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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=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" rel="self" type="application/rss+xml" />
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    <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>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Robust and optimised sub-component detection using 3D point cloud for shipbuilding sub-assembly automation</title>
      <link>https://trid.trb.org/View/2693638</link>
      <description><![CDATA[This study proposes a 3D object detection system to reliably detect components in complex environments using 3D point cloud data to automate arrangement operations in shipbuilding sub-assembly processes. To achieve this, an improved RANSAC algorithm was developed by integrating a scoring scheme that considers normal vector similarity, inlier distribution, and the presence of regions containing the topmost feature points. Following the initial model estimation, a refitting procedure based on the inlier set was performed to enhance the stability and accuracy of the plane model. Additionally, a priority-based sampling method was applied to the plane estimation process to optimise computational efficiency. A component-selection algorithm was developed that considered the classification ID, position, size, count, and remaining status of the recognised components, and a fully integrated processing framework was constructed to transmit the recognition results in real time for direct use by a gantry robot. Applying the proposed system to a shipyard sub-assembly environment demonstrated stable recognition performance under stacking conditions, with average dimensional and pose errors of 2.4 mm and 0.35°, respectively. The average processing time was 0.99 s, confirming the suitability of the system for real-time automated processes.]]></description>
      <pubDate>Tue, 21 Apr 2026 14:31:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2693638</guid>
    </item>
    <item>
      <title>Variation Management in Design for Aircraft Assembly</title>
      <link>https://trid.trb.org/View/1787701</link>
      <description><![CDATA[In order to be more competitive, aerospace industries have to continually improve product's cost, quality and cycle time. One way to perform all three at once is to manage product's variations, as variations are responsible for waste, rework and delay. There are only three ways to reduce product's variation: improve manufacturing capability, improve assembly capabilities and manage assembly sequence. Generally, variation reduction programs tackle only manufacturing capabilities. Unfortunately this solution is by far the most expensive one. We propose in this article to reduce variation first by selecting best assembly sequences or eliminating assembly tools and only after if there is no other way by reducing manufacturing capabilities. With this aim, we have defined an assembly analysis method. This method studies for each assembly sequence how variations are flowed from part to part through the assembly joints. Two types of assembly joint have been defined: mates that pass positional variation from part to part and contact that merely provide support and block variations. To represent variation flow down, we propose to use an “Assembly-Oriented Graph” and a “Datum Flow Chain”. First one captures the assembly sequence and allows us to identify which joints are mates and which ones are contacts. The second represents where variations are driven in the product. Datum Flow Chains assess assembly families and best ones are selected. This method can be used from the preliminary design allowing validating assembly sequence and design principles without serious investment. This method has been applied with success at Aerospatiale-Matra on various aircraft assemblies.]]></description>
      <pubDate>Mon, 29 Dec 2025 09:37:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787701</guid>
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    <item>
      <title>Understanding Quality in the IPT</title>
      <link>https://trid.trb.org/View/1787697</link>
      <description><![CDATA[Quality has been the illustrious word of the 80s and 90s as we speak organizations are chasing quality problems through the engineering teams and into production. Taskforces of workers in white coats are being sent on to the production line to furiously check components, monitoring process capability in an attempt to improve product quality. Unfortunately it's only after several years of production that the first “real” data gets back to the engineering teams, when it is often too late to remove the causes of these quality problems. The organization is left kicking itself over the same old catch twenty-two situations, “If only the team knew this process data before they decided to engineer it like that!” The challenge set to the integrated product teams (IPT) is “How does the IPT effectively develop its knowledge of the portfolio of manufacturing processes available for a particular program in time to impact product design in order that a quality product is developed at an affordable cost?” This paper provides an overview and examples of a practical approach to developing this knowledge within the IPT. It covers the following topics: The identification and capture of product requirements with relationship to assembly and part features in the early phases of Integrated Product Development (IPD). The application of geometric dimensioning and tolerancing (GD&T) to these features and its impact on location, manufacturing and inspection methodologies. The development of “up front” generic process parts to initiate the flow of process capability data. The interpretation of this information within the IPT to support product development.]]></description>
      <pubDate>Mon, 29 Dec 2025 09:37:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787697</guid>
    </item>
    <item>
      <title>Design for Tooling to Enable Jigless Assembly - An Integrated Methodology for Jigless Assembly</title>
      <link>https://trid.trb.org/View/1787714</link>
