Browse Topic: Tires

Items (3,248)

Design of a Four-Wheel Turning Tobacco Harvester Suitable for Hilly Areas

2026-99-0333

8/14/2026

To address the core requirement of “layered ripeness and non-destructive harvesting” in tobacco-growing hilly regions of China, a specialized tobacco leaf harvester was developed. Considering the challenges posed by scattered plots and complex terrain, a four-wheel steering chassis system was proposed. The platform adopts a four-wheel independent drive and steering (4WID-4WIS) configuration, powered by DC servo motors and integrated with a microcontroller-based ROS system. The resulting drive chain—comprising motors, gear reducers, and off-road tires—achieves a maximum operating speed of 0.5 m/s. A novel rotary cross-blade harvesting module was designed in conjunction with a conveyor-based transmission mechanism, enabling stratified harvesting and leaf transport. Full-condition field tests were conducted. In terms of mobility, the harvester achieved stable operation at 0.5 m/s on cement roads, 0.1–0.2 m/s in fields, and demonstrated slip-free climbing on 20° slopes. In terms of harvesting performance, the system’s adjustable modules accommodated varying plant heights; however, issues with blade grip were observed when handling irregularly slanted stalks, affecting collection efficiency. During continuous field entry and exit operations, no mechanical failures occurred, verifying the prototype’s operational stability. This study introduces an innovative combination of omnidirectional mobile chassis and stratified blade modules, offering technical support for the modernization of tobacco agriculture. Further refinement of the harvesting strategy will be pursued to enhance practicality.

Guo, Ting, Gu, Jin, Li, Wen, Tang, Xiaoming, Long, Chao, Yang, Dongchao

Comparative Analysis of CDTire Model and FTire Model in Vehicle Comfort and Durability Simulation

2026-99-0301

8/14/2026

Applicability of the CDTire tire model in vehicle handling and stability simulations is studied in this paper by comparison with the PAC2002 tire model. Based on the physical tire 245/50 R20, corresponding CDTire and PAC2002 models are established and assembled on the multibody dynamics model of an SUV. After simulating 5 handling and stability conditions, it is found that the CDTire calculation is more time-consuming compared with PAC2002, but the increased time cost does not exceed 10%. In addition, the relative errors of the 17 evaluation indices obtained based on CDTire compared to PAC2002 do not exceed 5%. Therefore, in terms of both computational accuracy and efficiency, CDTire is suitable for application in vehicle handling and stability simulation.

Gao, Fengling, Wu, Wenwen, Fei, Yuanjun

Study on Penetration Damage Characteristics of Honeycomb Non-pneumatic Safety Tiree

2026-99-0167

7/31/2026

To improve the mobility and reliability of special-purpose vehicles that are operated in extreme conditions and to minimize the influence of tire failure on the vehicle’s mobility, this paper investigates how the mechanical properties of honeycomb non-pneumatic tires are affected after high-speed impacts from external projectiles. A prototype of a network non-pneumatic honeycomb tire was initially developed, which was made of polyurethane material. The five parameter model of the Mooney-Rivlin model was selected as its constitutive relation and the experimental study was performed to validate three-dimensional stiffness simulation model for the tire. Secondly, a LS-DYNA-based finite element model was developed to describe the dynamic behaviors of the tire under an external impact at various locations (e.g. tread, single spoke plate and joints), and to investigate the influence of local damage and spoke plate fracture on the stiffness of the tire. The results indicate that the tire has better performance of resisting the impacts at small and medium levels, with the decrease of radial stiffness of the tire less than 4% after experiencing the ultrahigh load; after the spokes plate is broken, the radial stiffness of tire drops significantly by comparing with the intact tire, that is 24.17%, which has a great effect on the support performance of the tire. The findings of this work offer theoretical support and design guidelines for the structural optimization and properties improvement of NPTS.

Yao, Tuzao, Sun, Xiaowang, Zhang, Qiang, Fu, Lei, Huang, Jianbin

Comparative Analysis of CDTire Model and FTire Model in Vehicle Comfort and Durability Simulation

2026-99-0109

7/31/2026

This paper studies the applicability of the CDTire tire model in vehicle comfort and durability simulations by comparing it with the FTire tire model. Based on a physical 250/50 R19 tire, the corresponding CDTire and FTire models are developed and integrated into a multibody dynamics model of an SUV. After simulations of two handling comfort conditions and one durability condition using the CDTire and FTire models, it is found that, when FTire is used as the base case, CDTire produces a smaller relative error in vehicle comfort simulation, with a maximum of +5.6%. In the durability simulation, the relative error is larger, but the maximum value remains within ±10% at + 9.7%. Therefore, it can be concluded that CDTire is one tire model with acceptable simulation accuracy for vehicle comfort and durability.

Gao, Fengling, Wu, Wenwen, Geng, Hao

Development of Electric Vehicle Oils with High Energy Efficiency and Cooling Performance by Applying Novel Friction Modifier

2026-01-5064

7/31/2026

Improving the efficiency of electric vehicle (EV) transmissions can help to extend the driving range of EVs, and the EV oil used in these transmissions plays an important role. In this study, in order to enhance energy efficiency, we examined the effects of lowering viscosity, traction, and friction in EV oil. While friction modifiers (FMs) have been widely used as friction reduction technologies in the field of tribology for many years, we previously developed a new FM that reduces friction in drive units. We found that a combination of lowering viscosity and using the developed FM was effective for better energy efficiency. The oil formulated with the developed FM improved efficiency by approximately +0.8% to +0.9% compared to commercial EV oil. EV oil also requires cooling performance. We assumed that reducing heat generation through friction reduction would improve cooling performance and examined the effect of lowering viscosity, traction, and friction. Consequently, it was found that a combination of lowering traction and applying the developed FM is effective for reduction in parasitic heat losses. We also examined durability, which is an issue when reducing viscosity. The results suggested that the oil formulated with the developed FM had good durability for gears and bearings. Thus, we succeeded in developing an ultra-low-viscosity EV oil that has excellent energy efficiency and high cooling performance.

Nakamura, Toshitaka, Furuse, Takashi, Hasegawa, Shinji, Akahori, Shinya, Itou, Kimikazu, Sakurada, Soichiro, Akiguchi, Junnosuke

Research on Fault-Tolerant Control Strategy for Drive System Failure of Corner Module-by-Wire Chassis Vehicles

2026-01-5054

7/31/2026

As an emerging research focus, corner module-by-wire chassis vehicles overcome the limitations of traditional chassis in flexibility, cost, and development efficiency, serving as a key infrastructure in the autonomous driving era. However, their numerous actuators raise significant actuator failure risks. This paper analyzes the characteristics of such vehicles and studies fault-tolerant control for drive system failures. Firstly, a vehicle model for the corner module-by-wire chassis was established based on CarSim and Simulink. Then, a hierarchical lateral stability control strategy was designed for the non-faulty actuators: the decision control layer employed sliding mode control (SMC) and fuzzy PID control, selecting the optimal method to output additional yaw moments; the control allocation layer distributed the upper-level target yaw moments based on the vertical load of the tires, converting them into individual wheel torques to meet the constraints. For the drive system, potential fault scenarios were analyzed and their fault modes were classified. By using the non-faulty actuators for torque reconstruction, fault-tolerant strategies were designed for single-motor, diagonal dual-motor, and coaxial dual-motor faults. A co-simulation platform was built using MATLAB/Simulink and CarSim, testing the stability control strategies under three fault modes in constant-speed straight-line and double-lane change conditions. Simulation results show that the designed drive system fault-tolerant control strategy effectively maintains the vehicle’s expected dynamic performance and stability.

Zheng, Hongyu, Zhang, Tianhao, Zhang, Yuzhou

Development and Validation of a Braking Simulation Model Applied to a 6x2 Vehicle in Compliance with NBR 10966-2

2026-36-0318

7/30/2026

This study presents a comparative analysis of the braking performance of a heavy commercial vehicle under in-gear and out-of- gear conditions, combining experimental tests conducted at 60 km/h with high-fidelity computational simulation. The numerical model incorporates real engine torque, power, and motoring/braking curves, full brake system parameters, dynamic load transfer, tire–road friction characteristics, and ABS actuation. Simulation results were validated against experimental MFDD and stopping distance measurements. The simulation demonstrated a high correlation with the experimental MFDD values (5.3 vs. 5.36 m/s2 in the in-gear condition and 5.6 vs. 5.37 m/s2 in the out-of-gear condition), confirming the robustness of the model. Differences in stopping distance were attributed primarily to the real-world behavior of the ABS and to variability in the road surface friction coefficient. The study concludes that braking with the vehicle in gear provides improved longitudinal stability due to the resistive contribution of engine drag torque, which also reduces the thermal load on the service brakes. Overall, the results reinforce the essential role of simulation as a development, optimization, and certification tool for brake systems.

