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This paper presents a theoretical framework to enhance the prediction of dynamic responses in complex mechanical systems, such as vehicle structures, by incorporating both translational and rotational degrees of freedom. Traditional receptance coupling methods often neglect rotational effects, leading to significant inaccuracies at higher frequencies. Additionally, approaches that implicitly include full dynamics frequently result in redundancy of generalized coordinates, especially at connection points. To address these limitations, the generalized receptance coupling method using Frequency-Based Substructuring is extended to explicitly account for rotational dynamics resulting in a refined GRCFBS approach. This extension enhances both the understanding and prediction of system responses, which are represented through the receptance matrix or Frequency Response Function. Building on Jetmundsen's foundational work, the proposed framework introduces a practical, generalized formulation that explicitly incorporates full translational and rotational dynamics at each substructure node. This explicit definition provides deeper insights into system behavior, particularly for complex interactions between substructures under weak and strong coupling scenarios at interface points. The Euler–Bernoulli beam theory is employed to model rotational behavior at critical points, yielding reduced-order and explicit receptance matrices for substructures in the coupling process. The methodology's accuracy and applicability in capturing resonance and anti-resonance modes are validated through two case studies: the coupling of two flexible subsystems and the integration of flexible and rigid components. Results are benchmarked against numerical finite element analysis, and all limitations and potential improvements are discussed. By directly incorporating rotational dynamics directly, this approach enables more reliable dynamic response predictions under multi-directional loading conditions, particularly for vehicle and machinery system design. The GRCFBS method offers a versatile and reliable tool for dynamic system analysis, with significant potential for vibration analysis over a broad frequency range. [ABSTRACT FROM AUTHOR]

Paper presents an effective technique for developing reduced-order models to predict the dynamic responses of systems using the receptance coupling and frequency-based substructuring (RCFBS) method. The proposed approach is particularly suited for reconfigurable dynamic systems across various applications, like cars, robots, mechanical machineries, and aerospace structures. The methodology focuses on determining the overall system receptance matrix by coupling the receptance matrices (FRFs) of individual subsystems in a disassembled configuration. Two case studies, one with distributed parameters and the other with lumped parameters, are used to illustrate the application of this approach. The first case involves coupling three substructures with flexible components under fixed–fixed boundary conditions, while the second case examines the coupling of subsystems characterized by multiple masses, springs, and dampers, with various internal and connection degrees of freedom. The accuracy of the proposed method is validated against a numerical finite element analysis (FEA), direct methods, and a modal analysis. The results demonstrate the reliability of RCFBS in predicting dynamic responses for reconfigurable systems, offering an efficient framework for reduced-order modeling by focusing on critical points of interest without the need to account for detailed modeling with numerous degrees of freedom. [ABSTRACT FROM AUTHOR]

Intelligent tyres have the potential to be widely used to enhance the safety of road transportation systems by providing an estimation of the road surface friction, tyre load and several other important characteristics. Since the tyre–road contact characteristics play an important role in stability and control of vehicles under severe manoeuvers, tyre interaction with the road surface needs to be evaluated in the contact patch region. In this research, a finite element model is implemented to investigate the effects of different parameters, including vehicle velocity and normal load, on the projected contact patch area. Furthermore, a tyre with a tri-axial accelerometer attached to its inner-liner is tested on different road surfaces with different contact frictions and at different loading conditions. To validate the model, the radial and circumferential accelerations obtained from the simulation are compared with the experimental results. The effects of velocity, normal load and coefficient of friction on the contact patch area are investigated and it is concluded that the circumferential component of acceleration is the key factor for estimating the tyre contact patch length. [ABSTRACT FROM AUTHOR]

Tire durability plays an important role in road transportation safety. Damaged tires can cause vehicle instability and create potential traffic accidents. To study the potential of using the intelligent tire concept for health monitoring of the tire, a computational method for defect detection in tire structure was developed. Comparing the trend of acceleration signals for the undamaged and damaged tires can reveal information about the crack length and location around the tire circumference. To accomplish this, a finite element model of the intelligent tire was developed using implicit dynamic analysis. In addition, using the data from the model, a health monitoring algorithm was developed for predicting the crack locations using the acceleration signals obtained from the tri-axial accelerometer attached to the tire inner-liner. It is observed that the radial component of the acceleration signal plays a key role in defect detection in intelligent tires. [ABSTRACT FROM AUTHOR]

Tire durability plays an important role in road transportation safety and is taken very seriously by all tire manufacturers. Defects in tires can cause vehicle instability and create catastrophic accidents. In this article, a finite element model of the intelligent tire is developed using implicit dynamic analysis and is used for defect detection. Processing and analyzing the acceleration signals, measured at the center of the tire inner-liner, for the undamaged and damaged tires, can result in detecting the crack locations around the tire circumference. Additionally, prediction models used for damage diagnosis based on optimized number and location of sensors, was developed. Several sensors located at different locations around the circumference of the damaged tire and away from the crack surface, are used in order to assess sensor location sensitivity from the crack surface. It is observed that the radial component of the acceleration signal has the highest potential to be used as the signal of choice in defect detection as compared to circumferential acceleration signals. [ABSTRACT FROM AUTHOR]

A computational model based on the multiscale progressive failure analysis is employed to provide the theoretical predictions for damage development in the cord-rubber composites in tires. Vulcanized rubber, reinforcing belts, and carcass used in tire structures cause the anisotropic behavior under different loading conditions. Steel reinforcement layers made of steel wires combined with rubber complicate the macro-scale finite element modeling of tires. This paper presents a new three-dimensional model of the cord-rubber composite used in tires in order to predict the different types of damage including matrix cracking, delamination, and fiber failure based on the micro-scale analysis. Additionally, intelligent tires have the potential to be widely used to enhance the safety of road transportation systems, and this paper provides an estimation of the effects of void volume fraction, fiber volume fraction, and stacking sequence of the cord-rubber composites on the acceleration profile of the tire measured at the inner-liner. [ABSTRACT FROM AUTHOR]

The objective of this study is to understand the influence of high frequency tire vibrations induced due to road disturbances and brake torque cycling due to anti-lock braking system (ABS) on braking performance. Under these conditions, transient dynamics of the tire play a crucial role in the generation of braking force. To implement this, a dynamic tire model was developed using a rigid ring tire and a tandem elliptical cam design for the enveloping model. This tire model is validated using experimental data obtained from high-speed cleat tests on a fixed axle. The validated tire model is then integrated with a quarter vehicle and a commercial grade rule-based ABS model to evaluate braking performance with and without a road cleat, which can provide a high frequency disturbance. Simulation results show that the presence of a I cm cleat causes large variations in wheel slip, consequently increasing the braking distance. The developed tool will help both tire and vehicle manufactures for quick and early evaluation of braking performance without computationally intensive finite element analysis (FEA) tools. [ABSTRACT FROM AUTHOR]