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  • 151.
    Chibba, Aron
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK).
    Rundquist, Jonas
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK).
    Förbättring av produktinnovationsprocesser inom ramen för TQM2001In: Forskningssamverkan och nya former av kunskapsbildning: sammanställning av bidrag till konferensen Högskolor och samhälle i samverkan, Högskolan i Halmstad, 9-11 maj 2001 : proceedings from the 2nd HSS Research Conference, Halmstad University, Sweden, May 9-11, 2001 / [ed] Kjell Eriksson, Halmstad: Högskolan i Halmstad , 2001, p. 249-258Conference paper (Other (popular science, discussion, etc.))
    Abstract [sv]

    Forskning inom management och organisation indikerar att innovativa företag är dubbelt så lönsamma som andra företag (Tidd et. al., 1997). Innovationsverksamhet är riskabel och svår att organisera, men sedan 1980-talet har ett flertal modeller presenterats för att organisera innovationsverksamhet. Forskningen inom detta område benämns ibland Innovation management. TQM-konceptet är en managementfilosofi för att förbättra den operationella kvaliten i ett företag och som baseras på de anställdas deltagande, ständiga förbättringar och kundtillfredsställelse.

    I denna artikel kommer vi att försöka skapa grunden till en kombinerad modell för TQM och innovationsledning som drar nytta av de båda filosofiernas respektive styrkor. Vi kommer också att diskutera hur modellen kan användas och vidareutvecklas av små och medelstora företag i samarbete med högskolan.

  • 152.
    Christian, sandberg
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Hansson, Måns
    The Sally: Ett mekaniskt vattenreningssytem2019Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
  • 153.
    Christiansson, Eric
    et al.
    Halmstad University, School of Business and Engineering (SET). CAD-Tekniker.
    Moretti, David
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK). CAD-Tekniker.
    Kinematics methodology and simulation in Catia v52013Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 154.
    Connolly, David
    et al.
    Aalborg University, Aalborg, Denmark.
    Mathiesen, Brian Vad
    Aalborg University, Aalborg, Denmark.
    Østergaard, Poul Alberg
    Aalborg University, Aalborg, Denmark.
    Möller, Bernd
    Aalborg University, Aalborg, Denmark.
    Nielsen, Steffen
    Aalborg University, Aalborg, Denmark.
    Lund, Henrik
    Aalborg University, Aalborg, Denmark.
    Persson, Urban
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Nilsson, Daniel
    Halmstad University, School of Business, Engineering and Science.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Trier, Daniel
    PlanEnergi, Copenhagen, Denmark.
    Heat Roadmap Europe 2050: First Pre-study for the EU272012Report (Other academic)
    Abstract [en]

    This pre-study presents the findings concerning a considerable outlined expansion of the district heating sector within the current EU27 member states until 2050. Heat deliveries are presumed to grow by a factor of 2.1 until 2030 and by a factor of 3.3 until 2050.

    The current energy policy context is that the latest energy communication from the European Commission (Energy Roadmap 2050) contains only a very modest growth in the future for district heating systems and additional industrial heat use from industrial CHP plants. A small increase is foreseen for industrial demands, while heat deliveries to the residential and service sectors are expected to decrease. In total, the heat delivered is expected to increase by less than one per cent per year, giving a total increase of 20% until 2030 and of 40% until 2050.

    In this prestudy, more ambitious growth rates are assessed for district heating in the EU27 between 2010 and 2050. The chosen methodology in this pre-study contains a combination of hour-by-hour energy modelling of the EU27 energy system and mapping of local conditions, which is essential for district heating analysis. However, the link between these two actions has not been fully utilised in this pre-study due to the limited working time available: The mapping action has only indicated the input to the energy modelling action.

  • 155.
    Connolly, David
    et al.
    Aalborg University, Aalborg, Denmark.
    Mathiesen, Brian Vad
    Aalborg University, Aalborg, Denmark.
    Østergaard, Poul Alberg
    Aalborg University, Aalborg, Denmark.
    Möller, Bernd
    Aalborg University, Aalborg, Denmark.
    Nielsen, Steffen
    Aalborg University, Aalborg, Denmark.
    Lund, Henrik
    Aalborg University, Aalborg, Denmark.
    Persson, Urban
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Grözinger, Jan
    Ecofys Germany GmbH, Cologne, Germany.
    Boermans, Thomas
    Ecofys Germany GmbH, Cologne, Germany.
    Bosquet, Michelle
    Ecofys Germany GmbH, Cologne, Germany.
    Trier, Daniel
    PlanEnergi, Copenhagen, Denmark.
    Heat Roadmap Europe 2050: Second Pre-study for the EU272013Report (Other academic)
    Abstract [en]

    Many strategies have already been proposed for the decarbonisation of the EU energy system by the year 2050. These typically focus on the expansion of renewable energy in the electricity sector and subsequently, electrifying both the heat and transport sectors as much as possible. In these strategies, the role of district heating has never been fully explored system, nor have the benefits of district heating been quantified at the EU level. This study combines the mapping of local heat demands and local heat supplies across the EU27. Using this local knowledge, new district heating potentials are identified and then, the EU27 energy system is modelled to investigate the impact of district heating. The results indicate that a combination of heat savings, district heating in urban areas, and individual heat pumps in rural areas will enable the EU27 to reach its greenhouse gas emission targets by 2050, but at a cheaper price than a scenario which focuses primarily on the implementation of heat savings.

  • 156.
    Cyrén, Oscar
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Harryson, Moa
    Halmstad University, School of Business, Engineering and Science.
    Development of Methods and Guidelines for Upper Extremity Injury in Car Accidents2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project focus has been development of guidelines and methods for upper

    extremity injury reduction in car crashes. The safety of the central body parts

    improves which indicates the need to develop methods for avoiding non-life

    threatening injuries such as fracture of the arms. The purpose of the project was to

    study the injury mechanisms for the upper extremity in car crashes, and the aim has

    been to propose methods to reduce the injuries. The project focuses on adult

    occupants inside the vehicles front seat, and frontal and side impacts. The procedure

    began with understanding and identifying the injury mechanisms. Studies show that

    most fractures occur on the forearm (radius and ulna) and on the wrists and hands.

    To determine which injury mechanisms that were most frequent, data were collected

    from 29 computer simulations with 29 different crash scenarios. The most common

    kind of impact was the medial part of the wrist in the central part of the instrument

    panel, combined with the impact of the elbow in the center consol. The results of the

    simulations created a basis for the method of the component test, with focus on the

    injury mechanism i.e. the forward movement of the arms into the instrument panel.

