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Combining light metals like aluminum to produce lightweight structures offers a high weight‐saving and contributes to a circular economy in automotive car body construction. Compound casting is a promising process for producing car body parts. Difficulties arise in creating metallic continuity between insert and casting. Insert coatings are used to remove the oxide layer and thereby improve the wettability of the melt. This study uses a hybrid joining method to improve the metallic bond between insert and casting. Induction heating differently influences the strength properties of age‐ and nonage‐hardenable inserts. Compression shear tests characterize the metallic bond strength. Microscopic images show the influence of the process variables on the compound quality. Reproducible sound metallic bonding with low scattering is achieved by enhancing the compound casting process through induction and no insert coating. Cast wall thicknesses down to 4 mm contribute to further lightweight potential as they have the same strength level as the reference sample. A decisive factor is the insert temperature in the compound zone. Thereby, insert preheating conditions play a crucial role. Additional heat treatment of hardenable compounds leads to a further increase in metallic bond strength. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modifying the car body structure from the existing train to another car body type requires an analysis of several factors. The strength of the design due to overload and the durability of the structures due to operational loads need to be re-evaluated. Furthermore, stiffness analysis also needs to determine the characteristics of the structure when it is not loaded. This study numerically analyzed the considerations in selecting the structural steel profile for modification of the existing car body into a panoramic type using the ANSYS Workbench R19. The underframe structure can still be used, and other structures are modified with the UNP profile. The side wall, and roof are changed in shape and size following the glass design of the panoramic train. The solid 3D model is rebuilt into a surface model to simplify the analysis. Static structural analysis is used to clarify the strength of the design under overload, a combination of static and transient structural analysis is applied to calculate the operating life, and modal analysis is chosen to figure out the stiffness. The simulation results showed that the modified design had met the needs and requirements based on the PM 175 standard of 2015 by the Indonesian Ministry of Transportation and the international standard EN-12663.

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The dynamic performance of a high-speed train is heavily influenced by its centre of gravity and moment of inertia. Therefore, accurately measuring these parameters is crucial. This paper proposes an integrated test method for measuring the centre of gravity and moment of inertia based on the excitation method by analyzing the structural characteristics of the vibration test bench. The proposed method is efficient as it only requires installing the car body once, unlike the past method of combining excitation and suspension. This paper provides a comprehensive theoretical derivation of the method used to test the center of gravity and moment of inertia of a specific type of high-speed electrical motor units (EMU) car body. The results of the test were compared to the theoretical values, and the error was found to be minimal, meeting the necessary engineering application requirements. [ABSTRACT FROM AUTHOR]

The evaluation of the vibration behavior of railway vehicle car bodies based on the results of numerical simulations requires the adoption of an appropriate theoretical model of the suspension which considers the important factors that influence the vibration level of the car body. In this paper, the influence of the secondary suspension model on the vertical vibration behavior of the railway vehicle car body is investigated, based on the results of numerical simulations on the frequency response functions of the acceleration, the power spectral density of the acceleration and the root mean square of the acceleration of the car body. Numerical simulation applications are developed based on a rigid-flexible coupled vehicle model with seven degrees of freedom, corresponding to car body vibration modes: bounce, pitch, and first vertical bending mode, and bogie vibration modes: bounce and pitch. Four different models of secondary suspension are integrated into the vehicle model, namely a reference model and four analysis models. Analysis models include systems through which the pitch vibration of the bogies is transmitted to the car body, influencing its vibration behavior and, respectively, a system that takes the relative angular displacement between the car body and the bogie and a system that models the transmission system of the longitudinal forces between the bogie and the car body are analyzed. The effects of these two systems on the vibration behavior of the railway vehicle car body are analyzed both for each system separately and together. In the conclusions of the paper, the influence of the secondary suspension model on the vibration level at the resonance frequencies of the vertical bending of the car body and the pitch of the bogie is pointed out. It also highlights the important contribution of the transmission system of the longitudinal forces between the bogie and the car body in transmitting pitch vibrations of the bogies to the car body, with effects on the vibration level of the car body at high speeds.