Junior, Getulio Soares, Canale, Antônio Carlos, de Oliveira, Sergio Henrique Fidelis, Pizzi, Rafael Fortuna

Nonlinear and Robust SDRE–H∞ Control for Brake-by-Wire under Variable Friction and μ-split

2026-36-0342

7/30/2026

This paper proposes a nonlinear and robust State-Dependent Riccati Equation (SDRE) combined with H∞ control architecture for brake- by-wire systems, specifically designed to handle severe tire-road friction variations and μ-split scenarios. The primary objective is to maximize deceleration capabilities while rigorously maintaining yaw stability, trajectory tracking, and passenger comfort through jerk limitation. Situated within the domain of active safety, this research addresses robustness against real-world uncertainties by utilizing a high-fidelity 14-degree-of-freedom vehicle model that accounts for longitudinal, lateral, and yaw dynamics, suspension-induced pitch and roll effects, and nonlinear tire behavior with explicit load transfer. To ensure near-optimal slip tracking under variable surface conditions, the system employs online friction estimation via Extended and Unscented Kalman Filters (EKF/UKF) fusing wheel and IMU data to adaptively adjust slip targets. The control strategy is bifurcated: the SDRE component manages dominant nonlinearities through state-dependent gains to prevent wheel lock-up, while the H∞ component provides robust disturbance rejection against parametric uncertainties such as mass variations and sensor noise. Control efforts are distributed via a Quadratic Programming (QP) torque allocator featuring anti-windup mechanisms and explicit saturation handling to compensate for lateral drift during μ-split braking. Validation is conducted through a Model- in-the-Loop (MIL) to Software-in-the-Loop (SIL) pipeline using scenarios including wet surfaces and panic braking. Simulation results demonstrate enhanced yaw stability and controlled deceleration profiles compared to conventional baselines, ensuring computational feasibility for automotive Electronic Control Units (ECUs).

Cubillos, Ximena Celia Méndez

On Disturbance-Aware Minimum-Time Trajectory Planning: Evidence from Tests on a Dynamic Driving Simulator

10-10-03-0026

7/13/2026

This work aims to investigate how disturbance-aware, robustness-embedding reference trajectories translate into actual driving performance when executed by professional drivers in a dynamic driving simulator. The study compares three planned reference trajectories against a free-driving baseline (NO-REF) to assess the trade-offs between lap time (LT) performance and steering effort: NOM, the nominal time-optimal trajectory; TLC, a track-limit-robust, time-optimal trajectory obtained by tightening margins to the track edges; and FLC, a friction-limit-robust, time-optimal trajectory obtained by tightening against axle/tire saturation. All reference trajectories share the same minimum LT objective with a small steering-smoothness regularizer, and are evaluated with two professional drivers driving a high-performance car on a virtual track. The reference trajectories stem from a disturbance-aware minimum-LT framework recently proposed by some of the authors, where worst-case disturbance growth is propagated over a finite horizon and used to tighten tire-friction and track-limit constraints, preserving performance while delivering probabilistic safety margins. LT and steering energy (SE) are evaluated as indicators of driving performance and steering effort, respectively, while RMS values of lateral deviation, speed error, and drift angle are used to characterize driving style. The results reveal a Pareto-like trade-off between LT and SE: NOM achieves the shortest LT, but with the highest SE, TLC minimizes SE at the expense of longer LT, while FLC lies near the efficient frontier, markedly reducing SE relative to NOM with only a minor LT increase. Removing reference trajectories (NO-REF) leads to both higher SE and longer LT, confirming that trajectory guidance improves pace and control efficiency. Overall, the findings highlight reference-based and disturbance-aware planning, particularly the FLC variant, as effective tools for training and for achieving fast yet stable trajectories.

Masoni, Matteo, Palermo, Vincenzo, Gabiccini, Marco, Gulisano, Martino, Previati, Giorgio, Gobbi, Massimiliano, Comolli, Francesco, Mastinu, Gianpiero, Guiggiani, Massimo

Simulation Analysis and Optimization Design of Rim Clamping Mechanism

2026-99-0533

7/10/2026

According to the working characteristics of the tire changer, the movement characteristics of its rim clamping mechanism are analyzed, and the complex movement structure is abstracted and simplified into four identical six-bar mechanism subunits. One of the subunits is taken as the research object, and the mathematical model of kinematic analysis is established. Using MATLAB software to simulate and analyze the motion law of each component, the mechanical characteristics of the component are analyzed. The optimization of the design parameters of the “six-bar mechanism subunit” is realized, the rim clamping mechanism becomes more stable, and the clamping force follows the diameter of the rim more closely.

Zhao, Fengqin, Zhou, Liyao, Wang, Mantong, Huo, Fengwei

Enhancement of Tractive Trafficability for a Four-Track Unmanned Amphibious Tracked Vehicle

2026-99-0578

7/10/2026

This study addresses the insufficient tractive trafficability of four-track unmanned amphibious tracked vehicles (UATV) in beach terrain by proposing an optimization strategy based on coordinated suspension height and hitch point adjustment. A mathematical model of vehicle drawbar pull was established to systematically analyze the influence mechanisms of vertical load distribution, suspension adjustment, and hitch point elevation on tractive trafficability. DEM-MBD coupling simulations revealed differentiated traction laws under sandy loam and clay conditions, particularly regarding track overlap effects. Results demonstrate that in sandy loam, rear-axle traversal over front-axle tracks reduces drawbar pull due to soil loosening, whereas track overlap enhances drawbar pull in clay through soil compaction. Nine suspension-hitch configurations were tested, validating optimization strategies: increased front-axle loading (Configuration a) in sandy loam and reduced front-axle loading (Configuration f) in clay. These configurations significantly improved tractive trafficability.

Chen, Yaoyao, Gao, Xue, Wang, Wenhao, Xu, Xiaojun

Feasibility Study on the Mechanical Adjustment of the Vibration Behaviour of a Powertrain Test Rig for Validating Longitudinal Vehicle Shuffle

2026-01-0735

7/1/2026

Vehicle manufacturers use Hardware-in-the-Loop (HiL) approaches to validate overall vehicle characteristics, including those dependent on the powertrain, at an early stage of vehicle development. A powertrain test rig is a typical example. In the specific setup, the vehicle engine and side shafts are mechanically coupled to the load machines of the test rig, eliminating the physical influence of the rims, tires and vehicle body. Adapting a specimen to the test rig changes some characteristics. This affects the specimen's vibration behaviour, making it more challenging to validate comfort-related characteristics. A particular example is longitudinal vehicle shuffle; the powertrain's first torsional natural frequency causes it. The natural frequencies of the real vehicle and device under test differ significantly, so a road-matching approach is not directly feasible. To account not only for tire-road contact but also for the missing vehicle mass, some scientific studies propose a purely model-based adjustment, without significant evidence. On the one hand, this has the advantage of flexible parameter adjustment, but on the other hand, the necessary computing technology and suitable parameterisation methods must be available. To investigate the extent to which the demand for a purely simulated adjustment is justified, this paper will consider a feasibility study that mechanically corrects for the missing vehicle influence. The method must determine the necessary target moment of inertia of real vehicles and the given one on the rig. This study presents a solution for reaching the target value. In addition, secondary constraints, such as manufacturing effort and costs, and safety aspects, must be considered. The approach should be flexible to accommodate variations in the most common vehicle and tire dimensions. Only by adapting the HiL to the target system, the actual vehicle, is it possible to perform road matching and thus validate driveability at an early stage in the development process.

Hübner, Carl, Prokop, Günther

Interpretable Tire Force Modeling for Formula Student Vehicle Dynamics and Lap Time Applications

2026-01-0762

7/1/2026

Accurate tire models are a key enabler for vehicle dynamics simulation, control design, and lap time optimization, particularly in the context of Formula Student race cars, where vehicle setups and tire characteristics differ significantly from production vehicles. State-of-the-art tire models, such as Pacejka’s Magic Formula, generally provide high prediction accuracy. However, their predefined functional structure and large number of coupled parameters are designed for broad applicability across many tire types rather than for specific racing tires. This often results in limited interpretability, nontrivial parameter identification, and unnecessary model complexity for specialized applications such as Formula Student. This paper presents a data-driven approach for deriving compact and physically interpretable tire force models using symbolic regression. The proposed method employs an intelligent tree search to systematically explore the space of mathematical expressions and identify models that optimally balance prediction accuracy and structural simplicity. In contrast to black-box machine learning approaches, the resulting models consist of explicit mathematical expressions that enable physical interpretation and efficient evaluation. The methodology is applied to experimental tire test bench data, focusing on the lateral force – slip angle relationship at constant vertical load. In a first step, the symbolic regression algorithm is utilized to derive a set of candidate mathematical expressions. These models are subsequently benchmarked against 200 independent data sets comprising various tire types and vertical loads. The evaluation reveals that the identified models approximate the measured tire behavior with accuracy comparable to, and in many cases exceeding, the Magic Formula, while exhibiting lower model complexity. The results demonstrate that symbolic regression can uncover alternative tire models that better represent the characteristics of Formula Student racing tires than conventional approaches. Owing to their compact structure and physical consistency, the derived models are particularly well suited for real-time vehicle simulations, parameter studies, and control-oriented applications in Formula Student vehicle development.