    The component test consisted of a test rig, on which was mounted with a measuring

    arm of a 50th percentile male dummy. The arm dropped into a block of expanded

    polypropylene (EPP-block) for observation and study, and with following variable

    parameters: the impact angle of the surface, velocity and position of the wrist. Then

    also an instrumented measuring arm from a 5th percentile female dummy was

    released into an instrument panel.

    The project contributes to knowledge about the injury mechanism of the upper

    extremity in car crashes. The most frequent injury mechanism is a forward movement

    of the arms resulting in an impact with the interior structure of the car. The most

    frequent injured region is the distal part of the upper extremity. The project has

    developed and suggested the first step to a test method for the specific injury

    mechanism. There is a need of more research on how impact angles and velocity

    affect the violence on the arm.

  • 157.
    Cámara Ortiz, Héctor Miguel
    Halmstad University.
    Filling quality control and redesign of small scale bottling machine for carbonated beverages2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The current design of the machine presents efficiency and performance problems,mainly due to over-foaming and lack of accurate fill level controls. A flowdynamics analysis was done with the intention of understanding the factorscontrolling the foam formation and propose improvements that will directly impactthe machine´s KPI´s.

    As result of the analysis the change from counter pressure to atmospheric filling isproposed as well as the re-programing of its PLC together with physical changes tothe flow path, and the use of a better suited speed controlling device.

    The proposed fill speed controlling device was analyzed with the aid ofcomputational fluid dynamics software and then quantitatively characterized. Allthe proposed changes suggest a possible change in speed from 3 bottles per minuteto above 8.5 bottles per minute with minimum intervention to the machine.

  • 158.
    Dahlborg, Gustav
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Andersson, Niklas
    Halmstad University, School of Business and Engineering (SET).
    MC - Trailer Leloup2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We got in touch with a company in Halmstad with a history of having theises inconnection with the mechanical engineering programs at Halmstad University. Asa response to the availability to a thesis we got a proposal to develop an earlierthesis that the company has had with them. Upon further investigation of thethesis, we decided with the company that a full trailer would be constructed. Ourreport includes our steps to develop a concept design of a trailer. All the essentialsteps we have taken are described in the report, from the conceptual stage to thepoint where you’re able to produce a prototype. We started with the regulationsand standards that exist in the subject, these are closer mentioned in the report.The result of the thesis is a concept design for a trailer, we do believe there isopportunity for further growth, especially through the development of a prototype

  • 159.
    Dahlqvist, Alfred
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Johansson, David
    Halmstad University, School of Business and Engineering (SET).
    Gummiupprullare2013Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This report is a 7.5hp thesis at the CAD-technicians programme at Halmstad University.

    The group has been asked by the company National Gummi AB in Trönninge to develop a winder for large rubber profiles. Employees roll down rubber profiles in a pallet by hand which can wear out employees backs due to the weight of the rubber profiles.

  • 160.
    Dahlqvist, Alfred
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK).
    Johansson, David
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK).
    Konstruktion av trehjulig elcykel2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har gjorts i samarbete med företaget Off Course AB, som är beläget i Halmstad, och har gått ut på att tillverka en trehjulig elcykel som är stabil nog att stanna utan att sätta ner fötterna.

    Det är framförallt medelålders och äldre personer som använder en elcykel och ersätter såväl bilresor som kollektivtrafiken. En cykel med tramp- eller vevanordning och elassistans, som inte ger krafttillskott vid hastigheter över 25km/h, räknas som en elcykel. Under projektets början undersöktes de lagar och restriktioner som finns samt hur andra trehjuliga cyklar är konstruerade. En viktig punkt för cykeln är att den ska vara stabil och kunna stå utan något sorts stöd. Författarna har även inspirerats av andra fordon som kan stå utan hjälp och fortfarande ha en bra körupplevelse. Exempel på produkter som undersökts är flakmopeder, trehjuliga motorcyklar samt gokarts.

    När idéförslagen sållats ner till två, valde författarna att tillverka prototyper av dessa för att testa körupplevelsen då det är en viktig faktor. Slutgiltiga lösningen var att använda sig av Ackermanns styrgeometri som även är integrerade på bilar och gokarts.

  • 161.
    Dalla Rosa, Alessandro
    et al.
    Technical University of Denmark, Lyngby, Denmark.
    Li, Hongwei
    Technical University of Denmark, Lyngby, Denmark.
    Svendsen, Svend
    Technical University of Denmark, Lyngby, Denmark.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Persson, Urban
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Rühling, Karin
    Dresden University of Technology, Dresden, Germany.
    Felsmann, Clemens
    Dresden University of Technology, Dresden, Germany.
    Crane, Martin
    Scottish & Southern Energy, Perthshire, United Kingdom.
    Burzynski, Robert
    Scottish & Southern Energy, Perthshire, United Kingdom.
    Bevilacqua, Ciro
    Building Research Establishment, Watford, United Kingdom.
    Annex X Final report: Toward 4th Generation District Heating: Experience and Potential of Low-Temperature District Heating2014Report (Other academic)
    Abstract [en]

    Background and Objective

    The evolution of district heating (DH) has gone through three generations since the first introduction of distirct heating. It is characterized by the type of transport media and the network temperature levels: the 1st generation DH system is steam-based system, the 2nd generation DH uses high network supply temperature above 100oC, and the 3rd generation DH represents the current DH system with medium network supply temperature between 80oC to 100oC. Up until now, the 4th generation DH as the low-temperature district heating (LTDH) is emerging as a new system which is going to replace the existing 3rd generation DH system. Comparing with the existing DH system, the LTDH reduces the network supply temperature down to consumer required temperature level, thus greatly improves the quality match between the energy supply and the energy demand. Meanwhile, LTDH coupling with reduced network temperature and well-designed DH network can reduce network heat loss by up to 75% comparing with the current system. This makes DH economically competitive comparing with local heat generation units in the areas with low heat density or with low-energy buildings.

    The traditional approach to evaluating a DH system often focuses on the production/supply aspect and only afterwards on the final users. The LTDH concept switches the perspective, starting from end-user thermal comfort and a quality match between energy supply and energy consumption, and aiming to find the best and most economical way to satisfy the heat demand through efficient distribution networks and supply systems based on waste heat and RE. The new concept therefore starts by identifying suitable in-house substations for low-energy-demand buildings at low supply temperature, goes back to design efficient and reliable networks, and finally considers environmentally-friendly heat production units.

