A database for finite element models and related data is developed and incorporated into a prototype system for integration of non-linear finite element codes with a product design system. In the prototype system, the database is used as a link for integrating commercial, public domain as well as in-house codes. In the present system, the public domain finite element codes NIKE2D, NIKE3D, DYNA2D, DYNA3D and TOPAZ2D are integrated with the CIM-system I-DEAS. The prototype system is primarily intended as a platform in research projects for development of integrated environments tuned for simulations of specific manufacturing processes such as quenching, welding, hot rolling, metal powder compaction and hot isostatic pressing

In the design of high temperature components, design evaluation often requires an iterative procedure between thermal fluid and thermal structural simulations An integrated computer system providing an iterative environment for the multidisciplinary simulations re quired has been developed. The system supports iterations between thermal fluid and thermal structural simulations using two different commercial simulation packages. Traditionally, fluid and structural analysis have been simulated separately and analysis of coupled prob lems has required special, multidisciplinary simulation packages which are seldom used in early stages of design. Improving the infrastruc ture for data exchange between separate computer applications is one way to significantly reduce the lead time for design iterations. This reduction in lead-time allows multidisciplinary effects to be accounted for in early stages of design. The design system is demonstrated on an exhaust manifold, where the thermal interaction between fluid and structure is of significant importance. The commercial simulation tools have been integrated to demonstrate the effect of automised data flow on design methodology, i.e , de sign iterations. This integration method makes use of existing features in the simulation packages and uses an export file format as the neu tral exchange format. In this way, the integrated system is simple and fast to develop which is preferred in small prototype systems and de velopment project Database integration supports a tighter integration, but requires more development effort. For design systems, where several design tools need to communicate, standardised information management procedures are preferable, following the ideas of the STEP framework.

This paper provides a specification of a relational data base structure for mechanical systems. Through the example provided, a robot gripping device, it is demonstrated how the initial development of the data-base structure has successfully led to an implementation in a practical software environment. The data base is accessible to multiple engineering application programs and supports a flexible environment for the continuing development of new applications

The success of engineering companies is highly dependent on how well product information is managed, engineered and communicated. From marketing through development to after sales activities, data needs to be accessible and used in the best way. Today, geographical distance, the need for close co-operation and data complexity are all natural parts of the working environment. Product modelling techniques are continuously evolving with new requirements and opportunities emerging daily. This paper will outline and discuss some of these trends, and at the same time present some of the areas where research is being carried out within projects in the Product Model Cluster in the national graduate school - The Swedish Engineering Design Research and Education Agenda (ENDREA).

This thesis comprises six papers dealing with implementations and techniques for linking computer-aided applications for design and analysis into a concurrent engineering environment. Each paper deals with a part of the environment - together they constitute an integrated design system for concurrent engineering. Concurrent engineering requires applications across all functions within the company to share and communicate information. The applications used in the product development process need to be linked together. This thesis examines the linking, of applications using databases. In Papers A, B, C, D and F this linking is studied using a relational database. In Paper E an object-oriented database is investigated. Using database technology proved to be an efficient way of linking applications together. In Papers A, C, D and E databases for geometric data, measurement instructions, mechanical systems, computational fluid dynamic and finite element data have been developed as part of a general concurrent engineering environment. In Papers B, E and F the general concurrent engineering environment has successfully been used for performing simulations of manufacturing processes and product performance as well as the verification of the shape of products manufactured by hot isostatic pressing. Solid models have been used throughout all the work as the foundation for the product definition. The solid models can be used by many downstream functions and provide an efficient base for the geometric definition and associated information such as analysis models and probe paths for coordinate measurement inspections.

This paper presents a computer-integrated system for design, manufacturing simulation, and inspection using a coordinate measurement machine (CMM). The work is concerned with the problem of predicting the shape of the container for hot isostatic pressing (HIP) and it focuses on the verification of a finite element (FE) simulation model for HIP. The verification is performed by comparing the simulated geometry of a real component produced by HIP. The geometry of the HIP component is measured by a CMM. The whole process from design and manufactunng simulation to inspection and geometry verification is performed within a computer-aided concurrent engineering (CACE) system. The system is built on both commercial and non-commercial software. The communication between a CMM, a geometnc modelling system, and the finite element simulation codes is developed. The manufacturing of a turbine component to net shape geometry using HIP is chosen as a demonstrator example. The benefits of the presented CACE system are time and cost savings as well as higher product quality.

Trends of more team working and cross-functional activities in Integrated Product Development increases the requirements on the computer-aided engineering technology used. Experience of using solid models in a product development project at Volvo Aero is presented. Further, it is described how thermal boundary conditions, calculated using Computational Fluid Dynamics simulations, can be integrated with thermal structural analysis in a commercial Finite Element code. It is argued that incremental technology development using technology based on international standards, e.g., the STEP standard, is a low-risk, highly efficient strategy for improving multi-functional analysis systems.

