The work thesis was performed at Assalub a company which is situated in Åtvidaberg. The company works with developing, manufacturing and marketing equipment for handling of lubricants for light and heavier industry. The work thesis it is based on a inquiry Assalub got from MacGregor which is a company within cargo solution, from port to offshore system.

For unloading grain and other material from the ship cargo it is used combined inlet feeder and screw conveyor, there the inlet feeder is drilling down through the cargo and feed the screw conveyer with material to further destination. At the bottom of the screw conveyer and the inlet feeder there is a bearing that keep the parts together. However the lubrication of the bearing must be made manually. Until now the bearing was lubricated manually through a grease nipple from the bottom of the drill once a day.

The purpose of the thesis was the construction of a lubricating system namely a pump with a grease container which should be placed inside the space of the screw conveyer, so the bearing will be continually lubricated and able to work several days without any stoppage.

After receiving drawings and operating data for the screw conveyer, the details for the construction was designed in CAD system Solid Edge. The solid mechanics calculations on the weakest point on the construction was made by hand and afterwards the drawings for respectively details was made.

The construction was completed, but because of the time limit for this work thesis, the manufacturing, mounting and testing were not included in these weeks. The grease containers capacity is approximately seventy-two hours, although desirable should be up to seven days. According to the solid mechanics calculations, the construction should have no problem to resist the stresses it would be exposed to.

Since this is a prototype there is probably some adjustments and improvements to do, but the estimating is that the system should work properly as it is now.

The effects of mobile telephone use on traffic safety is discussed in the article. A number of empirical studies are reviewed and it is concluded that the use of a mobile telephone concurrently with car driving may have a negative impact upon traffic safety. The sub-tasks of entering a telephone number and having a demanding conversation are especially likely to increase the risk of an accident. To minimize the negative impact from telephoning on traffic safety a number of recommendations are suggested.

We investigate the internal strain and crystallographic orientation (texture) in physical-vapor deposited metal nitride coatings of TiN and CrN. A high-energy diffraction technique is presented that uses synchrotron x rays and an area detector, and which allows the strain and intensity distributions of multiple crystallographic planes to be measured by a single x-ray exposure. Unique texture states and nonlinear sin2 ψ strain distributions are observed for all coatings investigated. Quantitative analysis indicates that existing micromechanical models can reasonably predict strain and corresponding stress for mixed-hkl reflections but are inadequate for fully describing measured data. Alternative mechanisms involving deposition-induced defects are proposed.

The relationships between coating microstructure and properties in the Cr-C-N system have been investigated as a function of composition and post-deposition annealing. Coatings of varying compositions were grown using arc-evaporation, by varying the reactive gas flow ratio fR = f(C2H4)/f(N2) from 0 to 0.2, and were found to consist primarily of the cubic d-Cr(C,N) phase. Changes in both the unstressed lattice parameter, ao, and X-ray diffraction background intensity indicate that both the carbon concentration within the d-phase and amorphous/crystalline content increases with fR. Increasing fR also decreases the magnitude of the compressive biaxial residual stress, from approximately 6 to 1 GPa, while increasing both the inhomogeneous stress and thermal stability. The elastic modulus and hardness of as-deposited coatings were determined from nanoindentation to be 320 and 23 GPa, respectively, for moderate carbon concentrations (fR=0.05). Concurrent variations in microstructure and hardness with post-deposition annealing indicate that the as-deposited hardness is significantly enhanced by the microstructure, primarily by lattice defects and related stresses (microstresses) rather than average stresses (macrostresses).

Cr-N coatings were arc-deposited at 50 and 300 V. The changes in the coating microstructure and phase content during tempering were monitored. As a result, the phase stability and activation energies for defect diffusion were determined as a function of ion energy.

Gas turbines are used where large amounts of energy is needed, typically as engines in aircraft, ferries and power plants. From an efficiency point of view it is desirable to increase the service temperature as much as possible. One of the limiting factors is then the maximum allowable metal temperatures in the turbine stages, primarily in the blades of the first stage, that are exposed to the highest gas temperatures. Specially designed materials are used to cape with these severe conditions, such as the nickel base superalloy IN792. In order to be able to design the components for higher temperatures and tighter tolerances, a detailed understanding and computational models of the material behaviour is needed.