    This report describes the concept of LTDH, collects and discusses successful examples of implementation LTDH in the building heating sector. The objective of this report is to raise awareness and provide insights that will stimulate the research, development and implementation of LTDH systems. It will help to increase public recognition and assist policy makers and energy planners, both at local and governmental level, in promoting cost-effective and environmentally friendly DH systems, and in planning and realizing long-term sustainable urban area development. To this end, the report addresses the following research issues:

    1. What are the main advantages of LTDH?

    2. What technology options are available for LTDH, and what are the associated challenges to consider?

    3. How can the risk of Legionella be mitigated in LTDH?

    4. What lessons can be learned from early LTDH projects?

    5. What heat distribution costs are associated with LTDH?

  • 162.
    D'Ambrosio, Marco
    et al.
    Halmstad University, School of Business and Engineering (SET). Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Medaglia, Marco
    Halmstad University, School of Business and Engineering (SET). Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Vertical Axis Wind Turbines: History, Technology and Applications2010Independent thesis Advanced level (degree of Master (Two Years)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    In  this  Master Thesis  a  review  of  different  type  of  vertical  axis  wind turbines (VAWT)  and  a preliminary investigation of a new kind of VAWT are presented.

    After an introduction about the historical background of wind power, the report deals with a more accurate analysis of the main type of VAWT, showing their characteristics and their operations. The aerodynamics of the wind turbines and a review of different type on generators that can be used to connect the wind mill to the electricity grid are reported as well.

    Several statistics are also presented, in order to explain how the importance of the wind energy has grown  up  during  the  last  decades  and  also  to  show  that  this development  of  the  market  of  wind power  creates  new  opportunity  also  for VAWT,  that  are  less  used  than  the  horizontal  axis  wind turbine (HAWT).

    In the end of 2009 a new kind of vertical axis wind turbine, a giromill 3 blades type, has been built in Falkenberg, by the Swedish company VerticalWind. The tower of this wind turbine is made by wood,  in  order  to  get  a  cheaper  and  more environment  friendly  structure,  and  a  direct  driven synchronous multipole with permanent magnents generator is located at its bottom. This 200 kW VAWT represents the intermediate step between the 12 kW prototype, built in collaboration with the Uppsala University, and the common Swedish commercial size of 2 MW, which is the goal of the company.

    A  preliminary  investigation  of  the  characteristics  of  this  VAWT  has  been done, focusing  in particular on the value of the frequency of resonance of the tower, an important value that must be never reached during the operative phase in order to avoid serious damage to all the structure, and on the power curve, used to evaluate the coefficient of power (Cp) of the turbine. The results of this investigation and  the steps  followed  to  get  them  are  reported.  Moreover  a  energy production analysis of the turbine has been done using WindPro, as well as a comparison with and older type on commercial VAWT.

  • 163.
    David, Andrei
    et al.
    Aalborg Univ, Dept Planning, Copenhagen, Denmark.
    Vad Mathiesen, Brian
    Aalborg Univ, Dept Planning, Copenhagen, Denmark.
    Averfalk, Helge
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lund, Henrik
    Aalborg Univ, Dept Planning, Aalborg, Denmark.
    Heat Roadmap Europe: Large-Scale Electric Heat Pumps in District Heating Systems2017In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 10, no 4, article id 578Article in journal (Refereed)
    Abstract [en]

    The Heat Roadmap Europe (HRE) studies estimated a potential increase of the district heating (DH) share to 50% of the entire heat demand by 2050, with approximately 25–30% of it being supplied using large-scale electric heat pumps. This study builds on this potential and aims to document that such developments can begin now with technologies currently available. We present a database and the status of the technology and its ability of expansion to other European locations by reviewing experiences aimed at further research or application in the heating industry. This is based on a survey of the existing capacity of electric large-scale heat pumps with more than 1 MW thermal output, operating in European DH systems. The survey is the first database of its kind containing the technical characteristics of these heat pumps, and provides the basis for the analysis of this paper. By quantifying the heat sources, refrigerants, efficiency and types of operation of 149 units with 1580 MW of thermal output, the study further uses this data to analyze if the deployment of this technology on a large-scale is possible in other locations in Europe. It finally demonstrates that the technical level of the existing heat pumps is mature enough to make them suitable for replication in other locations in Europe.

  • 164.
    de Beer, Rocco
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Fredriksson, Jakob
    Halmstad University, School of Business and Engineering (SET).
    Analys och kontroll av hållfasthet på grenställsarm2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis was done in collaboration with EAB situated in Smålandsstenar. In the initial discussion faze on doing a thesis with them there was a need to analyze and ensure the strength of an existing product, cantilever racks. This included performing FEM calculations on a model and comparing the results with physical tests.

    EAB has two models of cantilever racks, a light duty and a heavy duty. Within the heavy duty model series there are five product variants that differ in both size and load capacity. We will be working with the product variant with a load capacity of 1000 kg/arm which is the variant that is in the middle of the series.

    When we started work on the thesis we did a literature study and couldn’t find any well defined methodology that integrates both product development and computer aided design analysis. This meant that we had to combine and use both Freddy Olsson’s principle product development and known methods in FEM analysis.

    In the early stages of our work we also came to the conclusion that we need to compare our FEM analysis results to more than solely normal hand calculations, as these take into account many safety factor that will not be included in our computer aided model. So together with EAB we agreed to perform physical tests that will be similar in setup as our FEM analysis, leading to more comparable results.

    FEM analysis was conducted in CATIA V5 Generative Structural Analysis and physical tests were carried out at EAB in their test facility

  • 165.
    Despotovski, Natali
    et al.
    Halmstad University.
    Vuletic, Sonja
    Halmstad University.
    A Product Development of Safety Car Seats for Children2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Car accidents happens daily, and it is very important to protect all involved in a carno matter the age. Persons that are old enough and can take care of themselves, usescar seat belts to be protected in traffic. A child, however, must be placed andfastened in a safety seat by a parent or another caregiver, to be fully protected. Children that are correctly secured in safety seats have a 2.7 times bigger chance tosurvive a car crash without serious injuries compared to unstrained children (Berget al., 2000; WHO,2004). Regardless tests and safety seats that are available ontoday’s market, there are still issues that needs to be eliminated. Daily users of thisproduct are a good starting point since these people want a safe seat for their childthat can be easy to install and affordable; and they can best tell what issues theyencounter.

