A study on the effect of different tyre imperfections on steering wheel vibration
TL;DR: In this paper, the authors analyse the steering wheel vibration, both shimmy and shake, excited by different tyre imperfections by using the commercial simulation package ADAMS/car 2005R2 and FTire.
Abstract: Multibody dynamics and tyre models have made possible detailed analysis not only for ride and handling, but also for determining their effects on tyre nonuniformities. The aim of this paper is to analyse the steering wheel vibration, both shimmy and shake, excited by different tyre imperfections by using the commercial simulation package ADAMS/car 2005R2 and FTire. Different settings with respect to imperfection locations, amount, and the combined effects of defects have been studied. An interesting beat phenomenon is observed when all the wheels have imperfections. A procedure to determine the type of imperfections in the tyre from the results of the test rig has also been proposed.
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Journal Article•
TL;DR: In this article, an application of nonlinear optimisation methods to select some parameters of a passenger car steering system is presented, where a simplified planar model of the system as well as spatial multibody models are developed.
Abstract: An application of nonlinear optimisation methods to select some parameters of a passenger car steering system is presented. A simplified planar model of the system as well as spatial multibody models are developed. The simplified model is used in the optimisation task, ensuring minimisation of vibrations of the steering wheel. The optimisation task is solved in two stages. The first one allow us to obtain optimal geometry of the system. In the second stage, nonlinear characteristics of some elements are obtained. The correctness of optimisation results is verified by the application of a more sophisticated spatial model. An own simulation programme has been worked out. It allowed us to perform dynamic analysis of the steering kickback using both simplified and complex structural models as well as to execute a built-in optimisation module.
Asymmetric input forces applied to the wheel centre have been used in the computer simulations. The excitations analysed are typical for a car moving over an obstacle. The work presented concentrates on the steering kickback phenomena, which may strongly influence discomfort perceived by the car driver.
2 citations
Cites methods from "A study on the effect of different ..."
...The commercial package ADAMS was applied in order to examine tire radial stiffness variation, static and dynamic imbalance and belt run-out by Balaramakrishna and Kumar (2009)....
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01 Jan 2013
TL;DR: In this article, the effect of wheel induced vibration on a quarter car model is analyzed using a brush tire model and the model is scripted in MATLAB and the simulation is run with a damper although without it the power increase would be much larger.
Abstract: Some of the most significant comfort disturbances in heavy vehicles can often be related to the wheels. In those cases, the vibration of the vehicle is excited by for example force variations within the tire, ovality of the tire or imbalance in the wheel. The disturbances are dependent on vehicle speed and are often perceived as most unpleasant at cruising speed on a motorway, at around 90 km/h.Truck manufacturers want to increase the robustness against this type of disturbance, since this results in an improved operator comfort. But it also makes it possible to lower the requirements on the suppliers of tires and rims, and thereby there is a financial gain for both customer and manufacturer.The aim with this project is to increase the understanding of wheel induced vibrations. In order to achieve this a literature survey has been performed on the subject. Furthermore, the phenomenon has been studied analytically by using a quarter car model which includes a brush tire model. The model is scripted in MATLAB.Simulations have been performed to analyse the effect on the chassis when forces excited by mass imbalance and radial run out are introduced.When looking at the second harmonic radial run out imperfection the unsprung mass, i.e the wheel, starts to bounce during the settling time.Also when comparing two different weights of a mass imbalance the power increase of the vibration in the sprung mass is much larger than the power increase of the unsprung mass at the specific frequency. This implies that the excitation frequency, the wheel rotation frequency in this case, is a harmonic repetition of the sprung mass undamped natural frequency.To avoid this phenomenon the undamped natural frequency of the sprung mass must change either by adding a damper or by changing the weight or the spring stiffness. The simulation is run with a damper although without it the power increase would be much larger.
References
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Book•
01 Jan 1965
TL;DR: In this paper, a new chapter on computational methods that present the basic principles on which most modern computer programs are developed is presented, which introduces an example on rotor balancing and expands on the section on shock spectrum and isolation.
Abstract: This edition features a new chapter on computational methods that presents the basic principles on which most modern computer programs are developed It introduces an example on rotor balancing and expands on the section on shock spectrum and isolation
2,196 citations
"A study on the effect of different ..." refers background in this paper
...This well-known phenomenon occurs due to two springs excited by close frequencies [15]....