The models presented in this work have been developed with the objective of being physically well motivated, and with the intention of avoiding excessive numbers of parameters. The influence of the parameters should also be as easy as possible to interpret. The models are to describe the the behaviour of IN792, under conditions typically found for a gas turbine blade. Specifically the high- and intermediate- temperature isothermal modelling of IN792 have been addressed.

One main issue when characterising the material and calibrating the models is the use of relevant tests, that are representative of component conditions. Therefore isothermal tests with an eye on the typical environment of a turbine blade have been planned and performed.

Using numerical optimization techniques the material parameters for the isothermal behaviour of IN792 at 650°C and 850°C have been estimated. The good overall calibration results for these specific temperatures, using the presented modeling concept and nonstandard constitutive tests, suggests that the model can describe the behaviour of IN792 in gas turbine hot part applications.

The material parameters for two isothermal viscoplastic models with deliberately limited sets of material parameters have been estimated. The models are to describe the behaviour of the nickel based superalloy IN792 in a gas turbine hot part application. The models are based on a power law flow equation and the state variable used is backstress. The model calibration is done by least-squares optimization using non-standard constitutive tests that are aimed at describing relevant component conditions. The constitutive tests give information about the kinematic hardening effects for the backstress evolution equations, while secondary creep data provides stress versus inelastic strain rate information for the flow equation. All tests are uniaxial and isothermal. With the estimated parameter sets the models give relatively good fits to the data. The results suggest that the models can be used to describe the high temperature behaviour of IN792. ⌐ 2002 Elsevier Science B.V. All rights reserved.

Aircraft design is an inherently multi-disciplinary activity that requires different models and tools for various aspects of the design. At Linköping University a novel design framework is being developed to support the initial conceptual design phase of a new aircraft. Different modules are included, each one addressed to analyze and evaluate different aspects of the airplane, such as its aerodynamics, its weight and structure, its sub systems and its performances. All modules are easily accessible from a user-friendly interface based on an Excel spreadsheet. The link between all modules is based on Service Oriented Architecture (SOA) and allows both distribution and integration of all functions. This paper will present the framework, give an overview of its development status and give an indication on the future work.

The overall aim of this thesis is to increase the understanding of the relationship between standardised environmental management systems (EMSs) and the environment, focusing on the use of such systems by companies and on systems in accordance with the ISO 14001 and/or EMAS standards. Another purpose is to investigate how standardised EMSs fit small and medium-sized enterprises (SMEs) and to examine a special EMS solution called the Hackefors model, used by a group of SMEs, to find out how this model has affected the environmental efforts and business of these enterprises.

To gather knowledge on the connection between EMSs and environmental impacts, two main roads have been followed. Firstly, empirical studies (and a few literature reviews) have been conducted, among other things, aiming to clarify how the standards' requirements are interpreted and applied in reality, and uncover what this means in terms of environmental impacts. For the most part, external environmental auditors and environmental managers have been interviewed. An important purpose is to illuminate what an ISO 14001 certificate, or an EMAS registration, guarantees. This means that the minimum level is emphasised to a large extent. Secondly, a literature review has been conducted to collect knowledge on the selected issue from the international research arena. One intention is that this review will contribute information about the average use of EMSs and thus serve as a good complement to the empirical studies.

It has to be concluded that a standardised EMS does not guarantee a good environmental performance and defmitely not reduced environmental impacts. Without any doubt, EMSs can be used to structure and strengthen a company's environmental efforts, and many companies surely have achieved important reductions in terms of environmental impacts by using an EMS. However, the standards' formulations are very indistinct and they can be interpreted and applied in many different ways. It is clearly possible to be certified and registered without improving very much at all. The effects of EMSs are to a very large extent dependent on how companies choose to use them. To capture the potential that EMSs have, issues of credibility should be observed. Therefore, the thesis includes some recommendations in the form of discussion points.

The Hackefors model clearly can be used to overcome many of the common barriers forimplementing an EMS at SMEs. In the studied case, the EMS implementation had led to severalimportant environmental improvements and also to other types of improvements.

This thesis aims to increase the understanding of what a standardised environmental management system (EMS) is, can be, and is not. The EMS infrastructure, i.e. the standards for EMSs and corresponding systems for their application, is analysed to find out how"ft affects the environmental efforts of companies. Furthermore, the topic of how standardised EMSs fit small and medium-sized enterprises (SMEs) is discussed. A special EMS solution used by a group of SMEs is examined to clarify how this model has affected the environmental efforts and business of these enterprises.