Providing not only products but a combination of products and services can help add value and enable competitiveness for both the providers and their customers. Research has suggested Functional Products (FP) as one concept to achieving this combination of products and services.Traditionally, when a product is sold the ownership of the product is transferred to the customer, making it difficult for the provider to access information from the products use phase. In the case of FP, the ownership of the product is retained by the provider, and access to use phase information is essential to provide the function at a guaranteed level of availability. This information access also allows feedback to earlier life cycle phases. This paper explores how information generated in the use phase of FP can be integrated with the virtual product representation in a Product Lifecycle Management (PLM) system.A concept was developed for capturing use phase information from a potential FP. The concept utilizes wireless sensors that makes the information available through networks. WebSockets are used for providing real-time access and visualisation of the information. Both real-time and historical information can be accessed in a dashboard by any device that supports HTML5. A PLM system connects relevant information from the FP in use with the virtual representation of the FP.The concept was implemented in a case at a producer of automotive parts. A unified solution for information management of both use and development of FP was achieved by integrating use phase information and the virtual product representation

This paper features the implementation and evaluation of a proposed approach for information capture and representation integrated into the existing design environments at two manufacturing companies. A tool has been developed that automatically derives information from the CAD system during design and provides users with the means to capture product information that has previously been documented outside of the CAD system. Product information is managed in a PLM data model and becomes, once stored, the foundation for providing tailored views of information.Feedback from the evaluation shows that the prescribed approach was preferred to the current one and that it would likely provide value to users, both authors and consumers, of product information. This approach can reduce the time required to capture the pertinent product information. However, the primary savings are likely to be indirect as a result of increased consistency, understanding, and the potential (re)use of product information.The approach and tools presented constitute another step toward providing each stakeholder with more efficient, intuitive, contextual, and purposeful support for information capture and representation in computer-aided product development.

The amount of product and process related information in the engineering industry is large and constantly growing. Methods and tools are therefore needed to effectively leverage the information, ensuring that it is readily available, contextually understandable and usable for the activity at hand. This paper presents findings from two cases performed at manufacturing companies and an approach for how information effectively can be utilized during the development and lifecycle of a product. The approach primarily addresses the lack of up-to-date information, free of redundancies and accessible from the context where it is needed or will be captured.

New business models and more integrated product development processes require designers to make use of knowledge more efficiently. Capture and reuse are means of coping, but support, techniques, and mechanisms have yet to be sufficiently addressed. This paper consequently explores how computer-aided technologies (CAx) and a computer-aided design (CAD) model-oriented approach can be used to improve the efficiency of design module capture and representation for product family reuse. The first contribution of this paper is the investigation performed at a Swedish manufacturing company and a set of identified challenges related to design capture and representation for reuse in product family development. The second contribution is a demonstrated and evaluated set of systems and tools, which exemplifies how these challenges can be approached. Efficient design capture is achieved by a combination of automated and simplified design capture, derived from the design implementation (CAD model definition) to the extent possible. Different design representations can then be accessed by the designer using the CAD-internal tool interface. A web application is an example of more generalpurpose representation to tailor design content, all of which is managed by a product lifecycle management (PLM) system. Design capture is based on a modular view block definition, stored in formal information models, management by a PLM system, for consistent and reliable design content. It was, however, introduced to support the rich and expressive forms of capture and representation required to facilitate understanding, use, and reuse of varied and increasingly complex designs. A key element in being able to describe a complex design and its implementation has been capture and representation of a set of design states. The solution has been demonstrated to effectively be able to capture and represent significant portions of a step-by-step design training material and the implementation of complex design module through a set of design decisions taken. The validity and relevance of the proposed solution is strengthened by the level of acceptance and perceived value from experienced users, together with the fact that the company is implementing parts of it today.

Through the Centre for Automotive Systems Technologies and Testing, Luleå University of Technology aims to first of all support automotive winter testing in Northern Sweden. This means to support the local automotive test entrepreneurs and through them their customers: the car manufacturers and their suppliers. To succeed in this task, the center relies on the university's areas of leading research and most importantly on the cooperation between those areas.

The work has demonstrated how the conceptual design process can be improved by allowing the seamless and automated sharing of geometry information between a commercial CAD system and a commercial one-dimensional Computational Fluid Dynamics code for the purpose of fluid dynamics analysis of exhaust systems. The driver for this work was the need to carry out conceptual aero-acoustic design of an exhaust system where the simulation model included the intake, engine, and exhaust system. The exhaust system is modeled in the fluid dynamics domain using parameterized building blocks. The integration achieved via the pre-processor developed makes it possible to associate these building blocks with the solid geometry defined in the CAD system and to use this connection to determine their geometric parameters.

For rotordynamic analysis of hydropower units, the generator is treated as a rotating rigid body. However, previous studies have confirmed that certain designs of generators are elastic, so the complex geometry of generators cannot be considered rigid. This work produced a model of hydropower generators with floating rotor rims, consisting of a rigid hub and a flexible rotor rim coupled with flexible connections. The model takes into account the influence of centrifugal and Coriolis effects, and the electromagnetic interaction between rotor and stator. The model also reproduces the dynamics of the generator with static and dynamic eccentricities. A generator prototype was employed to test the model, showing its different applications. Once validated by empirical data, this model could be used when designing generators.