    Based on several scientific articles in a combination with interviews andobservations, issues with the safety seats could be confirmed. The primary issue isthe seat belt that is attached to the safety seat. Children can develop a habit ofwriggling out of the belt in safety seats. There are belt collectors available on themarket which holds the shoulder belts in place. In this way, it is harder for thechildren to slide out of the belt and helps to keep the belt properly positioned(BeSafe, 2018). Instead of having this as an accessory, it has been considered in thebelt that have been developed. Another issue is that the belt is complicated tofastened since two straps has to be simultaneously clicked in the belt buckle. If thisis done incorrectly, the belt cannot be fastened, and it takes time to try it again. Tomake this easier, two straps and the strap between the child's leg will be fastenedseparately in a seat buckle each. In this way, parents and other caregivers will beable to fasten the belt easy and properly. They will also be sure that the child issafely fastened and will minimize injury during an accident or another situation.

  • 166.
    Deutschmann, Oliver
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Johansson, Thomas
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Framtidens elbilar utmanar nutidens elnät: Påverkan av ett ökat antal elbilar på ett halländskt elnät2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The challenges facing low voltage grids are rising as an increasing number of domestic houses transition from fossil fueled heating to electricity based heating. Several environmental goals and visions have the same transition from fossil based power to electricity based power in mind for the transportation sector. One of the most important tools for this transformation is widely regarded to be the electric vehicle. With the demands of the electric vehicle pressuring the power grid, several questions arise regarding the growth of the electric vehicle market and what repercussions it may have on the grid. This paper focuses on a typical low voltage grid in southern Sweden and what effects a growing electric vehicle market may have on it. Through computer-assisted simulations based on several future scenarios regarding the EV market, this paper finds that few modifications and reinforcements are needed on this particular grid within the next 10 to 15 years. After this timeframe the voltage drop becomes a serious concern and should be addressed.

  • 167.
    Dia, Ali
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Bengtsson, Fredrik
    Halmstad University, School of Business and Engineering (SET).
    Energikartläggning av lagerbyggnad: en kvalitativ studie mot lagerbyggnader inom logistik branschen2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 168.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterization of Engineering Surfaces Having Linear Features2012In: Proceedings of the 2nd Seminar on Surface Metrology for the Americas, Worcester: Worcester Polytechnic Institute , 2012Conference paper (Refereed)
    Abstract [en]

    There is a variety of engineering surfaces having linear scratches/grooves of different density, width and depth, some parts covered by folded metal, and some parts totally interrupted and unbalanced as a result of the machining or wear process. These grooves are critical for good function of the surface, and need to be quickly and objectively quantified for an efficient surface finish development. A suitable way to do this is to use optical 3D measurements and to combine the profile and image analysis. In this tutorial extraction and quantification of grooves/wear scratches of machined (honed and polished) and worn (honed) surfaces will be presented. In particular, it will be shown how the features, such as width, height, and distance between grooves, honing angle, balance of honing texture, and groove interrupts can be successively characterized.

  • 169.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Optimization of the Triboconditioning Process for Low Friction Surfaces2015Conference paper (Refereed)
  • 170.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Process Optimization of Low Friction Surfaces in Pin-Roller Contacts2014Conference paper (Refereed)
  • 171.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Recent R&D on Engine Cylinders2013Conference paper (Other (popular science, discussion, etc.))
  • 172.
    Dimkovski, Zlate
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Reduced engine friction for low climate impact2014Conference paper (Refereed)
    Abstract [en]

    Reducing friction in the Piston-Cylinder Unit - PCU is one of the priorities in the automotive industry as it is the largest contributor to the frictional losses and hence the fuel consumption of the internal combustion engines. Not only fuel consumption, but also the oil consumption and emissions are largely affected by the piston-ring-liner interactions. Therefore, from an optimized PCU, competitive, economic and environmental benefits would be gained.  In this project, fuel/oil consumption and emissions of car and truck engines were reduced by using different cylinder liner finishes and different ring designs/loads. Experimental and theoretical studies have been performed by simulating and testing the behaviour of various oil control rings and cylinder liner surfaces in reciprocating tribotesters. Several full-scale engine tests were performed to verify the improvements. The engine tests showed up to 1.8% reduction of the fuel consumption while keeping low oil consumption by using smoothly honed liner surfaces and low ring loads/widths. Further reduction of the oil consumption was shown in the tribotests and simulations when textured liner surfaces were used. To accomplish this, a cost-effective texturing process has to be found and to be confirmed in the engine tests.

  • 173.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Anderberg, Cecilia
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Powertrain Corp., Volvo Group, Göteborg, Sweden.
    Rosén, Bengt - Göran
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterisation of worn cylinder liner surfaces by segmentation of honing and wear scratches2011In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 271, p. 548-552Article in journal (Refereed)
    Abstract [en]

    The presence of the honing scratches/grooves in cylinder liner surfaces is intended and desired as they improve the lubrication and retain the debris reducing the piston assembly/liner friction and consequently improve the fuel economy and longevity of the internal combustion (IC) engines. Axial scratches caused by the abrasive wear between the tribological partners and/or entrained wear particles are undesired since they are correlated with increased oil consumption and noxious emissions of the IC engines. Due to the imperfection of the manufacturing process, the honing grooves, especially the deep ones, are smeared and interrupted by folds. A portion of the folds would eventually detach during the running process and act as abrasive particles increasing the wear in the cylinder. To closely examine the influence of all these features on the liner's function, it emerges a need to objectively quantify the axial wear scratches, plateau honing grooves, deep honing grooves and their interrupts. The existing techniques fail to segment a groove containing interrupts as they usually appear as summits at several locations in the course of the groove. Combining the profile and image analyses, the deep grooves and their interrupts were successfully identified and quantified in earlier works of the authors. In this paper those algorithms are extended, so that the deep honing grooves, plateau honing grooves and axial scratches crossing different depth levels are sequentially segmented in three levels/steps in an immersing way. A number of parameters derived from this method were utilised to compare 3D interference measurements from the top dead centre, middle and bottom region of a liner run in a truck engine test whereas the three regions represent different wear regimes due to the different running conditions. The results show that: (i) the axial scratches are densest in the top dead centre and about the same size as the plateau grooves in all three regions, while in the bottom region there are only few scratches; (ii) the presence of plateau grooves in the top region clearly decreases, (iii) the deep groove interrupt and coverage are lowest in the top region, and (iv) the groove height and distance between grooves spread mostly.

