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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7QnJha2UgY29tcG9uZW50cyZxdW90OyIgb3JpZ2luYWxfdmFsdWU9IiZxdW90O0JyYWtlIGNvbXBvbmVudHMmcXVvdDsiIC8+PC9maWx0ZXJzPjxyYW5nZXMgLz48c29ydHM+PHNvcnQgZmllbGQ9InB1Ymxpc2hlZCIgb3JkZXI9ImRlc2MiIC8+PC9zb3J0cz48cGVyc2lzdHM+PHBlcnNpc3QgbmFtZT0icmFuZ2V0eXBlIiB2YWx1ZT0icHVibGlzaGVkZGF0ZSIgLz48L3BlcnNpc3RzPjwvc2VhcmNoPg==" rel="self" type="application/rss+xml" />
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    <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>
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    <item>
      <title>Real-time and online industrial system for detecting defects of interface surface in automobile brake pipe</title>
      <link>https://trid.trb.org/View/2691730</link>
      <description><![CDATA[A defect detection algorithm based on dual-level cascade and multi-feature scale fusion Faster Region based Convolutional Neural Network (Faster-RCNN) is proposed to overcome the challenges of uneven distribution, small size, and diverse morphology of interface surface defects on the automotive brake pipe. Basing on Faster-RCNN, the proposal of multi-scale feature fusion combines feature information from different scales together to ensure that easily overlooked small targets can be noticed. Region of Interest (RoI) alignment pooling is proposed to reduce the deviation between the original feature regions and the mapped feature regions. To reduce the impact of uneven sample distribution on algorithm performance, a two-stage cascade structure is constructed to enable that different samples use different Intersection over Union (IoU) thresholds. The design of the loss function was optimized to balance the learning ability of the algorithm between easy and difficult samples. A “Defect” dataset is constructed and it validates the effectiveness of the improved algorithm. The improved algorithm achieves Precision (P) of 90.3%, Recall (R) of 84.5%, and mean Average Precision (mAP) of 91.1%. It has been demonstrated that the improved Faster-RCNN defect detection algorithm exhibits high accuracy and robustness. According to the production requirements of the actual industrial production, an integrated online defect detection system has been established, which combines testing for rotation integrity, groove completeness, and interface surface defects. The experimental results indicate that the system achieves an accuracy of 99.4%, a false positive rate of 1.2%, a false negative rate of 0.5%, and a detection time of 0.78 s. The integrated online defect detection system reduces the reliance on manual inspection, enhancing production efficiency and ensuring consistent quality, thereby meeting stringent production standards.]]></description>
      <pubDate>Thu, 23 Apr 2026 13:54:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691730</guid>
    </item>
    <item>
      <title>Structural Redesign and Functional Integration of an Electrohydraulic Brake Valve for Enhanced Performance and Manufacturability</title>
      <link>https://trid.trb.org/View/2669752</link>
      <description><![CDATA[The Electrohydraulic Brake Valve (EBV) is a vital component in full-power brake systems for heavy-duty and off-highway vehicles, providing precise hydraulic pressure modulation through electrical control. Traditionally, EBV housings are manufactured using bar-machined components, which offer durability but contribute significantly to the overall weight and cost of the assembly. In response to increasing demands for lightweight and cost-effective solutions, this study presents a targeted design optimization of the EBV housing.The redesigned housing adopts a casting-based geometry, integrates sensor ports for pressure monitoring, and includes a nameplate mounting provision for customer identification. Material substitution and structural simplification were employed to enhance manufacturability and performance. Finite Element Analysis (FEA) was used to validate the mechanical integrity of the new design under operational conditions. The optimized EBV assembly achieved a weight reduction of approximately 60% and a cost reduction of nearly 25%, demonstrating the effectiveness of design-led innovation in improving manufacturability.]]></description>
      <pubDate>Tue, 31 Mar 2026 16:34:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669752</guid>
    </item>
    <item>
      <title>Validation of a virtual model of a contact thermocouple with real measurements</title>
      <link>https://trid.trb.org/View/2665928</link>
      <description><![CDATA[In this article, a detailed study is presented on the influence of clamping force when measuring the surface temperature of a brake disc using thermocouples. The focus in this research is on modifying the computational model of thermocouples and subsequently analyzing them using the finite element method (FEM) to assess the accuracy of temperature measurement under different force conditions. A comprehensive validation process was conducted through experimental measurements of the stiffness of the slider arm, ensuring the reliability of the FEM models. The study revealed that achieving agreement with experimental results required a correction factor for the stiffness of the contact element. The findings of this research will contribute to improving methodologies for evaluating brake disc temperatures, thereby enhancing the accuracy of temperature measurements in brake system testing for railway vehicles.]]></description>