      <description><![CDATA[Jigless assembly is an approach towards reducing the cost and increasing the flexibility of tooling systems for aircraft manufacture through the minimisation of product-specific jigs, fixtures and tooling. A new, integrated methodology has been developed, which uses a number of building blocks and tools, to enable design for jigless assembly as a result of a logical, step-by-step process. This methodology, AIM-FOR-JAM, is currently being applied to redesign the Airbus A320 Fixed Leading Edge for jigless assembly, as part of the ‘Jigless Aerospace Manufacture’ (JAM) project.]]></description>
      <pubDate>Mon, 22 Dec 2025 13:19:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/1787714</guid>
    </item>
    <item>
      <title>Wing movement path planning method during wing-fuselage docking process based on measured data and improved PSO-RRT* algorithm</title>
      <link>https://trid.trb.org/View/2569603</link>
      <description><![CDATA[Wing-fuselage docking is one of the most crucial stages in the aircraft assembly process. In China, the process of wing-fuselage docking for large aircraft relies on experience and on-the-spot error detection during the docking process currently. However, the inefficiency of the approach makes it difficult to meet the demands of efficient production. Moreover, aircraft wings are susceptible to deformation, and various manufacturing errors can lead to different types of deformations. To address this problem, an inverse planning method for wing docking paths was developed, leveraging measured data and an enhanced PSO-RRT* algorithm. Firstly, a part model was reconstructed using measured point cloud data to depict manufacturing errors accurately. Then, the deformation occurring during the wing positioning process was simulated based on this model. Finally, improved PSO-RRT* algorithm was proposed and the inverse planning of wing docking path was executed. The experiment showed that the average absolute error between wing deformation simulation and measured values is 0.0015 mm. The maximum absolute error is 0.03182 mm. Finally, to ensure that the generated path can be used for the actual assembly process. A path smoothing method based on cubic spline interpolation was proposed, and the path was segmented.]]></description>
      <pubDate>Wed, 13 Aug 2025 09:25:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2569603</guid>
    </item>
    <item>
      <title>Solid Block Approach for Hole-Cutting Procedure in Overset Assembling</title>
      <link>https://trid.trb.org/View/1974249</link>
      <description><![CDATA[Hole-cutting procedure is a process identifying cells which are inside a body (“in-wall” cell) defined by other overlapped grids in overset assembling, and one of the crucial process to exclude “in-wall” cells from flow computation. Solid block approach is an approach which uses several grids (solid block) to define the interior region of the body and identify “in-wall” cells which are inside the solid blocks. Solid block approach can eliminate the use of special treatment for the case in which enclosed surface mesh is not available such as open-ended surface or decomposed surface meshes. The approach using solid block which covers a body inside can make hole-cutting procedure simple and straightforward. There is not a limit for a number of grids in the approach, then it has the capability to carry overset assembling for more complicated geometry.]]></description>
      <pubDate>Mon, 20 May 2024 14:02:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974249</guid>
    </item>
    <item>
      <title>Shake table testing of out-of-plane response of repaired bridge subassembly with simplified ABC-inspired cast-in-place joints</title>
      <link>https://trid.trb.org/View/2146618</link>
      <description><![CDATA[Accelerated bridge construction (ABC) has been utilized in precast bridge structures because of its advantage to expedite on-site construction. In ABC, one of the main concerns is the joint connection as it needs to be well designed to maintain structural integrity. A recent study at the University of Nevada, Reno (UNR) was conducted to utilize ABC pocket connection concept in cast-in-place (CIP) cap beam-column bridge joint. The cap beam was constructed by having the cap beam longitudinal reinforcement bundled outside the pocket joint allowing the placement of the column reinforcement cage uninhibited. The specimen was tested in an inverted position at one of UNR’s shake tables and found to perform well under out-of-plane ground motion excitations, and the ductility of the column was confirmed through typical plastic hinge behavior. In this study, the specimen from the recent UNR test was further utilized by removing the damaged column in the cap beam through cutting and coring. A new column was constructed in the cap beam using the same reinforcement detailing from the original specimen. The repaired specimen was tested using the same loading protocol adopted from the 1994 Northridge earthquake as the original model. The objective of this study is to demonstrate that ABC-inspired CIP joints can provide a viable repair method after major earthquakes, where damaged columns can be replaced without affecting cap beam reinforcement. The repaired specimen performed well as the plastic hinge zone was developed in the column outside the joint, close to the interface of the cap beam, as desired and required by design. The cap beam remained essentially elastic, i.e. capacity-protected as required, throughout the test which is similar to the performance of the original model. High residual drift ratios were recorded at higher earthquake motions and were attributed to the slippage of the column in the joint. The paper also concludes with recommendations for the repair of CIP cap beam-column joints emulating ABC pocket connections.]]></description>
      <pubDate>Tue, 23 May 2023 10:08:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2146618</guid>
    </item>
    <item>
      <title>An Accurate Point Set Matching Method for Hull Blocks With Engineering Constraints</title>
      <link>https://trid.trb.org/View/2122591</link>