Anselment, Marcel, Borowski, Julian, Rudolph, Stephan

Design and Prototyping of a Winding Reconfiguration System for Electric Traction Applications

2026-01-0730

7/1/2026

Battery electric vehicles (BEVs) place high demands on electric drives across a wide operating range: high efficiency in customer-related driving scenarios and maximum performance in dynamic driving modes. A promising solution to this challenge is the dynamic reconfiguration of the electric machine winding configuration between series and parallel mode, enabling optimal electromagnetic properties of the drive for different operating points. This paper presents the design and prototyping of an electronic winding reconfiguration system for high-performance traction applications. The hardware prototype has been designed and built, but has not yet been tested, which is why the results are based on simulations. Unlike mechanical winding reconfiguration concepts, which have long transition times and cannot switch under load, the proposed system enables fast and safe load transitions between the winding configurations. The study describes the topology and hardware of the switching unit, including the integration of power semiconductors, the required connection assemblies, cooling concept and the control of the power electronics. A novel control strategy is presented that ensures continuous current paths during switching, prevents overvoltage in the windings and minimises torque interruptions. To this end, the active short-circuit operation of the electric drive is taken into account. Simulations show that the system achieves efficiency gains of up to two percentage points in the partial load range while maintaining its full performance. The additional losses caused by the switching unit remain low in the partial load range, ensuring a net efficiency gain. The proposed concept offers a practical approach to extending the range of BEV drives by dynamically reconfiguring the windings of the electric machine, thereby improving partial load efficiency without compromising performance.

Oestreicher, Raphael, Schneider, Jörg, von Ohlen, David, Fuchs, Patrick, Kulzer, André Casal

Experimental Validation of Frame-Dependent Gyroscopic Frequency Splitting in a Freely Rotating Tire Using Wireless MEMS Accelerometers and Scanning Laser Doppler Vibrometer

2026-01-0700

6/20/2026

Gyroscopic effects split circumferential traveling-wave resonances of rotating structures into forward and backward branches. This work first analyzes the splitting in the co-rotating (Lagrangian) frame to provide physical intuition for the evolution of the two branches with spin speed. A transformation to the inertial (Eulerian) frame is then derived, showing that the observed frequencies are shifted by a kinematic Doppler-like term that acts with opposite sign on the forward and backward waves, leading to different Campbell-diagram slopes depending on the observation frame. The resulting framework is validated experimentally on a freely rotating, unloaded tire using two complementary sensing modalities: wireless on-tire accelerometers (co-rotating view) and a scanning laser Doppler vibrometer (inertial view). A frequency-domain SVD-based identification (FDD/ODS-SVD) is used to extract poles and deformation patterns over a range of spin speeds, enabling Campbell diagrams in both frames. The application of the proposed transformation maps the co-rotating branches onto the inertial observations, yielding consistent forward/backward splitting between the two measurement systems.

del Fresno Zarza, Javier, Naets, Frank

Standardized Equivalent Tire Load Measurements Delivered by Suppliers to an OEM Enabling Consistent and Comparable Simulation Input

2026-01-0699

6/20/2026

Part- or component-level tests are commonly performed by Tiers and OEMs to investigate the NVH behavior and loading mechanisms. However, because test bench dynamics differ from those of the actual vehicle environment, correlating measured sound, acceleration and forces between bench and vehicle often proves challenging. Blocked forces offer a way to address this issue, as they provide test bench and vehicle independent load representations. This effectively enables different Tiers to deliver consistent load data, which OEMs can then use to better tune excitation and noise transmission on their vehicles. This paper focuses on 2 test bench compensation techniques, involving pure test and a simulation models of the tire to obtain accurate blocked-forces. The compensation techniques are validated on four testbenches of different companies.

Reichart, Ron, de Klerk, Dennis

Impact Test Simulation for Aluminum Casted Wheel Including Tire Properties

2026-01-5039

6/10/2026

Alloy wheels are essential safety components in two-wheeled vehicles. This study details the finite element analysis (FEA) used to simulate and evaluate the wheel and tire performance under the double mass impact load specified by the AIS-073 (Part-1) standard. The impact is carried out by dropping a striking mass along with a main mass onto the alloy wheel–tire assembly, as per the standard. The alloy wheel is modeled using a three-dimensional finite element model with elastic-plastic material behavior, and the tire is modeled with its internal elements (e.g., carcass, belt, etc.). The prediction of wheel impact failure is based on the total plastic work of the ductile fracture mechanism. The validity of results is confirmed by comparing the predicted permanent lateral rim deformation against the measured lateral deformation from a corresponding physical test.

Minz, Jai Shankar, Singh, Sanjay Kumar, Nirala, Deepak Kumar

Limit Stability Control for Corner Module Vehicles Based on Hierarchical Hybrid Game

10-10-04-0032

5/18/2026

Corner module vehicles (CMVs) achieve the decoupling of driving, braking, steering, and suspension, significantly enhancing vehicle handling potential, but under extreme operating conditions, the interactions between actuators severely constrain the improvement of vehicle handling performance. In order to mitigate conflicts between subsystems and enhance vehicle handling stability, a hierarchical hybrid game–based limit stability control method for CMVs is proposed in this article. Taking into account the handling potential of subsystems under limit conditions, a Stackelberg leader–follower game is designed by first designating Direct Yaw moment Control (DYC) as the leader and Active Rear Steering (ARS) as the follower. Subsequently, the DYC–ARS and Active Suspension System (ASS) were constructed into a non-cooperative game system, and the Nash equilibrium solution was solved through iteration. The lower-level controllers, respectively, established a tire force distribution model that minimizes the overall tire utilization rate and an active suspension force distribution model that does not affect the vehicle’s pitch, in order to enhance the safety margin of the vehicle under extreme conditions. Finally, the Hardware-in-the-Loop test results proved the effectiveness of the proposed controller.

Peng, Jinxin, Xiao, Feng, Ke, Yuan, Jin, Liqiang

SAE TOMORROW TODAY - Why Curing Motion Sickness Is Key to AV Success

135675/11/2026

Did you know that motion sickness affects 1 in 3 people? As AVs gain traction and drivers become passengers, it may be the biggest barrier to the future of autonomous mobility. With a focus on addressing the root cause of motion sickness, Motion Sync offers breakthrough solution: a haptic pre-activation system that helps passengers anticipate vehicle movement with a personalized in-cabin experience that could redefine comfort and productivity. Listen in as we sit down with Dr. Daniel Sousa Schulman, CEO and Founder of Motion Sync, to unpack the science behind motion sickness and why it's a critical issue for EVs, robotaxis, and self-driving cars. You'll learn why passengers get sick, why drivers don't, and how EVs can actually make symptoms worse. As a topic critical to the success of autonomous vehicles, it's a conversation you don't want to miss. We'd love to hear from you. Share your comments, questions and ideas for future topics and guests to podcast@sae.org. Don't forget to take a moment to follow SAE Tomorrow Today--a podcast where we discuss emerging technology and trends in mobility with the leaders, innovators and strategists making it all happen--and give us a review on your preferred podcasting platform. Follow SAE on LinkedIn, Instagram, Facebook, X, and YouTube. Follow host Grayson Brulte on LinkedIn, X, and Instagram.

Patterson, Lori

Directional Stiffness Decoupling in Meta-Wheels via Three-Dimensional Discrete Curved Spokes

15-19-01-0005

4/22/2026

Meta-wheels—non-pneumatic wheels whose performance is governed by structural geometry rather than internal pressure—offer new opportunities for directional stiffness control. Yet achieving independent tuning of longitudinal, lateral, and vertical stiffness within a single wheel architecture has remained challenging due to the inherent coupling in conventional radial and planar curved spokes. In this study, we introduce a three-dimensional (3D) discrete curved-spoke design that provides explicit geometric control through two independent parameters: the in-plane curvature angle (α) and the out-of-plane inclination angle (β). Using spoke-level and full-wheel finite-element (FE) simulations, supported by a simplified cantilever-beam analytical model, we show that these two geometric parameters govern stiffness in fundamentally different ways. The curvature angle α serves primarily as a geometric softener, reducing stiffness in all directions while maintaining a high top-loading ratio (TLR) (>92%). In contrast, the inclination angle β enables true directional stiffness decoupling: increasing β substantially raises longitudinal stiffness and decreases lateral stiffness, while leaving vertical stiffness nearly unchanged (≈1.4% variation). Compared with conventional two-dimensional (2D) spoke designs, the proposed 3D architecture achieves stiffness characteristics approaching those of pneumatic tires, particularly higher longitudinal stiffness and lower lateral stiffness, without sacrificing vertical load-bearing capacity. Moreover, the combined simulation–analysis framework provides an efficient early-stage screening tool by mapping desired stiffness ratios directly to geometric parameters, narrowing the feasible design space before full-wheel FE verification. Overall, this work demonstrates that 3D discrete curved spokes present a practical and interpretable route toward stiffness-decoupled, directionally programmable meta-wheels for next-generation mobility platforms.

Han, Heeseung, Liu, Zhipeng, Ju, Jaehyung

Hybrid Computational Tire-Sand Interaction: A Tractive Effort and Rolling Resistance Analysis

2026-01-0213

4/7/2026

This paper investigates the performance of a computational radial passenger car tire over winter road sand at different operating conditions. This study seeks to address gaps in literature by using both an experimental direct shear-strength test and then validating the same test in a Finite Element Analysis (FEA) software called Virtual Performance Solution (VPS) using a Smoothed-Particle Hydrodynamic (SPH) technique to model a winter road sand. The simulated sand was measured against physical sand data ensuring validation of the density, internal friction angle and cohesion. Once the sand was validated against physical testing data the sand was layered atop an icy road surface to understand the influence sand has on tractive effort and rolling resistance performance. With modelled and validated winter road sand and a Continental CrossContact LX Sport tire size 235/55R19 testing conditions were set up. The tire-sand interaction was simulated using a node-to-segment contact algorithm with edge treatment on a low friction surface for both the tire-road and the sand-road contact. Using testing conditions of 57 mm, 114 mm and 170 mm sand depth at 10 km/h, 50 km/h and 100 km/h and at 3.5 kN, 5 kN and 8 kN loading on a low coefficient of friction rigid road surface the tractive effort and rolling resistance were computed and analyzed. The goal of this research is to understand the influence abrasives, such as sand, have on the tractive effort and rolling resistance of vehicle tires in winter conditions. By understanding the tire-sand interaction this paper provides information on which operating condition is best suited to manage icy road conditions without compromising the environment.