The thesis is based on three studies. Firstly, external environmental auditors were interviewed. Secondly, the environmental reviews for the group of SMEs were studied. This study also involved a literature review on how to measure environmental performance. Thirdly, the environmental co-ordinators working at the mentioned small enterprises were interviewed.

It can be concluded that it is too early to draw any general conclusions on how standardised EMSs affect environmental performance. How ISO 14001 is interpreted and applied is largely left to companies and external environmental auditors. In practise, 14001's requirement concerning continual improvement is often restricted to a few environmental aspects and does not say anything about the total environmental impact. Furthermore, there is an inconsistency in the standard text and its implementation concerning which criteria are approved when assessing environmental aspects. Some auditors allow the inclusion of criteria regarding economy and quality, etc. To ensure the credibility of ISO 14001, the standard and the systems for its application should be improved.

The EMS model studied seems to be a cost-effective solution for SMEs that removes the most important barriers for EMS implementation and maintenance at small firms. Also, it appears to have led to significant environmental improvements.

Small and medium-sized enterprises (SMEs) are an important group from an environmental point of view and they also have environmental requirements - including environmental management systems (EMSs) - imposed on them by larger companies. At Hackefors Industrial District in Sweden, 30 SMEs are co-operating on environmental issues; they have formed a network and established a joint EMS in accordance with ISO 14001. This is a unique strategy for the implementation of EMSs by SMEs. In this paper the EMS model used at Hackefors is presented and the resulting cost savings are analysed. Environmental improvements are also discussed briefly. It can be concluded that, by networking and implementing a joint EMS, the SMEs (mostly small and 'micro' enterprises) at Hackefors have established a rational and cost-effective solution that has facilitated both the implementation and maintenance of EMSs. Although the EMSs have only recently been certified, many environmental and commercial improvements have already been observed. Many of the companies have received positive responses from their customers and believe that the EMS improves their ability to obtain contracts relating to sales of products and/or services. Furthermore, the companies at Hackefors believe that having an EMS based on ISO 14001 results in positive commercial and environmental effects.

This paper discusses the connection between standardized environmental management systems and environmental performance, based on a case study. By comparing the environmental reviews for a group of small and medium-sized enterprises (SMEs) before and two years after their EMS implementation, we try to show how the environmental performance of these firms has developed and draw some conclusions regarding the connection between standardized EMSs and environmental performance in general.

The case study illuminates some central aspects of ISO 14001's requirement of continual improvement. Taken together with the literature on this issue, it is clear that in practice a set of indicators are established and monitored, indicators concerning operations as well as management efforts. Hence, the selection of indicators is crucial. External environmental auditors should compare the development of these indicators and determine if an improvement has occurred or not. Naturally, this judgement by auditors is very important and difficult. The situation is very similar to the weighting step recognized as a problem in life cycle analysis, but the use of indicators for management efforts adds an additional dimension to this already intricate problem.

In Hackefors Industrial District in Sweden, 26 small and medium-sized enterprises (SMEs) have formed an environmental network and implemented a joint environmental management system (EMS) according to ISO 14001. Based on interviews with the environmental co-ordinators at these enterprises, the effects on business and environmental efforts and impacts are analysed.

It can be concluded that the joint EMS has resulted in better relations with important stakeholders, such as existing and potential customers. For example, three-fifths said that their EMS had made it easier to receive a contract for the sale of products and services. Several environmental improvements have been observed and are presented in the paper, many of which are considered as consequences of the EMSs. Moreover, based on observations during the study, this paper discusses how boundaries and screening affect the connection between EMSs and environmental performance.

The ISO 14001 standard leaves a lot to be interpreted by its users. As the standard is growing in popularity the external environmental auditors are becoming key players in the environmental arena. Through interpretations, they form the linkage between the standard document and its application in reality.

This study is based on interviews conducted with auditors representing all nine certification bodies in Sweden and at the board that accredits these firms. The paper presents how auditors interpret and apply central requirements of ISO 14001, with the aim to illuminate important issues from an environmental point of view.

It can be concluded that many important requirements are interpreted differently. There are disagreements regarding what criteria are approved when determining which environmental aspects are significant. Further on, the standard's requirement for continual improvement is normally transformed to improvements regarding a few ratios. The paper, amongst other issues, also deals with auditors' competence, their objectivity and their opinions about the efforts of certified organizations.