      <pubDate>Mon, 23 Mar 2026 15:15:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2665928</guid>
    </item>
    <item>
      <title>Electronic Regulation of Thermoelectric Modules in a Flow Cooler</title>
      <link>https://trid.trb.org/View/2665917</link>
      <description><![CDATA[The study addresses the design and implementation of two potential solutions for cooling water in the brake stand of railway vehicles, focusing on accuracy, efficiency, and compliance with technical standards. A detailed exploration is provided of an electronic cooling system that utilizes modern microprocessors for precise regulation of the output water temperature. The goal is to achieve the required temperature parameters as specified by UIC 541-3 and IRS 50548, which details the exact conditions for testing train braking systems. The proposed system integrates Peltier modules (thermoelectric devices) for temperature regulation, enabling water cooling. Multiple temperature sensors are incorporated to ensure accurate feedback for the control unit. Two primary variants of the cooling system control are presented. The first variant uses relay circuits for control, offering a straightforward solution. The second, alternative solution, employs transistor-based control through drivers, which enhances regulation dynamics and system efficiency. The scientific contribution of this study is the analysis and design of various solution variants that meet the water temperature requirements as per UIC 541-3 and IRS 50548 standards. The results can be applied not only in the testing of braking systems but also in other fields where temperature regulation is crucial. By integrating advanced control strategies, such as TEC-based cooling for braking components, braking stands can improve the precision of thermal management during tests, leading to more accurate and repeatable results. The synergy between electronic cooling systems and braking test stands presents a promising direction for future research, supporting the ongoing transition to greener and more efficient railway transport solutions.]]></description>
      <pubDate>Mon, 23 Mar 2026 15:15:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2665917</guid>
    </item>
    <item>
      <title>Development of brake chamber failure prediction model using machine learning</title>
      <link>https://trid.trb.org/View/2646094</link>
      <description><![CDATA[Brake chambers used in transport trucks are the most important parts in terms of safety. However, they are prone to deterioration due to internal corrosion caused by rust, which makes visual inspection difficult. Therefore, by using machine learning to learn about the operating conditions of trucks, we aim to develop a predictive model that estimates the risk of brake chamber failure and use it as a criterion for deciding whether to perform expensive disassembly and inspection.]]></description>
      <pubDate>Fri, 20 Mar 2026 14:47:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2646094</guid>
    </item>
    <item>
      <title>Benchmark of Conventional and By-Wire Brake System Layouts for
     Electric Vehicle Applications by Numerical Simulations</title>
      <link>https://trid.trb.org/View/2669773</link>
      <description><![CDATA[The recently increasing global concern about sustainability and greenhouse gas                     emission reduction has boosted the diffusion of electric vehicles. Research on                     this topic mainly focuses on either re-designing or adapting most conventional                     vehicle subsystems, especially the propulsion motor and the braking                     components.In this context, the present work aims to model, analyze, and compare                     three-braking system layouts design alternatives focusing on their contribution                     to vehicle performance and efficiency: a commercial vacuum-boosted hydraulic                     braking system, a commercial integrated electrohydraulic braking system, and a                     concept distributed electrohydraulic brake system. Braking systems performance                     are evaluated by simulating key maneuvers adopting a full model of a battery                     electric vehicle (BEV), which includes all relevant components like tires, and                     powertrain dynamics, which is validated against real-world data. Implementation                     and integration of the first two systems are discussed, followed by the design                     and detailed modeling of the third, which includes a control strategy for                     pressure modulation, including antilock braking system (ABS) and electronic                     stability control (ESC) functionalities. Once the simulation environment is set,                     simulations are performed and KPIs are defined to compare the three braking                     systems from both the performance and the energy consumption point of view. The                     results show that the distributed electrohydraulic system reduces the time to                     lock by 30.8%, the stopping distance by 5.89%, and the energy consumption by                     more than 50% in specific test cases compared to the analyzed vacuum-boosted                     system due to its distributed hardware and control architecture and                     power-on-demand operation.]]></description>