Fenton, Erin, El-Sayegh, Zeinab

Sideslip Angle Estimation for Mining Trucks Based on Real-Time Cornering Stiffness Identification

2026-01-0618

4/7/2026

High-precision estimation of key vehicle–road state parameters is crucial for ensuring the accurate and safe control of mining trucks (MT), as well as for reliable trajectory tracking. Among these parameters, the vehicle sideslip angle is particularly critical for assessing and predicting lateral stability. However, its direct measurement is challenging, and its estimation typically depends on an accurate characterization of tire cornering stiffness. For MT, large variations in loading conditions (from empty to fully loaded) pose significant challenges to sideslip angle estimation due to the resulting nonlinearity and variability of tire cornering stiffness. To address this issue, a novel joint estimation framework integrating the Moving Horizon Estimation (MHE) and Square-Root Cubature Kalman Filter (SCKF) is proposed to simultaneously achieve high-precision estimation of both tire cornering stiffness for each tire and vehicle sideslip angle. In this framework, the cornering stiffness of the front, middle, and rear axles is identified and updated in real time using MHE through a forgetting-factor least squares method based on yaw rate and lateral acceleration data within a fixed-length time window. The updated stiffness is then incorporated into the SCKF for accurate estimation of the sideslip angle. This sequential process effectively establishes a coupling between the estimation of the two parameters, forming an integrated joint estimation mechanism. The proposed framework is validated on the TruckSim–Simulink co-simulation platform, and the results confirm its superior accuracy and robustness, demonstrating its potential to improve the safety and control performance of MT.

Xia, Xue, Shen, Peihong, Jiao, Leqi, Li, Tao, Chen, Huiyong, Zhao, Kun, Jiao, Leqi, Zhao, Zhiguo

A Cooperative AFS/DYC Lateral Stability Control for FWDIEV Based on Dissipative Energy Method

2026-01-0619

4/7/2026

To enhance the lateral stability of four-wheel-drive intelligent electric vehicles (FWDIEV) under extreme operating conditions, this paper proposes a cooperative control strategy integrating active front steering (AFS) and direct yaw moment control (DYC) based on dissipative energy method. A nonlinear three-degree-of-freedom vehicle model is established to analyze the evolution of the vehicle state phase trajectory. A quantitative lateral stability index is constructed using dissipative energy to accurately evaluate the vehicle’s lateral dynamics. Utilizing dissipative energy and its gradient information, a time-varying stability boundary is defined under dynamic constraints, and adaptive weighting coordination between the AFS and DYC systems is designed to achieve coordinated control of front steering angle and additional yaw moment. A feedforward–model predictive control (FF-MPC) framework is developed, in which a feedforward module generates compensation based on driver intent to improve system responsiveness, while the model predictive controller predicts real-time vehicle states and optimizes the front steering angle and yaw moment control inputs. This enables cooperative tracking of the yaw rate and sideslip angle, effectively suppressing lateral motion errors. Furthermore, an optimal torque distribution strategy is formulated with the objective of maximizing tire–road friction utilization, incorporating constraints such as tire load rate and motor output capability to prevent wheel slip and improve handling stability. The effectiveness of the proposed control strategy is validated through both CarSim/Simulink co-simulation and real vehicle tests under typical maneuvers such as high-speed double lane change on various road surfaces. Results demonstrate that the proposed method significantly reduces tracking errors in yaw rate and sideslip angle compared to conventional MPC strategies, thereby enhancing lateral stability and ensuring driving safety under extreme conditions.

Zhao, Kun, Zhao, Zhiguo, Wang, Yutao, Xia, Xue, Chen, Xi, Hu, Yingjia

Research on Vehicle and Longitudinal Tire Model Parameters Identification Based on Electro-Mechanical Brake System

2026-01-0634

4/7/2026

The Electro-Mechanical Brake (EMB) system is a novel type of brake by wire systems with independently controllable characteristics. This system aids in the decoupling analysis of the vehicle and actuator dynamics, thereby improving the accuracy of parameter identification. Therefore, this paper proposes an innovative parameter identification method for vehicle parameters and longitudinal tire model parameters, based on the characteristics of the EMB system and onboard sensors. First, based on the wind resistance and rolling resistance coefficients obtained from the vehicle coasting conditions, a decoupled constant clamping force sequence braking condition for the front and rear axles is designed by integrating the characteristics of the EMB actuator and vehicle dynamics. This approach enables the identification of vehicle and nonlinear longitudinal tire model parameters, significantly improving the accuracy of parameter identification. Next, considering the nonlinear characteristics of the longitudinal tire model, a factorial experiment is conducted to analyze the impact of the Particle Swarm Optimization (PSO) optimization algorithm parameters on the identification process from three perspectives: iteration count, computation time, and optimal function value. Furthermore, the effectiveness of three PSO variants: the Compressed Factor PSO (CF-PSO), the Adaptive Weight PSO (AW-PSO), and the Hybrid PSO (H-PSO), was investigated for identifying the nonlinear characteristics of the longitudinal tire model. Finally, through data simulation and real-vehicle experiments on both high-adhesion and low-adhesion roads, the effectiveness and accuracy of the proposed vehicle parameter and longitudinal tire model parameter identification method based on EMB system characteristics are verified through a comprehensive evaluation of multiple indicators, and the method’s validity is further confirmed using data backfill and model benchmarking.

Huang, Jiayi, Cheng, Yulin, Zhuo, Guirong, Le, Qiao, Wei, Wei, Shu, Qiang

Methodology for Generating Off-Road Tracks for Powertrain Simulation of Off-Road Passenger Vehicles

2026-01-0275

4/7/2026

For off-road driving, particularly on steep grades and over barriers, the engine torque is a key design criterion of off-road vehicles. In conventional powertrains with combustion engines, mechanical all-wheel-drive systems combined with differential locks are used to distribute the torque demand between the front and the rear axle based on wheel-specific traction. With the growing market share of electric powertrains, off-road applications are becoming increasingly relevant for electric passenger cars. In comparison to conventional powertrains, electric all-wheel-drive configurations do not have a mechanical torque transfer between the two axles. If one axle experiences low traction, the second axle can rely on its own torque capability only. Transfer of unused torque of the slipping axle to the other one is not possible. The challenge, therefore, is to specify the right torque requirements for each axle for off-road driving while avoiding over-dimensioning and high powertrain costs. The torque requirements must be defined in the very early stages of development, when real-world measurements are not available. As a result, these definitions must be based on simulation. This paper presents a simulation approach to address this engineering challenge. A key aspect is the modeling of the representative off-road track as input for the simulation. A method of track generation was developed by using real vehicle measurement data from off-road tracks, combined with GPS and road information. The virtual track modelling process was designed to match the overall torque behavior observed in both simulation and measurement to confirm a validated and trustful simulation approach. The validation of the approach will be shown.

Martin, Michael, Winkelheide, Jonas, Hartmann, Lukas, Sturm, Axel, Henze, Roman

Modelling and Analysis of Rolling Truck Tire over Dry and Snow-Covered Surfaces Using Advanced Computational Techniques

2026-01-0591

4/7/2026

This paper presents a novel approach to modelling and analyzing a 315/80R22.5 sized truck tire running over dry and snow-covered surfaces. The tire is modelled using Finite Element Method (FEM) in ESI Virtual Performance Solutions (VPS) software. The tire model consists of various parts representing the tread, under tread, carcass, sidewalls and beads in addition to the rim. The tire model is then verified in both static and dynamic domains against experimental data. The experimental results were conducted over a dry surface at a high-speed test track in Hällered, Sweden, at a constant travelling speed of 80 km/h, and a constant vertical load of 26 kN with sensors depicting both temperature and inflation pressure changes throughout a 40-minute run. A tire temperature model is developed, and the simulation results are correlated with the measured temperature of the tested tires. In addition, the rolling resistance variation with speed, temperature and inflation pressure is predicted and analyzed. The road is then simulated with a covered snow layer using Smoothed-Particle Hydrodynamics (SPH) technique and calibrated using both pressure-sinkage and shear-strength tests. The simulation results of the tire-covered snow road interaction provided comparable data against published literature with regards to temperature impacting measured rolling resistance, having a higher effect than the longitudinal speed of the tire as per the experimental data. The main objective of this paper is to emphasize the importance of computer simulation techniques to predict a truck tire temperature-dependent rolling resistance coefficient on both dry and snow-covered roads at various operating conditions.

