Automobile Panel Research Articles

Evaluation of automobile parts design scheme for intelligent manufacturing

Aiming at the selection of modern auto parts design schemes, an evaluation method of automobile parts design scheme for intelligent manufacturing is proposed. Considered the environment-friendly factors and traditional manufacturing factors, the evaluation index system of automobile parts design scheme was established, which taken technology, environment, economy and quality reliability as the first level evaluation index, and 12 second level indexes under the first level index. The game theory method was used to comprehensively consider the proportion of subjective and objective weights to determine the composite weight of each index. Aimed at the certainty and uncertainty of the evaluation index, the set pair analysis relative closeness method was used to calculate the composite weight and established the model. Three sets of automobile panel design schemes of a company were selected, and the mathematical model was used to calculate them. With the help of C language program, the advantages and disadvantages of the three design schemes were evaluated, and the optimal scheme was obtained. The calculation example proves that the method is true and effective, conforms to the background of modern intelligent manufacturing, and the calculation is simple, and has good feasibility and practicability.

Plane bending fatigue behavior of interstitial-free steel at room temperature

Abstract Interstitial-free steels are widely used as thin sheet for automobile external panels. For this type of application, essential properties of the steel are deep-drawability and stretch-formability. However, low-strength interstitial-free steel is nearly pure iron and work on fatigue fracture behavior of this steel might be adopted as a basic study to understand the behavior of high-strength steels used for structural components. In this study, the fatigue fracture behavior of low-strength interstitial-free steel has been studied at room temperature in air and in an argon atmosphere. Fractographic observations on fatigue fracture surfaces reveal a mixed type of fracture mode (intergranular and transgranular cracking) for all specimens. The major portion of intergranular fracture has been found at the regions of low and medium crack lengths. Further increase in the crack length causes a decrease in the proportion of intergranular cracking and, finally, the fracture mode becomes completely transgranular. At the same test temperature, the proportion of intergranular fracture drastically decreased when the test was carried out in the argon atmosphere.

Production of sustainable rigid polyurethane foam from chemically modified underutilized Jatropha curcas L seed oil: Influence of polyol chemical structure on properties of polymer

Environmental awareness has revitalized utilization of bio-based resources as precursors for industrial applications. Natural lipids from plants and animals (macro and microorganisms) are among the recent sustainable resources used as alternative to petroleum-based resources in industrial applications. Bio–, petrochemical– and bio/petrochemical blend–based rigid polyurethane foams (RPUFs) were prepared from polymerization reaction between diphenylmethylene–4, 4–diisocyanate (MDI) and epoxidized/hydroxylated Jatropha curcas L oil (JCO) using a 2–shot technique. Synthesized RPUFs were characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and derivative thermogravimetric analysis (DTG). Apparent density, porosity, mechanical properties, close cell content, cell size and biodegradability were equally evaluated. FTIR analysis confirmed formation of urethane bond in the prepared RPUFs. The morphology of the synthesized RPUFs showed cellular structural size between 119.1 and 274.8 ​μm. Thermograms of synthesized JCP–based and JCP/PEG–based RPUFs from TGA/DTG curves showed that they are more thermally stable than PEG–based RPUF. Apparent density (AD) and biodegradability decreased as PEG content in polyol blends increased. The AD greater than 40 ​kg/m3 and porosity value ​> ​70% indicated potential ability of synthesized RPUFs to be useful as light material in production of automobile panel. Close cell content >80% and compressive strength greater than 300 ​kPa validated synthesized 0.4JCP–based RPUF to possess most acceptable impart absorbing property for production of automobile panel.

Implementation of Real Contact Areas into Sheet metal Forming Simulations using Digital Spotting Images

Increasing demands on quality of outer car panels and shortened product development processes fundamentally challenge automotive manufacturers. Development times are significantly influenced by the manufacturing process of dies, which are introduced by the time-consuming manual grinding operations carried out during die try-out. Blue color paste is often used to visualize contact areas between die surfaces and blank to provide a spotting image. The spotting image can be used to evaluate and optimize the pressure distribution. A homogeneous pressure distribution positively influences the forming process in terms of flange draw-in and surface quality. This paper presents an approach for implementing real contact areas into forming simulations based on digital spotting images of active surfaces. Spotting images were produced for different drawing depths and subsequently extracted by image processing. The simulation model presented in this study includes different spotting levels in conjunction with the TriboForm friction model to describe tribological conditions during forming more accurately.