      <description><![CDATA[To effectively improve the precision matching technique of measurement point set and design point set for hull blocks, an accurate point set matching method for hull blocks with engineering constraints (verticality, levelness, symmetry, flatness, etc.) and elimination error points is presented. It is divided into initial matching and refine matching. In initial matching, the improved Random Sample Consensus algorithm is proposed to eliminate error points rapidly and accurately; the improved Coherent Point Drift algorithm is proposed to obtain more accurate initial matching. In refine matching, the Analytic Hierarchy Process is used to obtain each weight of engineering constraints automatically, and the weight vector is introduced into the multi-optimization objective function to achieve the more reasonable matching results. The results proved that this method can rapidly and automatically eliminate error points, and get more accurate and reasonable results meeting engineering constraints. It can provide the basis for the subsequent assembly of hull blocks.]]></description>
      <pubDate>Wed, 29 Mar 2023 09:27:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2122591</guid>
    </item>
    <item>
      <title>Product development and process capability - case of quality tools application</title>
      <link>https://trid.trb.org/View/1814605</link>
      <description><![CDATA[All dimensional variation of assembly in structures is based on the geometry stack up between for profiles and localization of pins or holes in fixtures. The capability for a smaller dimensional variation is proportional to the number of stack up and the components geometry of the assemblies. When a product objective is defined, the structure of parts of intermediate sub assemblies compose the basis for the study, therefore the construction and stack up of tolerances of each part or process can be better based on combinations that are defined by the tool of robust engineering. As much bigger is the geometric dependence in the stack up, greater will be the variation probability. One understands for geometric dependence is the detailed dimensional consequences for the geometry of contact between components.]]></description>
      <pubDate>Fri, 30 Sep 2022 12:03:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1814605</guid>
    </item>
    <item>
      <title>Novel method of estimation of inertial and dissipative parameters of a railway pantograph model</title>
      <link>https://trid.trb.org/View/1988721</link>
      <description><![CDATA[An increase in electric railway vehicles service velocity requires that correct interaction between the pantograph and the catenary is ensured. This implies the need for developing mathematical models of pantographs and catenaries and determining their parameters. The article presents a method to determine parameters of mechanical joints of a railway pantograph based on analysis of pantograph subassemblies in swinging motion. The experimental tests consisted in disassembling the pantograph and creating partial subassemblies which were then analysed with respect to their damped linear or angular oscillations. The simulation analysis required developing, in CAD, 3D models of individual pantograph parts and their subassemblies. Defined were joints between particular elements, which represent of real pantograph structure. The inertia parameters of the model were determined, based on structural characteristics and physical properties of materials, used for manufacturing individual pantograph elements, and then verified experimentally. The dissipative parameters of the mechanical joints were calculated iteratively. The model of complete pantograph assembly was also subject to verification and in this case, good convergence between simulation and experiment results was achieved. The obtained parameter values can be used in simulation models of other railway pantographs having a similar structure.]]></description>
      <pubDate>Wed, 24 Aug 2022 15:05:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/1988721</guid>
    </item>
    <item>
      <title>Advanced FRF Based Determination of Structural Inertia Properties</title>
      <link>https://trid.trb.org/View/1812314</link>
      <description><![CDATA[Accurate estimation of inertia properties is crucial in the design and development cycle of mechanical structures. When modeling complex structures and subassemblies, or simulating the dynamics of mechanisms, the rigid body characteristics of a subassembly might be too complex or inaccurate to calculate. Traditionally, inertia properties are obtained by a laborious pendulum test, a very time consuming procedure. A highly accurate alternative is to perform a typical modal test, inertia properties are than achieved based on frequency response function and its mass line characteristic. This paper explains, first of all, how to extract inertia properties such as center of gravity, moments and principal axes of inertia based on frequency response functions (FRF's), and then how to synthesize rigid body characteristics such as rigid body modes with respect to the geometry and the resulted inertia properties. Both an academic case and real-life applications are used to validate the approach. Moreover, different aspects such as measurement setup, influence of number of responses and references on the accuracy are also discussed in this paper.]]></description>
      <pubDate>Wed, 23 Feb 2022 16:16:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1812314</guid>
    </item>
    <item>
      <title>Axle Imbalance Measurement and Balancing Strategies</title>
      <link>https://trid.trb.org/View/1812131</link>
      <description><![CDATA[This paper summarizes a study on axle balance measurement and balancing strategies. Seven types of axles were investigated. Test samples were randomly selected from products. Two significant development questions were set out to be answered:]]></description>
      <pubDate>Wed, 23 Feb 2022 16:16:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/1812131</guid>
    </item>
    <item>