  • 174.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Anderberg, Cecilia
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK). Volvo Cars Corp. Base Engine Department Gothenburg, Halmstad, Sweden.
    Ohlsson, Robert
    Volvo Power Train Corp, Volvo Group Gothenburg, Halmstad, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterisation of Cylinder Liner Honing Textures for Production Control2013In: Characterisation of Areal Surface Texture / [ed] Richard Leech, Berlin: Springer Berlin/Heidelberg, 2013, p. 281-302Chapter in book (Refereed)
    Abstract [en]

    It is of common interest to reduce oil consumption and frictional losses in internal combustion engines, which are heavily influenced by the quality of the cylinder liner surface. The plateau cross-hatch topography of a cylinder liner consists of a system of grooves of different density, width and depth, some parts covered by folded metal, and some parts totally interrupted and unbalanced as a result of imperfection in the honing process. These grooves are critical for good liner function, and need to be quickly and objectively quantified for an efficient surface finish development. A suitable way to do this is to use 3D interference measurements and to combine profile and image analysis. Thus, the features/parameters, such as honing angle, balance of honing texture, groove interrupts, width, height, and distance between grooves, are successively quantified. Here, these parameters, along with areal surface texture parameters in the published ISO specification standard were used in two case studies. The first case study is on the effect of the folded metal on the surfaces of run truck liners and the second is an evaluation of the improvements of the surface quality introduced by the diamond honing in production of car liners. In addition, based on the significant parameters of the surface, a general characterisation tool for qualifying the surface quality and determination of the required number of measurements is presented. © 2013 Springer-Verlag Berlin Heidelberg. All rights are reserved.

  • 175.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Guilbert, Franck
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces. Ecole Nationale Supérieure d'Arts et Métiers, Centre Arts et Métiers ParisTech, Aix en Provence, France.
    Lundmark, Jonas
    Applied Nano Surfaces Sweden AB, Uppsala, Sweden.
    Mohlin, Johan
    Gnutti Carlo Sweden AB, Gothenburg, Sweden.
    Rosén, B.-G.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Optimization of the Triboconditioning Process on External Cylindrical Surfaces2015In: Proceedings of the 15th International Conference on Metrology and Properties of Engineering Surfaces, Raleigh, NC: American Society for Precision Engineering (ASPE) , 2015Conference paper (Refereed)
    Abstract [en]

    The use of tungsten disulfide in tribofilms on functional surfaces has been a proven way to reduce the frictional losses in rolling and sliding contacts, especially in lubricated contacts at boundary and mixed regime. A suitable and cost-effective process to deposit tungsten disulfide is by ANS Triboconditioning, the mechano-chemical surface finishing process for improving the tribological properties of mechanical components made of steel or cast iron. However, it is not known what are the optimal process parameters, speeds and pressures, to achieve an optimal surface treatment. In this paper, the modifications of the work-piece surfaces under Triboconditioning have been tracked to optimize the process parameters. To closely control the conditions, a commercial tribometer with a block-on-ring configuration was used. Cylindrical tungsten carbide samples (representing the tool) were rubbed against steel rings (representing the work-piece) under two different loads and speeds. The ring surfaces of two different finishes (ground and honed) were measured on the same place before and after treatment to track the surface modifications. At last, the treated rings were rubbed against a flat steel surface in start-stop sequences that resemble pin-roller operating conditions of a truck valve train and the friction behavior was screened. The results show a reduction of the core roughness of the ring surfaces with the lowest friction for the ground rings treated by low load and low speed.

  • 176.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Kofod, Guggi
    InMold Biosystems, Farum & Høje-Taastrup, Denmark.
    Rebeggiani, Sabina
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Evaluation of Durability of SOG-layers on Steel Surfaces by Wear and Scratch Tests2014Conference paper (Refereed)
    Abstract [en]

    Steel moulds with high precision surfaces are being used in various branches. Process aspects, like tool life and tribological properties, as well as design issues are of great importance. This work summarises experimental studies performed to test durability properties of SOG (spin-on-glass)-layers on steel surfaces. This coating technique is based on a newly developed method for surface preparation of tools which has been demonstrated to be durable for more than 66.000 replications in injection moulding processes without loss of surface fidelity. The procedure allows surface roughness reduction from approximately 200 nm Ra down to some few nm for high gloss applications, as well as easy transfer of large-area functional nanostructures on complex 3D surfaces.

    Three different types of surfaces were investigated: SOG-layered metal surfaces with three different layer thicknesses, one ingot casted and one electro slag remelted material (with hardness level of 950 and 2500 MPa, respectively). The metal surfaces were ground and polished to mirrorlike finishes.

    Three circular samples of each type were rubbed against a hard steel ball of 6.35 mm radius on a commercial pin-on-disk tribometer. To resemble the molding process a sliding speed of 2 mm/s and a load of 8 N were chosen. The tests were performed with 5 minutes intervals until the first damage on the surface were observed. In parallel, scratch tests were performed in the same tribometer. The surfaces were measured in-situ by a portable microscope and a stylus, and afterwards by a white light interferometer and scanning electron microscope to evaluate the size of the wear/scratch traces.

    The surface type with the longest time to damage and/or smallest wear/scratch traces was considered to be the most durable one.

  • 177.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lööf, Pär-Johan
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Dumbreville, Lucas
    Halmstad University, School of Business, Engineering and Science. École nationale d'ingénieurs de Saint-Étienne (ENISE), Saint-Étienne, France.
    Rosén, Bengt Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Nilsson, Per
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Functional Parameters Screening for Predicting Wear between Two Cylindrical Surfaces with Different Finishes2017In: Mets&Props 2017: 16th International Conference on Metrology and Properties of Engineering Surfaces: Conference abstracts, 2017, p. 75-76Conference paper (Refereed)
  • 178.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Lööf, Pär-Johan
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Rosén, Bengt Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Nilsson, Per
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Functional parameter screening for predicting durability of rolling sliding contacts with different surface finishes2018In: Surface Topography: Metrology and Properties, ISSN 2051-672X, Vol. 6, no 2, article id 024005Article in journal (Refereed)
    Abstract [en]

    The reliability and lifetime of machine elements such as gears and rolling bearings depend on their wear and fatigue resistance. In order to screen the wear and surface damage, three finishing processes: (i) brushing, (ii) manganese phosphating and (iii) shot peening were applied on three disc pairs and long-term tested on a twin-disc tribometer. In this paper, the elastic contact of the disc surfaces (measured after only few revolutions) was simulated and a number of functional and roughness parameters were correlated. The functional parameters consisted of subsurface stresses at different depths and a new parameter called 'pressure spikes' factor'. The new parameter is derived from the pressure distribution and takes into account the proximity and magnitude of the pressure spikes. Strong correlations were found among the pressure spikes' factor and surface peak/height parameters. The orthogonal shear stresses and Von Mises stresses at the shallowest depths under the surface have shown the highest correlations but no good correlations were found when the statistics of the whole stress fields was analyzed. The use of the new parameter offers a fast way to screen the durability of the contacting surfaces operating at similar conditions. © 2018 IOP Publishing Ltd.