Hydropower generators withstand multiple forces from diverse sources during operation. To ensure their stability and safe performance, numerical tools are developed to characterize their dynamic properties. Traditionally, generators are assumed to be rigid in rotordynamic analyses. However, the measurements in power stations challenge this assumption. This article proposes a novel approach to modeling hydropower generators with floating rotor rims using a three-dimensional (3-D) Finite Element Method, aiming to study their dynamic performance and properties, including natural frequencies, the modes of vibrations, and expansion due to centrifugal and electromagnetic forces, with the goal of improving the reliability of modern designs. Both this approach and employing a two-dimensional (2-D) model using curved beams result in similar in-plane natural frequencies and the expansion of the rotor rim due to centrifugal forces. However, the 3-D model can be used to calculate the out-of-plane natural frequencies and modes, to model the dynamics of complex geometries, and to perform stress evaluation and fatigue analysis.

In this paper we propose a model for collaboration between engineers in a distributed environment based on a suite of specialized computer tools. The system is built around the distributed virtual reality system DIVE that has been customized for interoperability with existing CAD systems. Other tools supporting the information exchange process in a product development project include audio/video conferencing software, shared workspace systems for document sharing, application sharing tools, shared whiteboard applications and more. The paper discusses the components of the collaboration environment both from a technical standpoint as well as in respect to usability issues.

In this paper a modular numerical simulation model for hybrid powertrains is presented. The simulation model is based on common design parameters and measurements for fuel efficiency and vehicle performance. Implemented in Simulink, the main model is expandable to combine the strengths of different types of simulation tools. As the design process proceeds, parts of the model can gradually be replaced with instances containing one or more subsystem modelled in the appropriate tool, including CAD, FEA and MBD, incrementally increasing the accuracy of the model of the overall system yet keeping the simulation time reasonable. Subsystems can be replaced to support hardware input and/or output, resulting in a so-called hardware-in-the-loop simulation. The presented system has shown to be modular as all the components contain their physical properties and can be modified, replaced or reorganized without the modification of any other subsystem. The simulation model of the powertrain is easily modified in order to allow the simulation of multiple designs with the same components. The systeam also has the same information flow as would be observed in a physical powertrain.

Ride comfort is an important aspect of any passenger vehicle. The challenge is to provide a comfortable, yet safe, ride for the driver and the passengers and there is often a trade-off between ride comfort and safety performance.In the case of small wheelchair-accessible vehicles the challenge increases. The weight of a wheelchair with person may span from 50 kg to 500 kg, which means that the suspension must be tuned to have a broad working range. Also, a wheelchair-accessible vehicle has many restrictions on design space and tuning possibilities due to, e.g., the space needed for the wheelchair passenger to get in and out of the vehicle. Hence, there is an additional need to evalute ride comfort and performance before the vehicle is built in order to find the optimal design. Traditionally, this is done by computer simulations of vehicle handling complemented with testing followed by chassis tuning prior to production. However, some performance parameters regarding comfort, especially in the case of wheelchair passengers, are still not well investigated and documented, and there is a need to subjectively evaluate the ride comfort in early design phases.In this paper we investigate the use of a motionbase simulator as a platform for evaluating ride comfort with different suspension setups. We are using a reversible sleeve air suspension bellow equipped with an adaptor cylinder giving the spring characteristics. The characteristics of four different adaptors have been measured in a universal test machine. The force-compression characteristics are imported into the simulation. The simulation model used is a half-car, two-degree of freedom producing bounce and pitch movement data for either the driver or the passenger positions. The data from the simulations are used as input to a motionbase simulator for subjective assessment of the ride comfort.The primary results indicate that a motionbase simulator can be a useful tool when designing/developing suspension systems. Also, the results indicate that a motionbase simulator is useful for investigation of comfort parameters in order to determine objective assessment of subjective parameters.

During road travel, obstacles can impede productivity or durability for many different vehicles and render discomfort or injuries for the people within. Using remote sensing techniques, information from the surroundings can be acquired and analysed to identify obstacles ahead. The subsequent analysis can create a decision support for how the vehicle or driver should act upon encountered obstacles, through either autonomous control, guidance to the driver or a combination of both. In this paper, an experimental setup was created to mimic an obstacle in the shape of a speed bump on a flat road. An RGB-D camera was used to acquire information while travelling towards the speed bump. Afterwards, the acquired information was analysed by an estimation of the normal vector for each point in a 2D depth map. The resulting data from the experiments had sufficient resolution, speed and quality to retrieve proper identify obstacles or targets indoors with an accuracy of 2%. Obstacles were measured and identified in less than 20~ms where processing time mainly comprised data transfer from the USB-bus. The obstacle identification can be used to e.g. actively control the vehicle suspension, send feedback to the driver about obstacles ahead or optimise speed and direction for autonomous vehicles.