<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Research on Parameter Optimization of Hydro-Pneumatic Suspension System for Mining Dump Trucks Based on Genetic Algorithm</title>
      <link>https://trid.trb.org/View/2777848</link>
      <description><![CDATA[To improve Vehicle ride and handling characteristics. comfort of mining dump trucks under adverse road conditions, this paper conducts parameter optimization research on its key component—the hydro-pneumatic suspension system. Firstly, the suspension parameters are sampled using the Latin Hypercube method, and a vehicle dynamics model is constructed using MATLAB/Simulink to obtain the vehicle body vertical acceleration response under different working conditions. On this basis, a high-precision surrogate model between the suspension design parameters and the vehicle body vertical acceleration RMS, a key ride comfort metric is established based on the Kriging model. Furthermore, with the objective function of minimizing the RMS value of the vehicle body vertical acceleration, and considering the constraints of tire dynamic load and suspension dynamic deflection, a parameter optimization model for the hydro-pneumatic suspension system is established. The genetic algorithm is employed to solve this model, achieving the global optimization of the initial gas pressure and initial gas volume in the front accumulator and rear suspensions, and the damping orifice diameter. The research results show that after optimization by the genetic algorithm, the RMS value of vertical dynamics of the vehicle body acceleration is significantly reduced under both no-load and full-load states, when driving on Grade D and Grade E roads at different speeds. The maximum optimization improvement rate reaches 67.3%, effectively proving the effectiveness and practicality of the proposed optimization method in enhancing vehicle ride performance. This provides multiple sets of optimal passive parameters forming a lookup table for the subsequent design of active control strategies.]]></description>
      <pubDate>Wed, 16 Sep 2026 09:15:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2777848</guid>
    </item>
    <item>
      <title>A Robustness Approach to Reducing Variability in Suspension System Performance</title>
      <link>https://trid.trb.org/View/2772516</link>
      <description><![CDATA[Determination of part tolerances for reduced variation in suspension level performance by using Multi-objective Robust Design Optimization (MORDO)The car industry is very competitive, and companies need to satisfy their customers to keep or grow their market share. It’s important for car makers to build affordable cars that provide a good driving experience, comfort for passengers, and safety for everyone. Suspension systems are very important for how a vehicle rides, handles, and stays stable, and they directly affect how driving feels. If parts are not positioned correctly, it can really impact how well a vehicle works. As a result, suggested limits for where suspension parts are placed are given to prevent issues with Kinematics and Compliance (K&C) properties. So, designing parts with the right tolerances is very important in making vehicles. It helps lower production costs and keeps the vehicle's performance consistent. This paper shows a step-by-step method to find the strongest solution that meets all the requirements for suspension performance. Multi-objective Robust Design Optimization (MORDO) and Reverse Multi-objective Robust Design Optimization (R-MORDO) have been used to find strong solutions while keeping K&C parameters intact. K&C analysis is done with ADAMS/CAR software, and Multi-Objective Robust Design optimization is done using Mode Frontier.]]></description>
      <pubDate>Mon, 31 Aug 2026 15:22:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/2772516</guid>
    </item>
    <item>
      <title>Advanced Damping Force Modeling Using Machine Learning for
          Next-Generation Electric Vehicle Suspensions</title>
      <link>https://trid.trb.org/View/2761643</link>
      <description><![CDATA[The rapid evolution of electric vehicles (EVs) has led to the development of                     innovative approaches to optimize ride comfort, handling, and the overall                     suspension performance. EVs introduce unique challenges due to their distinct                     weight distribution, powertrain dynamics, and noise characteristics, unlike                     their conventional internal combustion engine (ICE) counterparts. This paper                     outlines an advanced damping force modeling methodology using machine learning                     (ML) techniques to enhance the suspension design process for next-generation                     EVs. The analysis is based on data-driven ML algorithms, i.e., Gradient                     Boosting, Random Forest, and Neural Networks, to simulate the nonlinear and                     frequency-dependent phenomenon of dampers in different operating conditions. A                     comprehensive dataset, generated through simulation and experimental testing,                     captures the effects of road profiles, vehicle dynamics, and damping settings.                     Additionally, this research evaluates the impact of machine-learned damping                     force predictions on critical ride and handling metrics, including ride comfort,                     road-holding ability, and energy efficiency. The results demonstrate that the ML                     models can enhance the iterative design process considerably and help to create                     the adaptive suspension systems that will address the particular requirements of                     EVs. This paper contributes to advancing the state-of-the-art of the suspension                     modeling, incorporating the ML-based insights in the development cycle. It                     highlights the possibility of artificial intelligence to transform suspension                     design, paving the way for superior ride quality and vehicle performance in                     electric mobility.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:49:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761643</guid>
