Vehicle Assembly Research Articles

Reforming a conventional vehicle assembly plant for job enrichment

Although conventional conveyor-based vehicle assembly systems have proved to be very efficient in terms of plant productivity, it has also been recognized as a system which puts too much pressure on people. This paper introduces an alternative to conventional conveyor-based assembly lines, one that is designed to enrich the work environment of employees without sacrificing productivity. The reforming methodology suggested here applies the idea of cell manufacturing to the conventional conveyor-based assembly line system, but it does not require making any major changes to the existing hardware configurations of the plant. Benefits of the reformed line for workers include a longer cycle time, more balanced work loads, and greater protection against developing musculoskeletal disorders. To prove the effectiveness of the suggested methodology, we built a virtual factory model and performed simulations to assess the performance of the reformed line.

What Is the Right Supplier Park for Your Supply Chain?

The establishment of supplier parks (i.e. the co-location of component suppliers in the immediate vicinity of the vehicle assembly plant) is a relatively recent phenomenon in the automotive industry. The first supplier park officially labeled as such was opened in Abrera, Spain, in 1992 to supply the nearby Seat assembly plant. Since then, more than 40 parks have been established, predominantly in Europe and newly industrialised countries. Although significant differences between individual supplier parks can be observed, a consistent classification of colocated supplier clusters is still lacking. Given that the benefits of different supply chain configurations are contingent upon various internal and external factors, this lack of classification poses an important gap in the existing debate. This article pursues three objectives: first, to ground this discussion by providing a consistent classification of the various forms that co-located supplier operations can take, second, to investigate the dependencies between the form of supplier parks and product- and supply chain-related factors like product architecture and demand uncertainty, and finally, to assess the suitability of the different forms of supplier parks for various supply chain configurations.

The robustness of dynamic vehicle performance to spot weld failures

Spot welds are the dominant joining method in the vehicle assembly process. As the automated assembly process is not perfect, some spot welds may be absent when the vehicle leaves the assembly line. Furthermore, spot welds are highly susceptible to fatigue, so that a substantial number may fail during the vehicle lifetime. The scope of this paper is twofold. First, the impact of spot weld quality and design on a vehicle's functional performance is reviewed, addressing strength and stiffness, NVH and durability as performance attributes. The overview briefly covers both experimental tests and predictive finite element modeling approaches. Second, an industrial robustness study is presented that assesses the effect of spot weld failure on dynamic vehicle characteristics. Damaged models are generated automatically by breaking a subset of the vehicle's spot welds, using a (weighted)-uniform selection probability. Monte Carlo simulations are then used to assess the scatter on dynamic vehicle characteristics.

Logística e troca eletrônica de informação em empresas automobilísticas e alimentícias

Este artigo analisa impactos na logística pela troca eletrônica de informações entre empresas (com uso de EDI - Electronic Data Interchange e Internet), destacando a diferença destes impactos em empresas das indústrias alimentícia e automobilística. As empresas são pressionadas por parceiros para adoção destas tecnologias: a montadora é a responsável na cadeia automobilística e o grande varejo é o disseminador na cadeia alimentícia. O EDI pressupõe relações contratuais entre as empresas. As processadoras de alimentos observaram redução de erros e no tempo dos ciclos de pedido, assim como melhoria na visibilidade dos estoques e no planejamento de transporte para distribuição de seus produtos. Já nas empresas da indústria automobilística, os impactos são mais significativos no tempo e custo de processamento de pedido, com redução nos níveis e custo de estoque e de transporte para suprimento. Os resultados são de pesquisa de natureza qualitativa - estudos de casos.