  • 179.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Effect of the measurement size on the robustness of the assessment of the features specific for cylinder liner surfaces2014In: Surface Topography: Metrology and Properties, ISSN 2051-672X, Vol. 2, no 1, article id 014013Article in journal (Refereed)
    Abstract [en]

    The quality of the cylinder liner surface is of great importance due to its impact on the fuel/oil consumption and emissions of the internal combustion engine. A good liner function depends on the size and distribution of the deep honing grooves and the amount of the cold work material (Blechmantel) left inside the grooves after finishing. A fast evaluation of these features requires optical three-dimensional measurements with a large area and good resolution, but many interferometers used today have limited resolution when measuring larger areas. To find out how the measurement size and resolution would affect the quantification and the variation of the parameters, two objectives, 2.5 ×  and 10 × , were used for measuring a cylinder liner from a truck engine. The Blechmantel was of special interest as it first comes into contact with piston/rings, detaches as particles and wears the running surfaces. The 2.5 ×  objective showed more robust assessment than the 10 ×  one, manifested by a lower coefficient of variation for the parameters describing the features: Blechmantel, groove width and height, groove balance and number of grooves. This means that fewer measurements are required if a 2.5 ×  objective is used in production and hence the time and cost of the liner would be decreased. © 2014 IOP Publishing Ltd.

  • 180.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Group Trucks Technology, Gothenburg, Sweden.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Effect of the Measurement Size on the Robustness of the Assessment of the Features Specific for Cylinder Liner Surfaces2013In: Metrology and Properties of Engineering Surfaces, 2013: Proceedings of the 14th International Conference on Metrology and Properties of Engineering Surfaces, 2013, p. 377-381Conference paper (Refereed)
    Abstract [en]

    The quality of the cylinder liner surface is of great importance due to the impact on the fuel/oil consumption and emissions of the internal combustion engines. A good liner function depends on the size and distribution of the deep honing grooves and amount of the cold work material (Blechmantel) left inside the grooves after finishing. A fast evaluation of these features requires optical 3D measurements with a larger area and good resolution, but the commercial interferometers used today are with limited resolution when measuring larger areas. To find out how the measurement size and resolution would affect the quantification and number of measurements needed for a robust assessment, two objectives, 2.5x and 10x, were used for measuring a cylinder liner from a truck engine. The Blechmantel was of a special interest as it first comes into a contact with piston/rings, detaches in particles and wears the running surfaces. The 2.5x objective showed more robust assessment than the 10x one manifested with lower number of measurements needed for the parameters describing the features: Blechmantel, groove width and height, groove balance and number of grooves.

  • 181.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Ohlsson, Robert
    Volvo Power Train Corp Sweden.
    Rosén, Stefan
    Toponova AB, Sweden.
    Rosén, B.-G.
    Halmstad University, School of Business and Engineering (SET), Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Characterisation of transparent deposits on cylinder liner surfaces of HDD truck engines2009Conference paper (Refereed)
  • 182.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Tomanik, Eduardo
    MAHLE Metal Leve, Jundiai, Sao Paulo, Brazil; University of Sao Paulo, Sao Paulo, Brazil.
    Grange, Simon
    Halmstad University, School of Business, Engineering and Science. École nationale d'ingénieurs de Saint-Étienne (ENISE), Saint-Étienne, France.
    Epinat, Flavien
    Halmstad University, School of Business, Engineering and Science. École nationale d'ingénieurs de Saint-Étienne (ENISE), Saint-Étienne, France.
    Novel Testing Methods for Screening the Tribological Performance of Ring-Liner Surfaces2017In: Mets&Props 2017: 16th International Conference on Metrology and Properties of Engineering Surfaces: Conference abstracts, 2017, p. 59-60Conference paper (Refereed)
  • 183.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Tomanik, Eduardo
    University of Sao Paulo, Sao Paulo, Brazil.
    Grange, Simon
    Halmstad University, School of Business, Engineering and Science. ENISE, St. Étienne, France.
    Epinat, Flavien
    Halmstad University, School of Business, Engineering and Science. ENISE, St. Étienne, France.
    Novel testing methods for screening the tribological performance of ring-liner surfaces2018In: Surface Topography: Metrology and Properties, E-ISSN 2051-672X, Vol. 6, no 3, article id 034017Article in journal (Refereed)
    Abstract [en]

    The piston system accounts for about the half of the frictional losses of internal combustion engines and requires special testing methods to understand and improve its function. The most common way to screen the surface performance is to rub ring/liner segments against each other in a reciprocating manner. However, short reciprocating tests have intrinsic low sliding speeds, unable to reach the mixed/hydrodynamic regimes found in the engine, especially at the mid-stroke. This paper presents a rotating test for the oil control ring, which has the largest frictional losses of all other rings. Both reciprocating and rotating tests were conducted using different in-house developed modules and fixtures. Twin land oil control rings against liners with two different finishes commonly used in heavy duty diesel truck engines were tested under similar loads and speeds as in a real engine. Engine oil 5W-30 and room temperature was used for all the tests. Sliding speed, load, friction force and electrical resistance were recorded during the tests. The results show a clear discrimination of the different liner finishes depending on the lubrication regime present.

  • 184.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Tomanik, Eduardo
    MAHLE Metal Leve, Jundiai, Sao Paulo, Brazil.
    Profito, Francisco
    University of Sao Paulo, Sao Paulo, Brazil.
    Influence of measurement and filtering type on friction predictions between cylinder liner and oil control ring2016In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 100, p. 7-17Article in journal (Refereed)
    Abstract [en]

    It is of a vital importance to reduce the frictional losses in the engines and hence the fuel/energy consumption. The major contributors to this are the oil control ring and cylinder liner interactions difficult to understand when comparing the experimental and theoretical results. The latter largely depend on the liner surface measurement and filtering type used in the simulations. Therefore, low-pass and high-pass filtrations were applied and the friction behaviors between the filtered liner surfaces and a perfectly flat ring surface were simulated for different engine speeds. The surfaces low-pass filtered by lower cutoffs showed higher friction, while the type of de-noising revealed about two and a half times higher friction. Stylus surfaces showed larger friction than the interference ones. © 2015 Elsevier Ltd. All rights reserved.

