This thesis describes a framework for the high level control of an autonomous unmanned spacecraft. Greater autonomy than currently exist is required for unmanned spacecraft to enable missions to distant planets and bodies. One reason for this is that the signal return time is too long to accommodate real-time control from the ground. A second reason is that spacecraft travelling to bodies where little is known of the environment (e.g. asteroids) must have the capability to respond to unplanned events. In addition, autonomy can help reduce mission operations costs, a very important factor in the current climate where more is expected from space missions at a lower cost. The thesis proposes a novel architecture for an autonomous unmanned spacecraft, based on Distributed Artificial Intelligence (DAI), and more specifically based on the multi-agent paradigm. The proposed model for spacecraft control is decentralised. In this architecture, the spacecraft is made up of agents; the traditional ground-based controller is one agent. The spacecraft is goal-driven; it receives high level goals from the ground. The planning and scheduling of activities to achieve these goals is carried out on-board the spacecraft. The spacecraft is also event-driven; it reacts to events that occur on-board the spacecraft as well as in the environment. A DAI architecture requires a co-ordination mechanism, and a communication structure. Also, distributed versions of algorithms must be provided. In this thesis, co-ordination with and without explicit communication and distributed scheduling were investigated, and a framework proposed for both these issues. An autonomous spacecraft must have inference capability for on-board decision making to enable it to respond to unplanned events. Probabilistic reasoning in the form of Bayesian networks was used to provide the spacecraft with the capability for on-board decision making. Situations may arise where the spacecraft must make decisions with uncertain or incomplete information. The issue of decision making with uncertain or incomplete knowledge (e.g. co-ordination without explicit communication) was investigated using domain specific scenarios. Spacecraft resources are typically very limited in capacity. On-board resource management should result in more efficient use of resources. A framework for an on-board resource manager was defined and implemented using reinforcement learning. A distributed version of the scheduling algorithm using reinforcement learning was developed. Thus, this thesis describes and investigates an architectural framework for a multi-agent approach to spacecraft control.

The work develops the application of evolutionary algorithms in the domain of automotive heat exchanger design. The principal employed is that of computer regulated changes to a physical model which attempts optimisation using methods analogous to biological evolution. It shows that the use of airside fins with differing louvre angles can enhance the performance of automotive heat exchangers by a useful margm. This has been achieved with a wind tunnel model that allows automatic configuration of the louvre angles, and novel instrumentation allowing heat transfer performance to be assessed in terms of shear and drag forces acting on the louvres. During the investigation an important coupling between the behaviour of adjacent louvres was discovered, manifested as a loss in useful shear force at around ±12° relative angle. The work as a whole shows that specific louvre angle selections and quantitative estimates of the potential performance gains could be made with the following improvements to the physical model and search algorithms. The number of louvre rows should be doubled (to 16) to better represent typical matrices and the instrumented louvres should be centrally positioned in the air stream. Improved data filtering is required for reliable operation and the specific figure of merit has been shown to be an important factor in the optimisation process. A parallel area of application for the optimisation strategies was the solution of the Wilson plot problem. This represents a novel approach to the analysis of heat exchanger experimental test data where an alternative curve fitting and visualisation format allows more accurate models to be established. By these methods functions defining heat transfer coefficients for both sides of a heat exchanger may be determined that give a fit to experimental data to within less than 1. 5% on measured overall heat transfer coefficient.

Environmental impact reduction (EIR) in Product Development processes, can involve numerous elements and activities. In relation to business objectives, the strategic review and integration of environmental impact reduction should be considered a best practice development opportunity and a contribution towards longer term sustainability. It should be recognised that environmental impact reduction requirements are often complex and challenging for businesses to implement, especially for those companies lacking the knowledge and internal resources to address these activities. This has been found to be the case particularly with Small and Medium Enterprises (SMEs) where flexibility towards new approaches can be strategically more problematic, due to the limitations of available capital and resource. After a combination of literature review, industrial collaboration and data collection from within the manufacturing logistics systems of packaging for SME products, an opportunity was identified to develop a contemporary framework to integrate key critical environmental impact reductive activities, within adjoining New Product Development (NPD) activity. Engaging key activities of environmental impact reduction seamlessly into standardised NPD though a visual mapping process, can promote changes in current behaviour towards best practice development opportunities concerning environmental impact reduction. The contribution to new knowledge from this programme of research has been the development of an investigative framework for visually mapping the product development processes which provides manufacturing SMEs with an approach to capturing „visual snapshots‟ of their current engagement within environmental impact reductive activities. This visual mapping process addresses a range of company sizes and organisational behaviours to provide specific feedback and inform best practices for more sustainable NPD.

