Analytical determination of application point and normal reaction arm when rolling a wheel on a drum

Evaluation of the rolling resistance of car tires is now often performed on drum stands like car tests. This necessitates the study of the mechanics of interaction between the wheel and the drum in order to determine its force and kinematic characteristics, including the values and points of application of tangential and normal forces in contact with the drum. These problems can be solved taking into account that the mechanics of elastic wheel rolling on a drum is the same as when rolling on a flat rigid support surface. In this paper, from consideration of the mechanics of interaction between an elastic wheel and a drum, using the equations of power balance and force equilibrium of the wheel, the equations for determining the point of normal reaction in contact and its arm relative to the wheel axis during its rolling along one and two drums have been derived.. These dependencies have a simple form and can be applied when considering the rolling of both a single wheel and the car as a whole on a drum stand.

Download Full-text

Use of the kinematic radius in the rolling mechanics of an elastic wheel

10.36652/1684-1298-2021-5-17-27 ◽

2021 ◽

pp. 17-27

Author(s):

V.I. Kopotilov

Keyword(s):

Traction Force ◽

Rolling Resistance ◽

Kinematic Parameter ◽

Resistance Force ◽

Elastic Wheel ◽

Wheel Rolling ◽

Physical Essence ◽

Braking Force ◽

Rolling Mode

The analysis of the physical essence of the kinematic and dynamic radii of the wheel is given. It is stated that the rolling radius of the wheel is a conditional kinematic parameter that characterizes only the rolling mode of the wheel. It is not the shoulder of all longitudinal forces acting on the wheel and should not be used to determine tractive forces, rolling resistance and wheel braking forces. Specific examples are given to illustrate the inappropriateness of using the kinematic radius to determine forces and moments. Keywords: elastic wheel, rolling radius, kinematic radius, dynamic radius, arm of force, traction force, rolling resistance force, braking force, rolling mode

Download Full-text

Theoretical determination of the distribution of forces and the size of the boundaries of the contact in the interaction of the deformable drive wheel with the soil

Bulletin of the Karaganda University Physics Series ◽

10.31489/2020ph3/62-72 ◽

2020 ◽

Vol 99 (3) ◽

pp. 62-72

Author(s):

V.P. Kovbasa ◽

◽

A.V. Spirin ◽

A.V. Solomka ◽

V.Yu. Kucheruk ◽

...

Keyword(s):

Mechanical Properties ◽

Contact Zone ◽

Rolling Resistance ◽

Analytical Determination ◽

System Of Equations ◽

Deformable Medium ◽

Supporting Surface ◽

Theoretical Determination ◽

Deformable Surface

The article presents the results of an analytical determination of the forces distribution along the length of the contact curve of the driving deformable wheel on the deformable supporting surface, and also are defined the boundaries of the contact zone. The case in a flat statement of the problem is considered. The supporting surface and the surface of the deformable wheel are represented as a continuous deformable medium. The shape of the wheel in the contact zone is represented by the circle equation, which in the contact zone is expanded in a Macloran-series. By using conditions at the boundaries of the contact zone, a system of equations is obtained from which the sizes of the contact zone are determined. The solution of these equations allows one to find expressions of the sizes of the contact zone of the deformable wheel with the deformable surface, depending on the mechanical properties of the wheel materials and the supporting surface, from the geometric dimensions of the wheel and from the loads applied to it. In addition, the results of the studies allow us to determine the analytical expression of the coefficient of rolling resistance of a deformable wheel over a deformable surface, depending on their mechanical properties, geometric parameters, and the loads applied to it.

Download Full-text

Using the kinematic radius in the mechanics of elastic wheel rolling

10.36652/1684-1298-2021-4-13-22 ◽

2021 ◽

pp. 13-22

Author(s):

V.I. Kopotilov

Keyword(s):

Traction Force ◽

Rolling Resistance ◽

Clear Understanding ◽

Elastic Wheel ◽

Wheel Rolling ◽

Instantaneous Center ◽

Wheeled Vehicles

As you know, in the mechanics of a wheel with an elastic tire, both dynamic (rd) and kinematic (rk) radius are widely used. At the same time, specialists in the theory of the motion of wheeled vehicles still do not have a clear understanding of the scope of their application. Keywords: elastic wheel, kinematic radius, circumferential force, dynamic radius, wheel traction force, instantaneous center of speeds, torque, solid, rolling resistance

Download Full-text