Spot welded joints play a crucial role in the construction of modern automobiles, serving as a vital method for enhancing the structural integrity, strength, and durability of the vehicle body. Taking into account spot welding process in automotive bodies, numerous defects can arise, such as insufficient weld nugget diameter. It may have evident influence on vehicle operation or even contribute to accidents on the road. Hence, there is a need for non-invasive methods that allow to assess the quality of the spot welds without compromising their structural integrity and characteristics. Thus, this study describes a novel method for assessing spot welded joints using ultrasound technology. The usage of ultrasonic surface waves is the main component of the proposed advancement. The study employed ultrasonic transducers operating at a frequency of 10 MHz and a specially designed setup for testing various spot welded samples. The parameters of the spot welding procedure and the size of the weld nugget caused differences in the ultrasonic surface waveforms that were recorded during experiments. One of the indicators of weld quality was the amplitude of the ultrasonic pulse. For low quality spot welds, the amplitude amounted to around 25% of the maximum value when using single-sided transducers. Conversely, for high-quality welds an amplitude of 90% was achieved. Depending on the size of the weld nugget, a larger or smaller amount of wave energy is transferred, which results in a smaller or larger amplitude of the ultrasonic pulse. Comparable results were obtained when employing transducers on both sides of the tested joint, as an amplitude ranging from 13% for inferior welds to 97% for superior ones was observed. This research confirmed the feasibility of employing surface waves to assess the diameter of the weld nugget accurately. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper analyses the dynamic behavior of a rail vehicle using experimental and simulation analysis on a multi-rigid–flex body model. The mathematical models are developed considering the car body, bogie frame, and wheel axle for rail vehicles of rigid–flexible and multi-rigid formulations, taking the car body as rigid for the rigid body analysis and the flexible car body for flex–rigid analysis. A finite element model of the car body was developed in ANSYS, and substructure and modal analyses were performed. The mathematical model is validated through an experiment conducted by the Research Design and Standards Organization. Then, the validated model is further analyzed to evaluate the running comfort, using the Sperling ride index and the running safety, by investigating the derailment coefficient and wheel load reduction rate. The impact of flexibility on the vehicle's running stability is investigated using the rigid body dynamics model and experimental data. Compared to experimental data, the simulation results reveal that elastic vibration cannot be neglected in vehicle dynamics, since the rigid–flexible coupling model is slightly more significant than the rigid-body model for ride comfort and safety. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A reliability‐based design optimization (RBDO) method of a car body is presented on basis of dimension‐reduced Chebyshev polynomial method (DCM). To improve calculation efficiency and save computational time, complex models are often approximated by metamodels in reliability analysis. Traditional metamodels require a large number of sample points, which is time‐consuming. To improve the efficiency, DCM is proposed to approximate the performance function of the car body. First, the performance function is decomposed by the dimension‐reduction method into a sum of univariate functions, which are then fitted through Chebyshev polynomials. The reliability of the car body is predicted by the Taylor expansion method and the fourth‐moment method. Finally, the result of RBDO is obtained using an improved adaptive genetic algorithm. The proposed method saves on the calculation time with high precision. Besides, the improved adaptive genetic algorithm reduces the number of iterations in the car body optimization and improves the efficiency. [ABSTRACT FROM AUTHOR]

Serious corrosion was found on 6005A aluminium alloy edge beam on one side of traction converter hung on the car body of a train during maintenance. In order to determine the corrosion reason, the failure analysis of the side beam was carried out by means of macro and micro morphology observation, EDS analysis, metallographic structure inspection, chemical composition analysis, combined with the actual operation status on site. Results showed that there was intergranular corrosion on the 6005A aluminium alloy edge beam. The cracks occurred in the surface and propagated to the interior along the grain boundaries. Because the side beam was in the corrosive environment near the sewage outlet, the intergranular corrosion cracks occurred on the surface of the local area of the edge beam and the substrate on the local surface of material fell off, resulting in the corrosion failure of the edge beam.