      <pubDate>Tue, 17 Feb 2026 10:29:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669773</guid>
    </item>
    <item>
      <title>Further Investigation of Variables Affecting Brake Squeal: Porosity Effect on Lowmet Pad Properties</title>
      <link>https://trid.trb.org/View/2600521</link>
      <description><![CDATA[As Lowmet pad porosity increases, pad hardness decreases; pad ISO compressibility increases; the nominal friction coefficient increases (SAE J2522); and the disc wear/pad wear decreases. Brake squeal occurrence is affected by the total wear of disc and pads; the wear differential between the inboard pad and outboard pad; pad tangential taper; and pad hardness/material damping. Also, pad chamfer shape has a strong influence on brake squeal occurrence.]]></description>
      <pubDate>Fri, 24 Oct 2025 11:55:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2600521</guid>
    </item>
    <item>
      <title>Brake Drag Optimization: A Perspective on Virtual and Physical Tools for Developing Near-Zero Drag Sliding Calipers</title>
      <link>https://trid.trb.org/View/2604426</link>
      <description><![CDATA[The ever-increasing prevalence of electric vehicles (EVs) in the global market continues to push automakers towards more stringent brake drag requirements. As OEMs seek to differentiate themselves with greater vehicle range to offset consumer anxiety as a barrier for entry to EVs, brake caliper suppliers see requirements for zero or near-zero drag at the component level becoming commonplace. Despite this pressure, many practical concerns exist with torque measurement capabilities in the sub 1.0 N-m range. Additionally, the authors have observed an industry tendency to employ suboptimal engineering methodology for assessing drag concerns, with trial and error attempts continuing to perplex engineers more than it provides solutions. This paper will seek to reintroduce to the reader the basic physics of brake drag from a fundamental free body diagram level, review statistical approaches for characterizing the individual forces acting within the caliper, and propose a simple – yet effective – virtual tool for characterizing potential solutions. The virtual tool will be correlated with physical assessments, and the practical challenges of full brake corner drag evaluations will be discussed. Finally, recommendations will be presented for evolving sliding caliper design to enable zero drag.]]></description>
      <pubDate>Mon, 13 Oct 2025 16:31:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2604426</guid>
    </item>
    <item>
      <title>Evaluation and Prevention of Brake Drum Freezing by Aerodynamic Measures</title>
      <link>https://trid.trb.org/View/2539707</link>
      <description><![CDATA[The use of drum brakes in Battery Electric Vehicles (BEVs) offers numerous benefits, including energy efficiency, reduced brake dust emissions, and reliable performance under challenging weather conditions. The capability of regenerative braking reduces the friction brake application frequency in BEVs and therefore the brakes can be prone to corrosion and performance degradation especially considering conventional disc brake systems. The closed design of a drum brake prevents corrosion of the friction-components by sealing out water, dirt or snow. A common sealing concept is performed with a labyrinth between the gap of the rotating drum and the axle mounted backplate. A hermetical isolation of water and snow ingress into the drum cannot be achieved with this concept, so additional aerodynamic measures are necessary to deflect the air/water path and protect the inner brake components. Additionally, interfaces like wheel cylinders, electric park brake parts, brake shoe pins, and axle mountings can potentially lead to leaks on the backplate. This study highlights the impact of water/snow ingress on the example of a frozen parking brake during cold climate on-road testing. Through scientific investigation using the state-of-the-art fluorescence method, drum leakages were visualized, and the extent of water ingress was measured. Multiple multiphase CFD simulations supported the design phase of the aerodynamic measures. Subsequently, the vehicle was cooled down to -10 °C to simulate the cold climate test conditions. The frozen parking brake situation could be reproduced with this method, and beneficial aerodynamic and sealing measures were extrapolated to avoid the drum brake from freezing. The tests were conducted in the FKFS Thermal Wind Tunnel, a wind tunnel comprising a two-axle-dynamometer and water irrigation systems with UV illumination.]]></description>