No

Beräkningsmetoder för formverifiering av friformsytor utgör huvudinnehållet i denna doktorsavhandling. En gemensam egenskap för dessa metoder är att de möjliggör formverifiering online direkt i produktionslinan. Av den anledningen måste metoderna vara snabba och robusta. Ett av problemen som uppkommer i formverifieringen av friformsytor är registrering. Det är problemet med att matcha datapunkter i 3D-rymden, som representerar den uppmätta ytan, med ett CAD-objekt genom att ansätta en stelkropps transformation. En metod för att utföra registreringen snabbt och robust är utvecklad. Metoden är en utveckling av ”the iterative closest point method, ICP”. Vi förprocessar CAD-objektet genom att skapa en datastruktur för att möjliggöra snabb närmsta-punkt sökning. Initialt läggs mycket tid på att skapa datastrukturen för att de enskilda registreringarna skall gå snabbt. Den robusta registreringen baserar sig på teorier från robust statistik genom att tillämpa ”iteratively re-weighted least squares” i kombination med ICP metoden. Detta resulterar i en snabb registreringsmetod som är okänslig för avvikande data. Metoden med registreringen används i en tillämpning för att hitta avvikelser mellan formen för ett objekt och dess ideala form. Den ideala formen är känd och ges av ett CAD-objekt. En optisk formmätningsmetod, projicerade fransar med en enda mönsterdetektering, används för att skapa datapunkter av den uppmätta ytan. Denna metod är snabb och okänslig för vibrationer men datapunkterna kan innehålla fel i vissa regioner, vilket hanteras av registreringen. Ett inversproblem som uppkommer i många optiska formmätningsmetoder är fasuppvikning. Vi introducerar en uppvikningsmetod med regularisering genom att använda information från ett CAD-objekt. Formmätningsmetoden som vi använder oss av här baserar sig på två-våglängds holografi. Vår fasuppvikningsmetod funkar oberoende av diskoninuiteter men mätobjektet får inte avvika alltför mycket i form jämfört med CAD-objektet. En metod för att snabbt få fram den behövda forminformationen från CAD-objektet är också utvecklad. För att få fram lämplig forminformation från datapunkter kan en parametrisk kurva eller yta, t.ex. NURBS, anpassas till dessa punkter. Ett delproblem som uppstår vid NURBS-anpassning vid användandet av Gauss-Newton metoden är studerad. Beräkningsaspekter för att få fram en sökriktning är diskuterade. Vi behandlar också metoder för NURBS anpassning som baserar sig på en teknik för separabla icke-linjära minstakvadratproblem. Denna teknik använder sig av variabelprojektioner för att separera beräkningarna av de linjära parametrarna från beräkningarna av de icke-linjära parametrarna. / Godkänd; 2011; Bibliografisk uppgift: Sammanläggningsavhandling bestående av sju artiklar och en tillhörande kappa.; 20110509 (berper); DISPUTATION Ämnesområde: Teknisk-vetenskapliga beräkningar/Scientific Computing Opponent: Professor Mårten Gulliksson, Institutionen för naturvetenskap, teknik och matematik, Mittuniversitetet, Sundsvall Ordförande: Docent Inge Söderkvist, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet, Luleå Tid: Tisdag den 27 september 2011, kl 10.30 Plats: D2214-15, Luleå tekniska universitet