En hydraulisk riktningsventil av "öppet-centrum"-typ med ett ventilhus och en i detta rörlig vetilslid för reglering av flöde av hydraulfluid genom ventilen har en tryckkompenseringsventil anordnad i minst en för anslutning till en driven anordning avsedd arbetport för att tryckkompensera flödet från arbetsporten till den drivna anordningen.

Det här föredraget behandlar olika systemprinciper för att styra en variabel pump i en mobil applikation. Variabla pumpar med elektrisk styrning ger möjlighet till nya intressanta systemprinciper.

Many real-world engineering design problems involve the simultaneous optimization of several conflicting objectives. In this paper, a method combining the straggle genetic crowding algorithm with Pareto-based population ranking is proposed to elicit trade-off frontiers. The new method has been tested on a variety of published problems, reliably locating both discontinuous Pareto frontiers as well as multiple Pareto frontiers in multi-modal search spaces. Other published multi-objective genetic algorithms are less robust in locating both global and local Pareto frontiers in a single optimization. For example, in a multi-modal test problem a previously published non-dominated sorting GA (NSGA) located the global Pareto frontier in 41% of the optimizations, while the proposed method located both global and local frontiers in all test runs. Additionally, the algorithm requires little problem specific tuning of parameters.

The aim of this paper is to implement sensor control in wood carving operations. The introduction of wood carving is a step towards the development of a new manufacturing method for the wood manufacturing industry, where wood carving would facilitate increased freedom of the design choice. A control method that improves robot control and supports simpler programming, based on using an industrial robot equipped with a wrist mounted force/torque-sensor. is proposed for the wood carving process. This paper describes the structure and control algorithm of the system and how different machining parameters affect the cutting forces. The evaluation of the system showed that it is possible to control the cutting depth at speeds up to 7.5 mms by adjusting the rake angle of the tool to obtain a nominal force.

This paper presents. the usage of a multi-objective genetic algorithm to a set of engineering design problems. The studied problems span from detailed design of a hydraulic pump to more comprehensive system design. Furin] thermore, the problems are modeled using-dynamic simulation models, response surfaces based on FE-models as well as static equations. The proposed method is simple and straight forward and it does not require any problem specific parameter tuning. The studied problems have all been successfully solved with the same algorithm without any problem specific parameter tuning. The resulting Pareto frontiers have proven very illustrative and supportive for the decisionmaker.

This thesis focuses on how to improve design and development of complex engineering systems by employing simulation and optimization techniques. Within the thesis, methods are developed and applied to systems that combine mechanical, hydraulical and electrical subsystems, so-called multi-domain systems. Studied systems include a landing gear system for a civil aircraft, electrohydrostatic actuation systems for aircraft applications as well as hydraulic actuation systems.

The usage of simulation and optimization in engineering design is gaining wider acceptance in all fields of industry as the computational capabilities of computers increase. Therefore, the applications for numerical optimization have increased dramatically. A great part of the design process is and will always be intuitive. Analytical techniques as well as numerical optimization could however be of great value and can permit vast improvements in design.

Within the thesis, a framework is presented in which modeling and simulation are employed to predict the performance of a design. Additionally, non-gradient optimization techniques are coupled to the simulation models to automate the search for the best design.

Engineering design problems often consist of several conflicting objectives. In many cases, the multiple objectives are aggregated into one single objective function. Optimization is then conducted with one optimal design as the result. The result is then strongly dependent on how the objectives are aggregated. Here a method is presented in which the Design Structure Matrix and the relationship matrix from the House of Quality method are applied to support the formulation of the objective function.

Another approach to tackle multiobjective design problems is to employ the concept of Pareto optimality. Within this thesis a new multiobjective genetic algorithm is proposed and applied to support the design of a hydraulic actuation system. The outcome from such a multiobjective optimization is a set of Pareto optimal solutions that visualize the trade-off between the competing objectives. The proposed method is capable of handling a mix of continuous design variables and discrete selections of individual components from catalogs or databases.

In real-world situations, system parameters will always include variations to some extent, and this fact is likely to influence the performance of the system. Therefore we need to answer not only the question "What is best?", but also "What is sufficiently robust?" Within this thesis, several approaches to handle these two different questions are presented.

