Frank Nehuis

Future Trends in the Development of Vehicle Bodies Regarding Lightweight and Cost

Lightweight design has become relevant to a lot of industry sectors, due to the wish to improve the CO2 balance of their products and to save resources. To reduce the weight of a vehicle there are different approaches to lightweight design, e.g. material substitution or lightweight construction types. These existing approaches are reaching their limits with conventional materials. For this reason lightweight materials like fibre-reinforced plastics are becoming more and more popular. However, these materials are very cost intensive. Therefore, these materials are generally used, in sports cars or in premium vehicles. In order to solve the conflict between vehicle costs and weight reduction, new lightweight approaches have to be developed for mass production. The opportunities of new materials can only be provided for a large group of customers through new approaches. One such approach is to combine fibre-reinforced plastics with the existing metallic materials. This is called multi-material or hybrid design. In this approach, the advantages of the two types of material are used for a specific application. Only then the lightweight potential can be used effective and at reasonable cost. For a vehicle, the multi-material design can be used in particular for designing the body in white. Here, almost every component can be considered by the new lightweight approach. Hybrid materials, for example, can increase the stiffness and reduce the weight of a rocker at the same time. For this the load cases of the rocker need to be analysed for which the load frequencies and amplitudes are needed. Also the life expectancy has to be determined in order to design a component with thin-walled sections as well as a minimal safety factor. Afterwards the material combination of the hybrid material is determined with respect to the load cases. Generally the fibre-reinforced plastics are placed in areas with tensile stress. Vice versa metallic materials are placed in areas with compressive stress. For designing the components ideally direct load should exist. In this case, the maximum potential for lightweight design can be used. The new lightweight approach will be developed within the Open Hybrid LabFactory together with research institutes and industrial companies. For this purpose, we gratefully thank the Federal Ministry of Education and Research for funding the research project.

Clustering Regional-Specific Requirements as a Methodology to Define the Modules of a Car Concept

The increasing globalization in the automotive industry creates worldwide new target groups. Because of that, regional-specific requirements have to be considered in the vehicle development process. This increases the complexity in conception of the vehicle’s design. In order to create vehicles economically the depth of production must not go up disproportionately. To develop systematically various factors in the vicinity of a vehicle and further to demonstrate them, in relation to the technical characteristics of a vehicle concept, a model was created in the early stages of the developing process. Finally the characteristics will be clustered to so-called ‘prototypes’, which also summarize required similar characteristics from the customer. In this case the prototypes represent a compromise between the large numbers of regional-specific alternatives and less economical ones.

The Effects of Regional Specific Requirements on the Development of Vehicle Concepts

Changes in markets and technology of automobiles amplify the issue of fulfilling the requirements for as many customers as possible with a new vehicle concept. An increasing development of regional markets demands vehicle concepts or derivatives, which fit to the customer’s wishes and satisfy the regional specific needs.

Integration of eLCAr Guidelines into Vehicle Design

Road transportation contributes considerably to environmental concerns like the increase of greenhouse gases in the atmosphere. As the world population grows and urbanization increases, outdoor air pollution becomes another environmental concern. In this context, it is a great challenge to meet mobility needs in an ecologically sound manner. Electric vehicles (EVs) are one solution to achieve this goal depending on the electricity mix in use. To support decision makers minimizing the environmental impacts of EVs, a detailed analysis and assessment over the entire life cycle is necessary. A suited method is Life Cycle Assessment (LCA). This approach accounts for all relevant flows and estimates the environmental impact of a product. Calculating the LCA of an EV encompasses challenges. For example, defining the correct system boundaries particularly for the comparison with other technologies is very significant to achieve fair and comparable results. Changes made to a single component can have multiple impacts on other components of the vehicle leading to a high complexity and the necessity to handle these interdependencies. The E-Mobility Life Cycle Assessment Recommendations (eLCAr) guidelines have been developed to help the LCA practitioner to overcome these challenges when assessing the environmental impact of EVs. In order to improve the performance of EVs regarding environmental criteria, the environmental impacts must be considered during the design phase of the vehicle. Against this background, an integrated approach is presented which includes the LCA method and the eLCAr guidelines in the design phase.

Development of a Modeling Language to Connect Features, Functions and Components☆

Abstract In order to select the components for a technical system, a detailed description of the systems features is necessary. For this purpose feature-trees are currently preferred. By selecting features from these feature-trees the corresponding components are chosen. Within the development process it is also useful to describe the functions of the technical system as well and to associate these functions with the components. For this functional-networks are used so far, which describe the dependencies between the different functions. But feature-trees and functional-networks are considered separately and not associated with the components within one model. For this reason, the features and functions of a system are usually chosen in advance. So there are two independent ways to choose components for one product. By evolution and reusing of existing components it is possible to create systems with new features or functions. If it would be possible to describe feature, functions and components within one language, proposals for new components could be made. In this paper an approach for describing features, functions and components with one language is introduced.

Anforderungsmanagement und Werkzeuge für Leichtbauweisen auf dem Weg zum Multi-Material-Design

Durch die jahrhundertelange Erfahrung in der Entwicklung und Herstellung von Fahrzeugen entsteht das Auto, wie es heutzutage auf unseren Strasen zu sehen ist. Die vermeintlichen Erwartungen des Fahrers und der Passagiere an ein Fahrzeug werden haufig durch die Summe aller Anforderungen beschrieben, die andere Fahrzeuge in der Vergangenheit erfullt haben. Das Ergebnis ist eine schrittweise Verbesserung in jeder neuen Fahrzeuggeneration. Durch die Veranderung wichtiger Fahrzeugkomponenten, wie z. B. Ersetzen des klassischen Verbrennungsmotors durch einen Elektromotor oder die Einfuhrung neuer Werkstofftechnologien, werden die Anforderungen und die Beziehung zwischen ihnen erheblich beeinflusst [1]. Das Uberdenken traditioneller Fahrzeugkonzepte erfordert auch eine Neubewertung der in der Vergangenheit gewachsenen Anforderungskollektive. Auserdem mussen in einer globalisierten Welt die Unterschiede und Unsicherheiten verschiedener Markte und Regierungen in einem gemeinsamen Modell abgebildet werden, damit Einflussfaktoren (Fahrzeug Entwicklungserfahrung, Systemkomponenten, Anforderungen, Zukunftsszenarien) beschreibbar werden und der Entwickler eine Methode und ein Werkzeug erhalt, um fundierte Entscheidungen zu treffen.

Methodology for the Objectification of Decisions in the Product Development

In order to develop the best possible product enterprises have to consider multiple solutions during the product engineering process. In early phases of the product development process enterprises generally reduce the number of possible solutions by focusing only on a few solutions to minimize development time and costs. However, in the early phases enterprises are not able to make an objective choice for the best possible product, because of missing information. To evaluate multiple solutions and nevertheless develop a cost effective product the enterprises have the aim to simplify and to objectify the decision process especially in the early phases of the product development process. Therefore the enterprises need a methodology to enable objective decisions.