Tire Parameters Research Articles

Influence of Tire Parameters on Contact Patch and Axle Force Generation against Short Obstacles Using DOE Approach

Influence of Tire Parameters on Contact Patch and Axle Force Generation against Short Obstacles Using DOE Approach

Coordination control strategy of motion stability and tire slip for electric vehicle driven by in-wheel-motors

The Direct Yaw Moment Control (DYC) is a widely utilized technique for electric vehicles equipped with In-Wheel Motors (IWMs) to ensure yaw stability. However, most existing DYC studies calculate the additional control yaw moment solely based on the torque differences among the four IWMs, disregarding the nonlinear tire characteristics and wheel rotational movements. When road conditions are poor or torque changes are intense, the tire may slip, preventing it from generating the required longitudinal tire force for the desired direct yaw moment. To address this challenge, this study introduces a coordination control strategy for motion stability and tire slip in electric vehicles (EV) driven by IWMs. To enhance control performance, the nonlinear tire characteristics and wheel rotational movements are integrated into the modeling process when calculating tire forces. Additionally, a state and parameter coupling estimation algorithm is utilized to obtain feedback on tire parameters and vehicle motion states. Using these estimation results as a foundation, a coordination strategy is developed to achieve reference motion state tracking and tire slip ratio control. The Model Predictive Control (MPC) algorithm is employed to solve the control problem with constraints on both control inputs and outputs, and the estimation results are utilized to update the control model as well as provide states feedback. Simulations and experiments are conducted to validate the feasibility and effectiveness of the proposed control strategy. The results demonstrate that our proposed control strategy effectively improves vehicle stability by coordinating vehicle motion and tire slip control.

A cylindrical shell model with distributed springs for a rotating tire

In a companion paper (Vol. 248, Article 108227), we demonstrated the dependence of tire parameters on the modal characteristics of a stationary tire. For a more realistic scenario, when tire rotation is considered, the modal characteristics are veered due to centrifugal, Coriolis, and gyroscopic effects. In this paper, we study the forced vibration response of a rotating tire and also consider the effect of static load on modal characteristics. The tire tread is modeled as a cylindrical shell and the sidewall is modeled using distributed springs in axial, circumferential, and radial directions. The tire inflation pressure is accounted for, which generates pre-stresses in the tire belt in circumferential and axial directions. The material model incorporates an orthotropic composite structure of the tire with multiple stacked layers of steel belt reinforcing. The governing equations of motion of the rotating shell are derived and further reduced to the corresponding eigenvalue problem. Galerkin’s projection with orthogonal basis functions is used to obtain the natural frequencies and associated mode shapes. For the forced vibration, the tire is excited by a harmonic point load at a fixed location, and the response is calculated by superimposing the basis functions of the free vibration problem. The analytical model predictions are compared against the computation finite element (FE) model developed in ABAQUS® and experimental modal testing results. To understand the effects of rotation on wave propagation, dispersion relations were obtained, and the wave number spectrum of the rotating tire was compared with that of the stationary one. Finally, to understand the dependence of natural frequencies on tire rotation and normal load, Campbell diagrams and frequency response functions (FRFs) were obtained from the proposed model. The model shows a fairly good agreement with experimental results and FE simulations.

Analysis of tire/gripper slip forces during the handling of large off-the-road tires

Handling large off-the-road tires poses significant safety risks in surface mines, often leading to fatal accidents. This study aims to scientifically address the industry-wide knowledge gap regarding the impacts of various operational and tire parameters on tire handler gripper and tire traction performance. The specific research objectives include (i) quantifying the maximum lift force under various pad-to-tire contact conditions, (ii) identifying critical parameters influencing the point of first slip, and (iii) offering suggestions for improving tire handling operations. To achieve these goals, a portable tire handling test rig weighing 7 t was designed, constructed, and commissioned. Subsequently, in July 2021, functional performance and initial tire slip tests were conducted at the service center of Bridgestone Mining Solutions Australia in Oxley, Brisbane. Overall, 44 lifting tests were conducted on new, semi-worn, and worn Bridgestone 42/90R57 tires using a Cascade 10 t H-Series tire handler. Further, a design of an experiment matrix was formulated to test the influence of various parameters on the slip force, which is defined as the point of the first slip. The investigated parameters included tire orientation (vertical or horizontal), tread surface (dry or wet), tire wear (new, semi-worn, or fully worn), and tire handling pressure (unpressurized standalone and 0, 5, 10, 15, 20, and 30 psi for the tire and wheel set). The results revealed that to mitigate the hazard of sudden pressurized air release, tires must be preferably lifted at the lowest pressure adequate for ensuring handling performance, preventing bead-seat displacement during lifting. Furthermore, the risk of bead-seat displacement was found to be higher when lifting tires from an initial horizontal position owing to the action of shear forces on the bead seat. Considering these factors, an optimal pressure of 10 psi was recommended for lifting semi-worn 42/90R57 tires vertically under both wet and dry conditions, contingent upon the use of a concave gripper design typical of the Cascade H-Series tire handlers.