Prediction and assessment of skid line formation during deep drawing of sheet metal components by using FEM simulation

The subjective perception of the quality of sheet metal components mainly depends on geometric characteristics and surface structures. In this context, particular attention must be paid to avoiding surface defects such as skid lines during the sheet metal forming process for components with high surface quality requirements (e.g. outer skin passenger car panels). In principal, FEM simulation can provide an effective tool for predicting such surface defects. However, the numerical modelling approaches available today do not yet allow an adequate basis for assessing their quality relevance in production, which especially applies to skid lines. In a previously published study, new skid line criteria were developed in this regard, considering unbending strain, thinning and major strain. Using a simple steel sheet part (DC06) as reference, the study showed that these criteria allow the quality relevance of skid lines to be predicted relatively accurately. This paper focuses on the validation of the proposed skid line criteria and their applicability to the materials DC06 and AA6016. Furthermore, the numerical studies presented show that one of the novel skid line criteria, which considers unbending strain and thinning, is able to accurately locate and predict the quality relevance of skid lines even for complex shaped parts.

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Research on multi-band structural noise reduction of vehicle body based on two-degree-of-freedom locally resonant phononic crystal

First, the dispersion curve of a two-degree-of-freedom locally resonant phononic crystal (LRPC) is calculated by the plane wave expansion method. The result shows that the structure has the characteristics of double bandgaps in the mid- and low-frequency range, which is verified by the finite element method. Then, the frequency response analysis of the interior noise and the acoustic contribution analysis of car panels are carried out, and the front left floor is found out to be the panel with a larger contribution of the peak value of noise. Therefore, the LRPC is arranged on the front left floor based on the modal strain energy, and then the total vibration level and the radiated sound power level of the panel are calculated, which are both decreased by 11 dB to 13 dB after the arrangement of LRPC. The acoustic simulation analysis of the whole vehicle after the arrangement is also carried out, which shows that the original sound pressure level peaks at 270 Hz, 346 Hz and 378 Hz are reduced by 6.2 dB(A), 5.56 dB(A) and 9.35 dB(A), respectively. The results provide guidance for the application of LRPC in the field of structural noise reduction of engineering plates.

Development of Jute Hybrid Composites for use in the Car Panels

The purpose of this research work is to explore the potential of jute composites to be used in side panels of a car as a lightweight biodegradable substitute to steel and other materials, which will result in better fuel efficiency and maneuvering capabilities. Various tests were carried out to determine the feasibility ofusing these materials to make car panels. While it has lower tensile and flexural properties than that of carbon fiber material, still it can be replaced as a cheaper alternative to carbon, since carbon is very expensive and scarce. Also, it has higher strength to weight ratio than that of steel while being cheaper than steel, which can make it a plausible option for car manufacturers to look into. But at the same time, there are some issues that are needed to be overcome.

An augmented reality approach for supporting panel alignment in car body assembly

One of the major problems in automotive assembly consists in achieving alignment within the specified tolerances between car panels that make up the exterior bodywork. To reduce errors and time requested to perform the assigned assembly tasks, workers should be guided during these panel fitting operations. Augmented Reality (AR) could be particularly suitable in this regard, as it represents one of the most promising tools to support personnel, with constantly growing applications in production processes. Following this trend, the present work aims to present an AR prototype system for supporting the operator during panel fitting operations of car body assembly, by providing instructions to correct alignment errors in terms of gap and flushness. A real case study concerning the fine alignment of car body panels with respect to the front light projector is also presented.

Numerical simulation analysis of rubber flexible die properties on forming quality of the double-curved part for 6K21-T4 aluminum alloy

The double-curved is the main feature of the sheet metal part, which is mainly used in automobile panels, aircraft skins, high-speed rail car bodies, etc. The forming process can easily lead to the local thinning and springback and seriously affect its forming quality. In this paper, the influence of the shear modulus of the flexible die on the thinning and springback of 6K21-T4 aluminum alloy for double-curved parts was analyzed by the numerical simulation method. Different rubber flexible die were selected for the forming process of the different double-curved parts, and the effect of the shear modulus on the thinning and springback of double-curved parts was obtained. Results show that the thickness reduction of the part formed by the rubber flexible die is reduced by 10.6% compared with that of the rigid punch forming. The maximum effective stress difference can be reduced by 67.4% and the springback can be reduced by 64.8% through optimizing the shear modulus of rubber flexible die.

