ABSTRACT

The virtual design of steering systems requires suitable premises for predicting realistic steering rack forces. This includes the proper tire used for the parking maneuver. It is important to select the tire from a portfolio that generates the highest rack forces at the vehicle, so that the electro-mechanical dimensioning of the steering system can be safeguarded for all tires of a vehicle. To avoid time-consuming and expensive full vehicle measurements, drilling torques of tires are measured on a Flat-Trac to determine the so-called worst-case tire. However, the determined drilling torques do not correlate with the measured rack forces.

This work therefore investigates the suitability of a Kinematics & Compliance test rig converted to a tire test rig. First, it is investigated whether the wheel movements from the parking maneuver can be decomposed into their individual elements on the test bench. In addition, reproducibility studies are carried out and three different methods for determining the aligning torque under camber are presented. Furthermore, measurements for static and dynamic friction values, as well as stiffnesses and the contact patch, are integrated into the new measurement procedure. It becomes apparent that temperature and wear level of the tire play a major role in the reproducibility of the measurements. If the measurement procedure described in this paper is followed exactly, the scatter of the drilling torque can be reduced by up to 24% compared to the old procedure. For the dynamic and the static friction values, the scatter is reduced by about 17% and 22%, respectively. Stiffness scatter can be reduced by up to 16%.

With the new measurement procedure, the worst-case tire can be reliably determined. The drilling torques correlate with the rack forces and the additional tire characteristics permit finer resolution. After evaluation and interpretation, recommendations for future developments are discussed.

ABSTRACT

The tire industry still spends a considerable amount of resources on indoor and outdoor tests during the product development stage. Virtual tests provide conditions to complete this step faster, saving both money and time. Considering that life span and mileage are important issues, especially for truck tire consumers, virtual wear analyses provide valuable information that helps engineers to improve their products. This study aims to exemplify a way to predict tread band wear using the finite element method approach and Archard’s wear theory. In addition, it shows the importance of following the vehicle maintenance program as it has an impact on how long the set of tires will last. Tread wear simulation is implemented through user subroutine and adaptive meshing technique, whereas friction energy is calculated using a steady-state analysis at selected working conditions. Data collected from outdoor experiments provide the necessary information to check and validate the analysis. The impact of the lack of appropriate vehicle maintenance on tire wear is evaluated by changing some boundary conditions of the model such as load, inner pressure, and camber and toe angles. The simulation results show good agreement with the information found in the literature.

ABSTRACT

This paper aims to devise a method to obtain an empirical friction law for rubber using the Laboratory Abrasion Tester (LAT 100). The LAT 100 experiments, which aim to measure the side force at various slip angles, loads, and speeds, are carried out, followed by finite element simulation using ABAQUS. A friction law is implemented using a subroutine (UFRIC), which calculates the friction coefficient at each node on the contact patch based on contact pressure and slip velocity at the corresponding node. Coefficients of the frictional law, μ = a + b × e^−1/(α^p⁾ + c × e^−1/(β^v⁾, have been estimated by using a series of simulations along with minimizing the error between experiment and simulation side forces. The procedure followed in this paper can be used to fit friction models for rubber using LAT 100 side force experiments.

A

Ahmadi, M.: see Neumann, D., 262-284 (2023)

Ashofteh, A.

Effect of Different Road Obstacles on the Structural Behavior of a Honeycomb Nonpneumatic Tire (A. Ashofteh and A. Shahdadi), 2-17 (2023)

Assaad, M.

Rubber Comprehensive Constitutive Equation and the Prediction of Tire Temperature and Rolling Resistance (M. Assaad, T. Ebbott, B. Jiang, and G. Rebel), 162-181 (2023)

B

Bachmann, C.: see Neumann, D., 233-260 (2023)

Berger, T.

A Microsphere-Based Rubber Curing Model for Tire Production Simulation (T. Berger, S. Kim, and M. Kaliske), 82-113 (2023)

Berger, T.: see Kim, S., 39-62 (2023); see Kim, S., 63-80 (2023)

Brinson, L.: see

Comparison Between Tire Rolling Resistance Measurements on a Flat Track and a Test Drum Under Non-Steady-State Conditions

Lisa Ydrefors,

Mattias Hjort,

Sogol Kharrazi,

Jenny Jerrelind, and

Annika Stensson Trigell

Identification of Characteristic Tire Parameters for the Virtual Steering System Design

ABSTRACT

Evaluating Tire Tread Wear and Its Dependence on Tire Working Conditions by Using the Finite Element Method and Archard’s Wear Theory

ABSTRACT

Friction Law for Rubber from Laboratory Abrasion Tester

ABSTRACT

Comprehensive Grounding Performance Evaluation of Tires Based on the Analytic Hierarchy Process

ABSTRACT

Tire Science and Technology

Author Index to Volume 51 2023

A

B

Tire Science and Technology

Keyword Index to Volume 51 2023

Comparison Between Tire Rolling Resistance Measurements on a Flat Track and a Test Drum Under Non-Steady-State Conditions

Critical Plane Analysis of Surface-Proximal Fields for the Simulation of Thermo-Mechanical Wear

Enhancing Tire Model Parameterization for Rollover Simulation: A Validated Approach

Research on Fast and Efficient Virtual Sample Delivery Method of Tire Mechanical Characteristics

Prediction of the Frictional Power Distribution in the Tire Contact Patch Based on an Empirical Tire Model and an Artificial Neural Network