Determining vertical oscillations of front-plow tractor without support wheel

The object of this study is a tractor with a front plow without a support wheel. One way to avoid the use of ballast is to use front-mounted plows that operate under the "push" mode. As a rule, such plows are equipped with at least one supporting wheel. The presence of the latter complicates the structure of the plow and, of course, affects the degree of vertical load on the steered wheels of the mobile vehicle. With the help of the constructed mathematical model and the corresponding amplitude and phase frequency characteristics, the dynamics of vertical oscillations of the front axle of a tractor with a front mounted plow without a support wheel were investigated. Vertical fluctuations of the total force acting on the tractor from the side of the plow were considered as a disturbing influence. According to the simulation results, an increase in the vertical load of the front axle of the tractor by 600 kg causes a desired decrease in the value of the amplitude and an increase in the phase of external disturbances of the dynamic system. The higher the frequency of disturbance oscillations, the more acceptable these characteristics become. It was established that in order to improve the response of the studied dynamic system to disturbances, it is necessary to reduce the stiffness coefficient of the tires of the front wheels. In practice, this is achieved by adjusting the air pressure in the tires. The amplitude-frequency characteristics of the system almost do not change when the damping coefficient of the tires of the front wheels of the tractor is increased in the range from 1 to 3 kN·s/m, while the phase-frequency characteristics improve. This is especially noticeable at the frequencies of oscillations of the disturbing influence in the range of 0–10 s-1. The results could be used as a basis for evaluating the efficiency of tractors with a front plow without a support wheel in tillage operations. Such efficiency can be achieved under the condition of practical implementation of the recommendations proposed in this paper regarding the selection of design parameters of tires for the front wheels of the tractor

Key dynamic performance analysis of flexible spoke non-pneumatic tire for matched unmanned ground vehicles

To fundamentally improve the lifespan of unmanned ground vehicles and their internal parts, it is urgent to address the problem of tire jumping during driving, steering, or turning. This article proposes the use of flexible spoke non-pneumatic tires instead of pneumatic tires. Therefore, a three-dimensional finite element model of a certain type of pneumatic tire and flexible spoke non-pneumatic tire was constructed and the validity of the model was verified. A simulation scheme was designed to investigate the tire cushioning and lateral performance. In order to explore the degree of influence of the structural parameters of the flexible spoke non-pneumatic tire on its cushioning and lateral performance, an orthogonal experimental simulation scheme based on L9 (33) was developed. The results show that the non-pneumatic tire requires 0.006 s to recover stability after experiencing significant vibration due to passing over a bump, while the pneumatic tire requires 0.028 s. Under rated working conditions, the non-pneumatic tire is subjected to a lateral force of 285.29 N, which is 1.9 times that of the pneumatic tire’s 142.59 N. The cushioning and lateral performance of the non-pneumatic tire is most affected by the element angle α, with an impact level of over 90%. The flexible spoke non-pneumatic tire proposed in this article can effectively solve the tire jumping problem of unmanned ground vehicles during driving, while providing design ideas for improving the cushioning and lateral performance of non-pneumatic tires.