Physical, chemical and surface morphological characterization of single areca sheath fiber

The technological advance in various streams necessitated the increased demand for lesser weight and minimal cost materials. The concerns to ensure environmental sustainability, those newer materials were expected to be decomposable. In the current study, chemical, physical and mechanical and morphological aspects of areca sheath/frond fiber are investigated. It is observed that, the cellulose, hemicelluloses and lignin wt. % are 65.02, 8.26 and 18.62 respectively. The XRD study confirms the percent crystallinity of 81.33% and the crystallinity index of 0.77. The fiber further exhibited the tensile strength of 59.62±2.20 MPa. The TGA study reveals the higher degradation rate at 322.2 °C and the residual mass at 500 °C is 33.23%. The morphological study is done through scanning electron microscopy (SEM). The other properties such as density (0.9 g/cm3), the fiber length, diameter, and moisture uptake are also reported. From the very promising results, the fiber can be used as a reinforcement agent and the composites may find potential applications in automobile panels, interiors, structural light weight bearing sheets, etc.

Analysis and optimization of idle noise caused by canister purge solenoid valve

In the development process of a certain CHINA VI proprietary brand car model, there exists the problem of intermittent “dada” sound in the cockpit during idling. After investigation, it’s determined that the air pulse noise generated when the canister purge solenoid valve is working, it is transmitted to the car panels through the pipeline, and then to the cockpit, which would cause a “dada” sound. By adding expansion chamber in the desorption pipe and designing part of the pipeline which fixed in the clamp as rubber pipe, the intensity of air pulse can be effectively reduced and the transmission path of air pulse vibration can be blocked. Through objective testing and subjective evaluation, the scheme can greatly reduce the idle noise of the cockpit, thus improving the NVH performance of the vehicle and bringing comfortable riding environment to the passengers.

A proposal of an assembly workstation for car panel fitting aided by an augmented reality device

In the automotive sector, panel fitting operations represent a delicate phase of the assembly process, during which car bodywork components are manually aligned attempting to comply with spacing tolerances. Digital technologies currently promoted by the Industry 4.0 approach, such as collaborative robots and augmented reality (AR), could assist workers for reducing execution times of this “trial and error” procedure. On the one hand, human-robot collaboration (HRC) can enhance assembly process efficiency, by combining human dexterity and cognitive capabilities with robot repetitiveness and support in heavy load handling; on the other, AR can provide interactive instructions to guide workers during the process. In this regard, the present paper is focused on the development of a novel assembly workstation using HRC and AR to support workers during car panel fitting operations. The system is based on the implementation of an algorithm able to convert the values on panel spacing, which are measured by laser gauge positioned on the collaborative robot, in the instructions for the worker to correctly carry out the panel fitting operation. The paper finally presents the application of the system to a real assembly example.

Study on Automotive Back Door Panel Injection Molding Process Simulation and Process Parameter Optimization

A plastic back door car panel was considered as the research object. In order to obtain optimal injection molding simulation parameters, Moldflow2018 is used to simulate injection molding process of plastic back door car panel. Orthogonal experiment is conducted to analyze the influence of injection process parameters on the evaluation index. Melt temperature, mold temperature, cooling time, packing pressure, and packing time are selected as process parameters. Warpage and volumetric shrinkage are taken as evaluation indicators. Test groups are designed to obtain data, and range analysis method is employed to analyze warpage and volumetric shrinkage. Warpage range analysis shows that optimal warpage is 9.3 mm for volumetric shrinkage rate of 14.3%. Range analysis of volumetric shrinkage rate indicates that the best warpage is 8.3 mm for the corresponding volumetric shrinkage rate of 15.05%. A comprehensive evaluation index is established using the gray relational analysis. This analysis shows that warpage is 8.3 mm and volumetric shrinkage rate is 14.2%. Taguchi method is employed to obtain signal‐to‐noise ratio, while range and variance methods are used for the analysis. Optimal warpage is obtained as 8.2 mm, while the volume shrinkage rate is 10.3%. For a single evaluation index warpage, least squares method and artificial fish swarm algorithm are used to find the optimal parameter combination. Moldflow2018 is employed for simulation verification, and minimum warpage is obtained as 6.405 mm.