Opatha, Dillon, Oijer, Fredrik, El-Sayegh, Zeinab, El-Gindy, Moustafa

Experimental Validation of a Multi-Row Tapered Roller Bearing Analytical Model for Relating Preload to Frequency Response Characteristics

2026-01-0008

4/7/2026

Roller bearings are used in many rotating power transmission systems in the automotive industry. During the assembly process of the power transmission system, some types of roller bearings (e.g., tapered roller bearings) require a compressive preload force. Those bearings' rolling resistance and lifespan strongly depend on the preload set during the installation process. Therefore, accurate setting of the preload can improve bearing efficiency, increase bearing lifespan and reduce maintenance costs over the life of the vehicle. A new method for bearing preload measurement has shown potential for both high accuracy and fast cycle time using the frequency response characteristics of the power transmission system. An open problem is experimental validation of the multi-row tapered roller bearing analytical model. After validation, the analytical model can be used to predict the assembled system damped natural frequency for a desired bearing preload. This work presents the experimental validation of the analytical model including the experimental test stand, test method, test results and comparison to analytical model. The developed test stand represents an automotive pinion shaft/gear as might be found in a rear axle and can be mounted either vertically or horizontally to simulate assembly and operational positions of the axle and to consider the effects of gravity. To measure bearing preload, the test stand is instrumented with a load cell, and each shaft has strain gages installed. Multiple accelerators are used to measure the system frequency response to an impulse provided by a modal hammer. For this work, three different bearing pairs in back-to-back configuration are tested at seven different preload values. The analytical model is evaluated using the same bearing designs and the preloads measured from the test stand. Results from the analytical model are compared to experimental results to validate the analytical model.

Gruzwalski, David, Mynderse, James

Impact of Instantaneous Center of Rotation Variability on Path Planning and Performance of Park Assist Systems

2026-01-0053

4/7/2026

Parking assist systems are among the most widely adopted driver-assistance features in modern vehicles. A key component of these systems is the path planning module, which ensures accurate vehicle alignment within a parking slot while satisfying various constraints such as maintaining slot centering, avoiding collisions in confined spaces, minimizing maneuver count, and achieving the shortest feasible path. Multiple path generation techniques—such as geometric, polynomial-based, and search-based methods—have been developed to enable safe and efficient parking maneuvers. However, most of these approaches rely on the simplifying assumption that the vehicle’s instantaneous center of rotation (ICR) is fixed, typically located on the non-steering axle. In practice, the ICR is not constant and can vary significantly across vehicles due to several physical and kinematic factors, including steering geometry, tire slip characteristics, suspension configuration, and weight distribution. Neglecting these variations can introduce trajectory inaccuracies, reducing the precision and reliability of automated parking systems. Although prior studies have explored estimation methods for the instantaneous center of rotation (ICR), limited research has examined how variations in the ICR influence overall parking performance. This paper addresses this gap by investigating the impact of ICR variation on path generation and motion control accuracy in parking assist systems. A simulation-based study using an SUV-class vehicle model is conducted to evaluate system behavior across diverse parking scenarios. The results demonstrate how ICR assumptions affect path precision and overall parking accuracy, providing insights to enhance path planning and control algorithms for real-world applications.

Awathe, Arpit, Patanwala, Abizer, Jain, Arihant, Varunjikar, Tejas

Simulation Study on a Neural Tire Model Based on Grouped Feature Learning

2026-01-0645

4/7/2026

The tire model is a crucial component in the design of the K-characteristic of FSAE racing car suspensions, and directly influences the achievement of maximum cornering lateral force. Not only do the slip angle, vertical load, tire pressure, and camber angle affect the mechanical characteristics of the tire, but temperature is also an important influencing factor when FSAE vehicle tires operate at high speeds. However, the modeling process of traditional tire models based on temperature characteristics is often very complex. The FSAE tire test code (FSAE TTC) already has a large amount of official sample data, which provides a basis for data-driven neural network models. This study implemented a hybrid modeling methodology, constructing two cascaded feedforward neural networks that combine the physical interpretability of the Magic Formula tire model with the nonlinear approximation capabilities of neural networks. The first network model uses slip angle, vertical load, tire pressure, and camber angle as input features, while the second uses tire temperature, ambient temperature, and ground temperature. The first network model simulates the magic formula model of the tire, and the second fine-tunes the lateral force, aligning moment, and overturning moment based on temperature characteristics. It prevents secondary input features (such as temperature) from being completely dominated by primary input features, facilitating the explanation of the influence of the two feature groups on tire characteristics. The accuracy and robustness of the model are suitable for the engineering requirements of FSAE. During the Formula Student China competition, based on on-track measured data, the tire model was co-simulated with VI-CarRealTime to quickly calculate the tire pressure required to achieve maximum lateral force. This effectively saved practice time before the race and helped the team achieve a third-place finish.

Liu, Xiyuan, Wang, Shenyao, Li, Mingyuan, Huang, Jiayu

Backward Fuzzy Driving Control for 6×4 Off-Road Vehicles

2026-01-0148

4/7/2026

Off-road autonomous vehicle systems must be able to operate across unstructured and variable terrain while avoiding obstacles. This presents significant challenges in vehicle and control system design, especially for less conventional platforms such as 6×4 vehicles. While forward driving autonomy has developed and matured in recent years, effective reverse navigation remains an under-explored area of vehicle co-design. Reversing 6×4 vehicles have limited rear steering authority, an extended wheelbase, and asymmetric traction, which introduce complex dynamics into any control system that is used. To address this need, a robust and experimentally validated fuzzy logic control architecture for 6×4 reverse navigation was developed during the course of this project. This architecture incorporates both near-field and long-range path data with adaptive outputs controlling steering and velocity based on a rule base that covers the whole vehicle state space. This method has low computational cost and is robust to terrain changes, wheel slip, and actuator lag. To accomplish this, the controller coevolves with the vehicle design parameters, making this an effective co-design strategy. The vehicle design constraints are embedded into the controller through constraint-aware membership functions and rule tuning, reducing the need for terrain-specific calibration. The architecture is modular and scalable across numerous similar platforms, supporting rapid reconfiguration and vehicle design exploration for future autonomous off-road vehicles such as those used in expeditionary environments.

Dekhterman, Samuel R., Sreenivas, Ramavarapu S., Norris, William R., Patterson, Albert E., Soylemezoglu, Ahmet, Nottage, Dustin

A Study of Tire Grip Performance Evolution under Dry, Wet and Snow Roads with Tire Wear

2026-01-0589

4/7/2026

This study focused on investigating how tire grip performance on dry, wet, and snowy road surfaces varied with the different level of tire wear. New, 50% worn, and end-of-life tires were prepared following worn tire preparation standards. Additionally, worn tires obtained under real driving conditions in the market were used. Tire grip performances on dry, wet and snowy roads were characterized respectively by using an indoor flat belt machine, an outdoor trailer, and a specially designed snow truck. The results demonstrated an evolution of grip performance as a function of tire wear. The study identified differences in impact between worn tire preparation methods —real driving versus artificial—particularly on snowy road surfaces. Furthermore, the effects of tire stiffness, reduced tread depth, and tread surface roughness of worn tires were investigated for each type of road surface. The objective of this study is to enhance the understanding of tire behavior throughout its lifecycle to enable more sophisticated tuning of Advanced Driver Assistance Systems (ADAS) and chassis control systems, thereby improving vehicle driving safety and performance.

Kim, Changsu, Saito, Yoshinori

Advanced Wheel Attachment Loosening Identification through Algorithmic Gear Error Analysis and Probabilistic Assessment

2026-01-0590

4/7/2026

At present, tire failures directly affect road safety, and the number of incidents caused by them is gradually increasing. Examining wheel attachment loosening on time is vital for vehicle safety. Tire-related incidents not only put people in peril but also have a detrimental effect on the economy. Therefore, the goal of this research is to develop a new and effective method for identifying wheel attachment loosening. A novel gear error reduction approach, distinct from traditional methods, combines advanced computing and probabilistic analysis. This paper involves three key components: extracting looseness eigenvalues, calculating ring gear errors, and computing the tire loosen probabilities. Gear errors derived from the Kalman filter and adjusted for speed, eigenvalues were calculated, and a tire loosening probability analysis was performed. Real-car trials across speeds and roads confirm its accuracy and reliability. This technology can improve automotive safety and maintenance, reducing accidents, claims, and pollution. It also fits autonomous and smart cars, where tire monitoring is key.

Liu, Jianjian, Zhang, Zhijie, Wang, Zhenfeng, Ma, Guangtao, Shi, Meijuan, Liu, Jing, Zhao, Binggen, Lu, Yukun

Integrated Effects of Suspension Geometry and Tire Pattern Design on Vehicle Pull Reduction under Acceleration in High-Performance and Electric Vehicles

2026-01-0593

4/7/2026

Vehicle pull under acceleration is a phenomenon commonly observed in high-performance vehicles and electric vehicles (EVs), primarily arising asymmetric driveshaft angles, drivetrain architecture, and suspension geometry. In addition to these mechanical factors, tire characteristics, particularly the tire lateral force generated at the contact patch, significantly influence this effect. The lateral force is intricately tied to the dynamics of the contact patch and the geometric design of the tire tread pattern. This study investigates the relationship between tread pattern geometry and vehicle pull under acceleration, emphasizing the role of tire lateral force variations. By employing finite element (FE) simulation, lateral force response variations (dfy/dfx) resulting from tread block deformation were analyzed. Based on these simulation, a robust analytical methodology for tread pattern evaluation and optimization was established. The developed tread pattern characteristic parameter was validated through a thorough comparison between physical testing and FE simulation results, demonstrating high consistency. Vehicle-level testing further confirmed that the application of the optimized tread pattern design significantly reduced vehicle pull under acceleration. Moreover, performance criteria for tire lateral force were defined based on the maximum torque and output requirements of high-performance and electric vehicles. The study concludes that implementing the developed tread pattern characteristic parameter enables the design of tires with enhanced resistance to vehicle pull under acceleration. Such advancements are poised to enhance steering stability, handling performance, and overall safety in vehicles with high torque outputs, especially EVs and high-performance models.