      <title>Performance Optimization of Compressor Rotor Clutch Sub-assembly Using Electro-?Magnetic Analysis</title>
      <link>https://trid.trb.org/View/1560889</link>
      <description><![CDATA[Rotor Clutch sub-assembly is one of the very important sub-assemblies (S/A) of an automotive compressor as it delivers the required torque/power to run the compressor. It mainly consists of rotor and bearing, stator, hub and armature. Rotor is rotated by engine pulley through belt drive system, while stator housing has got number of coils winded around stator slot. The hub sub-assembly is attached to the compressor shaft via spline arrangement and bolted across. When direct current (DC) is supplied to the terminal of the rotor, an electromagnetic field is generated which causes to attract the hub part towards rotor. Once the hub and rotor gets engaged each other, torque is transmitted to the compressor shaft which then helps to complete the suction and compression of refrigerant gas and thus making the vapor cycle run to produce adequate cooling in the air-conditioning (AC) system. Hence it is most important to ensure adequate and even distribution of electromagnetic field which is solely responsible for providing torque to the compressor.         The present paper describes the numerical simulation of electromagnetic field of a clutch sub-assembly of an automotive compressor. ANSYS software was used to simulate the same. 2dimensional geometry of clutch rotor sub-assembly was created from computer aided design (CAD) tool and imported in suitable format. Meshing was performed using shell elements and the necessary material properties like permeability and B-H curve were defined along with the load conditions. The obtained flux density was then optimized by changing the shape and size of clutch sub-assembly. Further to this shaft torque was calculated analytically using the numerically obtained flux density and validated with the required torque for compression/suction process. The validation results exhibit a good trend and correlation, thus helping to develop a procedure to design clutch sub-assembly ‘first time right’ at the design stage. It is also ensured by this to have adequate torque delivered to the compressor.       ]]></description>
      <pubDate>Tue, 03 Dec 2019 14:01:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560889</guid>
    </item>
    <item>
      <title>Automotive Production Control, Using Thermal Vision Systems – A Passive Thermal Imagery for Process Control</title>
      <link>https://trid.trb.org/View/1429627</link>
      <description><![CDATA[This work presents new generation of online inspection systems, developed and deployed in automotive assembly plants, to provide 100%, online evaluation of automotive processes and subassemblies. The presented systems are thermal-vision based, with capability to provide two dimensional, spatial and temporal temperature acquisitions, and are equipped with novel processing routines for data collection, conditioning and processing. Specific systems are presented in the stamping presses, paint curing practices, with inspection schemes designed to provide an efficient manufacturing sequence, through (1) pro-active diagnosis routines to monitor the process performance, while inspecting the product, (2) focusing on the error detection rather than defect detection routines, and (3) utilizing closed loop, feedback communications. This work will also present the processing computations that combine known image processing tools with inverse conduction computations, to correlate the process, product health parameters, to acquired scans temperature readings. Presented work will include two implementations of proposed thermographic systems; the automated detection of splits for body in white BIW sub-assemblies in automotive stamping presses, in addition to stamping die temperature control. Second example is a thermal vision system implemented, to evaluate the protective coating coverage and its curing uniformity for automotive, steel fuel tanks.       ]]></description>
      <pubDate>Mon, 30 Oct 2017 11:05:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/1429627</guid>
    </item>
    <item>
      <title>Cyclic Tests of Precast Pretensioned Rocking Bridge-Column Subassemblies</title>
      <link>https://trid.trb.org/View/1467685</link>
      <description><![CDATA[Rocking columns reinforced with unbonded prestressing offer advantages for bridges constructed in seismic regions because they can recenter the structure after an earthquake. Under lateral load, the columns rock on the foundation and cap beam, and rotate as rigid bodies rather than deforming. This paper describes cyclic load tests of two subassemblies representing parts of a bridge bent constructed using precast pretensioned rocking columns, spread footings, and a precast cap beam. The subassemblies, representing two halves of a single column, were subjected to cyclic lateral displacements of increasing amplitude under a constant vertical load. The proposed column design has several advantages over conventional cast-in-place construction. The use of precast columns and cap beams reduces on-site construction time. The use of unbonded prestressing minimizes residual displacements after an earthquake. The strands are deliberately debonded through the clear height of the column and bonded to the column concrete at the top and bottom, where the column is embedded in the cap beam and footing, respectively. The columns are confined by steel tubes and annular end plates at their interfaces with the footings and cap beams to minimize concrete damage when the columns rock. In the tests, the columns returned to their initial location with essentially no concrete damage after being displaced to peak drift ratios exceeding 10%. At the end of the tests, the columns’ lateral strengths still exceeded 80% of their peak values. The tests also provided the opportunity to evaluate practical procedures for proportioning key details of the system.]]></description>
      <pubDate>Tue, 30 May 2017 08:23:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1467685</guid>
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