A decision tree approach for energy efficient friction riveting of polymer/metal multi-material lightweight structures

Friction riveting has emerged out as a promising candidate for joining polymers to metals, since it is energy efficient, fast and eco-friendly without material wastage and pre and post processing and cleaning. For sustainable manufacturing of car ports, automobile panels and aircraft structures, there is a need for joining of polycarbonate to AA 6063 using friction riveting technique. Hence in the present work, Polycarbonate/AA 6063 combination is joined employing friction riveting with a new slotted end rivet. Microstructural examination reveals a visible deformation during the penetration of AA 6063 rivet that provides excellent anchoring. Decision tree is an exploration approach that is applied on friction riveting experimentation data and it has derived meaningful information out of testing data to reach the maximum possible tensile load carrying capacity by a friction riveted joint within the production constrains. The maximum tensile load of 5.75 kN can be achieved when rotational speed, friction time and depth of friction riveting are kept above at 2050 rpm, 37.5 sec and 9 mm respectively. It is helpful in industries during selection of different combination of process parameters to obtain the desirable joining strength. • Successful joining of dissimilar Polycarbonate to AA 6063. • Friction riveting with new slotted end rivet profile. • Decision tree approach, for judicial selection of processing conditions. • Micro-structural investigation on bonding mechanism at the interface.

Design and Analysis of Jig and Welding Fixture for Car Panel to Shift the Locate Pin

Design and Analysis of Jig and Welding Fixture for Car Panel to Shift the Locate Pin

Vibration analysis of metal – polymer sandwich structure incorporated in car bonnet

The weight of the car material plays an important role in its performance in terms of fuel efficiency, speed and smoke emission. Especially in hybrid electric vehicles, lightweight materials are important for balancing the weight of its electrical components and also to enhance vehicle speed on account of its comparative low mileage. Nowadays, aluminium, magnesium and Carbon Fibre Reinforced Composites (CFRP) were introduced in making of car body panels since those materials can improve its performance. Yet the material costs, fibre orientation and fabrication techniques in case of CFRP in mass production remains a question. Also, the interior of the car panels was filled with vibration barriers or isolators with considerable thickness which can also add weight to the car. Hence a sandwich structure is presented in this work where the polyurethane foam of higher thickness (core) is bonded between two thin metallic face sheets (skin). The polyurethane foam was chosen as the core because of its low density, porosity and viscoelastic behaviour where it can provide better damping capabilities. Hence, the foam can also help in reducing the volume of internal vibration isolators. Since the car bonnet receives the vibration from sources like aerodynamic exposure to air during travel and mechanical movements within the vehicle (engine operation), it was chosen as the subject for vibration analysis.

Improved Stiffness Modeling for An Exechon-Like Parallel Kinematic Machine (PKM) and Its Application

Hole drilling or contour milling for the large and complex workpieces such as automobile panels and aircraft fuselages makes a high combined demand on machining accuracy, stiffness and workspace of machining equipment. Therefore, a 5-DOF (degrees of freedom) parallel kinematic machine (PKM) with redundant constraints is proposed. Based on the kinematics analysis of the parallel mechanism using intermediate variables, the kinematics problems of the PKM are solved through equivalent kinematics model. The structural stiffness matrix method is adopted to model the stiffness of the parallel mechanism of the PKM, where the stiffness of each joint and branch component is obtained by stiffness formula and finite element analysis. And the stiffness model of the parallel mechanism is improved by correction coefficient matrix, each element of which is constructed as a polynomial function of three independent end variables of the parallel mechanism. The terminal stiffness matrices obtained by simulation result are used to determine the coefficients of polynomial function by least square fitting to describe the correction coefficient over the workspace of the parallel mechanism quantitatively. The experiment results prove that the modification method can greatly improve the stiffness model of the parallel mechanism. To enhance the machining accuracy of the PKM, the proposed kinematics model and the improved stiffness model are utilized to optimize the working stiffness of parallel machine by searching the best relative position of parallel machine and workpiece. A plate workpiece taken as example is examined in the case study section, which demonstrates the effectiveness of optimization method.

A Study on Surface Wetting and Corrosion Behavior of Straightened Car Panels

Straightening of impact damaged car panels is a common practice when damaged area is small to medium. Common car panel straightening methods are hammering, heating and welding pins and pulling on the material using a device called a spot weld puller, so that the straightened metal sheet may have, as a consequence, its microstructure, stress and strain state altered. The aim of this research was to find how the above methods alter the corrosion behavior of the alloy used for car panel manufacture. Samples from similar damaged car panels were obtained, straightened, tested and compared to a sample from an original panel. Testing implied microstructure characterization, surface wetting investigation and corrosion testing. It was concluded that when straightening is carried out by hammering and using the spot weld puller the worst corrosion behavior is to be expected.

Construction of car instrument panel design support system using eye model coupled with musculoskeletal model

Construction of car instrument panel design support system using eye model coupled with musculoskeletal model