Aspects of material selection and innovative concepts of car construction using aluminium as best suited light-weight materials were presented, and recent development in established and advanced use ...of aluminium in passenger cars was discussed that help to meet economic and environmental requirements. 5xxx and 6xxx aluminium alloys were presented that have been improved for the increasing demands regarding higher strength and better formability, resulting in a mass reduction and improved crashworthiness. Furthermore, advances concerning multi-material light weight design were presented by examples for aluminium solutions in advanced “Multi-material” Super-Light-Car (SLC) concepts, which reaches significant mass reductions.
•A BIW weld quality inspection method using vibration response signals has been proposed.•The LGHGNN model is designed for intelligent detection of BIW weld quality.•The cluster upgrade graph pooling ...is proposed to elevate node features.•Hierarchical information interaction and collaborative output.•Parallel anomaly detection for multi-label corresponding to multiple regions.
To enhance the assembly quality in Body-in-White (BIW) assembly, this paper proposes an intelligent detection method for the nugget quality of Resistance Spot Weld (RSW) based on weld joint vibration excitation response signals. The method proposes a novel deep learning model, the Local-Global Hierarchical Graph Neural Network (LGHGNN). LGHGNN can automatically construct graph structures and, by introducing a newly designed upgrade pooling operation, extends the traditional flat structure of graph networks into a hierarchical structure within three-dimensional space. Therefore, LGHGNN achieves layered interaction of local-global information, enabling the model to focus on local details while gaining a broader learning perspective. Additionally, this paper proposes a strategy for multi-label unsupervised anomaly detection that involves layered interaction and collaborative decision-making for local and global graphs. The effectiveness of LGHGNN is demonstrated through its application in the BIW right front door assembly, achieving a remarkable 97.5% average accuracy in multi-region parallel anomaly detection.
A tailor welded blank (TWB) have been consistently used for manufacturing of car bodies worldwide. TWB is a blank in which different sheets of metal with various thicknesses are welded together. The ...main aim of this is to reduce the total mass of the vehicle which in turn improves the fuel efficiency of the vehicle, power requirements and good crashworthiness by replacing the conventional metallic blanks by TWB, which is extensively used in automobile industries. The main objective this paper is to provide the latest innovations carried in this field which will be further used in body in white (BIW) of vehicles.
A life cycle assessment (LCA) study is performed to compare the life cycle primary energy demand (PED) and global warming potential (GWP) of steel baseline automotive body-in-white (BIW) with three ...types of lightweight Scenarios. Scenario I, Scenario II, and Scenario III use advanced high strength steel (AHSS), aluminum alloy (Al alloy), and carbon fiber reinforced plastic (CFRP), respectively. China Automotive Life Cycle Database (CALCD), onsite data of Chinese automotive industry in 2015–2017 and process models are used for inventory analysis in this study.
The results indicate, among the different lightweight Scenarios for the BIW, the Scenario II provides the lowest PED and GWP during a lifetime travelling distance of 200,000 km. Scenario I shows the best break-even distance. Scenario III presents lower PED and GWP relative to the base case; however, it does not reach a breakeven for GWP within the lifespan of 200,000 km.
Sensitivity analysis results depict that a combination of longer lifetime distance, larger fuel consumption and smaller substitution ratio is beneficial for lightweight BIW Scenarios, especially for Scenario III, to achieve the largest PED and GWP reduction compared to the baseline in the full life cycle.
•The durability analysis of the vehicle body by considering spot weld failures.•Consideration of inertia effects by utilizing a mode-based dynamic analysis.•Thickness-dependent nugget diameter for ...the spot welds.•Discovering the effect of different standardized driving maneuvers on the failure life of the spot welds.•Analyzing the effect of the nugget diameter on the fatigue life of the spot welds.
Durability of the vehicle components needs special attention in the design step due to this fact that the loads on a vehicle are dynamic by their nature. Also, fatigue resistance of the vehicle body is quite important as it is the main load-bearing component among others. The main purpose of the present research is to simulate the spot weld failures of the vehicle body structure due to fatigue damage induced on the body during standardized maneuvers. This was accomplished by using a combination of multi-body dynamics and finite element analyses. To enhance the precision of the analysis, a thickness-dependent nugget diameter was utilized to model the spot welds. To validate the finite element simulations, three-sheet spot-welded specimens were tested and their fatigue lives were compared to numerical results. The findings of this study revealed that the damage to the vehicle body is not always proportional to the vehicle velocity and that depends on the degree of road roughness. Also, the results of simulations showed that the damage to the front part of the body is almost twice the rear part in terms of the number of spot weld failures. The effect of nugget diameter on the fatigue life of the spot welds was also investigated and it was found that the nugget diameter can change the fatigue life of the spot welds up to almost 100%.
