Study on Cornering Properties of Tire and Vehicle

1990 ◽  
Vol 18 (3) ◽  
pp. 136-169 ◽  
Author(s):  
H. Sakai
Keyword(s):  
Load Distribution ◽  
Driving Forces ◽  
Slip Angle ◽  
Inflation Pressure ◽  
Slip Ratio ◽  
Side Force ◽  
Camber Angle ◽  
Tire Wear ◽  
Main Factors ◽  
Tire Friction

Abstract This paper presents theoretical analysis on the cornering properties of tire and vehicle. First, the side force, braking driving forces and self-aligning torque on the tire are shown as functions of slip angle, slip ratio, camber angle and load. Next, the steady cornering properties of the vehicle using these tires are analyzed with the rolling conditions. Slip angle, slip ratio, camber angle and load, and forces and moments of the four tires are calculated. Effects of main factors on the above vehicle properties such as the load distribution, camber/roll ratio, front/rear drive ratio, tire size, tire wear, tire inflation pressure and tire friction are discussed.

Normalization of Tire Force and Moment Data

1993 ◽  
Vol 21 (2) ◽  
pp. 91-119 ◽  
Author(s):  
H. S. Radt ◽  
D. A. Glemming
Keyword(s):  
Surface Water ◽  
Lateral Force ◽  
Slip Angle ◽  
Inflation Pressure ◽  
Slip Ratio ◽  
Tire Force ◽  
Camber Angle ◽  
Potential Benefits ◽  
Overturning Moment ◽  
Semi Empirical

Abstract Semi-empirical theories of tire mechanics are employed to determine appropriate means to normalize forces, moments, angles, and slip ratios. Force and moment measurements on a P195/70R 14 tire were normalized to show that data at different loads could then be superimposed, yielding close to one normalized curve. Included are lateral force, self-aligning torque, and overturning moment as a function of slip angle, inclination angle, slip ratio, and combinations. It is shown that, by proper normalization of the data, one need only determine one normalized force function that applies to combinations of slip angle, camber angle, and load or slip angle, slip ratio, and load. Normalized curves are compared for the effects of inflation pressure and surface water thickness. Potential benefits as well as limitations and deficiencies of the approach are presented.

The Load Dependence of Laboratory Abrasion and Tire Wear

1970 ◽  
Vol 43 (4) ◽  
pp. 701-713 ◽  
Author(s):  
K. A. Grosch ◽  
A. Schallamach
Keyword(s):  
Contact Length ◽  
Surface Topology ◽  
Inflation Pressure ◽  
Test Procedures ◽  
Side Force ◽  
Load Dependence ◽  
Tire Wear ◽  
Modified Theory

Abstract The first outcome of this investigation is that non-proportionality between sliding abrasion and load has relatively little effect on the load dependence of tire wear, which is almost entirely governed by the load dependence of the contact length, unless the inflation pressure is very low. The modified theory on the wear of slipping wheels predicts near proportionality at constant slip between wear in crab walk and side force. This relation is useful for test procedures and has been qualitatively confirmed by experiment. The theory suggests, furthermore, the existence of a severity effect on tire wear ratings which is independent of ambient or tire temperature and is expected to affect the wear rating of different tires if road tests are carried out on test routes with radically different surface topology.

An Implicit to Explicit FEA Solving of Tire F&M with Detailed Tread Blocks

2012 ◽  
Vol 40 (2) ◽  
pp. 83-107 ◽  
Author(s):  
Zhao Li ◽  
Ziran R. Li ◽  
Yuanming M. Xia
Keyword(s):  
Test System ◽  
Mapping Method ◽  
Friction Model ◽  
Experimental Results ◽  
Slip Angle ◽  
Slip Ratio ◽  
The Road ◽  
Numerical Noise ◽  
Nonlinear Stress ◽  
Solving Strategy

ABSTRACT A detailed tire-rolling model (185/75R14), using the implicit to explicit FEA solving strategy, was constructed to provide a reliable, dynamic simulation with several modeling features, including mesh, material modeling, and a solving strategy that could contribute to the consideration of the serious numerical noises. High-quality hexahedral meshes of tread blocks were obtained with a combined mapping method. The actual rubber distributing and nonlinear, stress-strain relationship of the rubber and bilinear elastic reinforcement were modeled for realism. In addition, a tread-rubber friction model obtained from the Laboratory Abrasion and Skid Tester (LAT 100) was applied to simulate the interaction of the tire with the road. The force and moment (F&) behaviors of tire cornering when subjected to a slip-angle sweep of −10 to 10° were studied with that model. To demonstrate the efficiency of the proposed simulation, the computed F&M were compared with experimental results from an MTS Flat-Trac Tire Test System. The computed cornering F&M agreed well with the experimental results, so the footprint shape and contact pressure distribution of several cornering conditions were investigated. Furthermore, the longitudinal forces in response to braking/driving torque application in a slip-ratio range of −100% to 100% were computed. The proposed FEA solution confines the numerical noise within a smaller range and can serve as a valid tool in tire design.