Estimation of Lateral Velocity and Cornering Stiffness in Vehicle Dynamics Based on Multi-Source Information Fusion

<div>To address the challenge of directly measuring essential dynamic parameters of vehicles, this article introduces a multi-source information fusion estimation method. Using the intelligent front camera (IFC) sensor to analyze lane line polynomial information and a kinematic model, the vehicle’s lateral velocity and sideslip angle can be determined without extra sensor expenses. After evaluating the strengths and weaknesses of the two aforementioned lateral velocity estimation techniques, a fusion estimation approach for lateral velocity is proposed. This approach extracts the vehicle’s lateral dynamic characteristics to calculate the fusion allocation coefficient. Subsequently, the outcomes from the two lateral velocity estimation techniques are merged, ensuring rapid convergence under steady-state conditions and precise tracking in dynamic scenarios. In addition, we introduce a tire parameter online adaptive module (TPOAM) to continually update essential tire parameters such as cornering stiffnesses, with its effectiveness demonstrated through DLC and slalom simulation tests. Using a dual extended Kalman filter (DEKF) observer, the article allows for joint estimation of vehicle states and tire parameters. Ultimately, we offer a cost-effective estimation method of vital dynamic vehicle parameters to support the motion control module in autonomous driving.</div>

ОБЕСПЕЧЕНИЕ УПРАВЛЯЕМОСТИ ТРАНСПОРТНО-ТЕХНОЛОГИЧЕСКИХ СПЕЦИАЛЬНОГО НАЗНАЧЕНИЯ МАШИН НА ШИНАХ СВЕРХНИЗКОГО ДАВЛЕНИЯ ПРИ ДВИЖЕНИИ ПО ДОРОГАМ ОБЩЕГО ПОЛЬЗОВАНИЯ

The results of the analysis of changes in the controllability of vehicles when driving on ultra-low pressure tires on public roads are presented. The presence of a significant influence on the reaction of a wheeled vehicle of the frequency of the control action has been proved. Such an in-dicator of the change in controllability as the delay in the angular velocity of rotation of the wheeled vehicle from the control action is proposed. The results of mathematical modeling of the effect of the parameters of ultra-low pressure wheels on the directional controllability of all-terrain vehicles are obtained. The data provided made it possible to identify the safest tire stiffness parameters (and hence the amount of air pressure) the vehicle, affecting its active safety, as well as determine the limits of their permissible modification. It has been established that in the entire range of changes in the parameters of ultra-low pressure tires, the speed of all-terrain vehicles on public roads should not exceed 50 km/h.

拖拉机轮胎在松软土壤上的牵引特性评价：仿真与试验研究

In this study, a tire-soil rolling contact model based on the finite element method was established to determine the traction characteristics of the tire on the loose soil. Considering the soil parameters and tire parameters (loads, slip, inflation pressure and tread pattern), the influence of traction characteristics of the tire was obtained, taking tire sinkage and gross traction as evaluation indexes. The correctness of the tire-soil rolling contact model was verified by carrying out the soil bin-single wheel experiments. The results of the simulation and test showed that with the increase of load and sinkage of the tire, the gross traction tended to increase, thus enhancing the tire traction characteristics. With the increase of slip, the tire sinkage and gross traction increased, and the best tire traction characteristics were exhibited at a slip of 20%. Within the rated inflation pressure, as the inflation pressure increased, the tire sinkage decreased, the tire gross traction decreased and the traction characteristics of the tire were weakened. Under simulated working conditions, the traction characteristics of the tire first increased and then decreased with the increase of the number of tire lug pairs, and 15 tire lug pairs performed best. This paper presents a further study on the interaction between tires and soil under different influencing factors, and its findings provide an effective reference for predicting the traction performance assessment of tractor tires on working roads.

Regarding the issue of aquaplaning and the interaction of a car tire with the road surface through a layer of water