      <pubDate>Tue, 15 Apr 2025 13:56:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2539707</guid>
    </item>
    <item>
      <title>Application of Topology Optimization and Artificial Intelligence based Evolutionary Algorithm to Minimize the Contribution of the Caliper in Brake Squeal Noise</title>
      <link>https://trid.trb.org/View/2431255</link>
      <description><![CDATA[The squeal noise is one of the critical factors to qualify a disc brake design from the Noise Vibration and Harshness (NVH) perspective. It is imperative to be watchful of the unstable natural modes of the brake assembly which trigger squeal. Any design modification for reducing a part’s contribution to targeted squeal mode can adversely affect and give rise to new squeal modes. Also, controlling conflicting requirements like mass, strength, and casting manufacturability, further adds up complexity, which increases design iterations and product cost. In view of these challenges, the application of the topological optimizations embedded under an artificial intelligence (AI) driven optimization workflow is explored. The scope of optimization is kept limited only to the caliper. Complex eigenvalue (EV) finite element analysis (FEA) of baseline design brake assembly is performed which predicts critical squeal mode having 34% strain energy contribution from caliper. To improve the squeal performance, surface morphing-based shape optimization with mode tracking is explored, which can be useful in the finetuning stages of the design. However, at the initial stages, topological optimizations play an important role in obtaining suitable concepts. Since commercial topological optimization tools do not support complex EV analysis, an integrated and automated workflow is developed. In this, the caliper geometry is first topologically optimized for mass, stiffness, casting manufacturing constraints, followed by complex EV analysis of the optimized geometry. A dummy thermal analysis is included in topology optimization, which equivalently simulates irrotational inviscid fluid flow to improve casting filling performance. Furthermore, a computational fluid dynamics (CFD) solver is added to the workflow to simulate the viscous flow effects during filling process. AI based evolutionary multi-objective optimization algorithm is used to perform multi-disciplinary optimization on the caliper geometry. The best candidate obtained from virtual design iterations exhibited significant reduction in caliper’s strain energy contribution to 9% or less in squeal all modes, reduction in number of squeal modes while having better strength as compared to baseline design with controlled weight addition.]]></description>
      <pubDate>Tue, 17 Sep 2024 13:43:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2431255</guid>
    </item>
    <item>
      <title>Piston and Guide-Pin Rattle Noise Mitigation in Electro-Mechanical Brake Caliper</title>
      <link>https://trid.trb.org/View/2431229</link>
      <description><![CDATA[Brake caliper commonly utilizes rubber or spring components to maintain specific clearance range for sliding characteristics, rendering them susceptible to rattle noise. The Electro-Mechanical Brake (EMB) caliper has attracted attention for its advantageous features such as reduced brake drag, optimized vehicle layout, and precise brake control. However, the inclusion of additional components related to the dry-type pressurizing system results in increased caliper weight and susceptibility to rattle noise. This study thoroughly examines rattle noise characteristics in our prototype EMB caliper, identifying primary noise sources on the piston and guide-pin sides. Implementing piston seals and guide-pin boots tightening force proves the effectiveness in improving rattle noise characteristics. Collisions between the piston and ball-screw head can be mitigated by piston inner seal, significantly reducing rattle noise. The effectiveness of the piston outer seal is limited and can be sufficiently substituted through improved tightening force in the piston boot. Additionally, the guide-pin side is identified as significant source of rattle noise, with enhancements in guide-pin boot tightening force showing improved rattle noise characteristics, particularly under new pad conditions. These findings provide valuable insights for developing EMB calipers to minimize rattle noise, contributing to quieter and more efficient future braking systems.]]></description>
      <pubDate>Tue, 17 Sep 2024 13:43:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2431229</guid>
    </item>
    <item>
      <title>Analysis of Disc-Brake Squeal Considering Lining Wear</title>
      <link>https://trid.trb.org/View/2431251</link>