One of the developments in automotive technology is identified by the increasing variety of vehicle products in the market. This development also leads to the refinement of the design of a more aerodynamic car shape to reduce air friction which can reduce material consumption. Because in theory, the aerodynamic shape of the vehicle's body can reduce fuel consumption and minimize the forces that hinder the vehicle's speed. The purpose of this study is to design a more aerodynamic car body, determine the air flow pattern around the car, and simulating the design of the car body to determine the amount of drag coefficient, using Spoiler and without spoiler E-Falco Car Body with variations in speed of 10 km/h, 20 km/h and 40 km/h. The results of this study indicate that the greater the driving speed, the greater the drag generated. The average drag coefficient for the 3 speed variations is 1,995 for design I and 1,905 for design II. The smallest drag coefficient with a value of 1.887 occurs in Design II with a speed used of 40 km/hour and the largest value of the coefficient of drag with a value of 2.043 occurs in Design I with a used speed of 10 km/hour. Design model II is more aerodynamic than design I, the smallest drag coefficient is 1.887. So that the body for the KMLI 2020 competition is recommended to use the design model II which use Spoiler.

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Field measurements of the elastic vibration of a car body (CB) and its coupling with the underframe equipment vibration were carried out for a high-speed railway vehicle, it was found that there was a significant increase of CB elastic vibration when passing a particular location and the equipment absorbed little of the CB vertical elastic vibration. In order to reduce the CB elastic vibration, the suspension parameters of the underframe equipment in the roll direction were optimized. A simplified vehicle model including the roll motion of the CB and the underframe equipment was built for theoretical study, in which the modal displacement of the CB floor corresponding to the CB diamond mode was extracted from finite-element analysis. Based on the frequency response analysis, the frequency range in which the elastic vibration was magnified was obtained. By increasing the roll moment of inertia of the equipment and decreasing lateral distance between the suspension points, the roll frequency of the underframe equipment was decreased and the CB vibration was reduced. To verify the analysis, a three-dimensional multi-body dynamic railway vehicle system was established in SIMPACK. The optimized parameters were validated and shown to be effective for absorbing the CB diamond-mode elastic vibration. [ABSTRACT FROM AUTHOR]

This paper analyses the dynamic behavior of a rail vehicle using experimental and simulation analysis on a multi-rigid–flex body model. The mathematical models are developed considering the car body, bogie frame, and wheel axle for rail vehicles of rigid–flexible and multi-rigid formulations, taking the car body as rigid for the rigid body analysis and the flexible car body for flex–rigid analysis. A finite element model of the car body was developed in ANSYS, and substructure and modal analyses were performed. The mathematical model is validated through an experiment conducted by the Research Design and Standards Organization. Then, the validated model is further analyzed to evaluate the running comfort, using the Sperling ride index and the running safety, by investigating the derailment coefficient and wheel load reduction rate. The impact of flexibility on the vehicle’s running stability is investigated using the rigid body dynamics model and experimental data. Compared to experimental data, the simulation results reveal that elastic vibration cannot be neglected in vehicle dynamics, since the rigid–flexible coupling model is slightly more significant than the rigid-body model for ride comfort and safety.