Problem. The process of interaction of a pneumatic tire of a car wheel with the surface of the road surface, which is covered with a layer of water, affects the safety of the vehicle movement, therefore, the assessment of the effect of aquaplaning when writing the conclusions of the auto technical examination is an actual direction of research. The study of the effect of aquaplaning will allow forensic experts and specialists in the automotive industry to make an objective analysis and form non-subjective conclusions. Goal. The purpose of the work is to determine the design parameters and operational features of the pneumatic tire, as well as the speed of the vehicle on the process of interaction of the car wheel tire with the surface of the road coating, which is covered with a layer of water. Methodology. The approaches adopted in the work to solve the set goals are based on the theory of aquaplaning, the theory of the interaction of the pneumatic tire with the road surface, the theory of the vehicle and the laws of theoretical mechanics. Results. The obtained results of the research in the form of an analysis make it possible to assess the impact of the aquaplaning effect of a pneumatic tire on road safety. It was established that the thickness of the water layer affects the conditions for meeting the requirements established by the traffic rules, since the decrease in the height of the tire tread pattern leads to unstable contact of the tire with the road surface. Originality. The results of the study provided an opportunity to get an idea of the influence of the design parameters of tires on road safety in terms of forming the conclusions of the motor-technical examination. Practical value. The obtained results can be recommended to forensic experts when writing expert opinions and for expert research

Online tire model iterative learning considering tire relaxation behavior

Online tire model learning is of great importance in the application of vehicle dynamics related automated driving functions. Previous research mainly focuses on static tire model identification, for example, based on brush model. However, tire transient behavior, which is difficult to measure directly, plays a critical role on vehicle lateral dynamics, especially on safety-critical handling conditions. In this work, we propose a framework for online tire model iterative learning considering tire relaxation. In each steering scenario, we utilize the learning results of tire model from previous ones as initial condition. Subsequently, we implement singular value decomposition to detect whether there is enough excitation for model learning update with different simplified tire relaxation models. Meanwhile, based on these models, we also recursively calculate and compare the least squares cost function, such that the tire parameters can be robustly estimated and optimized. Furthermore, the estimated tire parameters are then fused with those from previous scenarios based on recursive average for better control application in the next steering maneuver. Experiments demonstrate the proposed online tire model iterative learning framework has similar performance with large-scale data-based offline fitting and can be applied for better predicting tire forces than those with purely recursive least squares methods.

Research on acoustic-structural coupling model and tire parameters of tire acoustic cavity resonance noise

Tire acoustic cavity resonance (TACR) noise is one kind of low-frequency and narrowband noise that particularly annoys passengers, especially becomes more prominent in electric vehicles. This paper demonstrates a numerical investigation on the TACR noise via the acoustic-structural coupling finite element model. The accuracy of this coupling finite element model is validated both by the analytic method based on the superposition theory of traveling waves and experimental modal tests of tire cavities. According to the simulated models, the influences of external factors including the inflation pressure and road load on the TACR noise are studied. Meanwhile, as the main constituent component in the tire model, the effect of belt cord is also discussed. To design the low-TACR noise tire, various design parameters of the inner contour in tire cavity are analyzed. By the orthogonal test and range analysis, it is found that the contour parameters can slightly affect the modal frequency and sound pressure of TACR noise. Among these, the curvature radius of the tire shoulder ρ 4, tire sidewall ρ 5, and half-section height H have a more obvious influence on the TACR noise than the curvature radius of the tire crown region ρ 2 and transition region ρ 3. Meanwhile, it also illustrates that increasing the curvature radius at the tire shoulder ρ 4 and reducing the half-section height H has a reduction effect on the TACR noise. This study can contribute to the design of low road noise tires.

Dynamic Characteristics of Three-Body Braking System Considering Tire-Road Friction

Abstract With the significant increase in vehicle ownership in our country, urban traffic conditions have become increasingly congested. Low-speed driving has become more prevalent, leading to more frequent instances of starting and braking. Consequently, the issue of low-speed braking flutter has become increasingly prominent. While the brake is in an open environment, the dust and particles in the air and the debris generated by the brake itself will have an impact on the braking behavior. In addition, according to the theory of modal coupling, the braking stability of the vehicle is also affected by other components. In this paper, different dynamic torsional models of braking system are established according to different braking conditions. Through numerical calculation, the influence of tire parameters, road conditions, and particles on the friction dynamics characteristics of braking system pairs is explored. The results show that the instability of the brake pair system often occurs at low speed. Different tire slip ratios, tire offset factors, and road conditions will lead to different relative motions of the braking system, but the existence of particles in the brake lining-disk interface can enhance the motion stability of the system.

