- Pneumatic Tire Force Generation

Abstract A three-component model for a belted radial tire, previously developed by the authors for free rolling without slip, is generalized to include longitudinal forces and deformations associated with driving and braking. Surface tractions at the tire-road interface are governed by a Coulomb friction law in which the coefficient of friction is assumed to be constant. After a brief review of the model, the mechanism of interfacial shear force generation is delineated and explored under traction with perfect adhesion. Addition of the friction law then leads to the inception of slide zones, which propagate through the footprint with increasing severity of maneuvers. Different behavior patterns under driving and braking are emphasized, with comparisons being given of sliding displacements, sliding velocities, and frictional work at the tire-road interface. As a further application of the model, the effect of friction coefficient and of test variables such as load, deflection, and inflation pressure on braking stiffness are computed and compared to analogous predictions on the braking spring rate.

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Normalization of Tire Force and Moment Data

Tire Science and Technology ◽

10.2346/1.2139525 ◽

1993 ◽

Vol 21 (2) ◽

pp. 91-119 ◽

Cited By ~ 11

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.

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The Driving Severity Number (DSN) — A Step Toward Quantifying Treadwear Test Conditions

Tire Science and Technology ◽

10.2346/1.2148771 ◽

1986 ◽

Vol 14 (3) ◽

pp. 139-159 ◽

Cited By ~ 4

Author(s):

A. G. Veith

Keyword(s):

Signal Processing ◽

Ambient Temperature ◽

Lateral Acceleration ◽

Force Distribution ◽

Single Index ◽

Tire Force ◽

Test Conditions ◽

Wheel Revolution ◽

High Degree ◽

Revolution Counter

Abstract A system, called the “Driving Severity Monitor” (DSM), has been developed for characterizing tire force distribution as related to treadwear in either normal tire use or in tire fleet testing in a convoy. The system consists of an accelerometer for monitoring lateral accelerations, a wheel revolution counter, and a module for signal processing and read-out. The output of the DSM is reduced to a single index, the Driving Severity Number (DSN), which characterizes a vehicle journey. The DSN is equal to the sum of squares of lateral acceleration measured once per tire revolution during a trip, divided by the number of wheel revolutions. The DSN had a high degree of correlation (R ≧ 0.95) with treadwear in two wear programs when pavement abrasiveness was held constant. This supports the concept that the three basic treadwear components: tire force distribution, pavement abrasiveness, and ambient temperature, can be separated for better understanding of tire treadwear.

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Temperature Rise Times in Pneumatic Tires

Tire Science and Technology ◽

10.2346/1.2167221 ◽

1976 ◽

Vol 4 (3) ◽

pp. 181-189 ◽

Cited By ~ 12

Author(s):

S. K. Clark

Keyword(s):

Heat Transfer ◽

Thermal Properties ◽

Temperature Rise ◽

Thermal Equilibrium ◽

Transfer Coefficients ◽

Pneumatic Tire ◽

Heat Transfer Coefficients ◽

Idealized Model ◽

Pneumatic Tires

Abstract An idealized model is proposed for heating of a pneumatic tire. A solution is obtained for the temperature rise of such a model. Using known thermal properties of rubber and known heat transfer coefficients, the time to reach thermal equilibrium is estimated.

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Israel’s Ground Forces in the Occupied Territories

Israeli Studies Review ◽

10.3167/isr.2020.350204 ◽

2020 ◽

Vol 35 (2) ◽

pp. 37-57

Author(s):

Eyal Ben-Ari ◽

Uzi Ben-Shalom

Keyword(s):

High Intensity ◽

Force Generation ◽

Institutional Autonomy ◽

Multiple Forms ◽

The West ◽

Occupied Territories ◽

Media Monitoring ◽

Israel Defense Forces ◽

And Control ◽

Over Time

The Israel Defense Forces (IDF) routinely rotate ground forces in and out of the Occupied Territories in the West Bank. While these troops are trained for soldiering in high-intensity wars, in the Territories they have long had to carry out a variety of policing activities. These activities often exist in tension with their soldierly training and ethos, both of which center on violent encounters. IDF ground forces have adapted to this situation by maintaining a hierarchy of ‘logics of action’, in which handling potentially hostile encounters takes precedence over other forms of policing. Over time, this hierarchy has been adapted to the changed nature of contemporary conflict, in which soldiering is increasingly exposed to multiple forms of media, monitoring, and juridification. To maintain its public legitimacy and institutional autonomy, the IDF has had to adapt to the changes imposed on it by creating multiple mechanisms of force generation and control of soldierly action.

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