Yoon, Youngsam, Jang, Dongjin, Kim, Hyungjoo, Lee, Jaekil

Wind-Tunnel Investigation of Snow/Ice Drag on a 30%-Scale DrivAer Model

2026-01-0604

4/7/2026

Wind-tunnel tests were conducted using a 30%-scale DrivAer model, in estateback and notchback rear-geometry configurations, to investigate aerodynamic performance changes associated with snow and ice buildup on passenger vehicles. Around 20 snow/ice accumulation patterns were tested, at a Reynolds number of 2.8 × 106 based on model wheelbase, for each of the notchback and estateback variants. 5 additional patterns were tested on the estateback with roof-rack support bars. Snow accumulation was modelled with foam, while ice accumulation was simulated with aluminum tape hand-formed to the desired shape. A simulated full-scale snow thickness of 58 mm on the hood, roof and trunk increased the wind-averaged drag coefficient by 16% for both model variants. With 90 mm of snow, the drag of the estateback variant increased by 19%. Drag changes increased with, but were not proportional to, snow thickness. Chamfered front and rear edges, representing windblown shapes, reduced the drag penalty compared to square-edged snow models. The largest drag increases, of 18% and 20%, respectively, for the notchback and estateback configurations, were due to simulated patchy snow and ice on multiple surfaces. Localized ice/snow patches sometimes caused stronger increases in drag than a similar or larger volume of precipitation elsewhere. Critical surfaces include the A and aft-most (C/D) pillars, the lower-front corners, the leading-edge of the hood and the leading- and trailing-edges of the roof. Simulated snow and ice at more upstream positions often caused higher increases in drag than accumulations further downstream. Drag and base pressure were more likely to be correlated for changes closer to the rear of the model. Some snow/ice patterns were found to increase side force and rolling moment in crosswinds, or to increase lift and change the pitching moment, potentially affecting vehicle stability and traction. The results are intended to support additional studies that will examine the impacts of snow/ice accumulation on fuel/energy use and safety.

de Souza, Fenella, McAuliffe, Brian

Comparative Analysis of Flux Linkage Characterization Methods for Automotive Permanent Magnet Traction Motors: A Critical Review and Performance Evaluation Framework

2026-01-0441

4/7/2026

Accurate flux linkage characterization is essential for the design, control, performance and efficiency optimization of permanent magnet (PM) traction motors in automotive applications. Precise knowledge of flux linkage across varying load, speed, and temperature conditions directly impacts torque production, field-weakening capability, overall drive system efficiency and torque security. This paper presents a critical review and classification of flux-linkage characterization methods, encompassing offline laboratory mapping, standstill signal injection, self-commissioning inverter-only routines, and online real-time estimation. Each method exhibits distinct trade-offs in terms of accuracy, robustness to inverter nonlinearities, temperature adaptability, cost, and scalability for production and in-vehicle use. With the increasing complexity of automotive traction systems, understanding these trade-offs is crucial for optimal motor design and control. To enable systematic comparison, a performance evaluation framework is introduced based on key performance indicators (KPIs), including accuracy (below base speed, field weakening, and regeneration conditions), robustness to stator resistance variations and inverter nonlinearity, thermal adaptability, test complexity, time efficiency, cost, and applicability across the motor development lifecycle. These KPIs were selected based on their direct impact on motor performance, manufacturability, and suitability for various stages of automotive traction motor development, ensuring that analytical, dyno testing, and in-vehicle considerations are addressed.

Khan, Ahmad Arshan, Haddad, Reemon, Kim, Jay, Hermann, Justin, Mohamadian, Mustafa

Development of a Tire Blowout Experimental Platform for Dynamics and Control Validation

2026-01-0202

4/7/2026

Tires are critical to vehicle dynamics, transmitting traction, braking, and cornering forces to the road. A tire blowout, the sudden and rapid loss of inflation pressure due to puncture or structural failure, can cause severe instability, rollover, or collisions. Understanding vehicle response during blowout events is essential for developing robust safety systems and control strategies. Earlier developed simulation models are used to study and understand vehicle behavior during blowouts, but there is a lack of on-road testing platforms to validate these models experimentally. In this paper, an experimental platform integrating a tire blowout device and an instrumentation system has been developed to address this gap. The blowout device consists of multiple solenoid valves mounted on the wheel surface and powered by a 12V power supply. All valves can be triggered at the same time using an RF remote, producing rapid and synchronized deflation. As an extension of this implementation, an Arduino-based actuation system is being developed for individual valve actuation and custom deflation profiles. The instrumentation system includes GNSS, IMU, and CAN-based data acquisition for vehicle dynamic variables. Furthermore, outriggers will be installed on the vehicle to ensure safety during testing. Unlike prior devices that use single valves with external pneumatic hoses and laboratory-only operation, the proposed platform is compact, lightweight, and field-deployable due to its integration of multi-valve actuation, custom deflation control, outrigger-based safety measures, and instrumentation. The developed platform enables safe, repeatable, and full-scale on-road blowout testing within required timeframes, providing a novel framework that bridges simulation and real-world validation.

Kanthala, Maha Vishnu Vardhan Reddy, Krishnakumar, Ashwin, Lin, Wen-Chiao, Chen, Yan

A Dataset for Visual Classification of Flat Tires

2026-01-0152

4/7/2026

Flat tires represent a common yet serious issue in vehicle safety, leading to compromised control, increased braking distance, and potential rim or structural damage when undetected. Conventional tire pressure monitoring systems (TPMS) rely on embedded sensors that can fail, incur high replacement costs, and are not always equipped in older or low-cost vehicles. To address these limitations, this study presents a comprehensive visual dataset for flat-tire classification using computer vision and machine learning techniques. The dataset comprises 600 labeled images—300 flat-tire and 300 non-flat-tire samples—collected from diverse vehicle types, lighting conditions, and viewpoints. This dataset is designed to support the training and benchmarking of lightweight edge-AI models suitable for real-time deployment on embedded platforms. A set of supervised learning models were evaluated. Results demonstrate that visual-based classification provides a cost-effective and scalable pathway toward automated tire health monitoring and contributes to safer and more sustainable intelligent transportation systems.

Gunasekaran, Aswin, Govilesh, Vidarshana, Challa, Karthikeya, Maxim, Bruce, Shen, Jie

Measurement of Light Truck Tire Operating Deflection Shapes Using Scanning Doppler Laser Vibrometry: Issues and Insights

10-10-02-0010

2/10/2026

As internal combustion engines are replaced by quieter electric motors in ground vehicles, noise and vibration sources aside from the powertrain have become relatively more important. This is especially true of tires. Measurement of the dynamic vibratory characteristics of tires is critical to understanding their influence on the noise and vibration performance of vehicles, both outside the vehicle body and inside of it. In this work, the normal modes and operating deflection shapes of a Yokohama Geolander A/T light truck tire are measured using traditional modal analysis techniques as well as a non-contact Scanning Laser Doppler Vibrometry (SLDV) approach. Boundary conditions including free, fixed, loaded, and rotating are implemented to the tire and investigated. Rotating conditions are accomplished in a physical chassis dynamometer environment, with the measured tire mounted on the front axle of a Chevrolet Silverado 1500 pickup truck. Modes of vibration and associated natural frequencies that are measured in all four boundary conditions, including steady-state rotation, are reported and illustrated. Results of the study show that operating deflection shapes of a rotating light truck tire can be measured on a chassis dynamometer using SLDV, assuming the tire is undergoing steady-state rotation, but certain disadvantages in the dynamometer environment make the measurement procedure challenging. Specific concerns such as tire rotating speed consistency and sufficient spatial and frequency resolution of the measurements are delineated in this work. Moreover, practical recommendations for measurement of rotating tire operating deflection shapes using a SLDV are included, and a comparison with the Digital Image Correlation (DIC) method of measurement is presented.

Bastiaan, Jennifer M., Chauda, Gaurav, Baqersad, Javad, Gupta, Arjun, Dhami, Kevalya

Vibration Dynamics of a Half-Car Model Considering Tire–Road Separation

02-19-04-0021

2/9/2026

The vibrating half-car model is used to represent the dynamic behavior of a truck’s dependent suspension system, capturing four degrees of freedom. This research investigates time and frequency responses of vibration behavior of half-car model with possible tire–road separation. This investigation is significant because all previously reported analyses based on the tire-road attachment were incorrect, particularly regarding the tire-road separation phenomenon. The differential equations are extended to enhance the accuracy of the model, incorporating tire–road separation conditions for both wheels. A numerical approach is applied to simulate the vertical and roll dynamics of the system under the separation assumption. The simulation results are validated through experiments conducted using ADAMS View software. Integrating the tire–road separation into the model results in dynamic responses that closely reflect real-world behavior. These findings provide valuable guidance for designing more effective suspension systems and for developing control strategies aimed at reducing rollover risk and enhancing lateral stability.