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01 Apr 2002
TL;DR: In this article, a CAE study on steering wheel nibble was conducted using the design-of-experiments approach, and it was shown that a natural frequency that contributes reasonably to the nibble phenomenon is found in the steering gear.
Abstract: Many studies of mechanisms contributing to steering wheel nibble have been carried out in the past. This paper deals with some aspects that have not yet been studied, or those that have been presented by several authors but are deemed to be controversial. Firstly, an overview of stimulation sources (disturbance factors), and the significance these have with respect to steering nibble, is given. As an example of the controversial aspects of the problem, this paper deals with the assumption of dry friction in steering gear models and its conflict with the observed transfer of vibration caused by small (realistic) amounts of imbalance or tyre force variation. After modelling the steering gear resistance correctly, it is possible to identify, in the steering gear, a natural frequency that contributes reasonably to the nibble phenomenon. Based on this new model, a CAE study on parameter sensitivity, using the ‘design of experiments’ approach, is presented.
21 citations
"A study on the effect of different ..." refers background in this paper
...Neureder [1] studied the steering wheel nibble or shimmy due to different sources of excitations such as tyre imperfection, BTV, etc....
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...Among them two modes, namely rotational vibration of the steering wheel called the steering wheel nibble or shimmy and the vertical direction (up and down) motion called the shake [1,2], are important....
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...The torques are also a function of the operating speed [1,2]....
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...The same observations can be found in the literature [1]....
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...contribute to the steering wheel vibrations, though the complexity of interaction has been brought out [1]....
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16 May 2005
14 citations
"A study on the effect of different ..." refers background or result in this paper
...seems to be much less sensitive to rolling phase angle difference, and the trend of these results matches the literature results [2]....
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...path for vibrations to the steering system [2]....
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...[2] studied the tyre mass imbalance, rolling phase difference effect, and the inflation pressure effect on the steering wheel vibrations....
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...Among them two modes, namely rotational vibration of the steering wheel called the steering wheel nibble or shimmy and the vertical direction (up and down) motion called the shake [1,2], are important....
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...The torques are also a function of the operating speed [1,2]....
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TL;DR: In this paper, the effects of tire resonance on the non-uniformity force amplitudes are demonstrated through modeling and simulation, and the model is then verified using simulations and simulations.
Abstract: Steering wheel vibrations are frequently related to non‐uniformities of the tire/wheel system. While steering system design is a major factor in the sensitivity of the vehicle, the excitation of steering wheel vibrations is due in general to non‐uniformities of the tire/wheel system. However, tire non‐uniformities are to some extent unavoidable and result in rolling force variation at the spindle during steady state rolling. Therefore, limiting and managing these non‐uniformities is of great economic importance to tire manufacturers. The present work demonstrates the tire's role in generating non‐uniformity induced dynamic force variations due to 1st order geometric imperfections. Both analytical and numerical approaches are studied. Numerical experiments of the effects of non‐uniformities are investigated with the physics based tire model FTIRE. The effects of tire resonance on the non‐uniformity force amplitudes are demonstrated through modeling and simulation. The model is then verified using ...
14 citations
"A study on the effect of different ..." refers methods in this paper
...Dorfi [10,11] in an interesting work used the physics-based FTire model to simulate the tyre nonuniformities and showed that FTire model can be used to study the imperfections....
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TL;DR: In this paper, a mathematical model of a tire consisting of a rigid tread ring connected to a freely rotating wheel or hub through an elastic foundation which has radial and torsional stiffness was developed.
Abstract: When measuring bearing forces of the tire‐wheel assembly during drum tests, it was found that beyond certain speeds, the horizontal force variations or so‐called fore‐aft forces were larger than the force variations in the vertical direction. The explanation of this phenomenon is still somewhat an open question. One of the hypothetical models argues in favor of torsional oscillations caused by a changing rolling radius. But it appears that there is a simpler answer. In this paper, a mathematical model of a tire consisting of a rigid tread ring connected to a freely rotating wheel or hub through an elastic foundation which has radial and torsional stiffness was developed. This model shows that an unbalanced mass on the tread ring will cause an oscillatory rolling motion of the tread ring on the drum which is superimposed on the nominal rolling. This will indeed result in larger fore‐aft than vertical force variations beyond certain speeds, which are a function of run‐out. The rolling motion is in ...
12 citations
"A study on the effect of different ..." refers background in this paper
...Stutts and Sodel [4] investigated the fore-aft tyre excitation forces due to tyre imbalance....
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