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Satisfying the needs of the population in the delivery of perishable freight of good quality largely depends on the stable operation of specialized vehicles and the accuracy of calculating the deadline for transporting freight to the consumer. The main value used to calculate the deadline for the transportation of perishable freight by rail is the heat transfer coefficient of the body of an insulated car or container. The accuracy of estimating this value is especially important when using isothermal cars or containers that are not equipped with cooling or heating systems as specialized vehicles. In this paper authors assess the influence of some external factors on the value of the heat transfer coefficient of the body of an isothermal vehicle. The change in the heat transfer coefficient due to the influence of the speed of the isothermal vehicle and insolation is taken into account. The heat transfer coefficients from the internal and external building envelopes to the ambient air for the standing car and during its movement are determined to assess the change in the heat transfer coefficient from the criterion dependencies. Taking into account real external factors, in particular outdoor temperature, humidity, train speed, significantly affects the heat transfer coefficient of the body of an isothermal vehicle, the value was determined in stationary conditions of the workshop and underlying the calculation of the maximum permissible terms for the transportation of perishable freights. This value is excellent from the actual value. As a result of the calculations, a discrepancy of the value of the deadline for the transportation of perishable freights in comparison with the current method is 3–10 %.Changes to the existing methodology will reduce the risk of delivery of perishable freight of inadequate quality due to incorrectly calculated deadlines for transportation.

The article examines methodical issues of selection of heat insulation materials, their properties affecting energy efficiency, as well as methodical issues of experimental determination of heat insulation properties of the car body. This issue has become recently relevant due to the increased requirements to saving of the fuel and energy resources and to improvement of the passenger travel comfort. Domestic and international regulatory documents are analyzed from this perspective.Contemporary materials used for heat insulation of the car body, methods of determination of the average heat transfer coefficient and requirements to such materials are examined. Review of the test results of the most widely spread passenger cars; the issue is arisen regarding necessity of putting the obtained results of experimental research in compliance with the actual operating conditions with regard to the changes of temperature, air humidity and car movement speed.The article examines in details disadvantages of the currently used standardized method of determination of the average heat transfer coefficient. The issues affecting accuracy of determination of this parameter are underlined, which occur in the experimental research and in processing of the obtained results. Practical use of obtained results for designing of new rolling stock is examined.Ultimately, the authors conclude that the valid domestic standardized method of determination of the average heat transfer coefficient does not take into account the number of important conditions. Examination of effect of these conditions on the results of experimental research allows the authors to make conclusion regarding necessity of review of methodical and regulatory and technical documentation for the test methods.

In the past, the magnetorheological (MR) suspension for railway vehicle has obtained great attention for the isolation of vibrations. This work presents a numerical approach to analyse skyhook and ground hook semi-active control methods for railway vehicle suspension. A 10 DoF model of the railway vehicle system is formulated for the comparative analysis between conventional passive and semi-active suspension control in the present study. The non-linear analysis is investigated in time and frequency domain for the sinusoidal excitations from the track. [ABSTRACT FROM AUTHOR]

A novel multi-color painting process was introduced, which does not change the original process route and does not need to return to the main line or build another specialized multi-color painting line. It is basically free from the limit of the output proportion of the multi-color painting car, and features low investment, low energy consumption, high flexibility of production capacity. [ABSTRACT FROM AUTHOR]

Some measures for cost reduction and efficiency improvement in multi-color car body painting process were described. The process flow, the effect of car body shape on shielding, and the future development trend in this field such as EcoPaintJet technology were discussed. [ABSTRACT FROM AUTHOR]

Characteristic defects of paint and varnish coating (LCP) of car bodies, manufactured according to modern painting technologies, are corrosion damage to the metal roof panel. Defects in the form of corrosion of the roof panel are concentrated on the edge in the place of the regular junction of the windshield. Over time, on the painted surface of the bend of the roof panel at the junction of the windshield there are areas with a breakaway paint material to the metal. LCP above the area of corrosion lesions of the metal has swelling, indicating the spread of sub-film corrosion. A number of defects are accompanied by thread-like, visually similar to the web, swelling of the coating, which should be attributed to thread-like corrosion. The purpose of this study is to analyze the causes of destruction of LCP and the development of measures that prevent the development of corrosion foci, will significantly reduce the costs of manufacturers and car owners for warranty repair and operation. With increasing temperature, the rate of corrosion, as well as many chemical processes, increases, as the rate of diffusion, solubility of corrosion products and other processes increase. In order to study the distribution of heat energy from the standard climate system with a heated internal combustion engine, the mode of directing the air flow to the windshield at maximum performance was selected and measurements of thermal fields were made with the help of a thermal imager. During operation, the temperature of the steel body element (roof panel) is one of the determining factors of the appearance of the studied defects. The development of corrosion in this situation depends on the level of movement of heat flows produced by the climate system, and the thermodynamic resistance of accumulated external deposits in the niche (gap) between the windshield and the edge of the roof panel. Removal of deposits is carried out during washing operations. It is proposed to calculate the frequency of washing operations to prevent the development of corrosion. This study also has practical application in conducting technical examinations by manufacturers and independent organizations.

