Design and Experimental Validation of a Compact Vertical Tire Testing Device for Stiffness and Damping Coefficients

Abstract

Pneumatic tire stiffness and damping are key parameters governing vehicle dynamics, ride comfort, and energy losses, yet their experimental determination often relies on large, expensive test rigs or indirect vehicle-based methods. To provide a compact and cost-effective alternative suitable for laboratory and educational environments, this study presents the design, construction, and validation of a vertical tire testing device developed in Atılım University ATEV racing car program. The machine combines a modular steel–aluminum frame, a pneumatic loading system, and a rail-guided carrier with four load cells and a displacement sensor, enabling controlled cyclic loading of a mounted tire. Structural integrity of the test rig was verified using finite element analysis in ANSYS, and experimental measurements were acquired via an Arduino-based data acquisition system and processed in MATLAB. A 90/90 R16 motorcycle tire was subjected to ten loading–unloading cycles over 220 s, producing peak forces of about 1500 N and a maximum vertical deflection of 13.5 mm, with clear hysteresis loops in the force–deflection plane. The vertical tire response was modeled using a linear Kelvin–Voigt formulation, and the stiffness and damping parameters were identified via least-squares regression after low-pass filtering and numerical differentiation of the displacement signal. The resulting effective parameters, k=106 kN/m and c=14.6 kN•s/m, yielded good agreement between measured and predicted forces, as reflected by relatively small RMSE and MAE values. These findings demonstrate that the proposed device can reliably characterize tire viscoelastic behavior under low-frequency, non-rolling excitation and provide meaningful input data for simplified suspension and vehicle dynamics analyses, while offering a flexible platform for future studies involving different tire types, operating conditions, and more advanced viscoelastic models.

Keywords

• Tire stiffness
• Damping
• Vertical testing
• Kelvin-voigt model

Project Number

ATÜ-LAP-2425-02

Ethical Statement

Ethics committee approval was not required for this study because of there was no study on animals or humans.

Thanks

The authors gratefully acknowledge the support of Atılım University Technology Transfer Office (TTO) for funding this project under grant number ATÜ-LAP-2425-02. The technical assistance and laboratory facilities provided by Atılım University Automotive Laboratory are also sincerely appreciated.

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