In this paper, a new multiobjective genetic algorithm is employed to support the design of a hydraulic actuation system. First, the proposed method is tested using benchmarks problems gathered from the literature. The method performs well and it is capable of identifying multiple Pareto frontiers in multimodal function spaces. Secondly, the method is applied to a mixed variable design problem where a hydraulic actuation system is analyzed using simulation models. The design problem constitutes of a mixture of determining continuous variables as well as selecting components from catalogs. The multi-objective optimization results in a discrete Pareto front, which illustrate the trade-off between system cost and system performance.

This paper presents a method where a multi objective optimization techniqueis used together with response surface methods in order to support crashworthiness design. As in most engineering design problems thereare several conflicting objectives that have to be considered when formulating a design problem as an optimization problem. Here this is exemplified by the desire to minimize the intrusion into the passenger compartment area and simultaneously obtain low maximum acceleration during vehicle impact. These two objectives are naturally conflicting, since low maximum acceleration implies large intrusion. The contribution of thispaper is to show a successful application of a set of existing methods to solve a real world engineering problem.The paper also presents methods of illustrating the results obtained from the multi-objective optimization.

The work presented in this thesis deals with information sharing within mobile robot teams. Main focus is on information related to team positioning and localization. The goal of this research is to find models for how to best deploy a group of robots.

The motion platforms covered are well adapted. although very important for the results. Motion models are crucial when calculating the dead reckoning of each platform. Results in the appended work show that the motion model has heavy impact on the possibility to affect the uncertainty of a robot team as new ground is deployed.

The sensor models discussed may not necessarily be what is commonly used in the research field. Instead good approximations are used, that describe the main features of the sensor type. The focus is to present different sensor types and describe how the characteristics affect the uncertainty of the robot team, not to create new sensor models. A general model for sensors with polar measurement coordinates is derived. This can be used with different sensors with the same characteristics.

A framework for sharing information within the robot team is derived. This is based on earlier work presented as "The Stochastic Map". However, the framework is tailored to suite the purpose of this work. Different estimation methods are also discussed, with main focus is on Kalman filtering techniques.

The resulting part of this work present different ideas of what should be considered when deploying a group of robots. Results show how different dist ribution of sensors will affect the localization uncertainty of the group. It is also shown how different deployment formations affect the uncertainty within the team.

When dealing with robot localization and simultaneous map building one of the greates problem is to keep the created map consistent. Due to linearization, simplifications and other errors in models resent work has shown that the map created will, eventually, diverge. One way of dealing with these problems is to present the map in robot coordinates and thereby increase the consistency of the map. In the case many robots are used to create a map collectively this consistency problem often arises even sooner. This work propose a new method of dealing with the consistency problem when doing collaborative mapping by presenting the map in a groupcentric coordinate frame that continuously moves together with the robot team as new areas are explored.

A standard IRB (Industrial Robot) of today is not capable of positioning itsels to within better than 2-5mm relative to a given structure or object. In order to be able to perform high precision manufacturing, the requirement is less than 0,5mm. Existing solutions for 6DOF measurements to enhance the accuracy are not only expensive but also lacks flexibility. An affordable, accurate concept for IRB closed loop position feedback is presented here. This article proposes a method for using a camera together with fixed features to enhance the accuracy of an IRB in industrial manufacturing processes. The method is based on SLAM (Simultaneous Localization and Mapping), used to structure collected information about the features (mapping), and for the IRB to locate itself among the features (localization). The concept covers a scenario in which a set of features are placed within the working area. A camera is mounted on the IRB to observe (measure) the relative pose of the feature set. When the system is running observation of only one feature increases accuracy. However, in normal operation more features are observed which will increase accuracy further. The system setup is a standard IRB, ABB4400, on which a single camera with IR flash is mounted and used as sensor. The features are made out of reflectors that are placed in the production cell. The camera is also equipped with an IRfilter to improve the signal to noise ratio, simplifying image processing and accelerating execution. The execution time is critical since the goal is to sample at such rate that as to cover the dynamics of the robot. 

Contains a collection of invited papers dedicated to the memory of two great mathematicians, Gaetano Fichera and Panagis Panagiotopoulos. The book is centered around the seminal research of G Fichera on the Signorini problem, hemivariational inequalities, nonsmooth global optimization, and regularity results for variational inequatities.