Lateral Tire Forces on Wet Roads

1977 ◽  
Vol 5 (2) ◽  
pp. 75-82 ◽  
Author(s):  
A. Schallamach
Keyword(s):  
Normal Load ◽  
The Self ◽  
Experimental Results ◽  
Slip Angle ◽  
Tire Model ◽  
Side Force ◽  
Tire Forces

Abstract Expressions are derived for side force and self-aligning torque of a simple tire model on wet roads with velocity-dependent friction. The results agree qualitatively with experimental results at moderate speeds. In particular, the theory correctly predicts that the self-aligning torque can become negative under easily realizable circumstances. The slip angle at which the torque reverses sign should increase with the normal load.

Theoretical Tire Model Considering Two-Dimensional Contact Patch for Force and Moment

2021 ◽  
Author(s):  
Y. Nakajima ◽  
S. Hidano
Keyword(s):  
Finite Element Method ◽  
Shear Force ◽  
The Self ◽  
Slip Angle ◽  
Force Distribution ◽  
Two Dimensional ◽  
Tire Model ◽  
Side Force ◽  
Contact Patch ◽  
Proposed Model

ABSTRACT The new theoretical tire model for force and moment has been developed by considering a two-dimensional contact patch of a tire with rib pattern. The force and moment are compared with the calculation by finite element method (FEM). The side force predicted by the theoretical tire model is somewhat undervalued as compared with the FEM calculation, while the self-aligning torque predicted by the theoretical tire model agrees well with the FEM calculation. The shear force distribution in a two-dimensional contact patch under slip angle predicted by the proposed model qualitatively agrees with the FEM calculation. Furthermore, the distribution of the adhesion region and sliding region in a two-dimensional contact patch predicted by the theoretical tire model qualitatively agrees with the FEM calculation.

A Laboratory Method to Comprehensively Evaluate Abrasion, Traction and Rolling Resistance of Tire Tread Compounds

2007 ◽  
Vol 80 (4) ◽  
pp. 580-607 ◽  
Author(s):  
M. Heinz ◽  
K. A. Grosch
Keyword(s):  
Friction Coefficient ◽  
Laboratory Test ◽  
Rolling Resistance ◽  
Limited Range ◽  
Slip Angle ◽  
Testing Conditions ◽  
Side Force ◽  
The Road ◽  
Wide Range ◽  
On The Road

Abstract A laboratory test method has been developed which allows the evaluation of diverse properties of tire tread compounds on the same sample. The laboratory test instrument consists of a rotating abrasive disk against which a rubber sample wheel runs under a given load, slip angle and speed. All three force components acting on the wheel during the tests are recorded. By changing the variable values over a wide range practically all severities encountered in tire wear are covered. The well-known fact that compound ratings depend on the road testing conditions is verified. Most compounds are only significantly distinguishable against a control over a limited range of testing conditions. Using a road test simulation computer program based on the laboratory data shows that not only ratings correspond to practical experience but also calculated absolute tire life times do. Tests on surfaces of different coarseness and sharpness indicate that sharp coarse surfaces give the best results with road tests, which of necessity are mostly carried out on public roads of differing constitution. The abrasive surface can be wetted with water at different temperatures and hence either the friction force at a locked wheel or the side force at a slipping wheel can be measured over a wide range of temperatures and speeds. At small slip angles the side force is dominated by dynamic cornering stiffness of the compound, at large slip angles by the friction coefficient. In this case, too, good correlations to road experience exist over a limited range of testing conditions. Low water temperatures and low slip speed settings in the laboratory produce side force ratings, which correlate closely with ABS braking on the road High and higher slip speeds give ratings in close agreement with locked wheel braking on the road. A heatable/coolable disk enables traction measurements on ice and newly abrasion measurements on surfaces at elevated surface temperature. Ice surface temperatures between −5 °C and −25 °C are possible. Friction measurements show that the difference in compound rating between summer and winter compounds is maintained over the whole temperature range. New investigations show not only a differentiation between different winter tire treads qualities but also an excellent correlation between tire and laboratory results. As a new topic side force measurements on dry surfaces highlight the correlation to dry handling of tires. The tire tread compound contributes to this performance through its shear stiffness and its friction coefficient. The shear stiffness contributes to the response of the tire in directional changes. The friction coefficient determines the maximum force, which can be transmitted. A simple operation possibility for evaluation of determined side forces is demonstrated. In addition to antecedent investigations the rolling resistance of the rubber wheel can be measured over a range of loads and speeds with the slip angle set at zero. Again for these new results good correlations are achieved with practical experience. In particular, the dependence of the rolling resistance on the velocity and loads are pointed out. Ultimately a good correlation between tire test and laboratory test results was demonstrated.