Influence of tyre construction parameters on cavity noise amplification and its impact on electric vehicles

When the tyre rolls over a macro uneven road surface, it starts to vibrate which is responsible for cavity noise excitation. This excitation range typically lies between 180-250 Hz for passenger car tyres. With the rise of electric vehicles in the market, vehicle interior noise is becoming a key demand from OEMs across the globe. It is therefore paramount to understand how tyre parameters such as cavity, construction, compounds and reinforcements excite this cavity noise under tyre operating conditions such as inflation pressure, pre-load and vehicle speeds. External cavity noise reduction methods such as foam technology in tyres can help reduce this excitation. However, this also leads to other challenges such as increased product costs. This investigation therefore, shows possible solutions to minimize the impact of cavity noise amplification.

Nonlinear model predictive control for yaw rate and body motion control through semi-active and active suspensions

Active and semi-active suspensions for passenger cars traditionally enhance comfort through body control, and vehicle handling by reducing the tyre load variations induced by road irregularities. Active suspensions can also be designed to track a desired yaw rate profile through the control of the lateral load transfer distribution between the front and rear axles. This paper considers an integrated system including semi-active and active suspension actuation to control the yaw, roll, pitch and heave dynamics excited by the driving actions. To this purpose, two novel real-time-capable implicit nonlinear model predictive control (NMPC) formulations, excluding and including cost function weight adaptation, are proposed and compared with the passive vehicle, and the controlled vehicle with two combinations of skyhook and active roll control, the first based on a pseudoinverse decoupling transformation for obtaining the damping force contributions, and the second using an inverse formulation. The algorithms are assessed through an experimentally validated simulation model, along manoeuvres corresponding to sub-limit and limit handling operation, to analyse the trade-off between body motion reduction and cornering response enhancement. The results show that the adaptable NMPC configuration provides the best performance in all scenarios, also for significant variations of the main vehicle and tyre parameters.

An Energy-Oriented Torque-Vector Control Framework for Distributed Drive Electric Vehicles

The over-actuated characteristics of distributed drive electric vehicles (DDEVs) provide a flexible platform to pursue higher holistic performance. This paper proposes a dual-model predictive control (MPC)-based hierarchical framework to realize the energy saving while improving the handling stability for DDEVs. The upper layer allocates the torque vector through the front/rear axles, which can provide a high-efficiency zone for the in-wheel motors and reduce the energy consumption. The lower layer generates a direct-yaw-moment control input by differential longitudinal forces of the left/right wheels to ensure the vehicle handling stability. Considering the time-varying state variables, a linear-time-varying model-predictive-control (LTV-MPC) method is adopted to guarantee the accuracy of the model. The combined magic formula tire model is used to modify the tire parameters, including tire longitudinal stiffness and cornering stiffness. The soft constraint constructed by β-γ phase plane is introduced in the LTV-MPC to ensure the vehicle stability, based on which, a relaxation factor is designed to reduce the energy consumption due to the excessive direct-yaw-moment control inputs. The simulation and hardware-in-the-loop (HIL) test results show that the proposed control framework can effectively reduce the energy consumption for DDEVs while ensuring the vehicle handling stability.

Chemical characteristics of fine tire wear particles generated on a tire simulator

Tire wear is one of the major sources of traffic-related particle emissions, however, laboratory data on the components of tire wear particles (TWPs) is scarce. In this study, ten brands of tires, including two types and four-speed grades, were chosen for wear tests using a tire simulator in a closed chamber. The chemical components of PM2.5 were characterized in detail, including inorganic elements, water-soluble ions (WSIs), organic carbon (OC), elemental carbon (EC), and polycyclic aromatic hydrocarbons (PAHs). Inorganic elements, WSIs, OC, and EC accounted for 8.7 ± 2.1%, 3.1 ± 0.7%, 44.0 ± 0.9%, and 9.6 ± 2.3% of the mass of PM2.5, respectively. The OC/EC ratio ranged from 2.8 to 7.6. The inorganic elements were dominated by Si and Zn. The primary ions were SO42− and NO3−, and TWPs were proven to be acidic by applying an ionic balance. The total PAHs content was 113 ± 45.0 μg g−1, with pyrene being dominant. In addition, the relationship between the chemical components and tire parameters was analyzed. Inorganic elements and WSIs in TWPs were more abundant in all-season tires than those in winter tires, whereas the content of PAHs was the opposite. The mass fractions of OC, Si, and Al in the TWPs all showed increasing trends with increasing tire speed grade, but the PAHs levels showed a decreasing trend. Ultimately, to provide more data for further research, a TWPs source profile was constructed considering the tire weighting factor.