      <description><![CDATA[Brake squeal is a phenomenon caused by various factors such as stiffness of brake components, mode coupling, friction coefficient, friction force variation, pressure, temperature and humidity. FEA simulation is effective at predicting and investigating the cause of brake squeal, and is widely used. However, in many FEA simulations, models of brake lining are mostly a brand-new shaper, so that the change of pressure distribution or pad shape, which can occur due to the lining wear, are not taken account. In this research, brake squeal analysis was conducted with consideration of lining wear, applying Fortran codes for Abaqus user subroutine. The brake assembly model for the analysis is created by using a 3D scanner and has a close shape to the real one. The wear patterns calculated by the analysis are similar to those of brake pads after a noise test. The complex eigenvalue analysis shows two unstable modes at the frequency of squeal occurred in the noise test. One is out-of-plane vibration mode of the rotor and another is in-plane vibration mode of the rotor. These modes do not come out in the case of analysis with a brand-new lining shape. The results of parameter studies on physical properties and geometries of brake lining show the analysis model in this research is effective in reducing squeal of the brake system.]]></description>
      <pubDate>Mon, 16 Sep 2024 16:19:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2431251</guid>
    </item>
    <item>
      <title>Application of Neural Networks for Real-Time Decision Support in Virtual Approval of Brake Components</title>
      <link>https://trid.trb.org/View/2419736</link>
      <description><![CDATA[This study aims to present a virtual numerical validation procedure for durability in brake system components, using artificial neural networks and based on experimental bench tests. The study focus was concentrated on the drum brake spider component, responsible for mechanically connecting the brake system subassemblies. To develop the validation procedure, engineering software such as ABAQUS, Fe-Safe, Minitab, and MATLAB was used. These were crucial for carrying out stress analyses, statistical data validation, and construction of an Artificial Neural Network (ANN) capable of predicting finite element responses, fatigue life, and supporting real-time decision-making for structural validation of mechanical components. The results obtained from these tools allowed the calibration of a numerical virtual model using the Finite Element Method (FEM) based on mechanical theories and results obtained in bench tests with the brake system, thus, a finite element database was generated for the application of the ANN, containing 130 data from a total of 4,800 possible combinations. The training, validation, and testing of the ANN were determined using a performance analysis algorithm. Finally, the results obtained with the artificial neural network were compared with the results of finite elements and computational fatigue life. The efficiency of the real-time response prediction method was measured using the Mean Squared Error (MSE). With the use of ANN, it was possible to obtain an average error of 0.85% for predicting maximum principal stress and an error of 10.33% for predicting fatigue life. For the classification of fatigue life results, the ANN presented an accuracy of 100%, enabling decision-making in real-time.]]></description>
      <pubDate>Wed, 21 Aug 2024 14:09:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2419736</guid>
    </item>
    <item>
      <title>Design of Torque Density Improved Spoke-Type IPMSM for Electric Brake Booster Take Into Account Axial Leakage Flux</title>
      <link>https://trid.trb.org/View/2394949</link>
      <description><![CDATA[In order to analyze spoke-type interior permanent magnet synchronous motors (IPMSMs) accurately, it is necessary to apply 3-D finite element analysis (3-D FEA) that takes into account axial leakage flux. However, 3-D FEA is disadvantageous due to the significant inputs of time and effort required. Therefore, it is necessary to use 2-D finite element analysis (2-D FEA) to produce reliable analysis. Precise analysis of IPMSMs using 2-D FEA should consider the leakage magnetic flux generated at the axial end of the rotor core. The magnetic loss caused by leakage flux along the axial direction can be considered in 2-D-FEA by estimating the axial leakage flux path of the rotor due to the potential difference between poles and poles and correcting the permeability of the permanent magnets (PMs). The proposed 2-D FEA was applied to analyze a spoke-type IPMSM with overhanging and cross-laminated rotor structures. Finally, the reliability of the proposed analysis method was verified by comparing the results of the proposed model with 3-D FEA results and experimental results.]]></description>
      <pubDate>Wed, 14 Aug 2024 11:01:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2394949</guid>
    </item>
    <item>
      <title>Additive brakes</title>
      <link>https://trid.trb.org/View/2319430</link>
      <description><![CDATA[The aim of this article is to approach the problem of additive brakes, their description, comparison and requirements placed on this type of brakes. The author wrote this thesis because of his interest in road vehicles - their individual systems, specifically the additive brakes of trucks and buses. The result is a detailed description and analysis of individual types of additive brakes.]]></description>
      <pubDate>Thu, 18 Apr 2024 17:07:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2319430</guid>
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