A generalized railway vehicle model is built to study the coupled vibrations between a flexible car body (CB) and the equipment suspended beneath it by taking the complex suspension characteristics of the equipment into consideration. Associated theories for the determination of the suspension parameters for CB suspended equipment are summarized systematically, including the vibration isolation methods and the dynamic vibration absorber (DVA) theories for both undamped and damped cases. The equipment is then grouped into four categories by weight, location, and the excitation that it is subjected to. A general principle for the determination of the suspension parameters is proposed for better vibration isolation effects concerning bogie hunting, the elastic modes of the CB and its excitations. Analysis based on DVA theory shows that 1) siting equipment heavier than 2 t near the CB center can reduce the structural vibrations of the CB considerably, 2) siting medium-weight equipment near one end of the CB is good for absorbing the vibrations resulting from bogie hunting, and 3) a rigid connection is suggested for light equipment. Furthermore, on-track field tests of a high speed train confirmed that the heavy equipment vibrated violently upon absorbing some of the CB vibration energy resulting from bogie hunting. However, solid proof of the vertical bending of the CB was not obtained yet because it was sufficiently damped and is not the first natural mode of a modern aluminum-alloy CB. Further research on the lateral flexibility of the CB and its coupled vibrations with the heavy equipment mounted near its center are in need.

The paper describes mechanical joining methods used in car body production. The automotive industry is a decisive industry and a driving force for the development of the Slovak economy. Mechanical connecting is the most widely used method of connecting materials. Joints are a critical factor in the production, assembly and service of cars. The joining in car body is mainly used to join material with various thicknesses, mechanical properties, surface coatings, even ferrous or nonferrous metals. Many requirements are placed on the body of the car, the important thing is sufficient stiffness of the structure under the given stress. The paper deals mainly with welded and glued joints in the design of automotive structures and their strength analysis using the finite element method. [ABSTRACT FROM AUTHOR]

The effects of the subsequent treatment of car body under different protection voltages after equipment shutdown, the energization time during previous electrocoating, and the immersion time during downtime on the anticorrosion performance of car body were studied by simulation tests. Some countermeasures and suggestions were given to reduce the number of vehicles scrapped after failure. [ABSTRACT FROM AUTHOR]

Product variants and engineering change requests challenge the automotive body shop and make flexible production systems necessary to sustain competitively. Component-integrated fixture feature (CFF) can enable flexible production by reducing specific jig and fixture technology and integrating their functions in components to be joined. This research paper presents digital twin simulation modelling of a flexible and fixtureless production concept by coupling a physical production cell in a virtual production environment. The effect of CFF on the welding process, production equipment, integration planning, and engineering changes can be forecasted for better decision-making and production planning. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The continuous development of materials and manufacturing processes, especially in the field of multi-material design, leads to a large number of different car body component designs, which are difficult to keep track of. For this reason, this article deals with the systematic derivation of generic car body components and their characteristics- and properties-based categorization. The aim is to provide a design catalogue that allows access to the collection of generic body part solutions by making use of component characteristics or properties. This allows the selection of designs from a large pool of solutions in line with requirements at a very early stage of product development. [ABSTRACT FROM AUTHOR]

