130 Hz. The well-known “brush model,” integrated into the tire model, is introduced to take into account the slide phenomena in the contact patch. The parameters of the model can be correlated with the physical properties of the tire so that designers can take advantage of such a correlation in the development of new tires in terms of time, cost, and performance. The technique used to determine the parameters of the model for some automobile tires include the direct measurements of some physical properties (mass, moment of inertia, stiffness) and a method of identification applied on the results from a dynamic test. The model is able to predict experimental data in terms of natural frequencies and relative dampings. Results from the application of this technique on two tires are reported.

Application of Practical Observer to Semi-Active Suspensions

1998 ◽  
Vol 122 (2) ◽  
pp. 284-289 ◽  
Author(s):  
H. Nakai ◽  
S. Oosaku ◽  
Y. Motozono
Keyword(s):  
Ride Comfort ◽  
Difficult Problem ◽  
Nonlinear Observer ◽  
Vertical Acceleration ◽  
Acceleration Sensor ◽  
Active Suspensions ◽  
Linear Observer ◽  
Gain Scheduled

This paper presents the development of gain-scheduled observers for semi-active suspensions. The states of the semi-active suspensions must be accurately obtained because the accuracy directly affects system performances such as ride comfort. Nonlinearity in the absorber of the semi-active suspensions is a difficult problem for estimating the accurate states using conventional linear observer theories. To solve this problem, we have designed a new gain-scheduled observer by introducing two improvements. The validity of this nonlinear observer was confirmed by simulations and experiments. The results indicate that the present observer can accurately estimate the suspension stroke velocity using the vertical acceleration sensor on the sprung mass. [S0022-0434(00)02302-9]

scholarly journals MHDSTS: a new explicit numerical scheme for simulations of partially ionised solar plasma

2018 ◽  
Vol 615 ◽  
pp. A67 ◽  
Author(s):  
P. A. González-Morales ◽  
E. Khomenko ◽  
T. P. Downes ◽  
A. de Vicente
Keyword(s):  
Numerical Scheme ◽  
Operator Splitting ◽  
Conservation Equation ◽  
Ambipolar Diffusion ◽  
Point Of View ◽  
Integration Time ◽  
Solar Photosphere ◽  
Time Step ◽  
Diffusion Term ◽  
Fluid Approximation

The interaction of plasma with magnetic field in the partially ionised solar atmosphere is frequently modelled via a single-fluid approximation, which is valid for the case of a strongly coupled collisional media, such as solar photosphere and low chromosphere. Under the single-fluid formalism the main non-ideal effects are described by a series of extra terms in the generalised induction equation and in the energy conservation equation. These effects are: Ohmic diffusion, ambipolar diffusion, the Hall effect, and the Biermann battery effect. From the point of view of the numerical solution of the single-fluid equations, when ambipolar diffusion or Hall effects dominate can introduce severe restrictions on the integration time step and can compromise the stability of the numerical scheme. In this paper we introduce two numerical schemes to overcome those limitations. The first of them is known as super time-stepping (STS) and it is designed to overcome the limitations imposed when the ambipolar diffusion term is dominant. The second scheme is called the Hall diffusion scheme (HDS) and it is used when the Hall term becomes dominant. These two numerical techniques can be used together by applying Strang operator splitting. This paper describes the implementation of the STS and HDS schemes in the single-fluid code MANCHA3D. The validation for each of these schemes is provided by comparing the analytical solution with the numerical one for a suite of numerical tests.

Time step constraints in finite element analysis of the poisson type equation

1989 ◽  
Vol 31 (2) ◽  
pp. 269-273 ◽  
Author(s):  
V. Murti ◽  
S. Valliappan ◽  
N. Khalili-Naghadeh
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Type Equation ◽  
Time Step ◽  
Element Analysis ◽  
Poisson Type

Dynamic Co-Simulation Methods for Combined Transmission-Distribution System With Integration Time Step Impact on Convergence

2019 ◽  
Vol 34 (2) ◽  
pp. 1171-1181 ◽  
Author(s):  
Ramakrishnan Venkatraman ◽  
Siddhartha Kumar Khaitan ◽  
Venkataramana Ajjarapu
Keyword(s):  
Distribution System ◽  
Integration Time ◽  
Simulation Methods ◽  
Time Step
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