<p>Emhart Glass is the world’s leading manufacturer of equipment, controls and components to the glass container industry. The goal of this project has been to identify improvements and propose cost saving solutions when moving one of Emhart Glass work cells in Sundsvall. The changes shall result in improved work environment and increased product quality. The method contains value stream mapping, concept selection and P-FMEA and complies with Emhart Glass goal to become a more Lean focused business. The way of working with Lean Production is to systematically decrease waste and focus on value added activities. The improvements in the work environment areas consider physical, ergonomic and psychosocial aspects. Concepts for supply of material and assembly process were created from the results of the observation study and the value steam mapping. After evaluation of the concepts, kitting and assembly with one piece flow appears to be the most qualified concepts. Kitting and one piece flow leads to increased quality, improved work environment and reduced cycle time. Results from tests made with prototypes of assembly pallets gave valuable insights that helped refining the concepts. A risk analysis was made in form of aP-FMEA and it showed a critical failure mode that required action. Kitting was identified as a possible action to the critical failure mode, which strengthens the concept of kitting as a preferred method. The project also resulted in a layout which improves the work environment and renders the possibility of one piece flow assembly. In order to meet future requirements with decreased cycle times, Emhart Glass isrecommended to standardize kitting in pallets for all their work cells and develop their internal transport system with a time based truck transport process.</p> / <p>Emhart Glass är världsledande inom tillverkning av utrustning, kontrollsystem och delar till glasindustrin. I Sundsvall sker montering av glasformningsmaskiner och mekanismer. Målet med projektet har varit att i samband med flytt av en av Emhart Glass montageceller identifiera förbättrings­möjligheter och ge förslag till kostnads­besparande lösningar som leder till bättre arbetsmiljö och högre kvalitet. Metoden har följt Emhart Glass arbete mot en mer Lean-inriktad verksamhet och innehåller verktyg som värdeflödes­analys, konceptval och P-FMEA. Lean Produktion kan översättas till smal eller resurssnål produktion och syftar till att systematiskt minska slöseri samt sätta fokus på de värdeskapande aktiviteterna. Arbetsmiljömässigt behandlar rapporten de fysikaliska, ergonomiska och psykosociala aspekterna. Utifrån resultatet av observationsstudien och värdeflödesanalysen skapades koncept för materialförsörjning och montering. Att kitta materialet till cellen och montera i enstycksflöde var de koncept som efter utvärdering framstod som kvalificerade lösningar. Kittning och enstycksflöde leder bland annat till högre kvalitet, bättre arbetsmiljö och reducerad genomloppstid. Test genomfördes med prototyper till montagepaletter vilket resulterade i fler värdefulla insikter. En riskanalys i form av en P-FMEA genomfördes på material­försörjnings­processen. Felorsakerna talade ytterligare för att kittning är en bra lösning eftersom det är en process som kan appliceras som åtgärd till kritiska felsätt. Projektet har också lett fram till en layout där flödesmontering möjliggörs och en process där det termiska klimatet, ergonomin och montörernas egenkontroll i arbetet förbättras. För att möta framtidens krav med kortare genomloppstider ges förslag till att standardisera kittning i paletter för samtliga montage och bygga ut de interna trucktransporterna med ett taktat system för hämtning och avlämning av gods.</p>

Emhart Glass is the world’s leading manufacturer of equipment, controls and components to the glass container industry. The goal of this project has been to identify improvements and propose cost saving solutions when moving one of Emhart Glass work cells in Sundsvall. The changes shall result in improved work environment and increased product quality. The method contains value stream mapping, concept selection and P-FMEA and complies with Emhart Glass goal to become a more Lean focused business. The way of working with Lean Production is to systematically decrease waste and focus on value added activities. The improvements in the work environment areas consider physical, ergonomic and psychosocial aspects. Concepts for supply of material and assembly process were created from the results of the observation study and the value steam mapping. After evaluation of the concepts, kitting and assembly with one piece flow appears to be the most qualified concepts. Kitting and one piece flow leads to increased quality, improved work environment and reduced cycle time. Results from tests made with prototypes of assembly pallets gave valuable insights that helped refining the concepts. A risk analysis was made in form of aP-FMEA and it showed a critical failure mode that required action. Kitting was identified as a possible action to the critical failure mode, which strengthens the concept of kitting as a preferred method. The project also resulted in a layout which improves the work environment and renders the possibility of one piece flow assembly. In order to meet future requirements with decreased cycle times, Emhart Glass isrecommended to standardize kitting in pallets for all their work cells and develop their internal transport system with a time based truck transport process. / Emhart Glass är världsledande inom tillverkning av utrustning, kontrollsystem och delar till glasindustrin. I Sundsvall sker montering av glasformningsmaskiner och mekanismer. Målet med projektet har varit att i samband med flytt av en av Emhart Glass montageceller identifiera förbättrings­möjligheter och ge förslag till kostnads­besparande lösningar som leder till bättre arbetsmiljö och högre kvalitet. Metoden har följt Emhart Glass arbete mot en mer Lean-inriktad verksamhet och innehåller verktyg som värdeflödes­analys, konceptval och P-FMEA. Lean Produktion kan översättas till smal eller resurssnål produktion och syftar till att systematiskt minska slöseri samt sätta fokus på de värdeskapande aktiviteterna. Arbetsmiljömässigt behandlar rapporten de fysikaliska, ergonomiska och psykosociala aspekterna. Utifrån resultatet av observationsstudien och värdeflödesanalysen skapades koncept för materialförsörjning och montering. Att kitta materialet till cellen och montera i enstycksflöde var de koncept som efter utvärdering framstod som kvalificerade lösningar. Kittning och enstycksflöde leder bland annat till högre kvalitet, bättre arbetsmiljö och reducerad genomloppstid. Test genomfördes med prototyper till montagepaletter vilket resulterade i fler värdefulla insikter. En riskanalys i form av en P-FMEA genomfördes på material­försörjnings­processen. Felorsakerna talade ytterligare för att kittning är en bra lösning eftersom det är en process som kan appliceras som åtgärd till kritiska felsätt. Projektet har också lett fram till en layout där flödesmontering möjliggörs och en process där det termiska klimatet, ergonomin och montörernas egenkontroll i arbetet förbättras. För att möta framtidens krav med kortare genomloppstider ges förslag till att standardisera kittning i paletter för samtliga montage och bygga ut de interna trucktransporterna med ett taktat system för hämtning och avlämning av gods.