USING CULTURAL ALGORITHMS TO RE-ENGINEER LARGE-SCALE SEMANTIC NETWORKS

Evolutionary computation has been successfully applied in a variety of problem domains and applications. In this paper we discuss the use of a specific form of evolutionary computation known as Cultural Algorithms to improve the efficiency of the subsumption algorithm in semantic networks. We identify two complementary methods of using Cultural Algorithms to solve the problem of re-engineering large-scale dynamic semantic networks in order to optimize the efficiency of subsumption: top-down and bottom-up. The top-down re-engineering approach improves subsumption efficiency by reducing the number of attributes that need to be compared for every node without impacting the results. We demonstrate that a Cultural Algorithm approach can be used to identify these defining attributes that are most significant for node retrieval. These results are then utilized within an existing vehicle assembly process planning application that utilizes a semantic network based knowledge base to improve the performance and reduce complexity of the network. It is shown that the results obtained by Cultural Algorithms are at least as good, and in most cases better, than those obtained by the human developers. The advantage of Cultural Algorithms is especially pronounced for those classes in the network that are more complex. The goal of bottom-up approach is to classify the input concepts into new clusters that are most efficient for subsumption and classification. While the resultant subsumption efficiency for the bottom-up approach exceeds that for the top-down approach, it does so by removing structural relationships that made the network understandable to human observers. Like a Rete network in expert systems, it is a compilation of only those relationships that impact subsumption. A direct comparison of the two approaches shows that bottom-up semantic network re-engineering creates a semantic network that is approximately 5 times more efficient than the top-down approach in terms of the cost of subsumption. In conclusion, we will discuss these results and show that some knowledge that is useful to the system users is lost during the bottom-up re-engineering process and that the best approach for re-engineering a semantic network requires a combination of both of these approaches.

A Method for Measuring the Efficiency Gap between Average and Best Practice Energy Use: The ENERGY STAR Industrial Energy Performance Indicator

SummaryA common feature distinguishing between parametric/statistical models and engineering economics models is that engineering models explicitly represent best practice technologies, whereas parametric/statistical models are typically based on average practice. Measures of energy intensity based on average practice are of little use in corporate management of energy use or for public policy goal setting. In the context of companyor plant‐level indicators, it is more useful to have a measure of energy intensity that is capable of indicating where a company or plant lies within a distribution of performance. In other words, is the performance close to (or far from) the industry best practice? This article presents a parametric/statistical approach that can be used to measure best practice, thereby providing a measure of the difference, or “efficiency gap,” at a plant, company, or overall industry level. The approach requires plant‐level data and applies a stochastic frontier regression analysis used by the ENERGY STARTM industrial energy performance indicator (EPI) to energy intensity. Stochastic frontier regression analysis separates energy intensity into three components: systematic effects, inefficiency, and statistical (random) error. The article outlines the method and gives examples of EPI analysis conducted for two industries, breweries and motor vehicle assembly. In the EPI developed with the stochastic frontier regression for the auto industry, the industry median “efficiency gap” was around 27%.

Changing Work Systems, Changing Social Relations? A Canadian General Motors Plant

This article presents some findings of an ethnographic case study on social relations in an existing vehicle assembly plant where the traditional drag chain has been replaced by Swedish automated guided vehicle technology and some aspects of Japanese work organization have been implemented. The findings challenge claims that Fordism is being replaced by a fundamentally new production model, and that this is resulting in more fulfilling work and cooperative social relations. There are many continuities with Fordism and highly contradictory social relations. This and other studies of new work Systems suggest, in fact, that contradictions between control and commitment, rather than being minimized or dissolved, can actually be heightened.

Adaptive control of automotive electronic throttle

An electronic throttle is a DC servo drive which positions the throttle plate, thus providing drive-by-wire control of engine torque. This paper presents an electronic throttle control strategy consisting of a PID controller, and nonlinear friction and limp-home compensators. The emphasis is on the development of an adaptive control strategy, which is aimed to enhance the control strategy robustness with respect to process parameter variations, caused by production deviations, variations of external conditions, and aging. The adaptive strategy consists of auto-tuning and self-tuning algorithms. The auto-tuner provides automatic tuning of the control strategy parameters during vehicle assembly, or uses specific drive modes during normal use (e.g. each time the engine is turned off). The self-tuning algorithms are based on the permanent, on-line estimation of those process parameters which can vary within a single engine run (e.g. the DC motor armature resistance). The presented adaptive control strategy has been verified experimentally.

The Locational and Functional Behavior of U.S. Autoparts Suppliers

The free trade agreement with Mexico was expected to help U.S. autoparts suppliers move southward to take advantage of low labor cost, but this has not yet happened. We can find explanations for this rather perplexing phenomenon through analyzing the outcome of a postal survey conducted just before the North American Free Trade Agreement (NAFTA) went into effect. The responses from the suppliers highlight the apparent hierarchy in the lean produc-tion system and its impact on the location choices of the parts-manufacturing firms. Despite advances in transportation and telecommunication technologies, the need to maintain short distance with respect to customers is still the single most important consideration in their decision-making. Given the reluctance on the part of the vehicle assemblers, a mass migration of suppliers to Mexico seems unlikely, although it is true that they are quite attracted to the low wages offered south of the border.