    </item>
    <item>
      <title>Analysis of the Impact on Ride Comfort from Splitting the Unsprung
          Mass in Vehicle Modeling</title>
      <link>https://trid.trb.org/View/2761638</link>
      <description><![CDATA[The study was conducted to investigate the differences in ride comfort analysis                     between treating the unsprung mass as a whole and modeling it separately. A                     classical two-degrees-of-freedom single-wheel vehicle vibration model and a                     three-degrees-of-freedom single-wheel vehicle vibration model with split                     unsprung mass were established, with their state-space descriptions determined.                     The fundamental vibration response quantities of both models were identified,                     and time-domain simulations under random road excitation were performed using                     MATLAB/Simulink. The results indicate that the two modeling approaches exhibit                     minimal differences in ride comfort analysis for the sprung mass, but there are                     certain differences for the unsprung mass. Additionally, for the                     three-degrees-of-freedom single-wheel vehicle vibration model with split                     unsprung mass, the axle-to-wheel mass ratio was introduced to analyze the                     changes in the fundamental vibration response quantities when the unsprung mass                     increases by a fixed value and is distributed differently between the axle and                     the wheel. The results show that variations in the axle-to-wheel mass ratio have                     no significant impact on the vibration characteristics of the sprung mass.                     Reducing the mass ratio, i.e., transferring part of the unsprung mass to the                     wheel, can somewhat reduce the vertical acceleration of the unsprung mass, but                     it will slightly increase the relative dynamic load on the wheel. Finally, the                     other two models were simplified by combining the two masses connected by the                     bearings.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:49:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761638</guid>
    </item>
    <item>
      <title>Electromagnetically Levitated Engine Mount</title>
      <link>https://trid.trb.org/View/2761925</link>
      <description><![CDATA[In the evolving landscape of the automotive industry, enhancing passenger comfort and ride quality has become a key differentiator for manufacturers. While suspension systems have traditionally received significant attention, powertrain isolation through engine mounts plays an equally critical role in controlling noise, vibration, and harshness (NVH). Engine mounts are not only responsible for supporting the powertrain’s weight but also for mitigating the transmission of unbalanced engine forces to the vehicle body. Modern engine mount designs aim to eliminate any metal-to-metal contact between the powertrain and chassis, thereby achieving optimal vibration isolation. This study proposes a refined approach to completely decouple the powertrain from the vehicle structure, ensuring minimal vibration transfer and thereby extending the operational life and performance of the engine mount system.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761925</guid>
    </item>
    <item>
      <title>Refinement of Road Induced Steering Wheel Vibration in Electric Vehicle</title>
      <link>https://trid.trb.org/View/2761848</link>
      <description><![CDATA[Nowadays, customers expect excellent cabin insulation and superior ride comfort in electric vehicles. OEMs focus on fine tuning the suspension system in electric vehicle to isolate the road induced shocks which finally offers superior ride quality. This paper focuses on enhancing the ride comfort by reducing the road excitation which originates mainly due to road inputs. Higher steering wheel vibration is perceived on the test vehicle on rough road surfaces. To determine the predominant force transfer path, Multi reference Transfer Path Analysis (MTPA) is performed on the front and rear suspension. Based on the finding from MTPA, various recommendations are explored and the effect of each modification is discussed. Apart from this, Operational Deflection Shape (ODS) analysis is used to determine the deflection shape on the entire steering system . Based on ODS findings, recommendations like dynamic stiffness improvements on the steering column and steering wheel are explored and the impact on the steering wheel vibration is discussed. With all the counter measures proposed, steering wheel vibration levels are reduced by ~ 7 dB . Component level modal targets are proposed to avoid the vibration concern due to road excitation.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761848</guid>
    </item>
    <item>
      <title>Adaptive Control Algorithms for Active Mounts on Diesel Powertrains in Passenger Cars</title>
      <link>https://trid.trb.org/View/2761844</link>