  • 185.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Tomanik, Eduardo
    Mahle Metal Leve, Jundiai - Sao Paulo, Brazil.
    Profito, Francisco
    University of Sao Paulo, Sao Paulo – SP, Brazil.
    Influence of Surface Waviness on Predictions of Friction between Cylinder Liner and Oil Control Ring2015In: Proceedings of the 42nd Leeds – Lyon Symposium on Tribology, September 7-9, 2015, Lyon, France, 2015Conference paper (Refereed)
    Abstract [en]

    It is of a vital importance for automotive industry to reduce the frictional losses in internal combustion engines and hence their fuel consumption and CO2 emissions. The major contributors to this are the oil control ring (OCR) and cylinder liner interactions. These interactions are of complex multi-physics and multi-scale nature and many attempts have been made to improve the modelling and understanding of the phenomena involved. Even though continuous improvements have been made (see for ex. [1-3]), the form, waviness and roughness variation of real engineering surfaces still cause a large scatter in the results. The most of the models include measured liner surfaces, which are then filtered to capture the micro-effects of the roughness scale. However, by doing this, the contact conditions change (asperity contact distributes more evenly, see Fig. 1) such that the part of the boundary friction reduces and the part of the hydrodynamic friction increases accordingly for a given engine speed. This study focuses on one of these multi-scale problems, namely on how the 3D measurement type/size and filtering affects the predictions of friction between cylinder liner and OCR of truck engines. Two types of 3D liner surface measurements were investigated: (i) interference (with an objective of 2.5x, size of 2.5x3.3mm) and (ii) 4x8mm stylus measurement. The form was removed by fitting and subtracting a 2nd order polynomial and the waviness was filtered out by using a robust Gaussian filter with three different cutoffs: 2.5mm, 0.8mm and 0.25mm. The friction behaviours (i.e. the Friction Mean Effective Pressure-FMEP) between the primary/ filtered liner surfaces and a perfectly flat ring surface were then simulated for different engine speeds. The relative errors of the OCR’s FMEPs with respect to the primary surface were evaluated and results discussed.

  • 186.
    Dimkovski, Zlate
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Yoann, Charon
    Perrier, Maxime
    Cabanettes, Frédéric
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Rosén, Bengt-Göran
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    A Sensitivity Study of the Tribotesting Setup to Rate Different Liner Surfaces2012In: 15th Nordic Symposium on Tribology: NordTrib 2012, Trondheim, 2012Conference paper (Refereed)
  • 187.
    Dincay, Berkan
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    GPS/Optical Encoder Based Navigation Methods for dsPIC Microcontroled Mobile Vehicle2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Optical encoders are being widely suggested for precise mobile navigation. Combining such sensor information with Global Positioning System (GPS) is a practical solution for reducing the accumulated errors from encoders and moving the navigational base into global coordinates with high accuracy.

    This thesis presents integration methods of GPS and optical encoders for a mobile vehicle that is controlled by microcontroller. The system analyzed includes a commercial GPS receiver, dsPIC microcontroller and mobile vehicle with optical encoders. Extended kalman filtering (EKF), real time curve matching, GPS filtering methods are compared and contrasted which are used for integrating sensors data. Moreover, computer interface, encoder interface and motor control module of dsPIC microprocessor have been used and explained.

    Navigation quality on low speeds highly depends greatly upon the processing of GPS data. Integration of sensor data is simulated for both EKF and real time curve matching technique and different behaviors are observed. Both methods have significantly improved the accuracy of the navigation. However, EKF has more advantages on solving the localization problem where it is also dealing with the uncertainties of the systems.

  • 188. Duncalf, Alexandra
    et al.
    Persson, Katarina
    Chamma, Alexander
    ConneXion2015Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 189.
    Dunert, Sofie
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Kristoffersson, David
    Halmstad University, School of Business and Engineering (SET).
    Zilent Ocean: EL-KONVERTERING AV INOMBORDSMOTORER TILL SEGELBÅTAR2009Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Through extensive research it has shown that today’s sail boat owners are very frustrated concerning the limited choice of engine alternatives offered by today’s market. Besides rising fuel-costs, environmental awareness is very important in today’s society. Hence it is vital to find alternative environmental-friendly motors and replace combustion-engines.

     

    Zilent Ocean is an extensive project within Development engineering program at Halmstad University. The Project aims at minimizing environmental impact on our seas through limiting the usage of combustion-engines in sail boats. Zilent Ocean’s major target is the development of a customer-oriented company offering electric conversion kits of combustion-engines to sail boats at very competitive market prices.

     

    The Project was carried out by converting the combustion-engine in a MAXI 77 sailing boat (7.7m length, 5 beds). The current diesel-engine installed in the boat was replaced with a new DC electrical engine together with the appropriate controller unit.

     

    The finished sail boat prototype will be evaluated under the summer of 2009. The sail boat contains unique solutions enabling a more cost-efficient system in comparison with today’s combustion-engines. The aim is to provide a complete electric conversion kit at a lower price than a new combustion-engine. Together with lower investment costs, minimal maintenance and running costs, electrical conversion from Zilent Ocean is bound to be the future, and the natural decision for many sailors in Scandinavia.

  • 190.
    Eckerljung, Daniel
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Hugoh, Jakob
    Halmstad University, School of Business and Engineering (SET).
    Framtagande av ställbar krok för hängränna2013Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project was to design an adjustable gutter bracket for Lindab Profil AB. Lindab currently manufacture a gutter bracket that is adjustable in angle, however, this model has some drawbacks.  One of it´s shortcomings is that it is somewhat difficult for the customer to mount.  Another problem with Lindab’s current model is that the design makes manufacturing unnecessarily complex. The new gutter bracket, that we have constructed, does not have these problems. It is adjustable for different roof pitches. It is easy to mount to the fascia board and the manufacturing process has been simplified as well.

    In the project we have used a design methodology developed by Fredy Olsson.  In addition to designing the product we have performed FEM analysis, to ensure that it will endure  loads and stress.  We have used the CAD software Catia v5 for this, and for the 3d models. Drawings are attached to  the document.

  • 191.
    Edman, Fredrik
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Jansson, Jonathan
    Halmstad University, School of Business, Engineering and Science.
    Aerodynamiskt fotstöd: Utveckling av individanpassat fotstöd för paracyklist2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has focused on aerodynamics in hand cycling. Hand cycles are used by people with disabilities, paralysis or amputation of a lower limb.

    The idea for the project was initiated by a para-cyclist who suspected that his feet were causing an unnecessarily large air resistance when racing. The aim of this project was therefore to investigate this suspicion. If the excessive air resistance was confirmed, a new footrest would be developed to reduce it. The project was conducted in collaboration with the orthopedic clinic Team Olmed who had previously had contact with the user.