Vibrational reduction system for automotive vehicles

A vibration reduction and damping system for use in automotive closure panels, such as doors, lift gates, or other operable hatches comprising an intrusion device and an expandable material, such as a polymer-based foam, disposed along at lease a surface of the intrusion device prior to final assembly of the vehicle by the vehicle manufacturer. The system is activated as the vehicle undergoes the final vehicle assembly process, which activates and transforms the expandable material, preferably during an automobile paint operation, to expand, bond and fill the door assembly structure for vibrational damping and noise reduction.

Fumes-to-fuel system turns Ford’s waste paint exhaust into power

Ford Motor Company and Detroit Edison have jointly developed a new ‘Fumes-to-Fuel’ System that, instead of incinerating paint fumes from a vehicle assembly line, turns them into hydrogen that can be used in fuel cells. The new system has been patented by Detroit Edison in the US, and internationally by Ford and Edison. This is a short news story only. Visit www.re-focus.net for the latest renewable energy industry news

Fire protection pumps installed at Jaguar production plant

A new range of fire protection pumps and associated equipment has been installed at Jaguar Car’s Halewood production facility in the UK, where the prestigious new Jaguar X-Type car is manufactured. The fire pumps were selected because they enable prompt, reliable and effective fire control in the facility’s vehicle trim and assembly line, which processes up to 100,000 vehicles a year.

Globalization and supply chain networks: the auto industry in Brazil and India

AbstractThe automotive industries of emerging markets were transformed in the 1990s by trade liberalization and large investments by global assemblers. The impact of these investments was decisively influenced by government policies aimed at promoting local production and assembly of vehicles and by changing assembler—supplier relationships in the global auto industry. The cases of Brazil and India show how the assemblers created new linkages between operations in emerging markets and their global operations through the adoption of follow design and follow sourcing policies. These policies were hard to implement in practice, but they decisively transformed the components industries in both countries.

Delivering the ‘3-day car’—the strategic implications for automotive logistics operations

It is now becoming apparent that the current ‘stock-push’ vehicle supply in the automotive industry by fulfilling the large majority of orders from existing stock is no longer a viable proposition. Cost pressure from rising stock levels in the market and high discounts needed to sell these vehicles have forced vehicle manufacturers to rethink their order fulfilment strategy in favour of stock-less ‘build-to-order’ systems. More responsive order fulfilment at vehicle manufacturer level however will not only require flexible and responsive component supply and vehicle assembly, but will also have wide ramifications for all logistics operations in the auto supply chain. Based on findings of the 3DayCar research programme, this paper compares the implications on inbound, outbound and sea transportation logistics, leading to the development of a strategic framework for future automotive logistics operations.

Impact of trade liberalization on the location of firms: NAFTA and the automobile industry

This study investigates the short-term impact of NAFTA on automobile production patterns by constructing a multiregional monopolistic-competition model, which accommodates three types of vehicle assembler and two classes of vertically linked parts supplier. By revealing the changes in potential profits of the firms in each region, the partial equilibrium model allows us to identify the types of automobile that will most likely be produced in Mexico as a result of reductions in tariffs and non-tariff barriers. The simulation results indicate that as trade barriers fall, ceteris paribus, producers of small cars will find it more desirable than large-car manufacturers to operate in Mexico. Recent developments seem to support the results of this model.

Reliability and Validity of Questionnaire for Assessing Physical Workloads

Objectives: The aims of the study were to make a questionnaire for assessing physical work - loads and to evaluate its reliability and validity. Methods: A total of 220 workers (foundry workers 30, large vehicle assemblers 30, shipyard workers 75, and automobile manufacturers 80) completed a self-administered questionnaire and took examinations for physical work capacity and working heart rate. We excluded data with insufficient responses or incorrect physical work capacity and working heart rate. Finally, the data of 154 workers (70.0%) were used for our study. In order to evaluate the reliability and validity of the questionnaire, we used statistical analyses including the scaling assumption test and a comparison with the objective tool for physical workload which was evaluated by work - ing energy expenditure. Results: The items of the questionnaire in the same categories had close distribution in the evaluation of the scaling assumption. The item internal consistency was 0.41-0.73 for posture factor, and 0.62-0.79 for non-posture factor. The item discriminate validity was 100%. Cronbach' sαcoefficient of the total items was 0.73 (0.58 for posture factor and 0.74 for non- posture factor). In the correlation between working energy expenditure and questions, general physical activity (p=0.008), proportion of the workday with hands above shoulder (p=0.002), proportion of the workday with trunk bent (p=0.028), proportion of the workday with awkward posture (p=0.048), sweating after work (p=0.006), total scales (p=0.003) and Borg scale (p=0.011) all had statistical significance. Conclusions: Our questionnaire for assessing physical workloads demonstrated statistically significant reliability and validity. But the questions for the proportions of the workday with sit - ting work posture and with static posture should be modified via a larger study.