Optimization of the Tire Building Drum for Passenger Tires Using the TRIZ Methodology

Abstract This study deals with the research on the impact of the construction of a tire-building drum on the selected parameters of a passenger tire. The introductory part of the study deals with a comprehensive analysis of the production process and factors that affect the quality of the final tire product during production. The content of this analysis is also the naming of problematic parts and their subsequent influence on the resulting parameters of a passenger tire. The core of the study is an optimization design for improving the construction of the tire-building drum. The world-renowned TRIZ methodology was applied to achieve the desired improvement results. Using the TRIZ methodology, the technical system was analysed, identified problematic parts, and defined the technical and physical contradictions and proposed possibilities for their removal. The systematic approach to the solution of the task has generated options for the right solution and possible optimization by reducing the weight of individual parts of the tire-building drum. During analysis, simulations of the deformation and total stress will be available before and after optimization. The work’s conclusion describes the results of the simulation and the development process for the experimental testing possibilities of the optimized equipment. The study output is also a systematic procedure for testing the technical system, which can help designers design and optimize some parts of similar technical systems.

Calculation of normal stiffness and contact patch of ultra-low pressure tires for agricultural machinery

BACKGROUND:The impact of tires on a deformable ground surface determines not only the ability of a vehicle to move, but also the pressure on ground through the contact patch geometric characteristics. The pressure on soil is normalized and limited by the conditions for the preservation of its agrophysical properties. Therefore, when creating vehicles for various purposes for their movement or movement of their trailers on deformable ground surfaces, it is required to calculate the pressure on ground in the design process. However, currently there are no universal dependencies for calculation of the mentioned parameters of ultra-low pressure tires. This applies to both vertical and inclined tire arrangement.
 AIMS:Development and implementation of universal methods for calculation of normal stiffness and con-tact patch parameters of ultra-low-pressure tires for agricultural machinery.
 MATERIALS AND METHODS:Software products such as MS Excel, MATLAB and Curve Expert Professional were used in modeling.
 RESULTS:The universal analytical-experimental dependence has been obtained to determine the normal stiff-ness of ultra-low pressure tires, including a possible inclination of the wheel rotation axis. The dependence takes into account tire pressure, normal wheel load, an inclination angle of the rotation axis and tire geometric characteristics. The formula is obtained for determining the contact patch contour area of an ultra-low pressure tire. It helps to calculate the current pressure on ground, which should not exceed the specified value.
 CONCLUSIONS:The method for calculation of normal stiffness and contact patch parameters such as contact length, contour area and contact pressure for ultra-low pressure tires has been developed and implemented. The method is universal for all ultra-low pressure tires.

Stochastic analysis for in-plane dynamic responses of low-speed uniformity of tires due to geometric defects

Tire uniformity is defined as the dynamic mechanical characteristics of pneumatic tires due to the defects originating in tire components during manufacturing processes. These defects lead to deviations in the structural and material parameters of tires and, in turn, induce variations in the dynamic response. In this scenario, this paper proposes a probabilistic model of the low-speed uniformity analysis for predicting the impacts of the uncertainties in the geometric defects and the vertical load on the dynamic responses. The deterministic coupled rigid–flexible ring model, combined with the generalized polynomial chaos expansion theory, is developed to simulate the radial force variation due to radial run-out. In this approach, the non-uniform tire radius and the vertical load are selected as a set of random variables and are approximated by the generalized polynomial chaos expansions. The distributions of these input variables are identified from 200 measured tires by the Pearson model. A non-intrusive probabilistic collocation method is adopted to evaluate the coefficients of the generalized polynomial chaos expansions, and the selection of collocation points is also illustrated. Finally, the distributions of the radial force variation and its first harmonic due to the geometric defects and vertical loads are predicted in comparison with measurements. Moreover, the distributions of the dynamic response caused by each parameter and different variance levels are discussed and verified by the measurement data from 1130 tires.