Nguyen, Quy Dang, Jazar, Reza

Dynamic Stability Enhancement during Emergency Obstacle Avoidance under Inappropriate Driver Operation

10-10-02-0015

2/2/2026

In response to the decline in vehicle stability and the resulting safety risks caused by inappropriate driver operations during high-speed emergency obstacle avoidance, a human–machine cooperative control strategy based on driver operation recognition is proposed. The strategy establishes a vehicle controllability boundary by integrating real-time driver inputs with tire adhesion limits, enabling dynamic evaluation of the influence of operations on system controllability and identification of potential inappropriate operations. On this basis, a control authority allocation mechanism is developed, capable of adaptively adjusting to vehicle states and driver operations. By combining road boundary constraints with vehicle stability envelope constraints, the strategy dynamically regulates the steering angle, ensuring vehicle stability while retaining the driver’s effective intentions as much as possible. Unlike conventional path-tracking or single-envelope control approaches, the proposed method achieves early identification and proactive mitigation of instability risks induced by inappropriate driver operations, thereby reducing associated safety hazards. To validate the effectiveness of the strategy, two representative scenarios, double lane change and curve avoidance, were designed. Simulation and driver-in-the-loop experiments demonstrate superior performance in terms of vehicle stability, human–machine cooperation, and safety, achieving a higher level of coordinated control and performance balance. The findings provide new insights into the design of human–machine cooperative control strategies under extreme conditions, contributing to enhanced fault tolerance of intelligent driving systems against inappropriate driver operations and improved driving safety.

Liu, Yangyi, Zhou, Bing, Wu, Xiaojian, Jiang, Xiaokun, Cui, Qingjia

Determining Optimal Suspension & Body in White Mountings to maximize Off-Road Capability of Passenger Vehicles

2026-26-0098

1/16/2026

The automotive market trend is shifting more and more to SUVs and crossovers. This, therefore, means increasing consumer demand for off-road abilities in passenger vehicles. While dedicated off-road platforms provide a path to performance robustness, getting the same level of functionality out of a passenger vehicle with minimal architectural changes proves to be a great feat for engineers. One highly critical performance determinant in the domain of off-road ability is wheel articulation, it requires independent movement capacity of the wheels to keep contact and stability over uneven terrain. Traditional articulations found in passenger car suspensions—created for comfort, packaging, and on-road dynamics—are limited by suspension geometry, damper alignment as well as compliance setup. Damper side loads- were not considered a significant factor in suspension systems that are operating within their original intended design envelope for on-road use. However, when the vehicle is taken off-road, extreme conditions lead to lateral forces during an unseated exaggerated wheel travel, these can result in seal degradation as well as rod bending increasing friction (stiction) leading ultimately to damper failure. Seal durability and general component integrity are not the only issues increased side loading will decrease articulation reduce traction and degrade ride quality during severe terrain inputs. Articulation- is essentially a measure of flexibility in the suspension which directly controls off-road performance characteristics. With limited articulation there is wheel lift traction loss and increased chassis contact. A major limitation to achieving full articulation is damper side load-the perpendicular force to the damper shaft created from angular misalignment in suspension travel. This also increases the compressive stress on the damper rod. Therefore, an optimization of the rod diameter, length, and material is required. The Ramp Travel Index (RTI) is a means of expressing articulation by using the measure of ramp height that can be attained by a vehicle climbing with one wheel while maintaining contact with others. A high RTI indicates good off-road capability. There exists an interrelationship between suspension geometry, damper side load characteristics, and axle alignment in determining off-road performance; this paper proposes an optimization guideline to overall improve wheel articulation specifically for passenger vehicles through these parameters: wheel travel, suspension hard points, and damper mounting orientations.

Siddiqui, Arshad, Iqbal, Shoaib, Dwivedi, Sushil

Digital Rack Load Estimation Methodology to Optimize Motor Sizing for Electric Power Steering

2026-26-0383

1/16/2026

Rack load estimation during the pre-design stages is critical for the calibration of steering systems, particularly in achieving the desired steering feel and optimizing assistance strategies in Electric Power Assisted Steering (EPAS). Conventional approaches often depend on physical vehicle testing or simplified empirical equations, which may be time-consuming or lacks the fidelity required for early-stage analysis. This paper presents a 1D simulation strategy to address limitations from conventional approaches. The proposed rack force estimation model is based on multi-physics analytical equations that calculate tire-road friction forces and the resulting moments about the steering axis, delivering a physics-based yet computationally efficient solution. The rack force estimation model is further extended into EPAS system model by incorporating Direct Current (DC) brushed motor model. The rack force estimation model is validated against physical test data which demonstrates a high level of accuracy. Finally, the EPAS motor sizing strategy is discussed to obtain the optimum motor size. The proposed simulation based approach enables engineering teams to make informed design decisions and optimize steering system behavior before physical prototypes are available.

Adsul, Sourabh, Iqbal, Shoaib

Optimizing Tire NVH Performance in Electric Vehicles: A Comprehensive Approach Using Benchmarking, Simulation, and Validation

2026-26-0605

1/16/2026

The present study enumerates the effectiveness of using Foam-inside Tyres (FIT) for attenuating the in-cabin noise due to tire-road interaction in Internal Combustion Engines (ICE) converted Electric SUVs (E-SUV). Due to the elimination of the ICE Prime movers in (E-SUV), the Tyre booming, Tyre cavity, and rumbling noise in the structure-borne region are significantly audible in the driver’s & passenger's ears globally for E-SUVs. Foam tyres reduce tyre cavity resonance. However, the effectiveness of the acoustic foam is predominant between 180 to 240 Hz only. In the present study, In Cabin Noise (ICN) measurement was completed on the comfort testing track, and the results of structure-borne in-cabin noise up to 500 Hz were analysed. These measurements identified the vehicle in-cabin sensitive frequencies, which are affected by the tyre and wheel assembly. To analyse the contribution of the Tyre design parameters and to predict the ICN performance in the whole vehicle simulation, CD Tire models were used to compare the performance of the different Tyre designs for reducing the In-Cabin Noise (ICN). The Tyre design parameters affecting the ICN were identified, and the ICN performance of the improved tyre design was verified by the physical tyre’s in-cabin noise measurements & full vehicle simulation using CD Tire models of the improved tyre. The subjective evaluation of In-Cabin Noise was conducted with the expert drivers, and the ratings correlated with the objective measurements obtained from the simulations and measurements.

Singh, Ram Krishnan, Deivasigamani Purushothaman, Balakrishnan, Paua, Ketan, Ahire, Manoj, Adiga, Ganesh N

Exploring the Influence of Wheel Rim Width on Tyre Performance through Rig-Testing and Vehicle-Level Evaluation: A Comprehensive Study

2026-26-0603

1/16/2026

With increasing demand for improving the vehicle Ride and Handling (R&H) performance, the synergy between vehicle subsystems such as suspension, chassis, brakes & tyres play a major role towards it. In this regard, the interaction between wheel rim width and tyre performance characteristics is a key focus area in vehicle development process. Detailed research is being conducted worldwide to understand their dynamics of interaction and based on the tested data, vehicle manufacturers make the design selection. In this context, the proposed study aims to provide a in-depth analysis of how variations in wheel rim width affect key tyre performance parameters such as lateral force characteristics, damping property, tyre footprint, and pinch cut resistance. Also, the subsequent influence on vehicle-level performance parameters such as R&H, braking, steering, and durability is captured. Based on these analysis, appropriate wheel rim size selection is done which is most optimal for the project requirements. The study involves multiple rig-level testing and full-vehicle evaluation data through which several observations have been tabulated which reinforce the previous studies and provide new insights. Firstly, it was observed that narrower wheel rims tend to have reduced rolling resistance in turn offering higher fuel efficiency. However, this comes at the cost of reduced lateral grip and stability during vehicle direction-changing maneuvers. In contrast, wider wheel rims enhance traction and cornering power by providing a broader contact patch between the tyre and the road surface. Furthermore, the study shows that the tyre sidewall pinch-cut performance is deteriorated with wider wheel width. This is due to the tyre mounted on a narrower rim showing uniform energy dissipation along the cavity thus preventing any sidewall cuts during curb impacts. In conclusion, this study shows a detailed perspective on the intricate relationship between wheel rim width and tyre performance characteristics which can help vehicle OEMs to make quicker and informed decisions regarding wheel rim width selection to optimize both performance and efficiency while ensuring safe driving conditions.

Singh, Ram Krishnan, Paua, Ketan, Sundaramoorthy, Ragasruoban, Lenka, Visweswara, ahire, Manoj, Adiga, Ganesh N

Comprehensive Research Study Examining Tyre Wear and its Indian Perspective

2026-26-0604

1/16/2026

Automobile emissions refer to the gases and particles released into the atmosphere by vehicles during their operation. These emissions contribute to environmental pollution and have an impact on human physiology and environment. This paper assimilates findings from a comprehensive research study examining tyre wear and its Indian perspective. Tyre wear understood as a factor affecting road safety, environmental health, and economic sustainability. The study identifies factors affecting tyre wear and provides overview regarding tyre wear generation in India, encompassing road infrastructure, vehicle characteristics, driving patterns, and environmental factors. Moreover, it examines the adverse effects of these particles on human health, such as respiratory ailments and cardiovascular diseases, as well as their impact on ecosystems. This paper delves measures to measure tyre wear and safeguard both environmental and public health. It also covers the tyre wear measurement methodologies to provide a comparison of methods used for estimating tyre wear. This paper is an attempt to summarize effects of tyre wear and its Indian perspective. Specific market serves specific requirements. Bringing forward India specific perspective of tyre usage patterns, it is common observation that Indian tyre consumption pattern is different than the developed countries like other developed countries. Varied environmental conditions, road conditions and usage patterns also affect tyre wear. This paper will address various such aspects also.