In product manufacturing, assembly approximately represents 50% of the total work hours. Therefore, an efficient and fast assembly system is crucial to get competitive advantages at the global market and have the right product quality. Today, the verification of the assembly system is mostly done by utilizing software based simulation tools even though limitations have been identified. The purpose of this thesis is to identify when the use of additive manufacturing technology could be used in assessing the feasibility of the assembly system design. The research questions were threefold. First, identifying limitations that are connected with the used assembly simulation tools. Secondly, to investigate when additive manufacturing can act as a complement to these assembly simulations. Finally, to develop a framework that will assist the decision makers when to use additive manufacturing as a complement to assembly simulations. The researchers used the method of case study combined with a literature review. The case study collected data from semi-structured interviews, which formed the major portion of the empirical findings. Observations in a final assembly line and the additive manufacturing workshop provided valuable insights into the complexity of assembly systems and additive manufacturing technologies. In addition, document studies of the used visualization software at the case company resulted in an enhanced understanding of the current setting. The case study findings validate the limitations with assembly simulations described in theory. The most frequent ones are related to visibility, positioning, forces needed for the assembly operator, and accessibility between different parts. As both theory and case study findings are consistent in this respect, simulation engineers should be conscious of when to find other methods than simulation for designing the assembly system. One such alternative method is the utilization of additive manufacturing. The thesis outlines a number of situations where additive manufacturing indeed could act as a complement to assembly simulation. The authors argue that the results and findings to a large degree are applicable to other industries as the automotive sector is very global and competitive in nature and encompasses a large variety of complex assembly operations. A structured framework was also developed that could act as a decision support. The framework takes into account three dimensions that are crucial for the decision; (1) the assembly simulation limitation, (2) the context of the assembly and which parts are involved and (3) the possible limitations of additive manufacturing in the specific context. This impartial decision framework could help companies with complex assembly systems to know when to use additive manufacturing, as well as for which parts and subparts additive manufacturing is applicable. To increase the longevity of the decision framework, new improvements of assembly simulation tools and additive manufacturing technologies, respectively, should be incorporated in the framework.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / As we adopt and implement the doctrines of reengineering, we at NASA/Jet Propulsion Laboratory (JPL) are asked to make a giant leap in how we think of and design SpaceCraft. We call what we are doing a revolution, since we are not “evolving” to the next step in our activity, but literally leaping beyond it. This is fully in concert with the concepts of reengineering, in that areas that need to be changed are indeed literally invented anew. To be successful, JPL and its industry partners, must perfect processes, techniques and methods that allow them to work together at all levels of the SpaceCraft development cycle. If all other parts of the discipline have moved on and changed, but a key portion remains locked in a time warp of yesterday, we will not be able to reach our desired goal. At the present time change is occurring all over JPL, and it is our intent to describe how it applies to areas where prototype, or one of a kind hardware are fabricated, and how these areas might look when new approaches to doing business are applied. Since all activities in an organization must attain similar levels of expertise or be in danger of hampering the entire process, the issues of Packaging Engineering, Manufactureability, and fabrication become key items.

<p>This thesis is based on the present needs for the factory planning support, of which the most important ones are:</p><p>• A structured reuse of knowledge and support for industries. Because today the industry handbook in factory planning is not satisfying enough to support this complex process.</p><p>• Better methods to represent and communicate data between software within the factory layout area for easier data communication and thereby information access, exchange and reuse.</p><p>To support the factory planning, based on the mentioned needs, a mapping of the present factory planning process is made based on knowledge from industry and academy. Since the factory planning process is a huge and complex process that no one can handle by themself, a puzzle work is performed. Based on gathered information and knowledge an activity model is developed, to structure the data and information. The model gives a better overview on the actual course of events and in this way also “captures” the most important information to be represented for data exchange among different software applications and different people.</p><p>In this thesis the most important information in factory layout is gathered and structured in a concept model for factory layout. Since the concepts depend on the context in which they are used, it is extremely important to present every concept in its relationship with other related concepts within the area.  A general theory and state-of-the-art definitions in the area is presented and discussed for a factory planning information management system. An evaluation and discussion is made for the state-of-the-art software in the area of concern.</p>