      <description><![CDATA[Diesel powertrains are inherently characterized by high vibration levels and low-frequency excitations, which are extremely demanding for passenger comfort and vehicle refinement. Conventional passive engine mounts often fall short in mitigating such vibrations effectively across a wide range of operating conditions. Passive mounts are inadequate for effectively isolating vibrations in powerful, lightweight vehicles or those without a balancer shaft 3-cylinder engine ordiesel engines. Consequently, this has prompted the consideration of active engine mounts as an alternative solution for solving NVH (Noise, Vibration, Harshness)-related issues. This paper explores the application of adaptive control algorithms in active engine mount systems for diesel powertrains in passenger vehicles. Through the integration of real-time feedback loops with smart control strategies the system adaptively controls mount stiffness and damping to minimize engine-induced vibrations. The study presents simulation and experimental results showing enhanced vibration isolation, better ride quality, and lower transmitted forces to the vehicle chassis. In addition, the adaptive control ensures high robustness under varying driving conditions, such as load variations and engine transients. This trend opens up the future for next-generation diesel vehicle NVH solutions with a comfort-performance-fuel efficiency balance.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761844</guid>
    </item>
    <item>
      <title>Predictive Simulation Framework for Tyre Curb Impact Durability Assessment and Design Optimization</title>
      <link>https://trid.trb.org/View/2761819</link>
      <description><![CDATA[With increased deterioration of road conditions worldwide, automotive OEMs face significant challenges in ensuring the durability of structural components. The tyre being the primary point of contact with the road is expected to endure harshest of impacts while maintaining the other performance functions such as Ride & Handling, Rolling resistance, Braking. Thus, it is considered as the most challenging component in terms of design optimization for durability.The current development method relies on physical testing of initial samples, followed by iterative construction changes to meet durability requirements, often giving trade-off in Ride & Handling performance. To overcome these challenges, a frugal simulation-based methodology has been developed for predicting tyre curb impact durability before vehicle-level testing so that corrective action can be taken during the design stage.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761819</guid>
    </item>
    <item>
      <title>Determining Optimal Suspension &amp; Body in White Mountings to maximize Off-Road Capability of Passenger Vehicles</title>
      <link>https://trid.trb.org/View/2761781</link>
      <description><![CDATA[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.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761781</guid>
    </item>
    <item>
      <title>Modelling and Simulation of Key Vehicle Dynamics Parameters for a Conceptual Race Car</title>
      <link>https://trid.trb.org/View/2761754</link>
      <description><![CDATA[Vehicle dynamics is a vital area of automotive engineering that focuses on analyzing how a vehicle responds to driver inputs and external factors like road conditions and environmental influences. Achieving optimal performance, safety, and ride comfort requires a detailed understanding of longitudinal, lateral, and vertical dynamic behavior. The objective of this paper is to develop and validate the model of a concept Race car and evaluate its vehicle dynamics behavior using IPG CarMaker, a high-fidelity virtual testing environment widely used in industry. The model incorporates a range of vehicle parameters, including suspension parameters like spring and damper characteristics, mass distribution, tire properties and powertrain parameters. The performance evaluation is done as per standard guidelines, including Constant Radius turn test, Sine Steer test and other standard tests like Acceleration, Braking along with Ride and Comfort classification. The key parameters that are calculated and validated are vehicle accelerations in the principal axes, stopping distance, yaw velocity and yaw velocity gain, vehicle roll characteristics, steering parameters, ride and driver comfort metrics. Validation of simulation outputs is achieved through comparison with empirical data obtained from literature and mathematical calculations based on vehicle dynamics principles. The test results show a close correlation between mathematical and simulated values, therefore accurately predicting vehicle behavior.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761754</guid>
    </item>
    <item>
      <title>Comfort Study of Air Suspension System Based on MPC Control</title>
      <link>https://trid.trb.org/View/2742523</link>
      <description><![CDATA[Air springs are increasingly replacing traditional shock absorbers in vehicle suspension systems due to their superior mechanical properties, including adjustable stiffness, nonlinear characteristics, and excellent damping performance. To further explore the potential of air suspension in improving ride comfort, this paper focuses on air suspension. We first conducted mechanical characteristic experiments on air springs to obtain their stiffness and damping characteristics under different inflation pressures and excitation frequencies. These tests provide essential mechanical parameters for subsequent modeling and simulation. Based on the experimental data, a simplified 1/4 air suspension simulation model is constructed, taking into account the nonlinear stiffness and damping properties of the air springs. To simulate real-world driving conditions, a random road surface model is introduced as the excitation input. Simulation analysis is conducted to compare the air suspension system with the traditional passive suspension system. The results indicate that, compared to the passive suspension system, the air suspension system integrated with Model Predictive Control(MPC) significantly reduces key performance indicators, including suspension deflection, wheel dynamic load, and sprung mass vertical acceleration. This indicates that the suspension with model predictive control can effectively suppress vehicle vibrations, thereby enhancing ride comfort and driving stability. The results of this study provide an important basis for the optimal design of air suspension systems and have practical application value for improving the suspension performance of the vehicle.]]></description>