Catia V5 is a reference program in the field of computer-aided design which offers an integrated solution, in addition to common solid-state modelling features characteristic to all representative applications. Furthermore, it puts at disposal stylistic modules available to specialists, allowing the development of computer usage even in pre-construction stages. This paper presents the main design steps and the 3D representation of a car body using the design leading software, Catia V5. Two subassemblies are considered, front part and passenger compartment. General considerations of surface generation in automotive car body design are highlighted. Sketching modules were used in order to create the conceptual sketch, in which the required geometries for the solids were drawn, the Part Design module, in which the solid parts of the car body were made, the Assembly Design module, the module in which the car body components were imported and assembled, the Sketch Tracer module, a module in which real-world scale shots are imported to create a custom concept, and the Freestyle module, in which the 3D lines of the car body were drawn, after which the areas for surface generation were filled.

A design study of automatic line-to-production of a new generation of car body structures compliant with the Industry 4.0 concept is described in this paper. The line is based on the hot-stamping technology of components of a car body structure from 22MnB5 steel sheets. Additional modules of the designed production line are: laser-trimming station, station to completion (kitting-up), and spot-welding station of the subassemblies. Technical requirements to be complied with by such line and scheme of exchange of information between modules of the line were defined. The conclusions were formulated.

A vehicle-track rigid flexible coupling-dynamic model is established. The first five vertical vibration natural frequencies of system are solved. The medium wave track irregularities are taken as the excitation. The car body vertical harmonic response vibration characteristics are analyzed. It could be concluded that the second-order natural frequency is the sensitive response frequency. The car body vertical vibration simulation calculation is analyzed under vertical medium-wave track irregularity with influence factors of ballast bed, including the ballast bed vibration mass, ballast-subgrade linear and nonlinear stiffness. Through a large number of simulation analysis and Da Cheng railway test verification, it is observed that when the ballast bed thickness is between 0.35 m and 0.65 m, the amplitude of car body vertical vibration acceleration is maximum, and the stronger the bed thickness suddenly changes, the greater the acceleration of vibration increases. When the ballast bed thickness is not enough, the car body vertical vibration acceleration increases obviously. The physical correlation between two tests is established for the first time through the correctness of car body vertical acceleration data of track inspection that is verified by ground penetrating radar ballast detection. [ABSTRACT FROM AUTHOR]

Abstract Due to the coating feature and bandgap adjustability of dual-base locally resonant phononic crystal (LRPC), the purpose behind this paper is to explore the application of dual-base LRPC in vibration reduction of car body. In previous research, the band structure and its influencing factors of dual-base LRPC have been investigated theoretically. As an artificial periodic structure, the key factors of application, including the number of unit cells, the curvature of base panel and the boundary constraint, have been taken account into analyzing bandgap characteristics of dual-base LRPC by finite element method (FEM). The results indicate that the non-infinite dual-base LRPC structure with small curvature and boundary constraint can still produce the expected bandgap. Then, according to the acoustic contribution analysis, the floor has been determined as the target panel for vibration reduction, on which the dual-base LRPC has been conducted. In order to obtain the wider bandgap with less added mass, the lattice constant and stiffness have been matched and optimized. With the final arrangement, the total body vibration level sharply reduces by 15 dB, and the interior noise reduces by 9 dB as well. It provides a new method for the vibration reduction of car body. [ABSTRACT FROM AUTHOR]

Availability, sustainability, and functionality pose particular challenges for the value chain of individual mobility. Therefore, in this work, the typical value chain is broken up and the traditional approaches are extended with an open-source perspective. The focus is on modularity and simplicity in order to enable the broadest possible applicability and fast implementation of local production. Nevertheless, the mobility concept should meet the current standards, especially with regard to safety. A modular vehicle frame is presented as a basis, which meets all regulations, can be built in self-assembly, and is available as open-source.

The effects of temperature, pH, and ash content of electrocoat bath and the dosage of high-boiling-point additive in it on the roughness of electrocoat were examined experimentally. Some measures to improve the roughness of electrocoat were discussed. [ABSTRACT FROM AUTHOR]