Joshi, Amol, Khairatkar, Vyankatesh, Belavadi Venkataramaiah, Shamsundara

Novel Approach for Predicting Steering Rack Load Using Multi-Body Simulation

2026-26-0378

1/16/2026

In the initial stages of a vehicle development program, the sizing of various components is a critical deliverable. The steering system, in particular, requires a precise estimation of the rack load for the appropriate sizing of the rack and assists units. Accurately predicting the load on the system during the early stages of development is challenging, especially in the absence of benchmark or legacy data. Commonly used processes for estimating parking steering effort often employ simplistic approaches that may fail to account for parameters such as tire size, vertical stiffness, and steering geometry, leading to reduced accuracy. This paper introduces an advanced methodology for predicting steering rack loads, which incorporates considerations such as contact patch size and pressure variation, as well as the tire jacking effect. The methodology involves mathematical modeling of the contact patch using mesh-grids, utilizing common inputs available in the early stages of vehicle development, such as tire size, tire vertical stiffness, front axle weight, and suspension geometry variations. This approach aims to reduce development time while enhancing accuracy. The predicted results have been found to closely align with physical measurements. The findings indicate that the proposed methodology significantly improves the precision of steering rack load predictions, thereby facilitating the design of more resilient and efficient steering systems.

Shirke, Umesh, Dabholkar, Aniruddh, Bardia, Vivek, Srivastava, Harshit, Prasad, Tej Pratap

Driver-in-the-Loop Optimization of Tire-Vehicle Dynamics for Variant Application through Physical Tire Model

2026-26-0099

1/16/2026

Today due to time to market requirements, Original Equipment Manufacturers (OEM) prefers platform modularity for Product Development in Automotive Domain. Money and time being main constraint we need to focus on single platform which can give flavors of different category just by changing Ride height and Tyre and some extra tunable. Taking this as challenge still tyre development for new variant demands lot of time and iterations which can lead to delays in time to market. This study provides a virtual development process using driver in loop Simulator and Multi body dynamics simulation which are real time capable and integrating physical tire models. The proposed alteration introduces ride height changes, weight distribution changes, and center of gravity changes from existing vehicle design. The proposed new vehicle variant also introduces tire change from highway terrain type to all-terrain type as it was intended to deliver some off-roading capabilities, thereby vehicle dynamics and kinematics recalibration & tuning required. The conventional development cycles through physical prototypes are time-consuming and expensive. Alternatively, this solution combines high-fidelity tire simulation, driver-in-the-loop (DIL) simulation, and multi-body dynamics analysis to reduce development time and prototyping. The proposed method begins with baseline & modified vehicle variant comparison, augmenting Adams vehicle models with variant parameters and reference against VI-Grade simulations. Performance gaps are then identified, and a sensitivity analysis identifies critical tire parameters (e.g., cornering stiffness, tread block dynamics) influencing handling characteristics. Virtual tire models with different constructions are then iteratively tested within the simulator for achieving the desired performance. The best tire iterations based on the subjective feel are then considered for ADAMS simulations and the best tire iteration is further selected based on the objective metrics.

Shrivastava, Apoorv, Asthana, Shivam

Drive Cycle Based Energy Audit & Range Estimation for 4X2 Electric Truck

2026-26-0163

1/16/2026

Transportation sector in India accounts for 12% of total energy consumption. Demand of energy consumption is being met by the imported crude oil, which makes transportation sector more vulnerable to fluctuating international crude oil prices. India is mindful of its commitment in 2016 Paris climate agreement to reduce GHG emissions intensity of its GDP by 40% by 2030 as compared to 2005 levels. To fast track the decarbonization of transportation sector, commercial vehicle manufacturers have been exploring other viable options such as battery electric vehicles (BEVs) as a part of their fleet. As on today, BEV has its own challenges such as range anxiety & high total cost of ownership. Range anxiety can be certainly addressed by optimum sizing of electric powertrain, reduction in specific energy consumption (SEC) & use of effective regeneration strategies. Higher SEC can be more effectively addressed by doing vehicle energy audit thereby estimating the energy losses occurring at each powertrain component of an electric vehicle. The work illustrated in this paper involves drive cycle-based energy audit & range estimation for 4X2 rigid electric truck using simulation approach. It involves strenuous exercise of simulation specific input data generation by doing rigorous component level tests for battery, motor, tires & auxiliaries. Duty cycle data was acquired for 3000 km & condensed cycle of 32 minutes was formed which represents real world usage pattern. Data recorded in component and vehicle tests was used to build robust simulation model in GT-DRIVE. Simulated SEC was validated within 4% with on road trails. 73.5% of battery discharge energy was used to overcome rolling resistance loss, aerodynamic drag loss, electromechanical conversion loss, auxiliary losses, braking losses & differential losses. Effective power at wheels observed to be 26.5% of total battery discharge energy. Sensitivity analysis for RAR, RRC, coasting & braking regeneration limits was carried out and effect of each parameter on final SEC was studied and optimum set of parameter combination was suggested to the OEM. Outcome of this project has also laid down the sophisticated methodology to carry out energy audit of any electric vehicle, which in turn will help to bring simulation predictions much closer to the real-world scenarios.

Gijare, Sumant, Karthick, K., Juttu, Simhachalam, Thipse, Sukrut S., A, Jothikumar, J, Frederick Royston, SR, Subasree, G, Harini, M, Senthil Kumar

Development of a GUI-Based Pitch Sequence Optimization Tool for Tire Noise Reduction

2026-26-0330

1/16/2026

Tire noise reduction is important for improving ride comfort, especially in electric vehicle due to lack of engine noise and majority of the noise generated in-cabin is from tire-road interaction. Therefore, the tire tread pattern contribution is one of the important criteria for NVH performance apart from other structurally generated noise and vibration. In this work a GUI-based pitch sequence optimization tool is developed to support tire design engineers in generating acoustically optimized tread sequences. The tool operates in two modes: without constraints, where the pitch sequence is optimized freely to reduce tonal noise levels; and with constraints, where specific design rules are applied to preserve pattern consistency and manufacturability. The key point to be considered in this pitch sequence is that it should be reducing the tonal sound and equally spread i.e., the same pitch cannot be concentrated on one side which may lead to non-uniformity. So, the restriction is that the highest and lowest pitch types cannot occur adjacent to one another. This design rule helps in reducing undesirable pattern non-uniformity and improves both acoustic and structural performance. This tool helps in faster design iteration and integration with downstream development processes. This tool is also validated in current OE projects showing promising improvements in tire noise behavior while maintaining realistic design feasibility.

Sampathraghavan, Lakshmi, Ramarathnam, Krishna Kumar, Mantripragada PhD, Krishna Teja, Ramachandran, Neeraj

Experimental Evaluation of Tyre Vertical Dynamic Stiffness and Damping for Ride Model Applications Using Flat Trac

2026-26-0607

1/16/2026

The vertical dynamic stiffness and damping of a tyre are critical to ride comfort and overall dynamics, particularly for low-frequency excitations in urban and highway driving. As the tyres are the primary interface between the vehicle and the road, absorbing surface irregularities before the suspension engagement, precise tyre parametrization is essential for accurate ride models. This study investigates an experimental methodology characterizing the vertical dynamic behavior of pneumatic tyres using a Flat Trac test machine. Contrary to the conventional approaches that depend on intricate shaker rigs or frequency dependence function models, the proposed technique uses a realistic force displacement loop-based methodology which is appropriate for ride models. Dynamic stiffness is computed from slope of a linear regression fitted to force and displacements during vertical sinusoidal excitation. Damping is derived from hysteresis energy loss per cycle. The tests were conducted under various conditions by varying vertical loads, inflation pressures (IP), excitation frequencies, and deflection amplitudes (4–8 mm). The generated stiffness and damping curves from the test results can be directly applied in quarter-car models and could potentially be extended to the full-vehicle ride simulations for ride characteristics assessment studies. Research indicates that the dynamic stiffness of a non-rolling tyre is consistently higher than that of a rolling tyre. Under rolling conditions, dynamic stiffness increases with test speed due to excitation frequency effects. Additionally, vertical dynamic stiffness correlates positively with inflation pressure (IP); increasing it from 216 to 264 kPa yields a 12–14% rise in stiffness for both rolling and non-rolling condition. The proposed framework facilitates the integration of realistic tyre vertical dynamics into vehicle ride models while maintaining minimal complexity, thereby improving simulation fidelity and supporting better design and evaluation of ride quality in early stage of vehicle development.

Duryodhana, Dasari, Sethumadhavan, Arjun, Tomer, Avinash, Ghosh, Prasenjit, Mukhopadhyay, Rabindra

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