VW’s modular system and workers’ organization in Resende, Brazil

This article discusses the changes taking place in the Brazilian vehicle assembly industry of the 1990s with particular reference to the state of Rio de Janeiro, Brazil. It focuses upon a case study of Volkswagen’s bus and truck assembly plant, opened in 1996, and its workers at Resende. The experience of the `modular system’ of production has been presented as a major development in vehicle assembly. The article analyses the originality of VW’s new form of organization of production and the strategy of the firm to look for localities with weak labour unionism. It also argues that despite the difficulties the local union faced in its attempts to intervene in the process of wage bargaining and to influence the management of aspects of production, there has been a rapid process of mobilizing the new workers for effective labour union action.L’article traite des transformations intervenues dans l’industrie automobile brésilienne dans les années quatre–vingt dix, avec une attention particulière pour l’Etat de Rio de Janeiro. Il s’attache à l’usine d’assemblage que Volkswagen ouverte en 1996 à Resende pour y assembler des véhicules industriels. Cette expérience de production modulaire a été présentée comme une innovation organisationnelle majeure dans l’industrie automobile mondiale. Le texte met en évidence les spécificités de la nouvelle organisation de la production et la stratégie de localisation de la firme fondée sur la recherche d’espaces d’implantation à faible activisme syndical. Il montre que malgré sa faiblesse initiale et une intervention réduite dans la négociation salariale et l’organisation du travail, une mobilisation rapide des nouveaux travailleurs a permis la reconstitution d’un mouvement syndical actif.

Kistler reusable vehicle facility design and operational approach

Kistler Aerospace Corporation is designing and developing the K-1, the world's first fully reusable aerospace vehicle to deliver satellites into orbit. The K-1 vehicle test program will be conducted in Woomera, Australia, with commercial operations scheduled to begin shortly afterwards. Both stages of the K-1 will return to the launch site utilizing parachutes and airbags for a soft landing within 24 h after launch. The turnaround flow of the two stages will cycle from landing site to a maintenance/refurbishment facility and through the next launch in only 9 days. Payload processing will occur in a separate facility in parallel with recovery and refurbishment operations. The vehicle design and on-board checkout capability of the avionics system eliminates the need for an abundance of ground checkout equipment. Payload integration, vehicle assembly, and K-1 transport to the launch pad will be performed horizontally, simplifying processing and reducing infrastructure requirements. This simple, innovative, and cost-effective approach will allow Kistler to offer its customers flexible, low-cost, and on-demand launch services.

Molecular vehicles for targeted drug delivery.

Targeted drug delivery by cell-specific cytokines and antibodies promises greater drug efficacy and reduced side effects. We describe a novel strategy for assembly of drug delivery vehicles that does not require chemical modification of targeting proteins. The strategy relies on a noncovalent binding of standardized "payload" modules to targeting proteins expressed with a "docking" tag. The payload modules are constructed by linking drug carriers to an adapter protein capable of binding to a docking tag. Using fragments of bovine ribonuclease A as an adapter protein and a docking tag, we have constructed vascular endothelial growth factor (VEGF) based vehicles for gene delivery and for liposome delivery. Assembled vehicles displayed remarkable selectivity in drug delivery to cells overexpressing VEGF receptors. We expect that our strategy can be employed for targeted delivery of many therapeutic or imaging agents by different recombinant targeting proteins.

Knowledge transfer of the Western concept of quality

This paper addresses one of the issues in contemporary globalization theory: the extent to which there is 'one best way' in which business can be conducted and organizations managed. It uses Czarniawska's 'travels of ideas' model as an organizing framework to present and understand how the concept of 'quality', so important in contemporary approaches to manufacturing and services, and their management, travelled to, and impinged on, a newly opened vehicle assembly plant in Poland. The extent to which new meanings were mutually created in the process of translation is discussed, using ethnographic reporting and analysis techniques commonly used in diffusion research. Parallels between the process of translation as an idea becomes embedded into a new cultural location and the processes which contemporary research has identified as important to organizational learning are briefly discussed in conclusion.