Investigation of the tyre characteristics under non-steady-state conditions on the basis of road tests

2016 ◽  
Vol 231 (1) ◽  
pp. 3-15 ◽  
Author(s):  
Hubert Sar ◽  
Andrzej Reński ◽  
Janusz Pokorski
Keyword(s):  
Steady State ◽  
Computer Simulations ◽  
Dynamic Characteristics ◽  
Slip Angle ◽  
Real Motion ◽  
Side Force ◽  
The Real ◽  
Different Types ◽  
Non Linear ◽  
The Difference

This paper presents a method of identifying the dynamic characteristics of tyres for non-steady-state conditions on the basis of road measurements on a vehicle. The side force acting on the tyre is presented as a function of not only the slip angle but also the slip angle derivative (i.e. the velocity of the change in the slip angle). Hence, the influence of the manoeuvre dynamics on the tyre characteristics and the difference between the characteristics obtained for steady-state conditions and the characteristics for non-steady-state conditions are shown. Also the results of computer simulations prepared for different types of tyre characteristics are presented in this paper. It is evident from the presented graphs that applying dynamic non-linear tyre characteristics for computer simulations instead of steady-state characteristics enables us to describe the real motion of a vehicle better.

Physics of the Slipping Wheel. I. Force and Torque Calculations for Various Pressure Distributions

1969 ◽  
Vol 42 (4) ◽  
pp. 1014-1027 ◽  
Author(s):  
D. I. Livingston ◽  
J. E. Brown
Keyword(s):  
Pressure Distribution ◽  
Lateral Force ◽  
Slip Angle ◽  
Uniform Pressure ◽  
Elliptical Distribution ◽  
Side Force ◽  
Contact Patch ◽  
Pressure Distributions ◽  
Parabolic Distribution

Abstract Slipping wheel theory has been extended to predict the dependence of the lateral force and of the aligning torque on the nature of the pressure distribution over the contact patch between the wheel and the ground. Expressions have been derived for both side force and aligning torque as functions of the slip angle under: uniform pressure distribution, which applies to the behavior of an inflated membrane wheel; elliptical distribution, which describes the behavior of a solid wheel; and parabolic distribution. All appear appropriate in some respect to the actual tire.

Tire Wear at Controlled Slip

1962 ◽  
Vol 35 (5) ◽  
pp. 1342-1359 ◽  
Author(s):  
K. A. Grosch ◽  
A. Schallamach
Keyword(s):  
Mechanical Properties ◽  
Abrasion Resistance ◽  
Effect Of Temperature ◽  
Slip Angle ◽  
Wear Rates ◽  
Relative Wear ◽  
Tire Wear ◽  
Order Of Magnitude ◽  
The Absolute

Abstract Tire wear at controlled slip, as realized by setting the wheels of a trailer at a slip angle, obeys the theoretically predicted square law dependence on the slip angle if allowance is made for the effect of temperature and abrasion patterns on the abrasion resistance of the tread compound. The temperature of the tire surface and the intensity of the abrasion patterns increase with increasing slip angle; the severity dependence of the relative wear rating of any two types of tire is largely due to differences in temperature and abrasion pattern coefficients. This applies also to wear on wet roads. The order of magnitude of the absolute wear rates agrees well with the values calculated from the abrasion resistance of tread compounds and the mechanical properties of the tire.

Jackknifing of Tractor-Semitrailer Trucks—Detection and Corrective Action

1974 ◽  
Vol 96 (2) ◽  
pp. 244-252 ◽  
Author(s):  
E. A. Susemihl ◽  
A. I. Krauter
Keyword(s):  
Corrective Action ◽  
Slip Angle ◽  
Side Force ◽  
Local Linearization ◽  
Adequate Definition ◽  
Quantitative Manner ◽  
Definition Of ◽  
Real Vehicle

This paper is concerned with the detection of an incipient tractor jackknife of a tractor-semitrailer truck and with corrective action which can be taken after the onset of jackknifing has been sensed. An approach termed local linearization is used to define tractor jackknifing in a quantitative manner. Local linearization is then used to evaluate a second approach, termed side force-slip angle combination. This side force-slip angle combination is employed to study three forms of automatic corrective action that involve braking of the vehicle. The results obtained indicate that local linearization provides an adequate definition of the onset of jackknifing. The results also indicate that the side force-slip angle combination is useful in sensing the onset of a tractor kackknife. Through the use of approximations, the side force-slip angle combination can be implemented in a real vehicle—this implementation is found to require only simple measurements. The results of the corrective action study indicate that a certain anti-skid braking procedure may be effective in the prevention of an incipient jackknife.

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