      <pubDate>Mon, 03 Aug 2026 15:36:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2742523</guid>
    </item>
    <item>
      <title>Methodological Framework for the Derivation of Objective Criteria for Ride Comfort Assessment</title>
      <link>https://trid.trb.org/View/2724745</link>
      <description><![CDATA[In recent years, the automotive industry has faced increasing pressure to accelerate development cycles and reduce costs. Simultaneously, ride comfort standards have risen due to the ongoing integration of autonomous driving functionalities. Consequently, it has become essential to ensure that ride comfort attains a high degree of maturity at the very early stages of the automotive development process. This necessitates the establishment of objective criteria that enable the reliable estimation of subjective ride comfort, utilizing simulation-based assessment methods.This study introduces a methodological framework designed to systematically translate the manufacturer specific subjective perception and assessment of ride comfort into objective descriptions using a dynamic driving simulator. The framework is conceived as a generic approach, enabling the comprehensive application to a wide spectrum of subjective ride comfort phenomena, while being specifically optimized for the challenges of the automotive industry. Employing this framework facilitates the derivation of highly detailed, objective descriptions of subjective ride comfort evaluations, which promotes the achievement of advanced ride comfort maturity for new vehicles in early development phases and supports the overall enhancement of ride comfort.The exemplary application of the framework to a transient, one-dimensional ride comfort phenomenon demonstrates its capability to derive robust objective models from subjective evaluations conducted with professional test drivers in a dynamic driving simulator environment.]]></description>
      <pubDate>Tue, 21 Jul 2026 11:41:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2724745</guid>
    </item>
    <item>
      <title>Analysis and Improvement of Rattle Noise in Manual Transmission</title>
      <link>https://trid.trb.org/View/2732239</link>
      <description><![CDATA[In response to the problem of manual transmission rattle noise in the acceleration process of a truck, the mechanism of the problem is analysed, and the scheme is developed and verified from two aspects: reducing the torsional vibration of the system and reducing the response of the transmission gear. The results show that, on the one hand, reducing the clutch stiffness and optimizing the torsional vibration of the system can reduce the rattle noise of the transmission; On the other hand, it can also reduce the rattle noise of transmission gears by improving the engagement precision of transmission gears and reducing the gear clearance. Considering the improvement effect, cost, and influence on other performance of the two schemes, the appropriate engineering scheme is selected to effectively solve the problem and improve the riding comfort of the product.]]></description>
      <pubDate>Tue, 21 Jul 2026 11:36:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2732239</guid>
    </item>
    <item>
      <title>Research on the Influence of Suspension Characteristics on Ride Quality of Railway Wagon</title>
      <link>https://trid.trb.org/View/2732219</link>
      <description><![CDATA[With the country’s economy and people’s consumption capacity increasing, railroad transportation tasks have become more and more frequent, and it is growing the demand for the transportation of high-value goods, fresh produce, etc. Compared with traditional Freight vehicles, express freight vehicles have great advantages in terms of carrying capacity, mobility, and transportation cost, but when it run at a speed of 160 km/h, it often occurs that failure of axle-box rubber springs, primary vertical dampers, secondary lateral dampers, anti-yaw dampers, and air springs. How to ensure the safety and stability of the train under suspension system failure conditions is a problem that needs to be solved during the design process. In this paper, through multi-body system dynamics software, a nonlinear dynamics model of lateral and vertical coupling of the vehicle system is established to analyze the influence of suspension system failure on the stability of 160 km/h express freight vehicles. The analysis results show lowering the operating speeds can meet the Ride Quality of the Vehicles in special conditions.]]></description>
      <pubDate>Tue, 21 Jul 2026 11:36:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2732219</guid>
    </item>
    <item>
      <title>Development of a GUI-Based Pitch Sequence Optimization Tool for Tire Noise Reduction</title>
      <link>https://trid.trb.org/View/2712090</link>
      <description><![CDATA[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.]]></description>
      <pubDate>Wed, 10 Jun 2026 17:05:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2712090</guid>
    </item>
  </channel>
</rss>