Front Impact and Side Impact are the major cause of passenger injuries in car accidents. Passenger safety is the important criteria while designing the automotive Body In White (BIW). Side Door ...Intrusion Beam is one of the main energy absorbing part in event of side impact. This work focuses on comparative study of three cross-sectional profiles, three gauges and three materials for side door intrusion beam. A detailed numerical & experimental study has been performed to analyze the static and dynamic behavior of different cross section profiles, gauges & materials of side door intrusion beam in the event of side impact. Comparative study of side door intrusion beams has been made to find out the force reaction and energy absorption capacity of the beam to protect the occupant from the side collision by using FEA software. Taguchi method is used to determine the optimized design parameter by using static analysis of FEA model on three point bending simulations. Optimal design of side door intrusion beam with optimal energy absorbing capacity and resistance force is validated on three point bending experimental test. The Effectiveness of the optimal door beam design is verified on full vehicle side impact simulations.
•This work focuses on comparative study of 3 cross-sectional profiles, 3 gauges and 3 materials for side door intrusion beam.•Taguchi method is used to optimized design parameter by using FEA model on three point bending simulations.•The Effectiveness of the optimal door beam design is verified on full vehicle side impact simulations.
In this paper, the welding parameter model of resistance spot welding (RSW) of body-in-white(BIW) Al alloy plate was studied in details, and the key welding parameters that influence the RSW quality ...are analysed in-depth. Based on the concept of equivalent plate thickness (SV), simplification of nugget volume and thermodynamic theories, combined with the properties of Al alloy, the mathematical models of welding current, pressure, time were established through production data and test verification. These models reflect the relationship between key welding parameters and equivalent plate thickness. The welding current and pressure are linear with SV, and the expressions are different when SV is greater than 2. For welding pressure, there exist two critical curves according to the different yield strength of welding materials. The yield of the material lies in between and pressure can be chosen between two critical curves. The welding time is directly linear to the actual thickness of the plate. Actual welding parameters can be obtained by the models and least test, which is very important for decision of welding parameters rapidly.
The assembly process of a car body-in-white (BIW) in a body shop is a very important link in complete vehicle manufacturing process, and BIW dimension quality control is the most important part of ...BIW quality control. The quality-related fixture fault diagnosis problem is proposed in smart dimension control loop established in BMW Brilliance Automotive company (BBA) aiming to detect locating fixture fault, which could seriously influence BIW dimension quality. This article introduces a novel statistical quality-related fault diagnosis method by combining Kalman filter and generalized likelihood ratio test, making system innovation as a basic fault diagnosis tool and establishing a hypothesis test between fixture-fault-free model and fixture-faulty model to detect potential fixture fault, meanwhile estimates fixture fault occurred station by maximum likelihood estimate. The fixture fault diagnosis flowchart is built to decrease false and missing alarm rate in actual production process. The case study based on the real BIW component assembly process data from BBA demonstrate that this fault diagnosis method can accurately post fixture fault warning and send correct order to on-site workers to maintain locating fixture in a batch of products.
The product development process within the automotive industry is subject to changing and varying demands due to external influences and internal strategic decisions. Influences and decisions, such ...as a shift from hybrid vehicles to fully electric architectures, turn into explicit requirements. For a manufacturer to remain competitive, these requirements need to be fulfilled within the early design phases of the development process. The car body substructure and body shop in particular have the highest interdependence with the automotive product development process. To reduce the resulting complexity of managing various requirements for each car body type, car manufacturers use modular design to create partitioned subassemblies. Although there is a wide range of strategies for the modularization of individual requirements, none of them offers the possibility of considering multiple influences and identifying interdependencies between formed modules. To solve this problem, we provide a structured approach for the early planning and design phases as means of achieving this multi-criteria modularization. We transform results from the requirement elicitation into dependency matrices to weight, compare and synchronize critical and relevant requirements. Thus, it is possible to analyze interdependencies to gain knowledge for the design of new product and production modules. In cooperation with the Mercedes-Benz Cars division, we validate our approach and create a domain-specific blueprint for car body substructures. Therefore, we are able to deepen the understanding, give part-specific recommendations and provide a new decomposition of modules of future vehicle architectures.
Abstract
Welding, as an important process for body-in-white (BIW), it should be taken into consideration in the automobile industry where the spot welding is often used. In order to validate the ...welding process of the whole welding line, the simulation process for the body side which is an important part of the BIW is discussed in the software Delmia according to the layout in AutoCAD which has been designed before. And then the establishment of model, the welding process and the specific working procedures are considered and discussed in the design stage to guarantee that the simulation process in Delmia can be carried on to validate whether the designed process can meet the working requirements. Additionally, the welding operation by multi-robots in a work station is analysed to verify that the number of robots and their positions are acceptable and they can reach working positions. Finally, the planning of the cycle time is obtained and then we can conclude that the designed welding process is feasible to guide the work in site.
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