    Simulations on the feet were carried out in FloEFD to investigate the air resistance caused by the feet. Any excessive air resistance could then be confirmed and the development of a new footrest that would reduce drag could begin. Through literature studies regarding aerodynamics and analogies, brainstorming and brainwriting and with help from experts different concepts were generated. The concept of a streamlined footrest served as a basis to reduce the air resistance. Two of the concepts were modeled with a rounded shape that gently breaks the air and forms a streamline along the body. New simulations were conducted and later compared with the old footrest and the new streamline characteristics could then be confirmed.

    The result of the post simulations cannot be definitively quantified, but they indicate that air resistance is reduced by about 0,3 N for the two new footrests. This represents an improvement of 12-15 seconds for the cyclist on a 20 km race, which could be crucial in future competitions. The concept that provided the lowest air resistance was also developed as a prototype. The prototype was tested on the user's bicycle and feet with a satisfactory result.

    The project shows that it is relevant to develop more aerodynamic footrests in the sport hand- cycling. The time saved with the footrest developed in this project had meant the difference between victory and a fourth place at the Paralympics in 2008.

  • 192.
    Edqvist, Ola
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Abbas, Rand
    Halmstad University, School of Business, Engineering and Science.
    Konstruktion av justerbart sågstöd2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 193. Ekelund, Anna
    et al.
    Standar, Eric
    ecGo - Charge, Pay & Go!2015Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 194. Ekelund, Johan
    et al.
    Nilsson, Martin
    Anslagstavlan VERA2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 195. Ekeroth, Emil
    et al.
    Hultin, Joel
    ClickitUp2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 196.
    Ekeroth, Tobias
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Forssmark, Linda
    Halmstad University, School of Business and Engineering (SET).
    TELF: Vänder rätt i nöd2012Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract

    In year 2011 95 people drowned, that is an increase of 16 persons from 2010. Drowning in connection with boats is the most common cause and in year 2010 29 persons died in connection with boats.

    When rescue crew arrive to an scene of accident with a capsized boat they must improvise the rescue. It is very important that they turn the capsized boat to the right keel in order to secure that no one is stuck under the boat. The rescue crew cannot leave an abandoned boat out on the sea because it can cause new accidents and to tow a boat on the wrong keel is very difficult.

    TELF is a tool that facilitate the rescue with capsized boats. With TELF the rescue crew do not have to improvise the rescue work, they know directly what to do. TELF throws over the capsized boat and with the rescue boat as a counterforce they can drag the boat to its right keel again.

    TELF is designed to a turn capsized boats to its right keel, but it can also be used to drag a burning boat out from the harbour to avoid other boats from catching the fire. With TELF the rescue crew can feel secure, they do not have to improvise the rescue work, now they know directly what to do. 

  • 197.
    Eklund, Gustav
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Kaldner, Gustav
    Halmstad University, School of Business, Engineering and Science.
    5+2 Säteskoncept: Framtagning och anpassning av tredje stolsrad för CMA 1.52019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet innefattar en konceptgenerering av en tredje stolsrad och om dess anpassning till plattformen CMA (Compact Modular Architecture) 1.5. Konceptgenereringen av produkten täcker områdena konstruktion, tillämpning, hållfasthetsberäkning, materialval samt hur produkten slutligen skall monteras i karossen. Målet var att med hjälp av en benchmarkanalys konstruera ett underlag för uppdragsgivaren CEVT AB att vidareutveckla för att sedan kunna tillämpa lösningen som ett tillval i framtida bilar.  Projektet resulterade i ett koncept med 5 komponenter som är anpassade utefter den utformning som fanns på plattformen idag. För att möjliggöra en tillämpning resulterade projektet också i en ändring av uppdragsgivarens befintliga förstärkningar som då också stärker projektgruppens konstruktion.  Resultatet konstruerades och beräknades i CATIA V5 som sedan har renderats i Keyshot 8 för en visuell presentation av arbetet.

  • 198.
    Ekström, Johan
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Mickelsson, Rikard
    Halmstad University, School of Business and Engineering (SET).
    Auto Deco Primer Valve2012Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Auto Deco Primer Valve är ett projekt som har resulterat i ett förenklat startsystem för tvåtaktsmotorer.

    Att starta en tvåtakts motor med dragsnöre är både tidskrävande och jobbigt, därför vill projektgruppen ge samhället en lösning på problemet.

    Genom ett befintligt koncept har syftet varit att fullborda detta system genom en ny innovativ lösning i form av en multifunktionel ventillösning.

     

    Ventilen och dess ingående system är tänkt att ersätta två funktioner som återfinns på de flesta tvåtaktsmotorer idag: Dekompressionsventil och Chokereglage

     

    Vår nya ventil gör att det tidigare manuella systemet automatiskt, och tar på så sätt bort de steg som måste utföras innan motorn startas.

     

    Det nya systemet som förverkligas i ”Auto Deco Primer Valve” kommer att medföra många fördelar som beskrivs utförligare längre fram i rapporten.

     

    Målet vid projektets slut har varit att ta fram en fungerande prototyp vilket projektgruppen har åstadkommit.

    Arbetet har inneburit en stor del av kreativt tänkande, för att kunna kombinera vetenskap om bland annat pneumatik med ett mekaniskt system.

     

    För att bygga ett hållbart system som klarar marknadens tuffa krav och samtidigt inte är beroende av elektricitet så har stor del av arbetet bestått av att utveckla, beräkna, dimensionera, samt förenklat systemets olika delar och sedan modellera detta i Catia V5 R20.

     

    Projektet har resulterat i en funktionsprototyp med fullständigt CAD-underlag som Husqvarna AB kommer att använda till att vidareutveckla systemet.  

    Med detta arbete vill vi ge samhället och framförallt skogsbranschen ett tillförlitligare hjälpmedel, genom en ny innovativ lösning, som gör att ett motorsystem för tvåtaktsmotorer blir mer driftsäkert, lättare att använda och snabbare att starta.

  • 199.
    Elghoul, Zoelfikar
    Halmstad University, School of Business and Engineering (SET).
    Manganese phosphate coating mini-line lab2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The following report is conducted in collaboration with the University of Halmstad. As the development of today's vehicles demands environmentalregulations require reduced emissions of CO2, performance, economy and safety, Lighter and efficient vehicles in transmission, this intensive development coupledwith re-optimization of the conflicting demands driveability, durability,efficiency and noise comfort. During the past 10 year the design margins hasbeen reduced. This means that the former research experience must be renewedfor development continues. As a part of the research conducted at HalmstadUniversity is an interest in being able to prepare these surfaces in different ways,in a lab environment. In this thesis, two processes in question, manganesephosphate and coating treatment.

    The purpose of this project is to construct a mini lab which will achieve theprocess of the surface treatment of machine element components in a laboratoryenvironment.

    The purpose of this project is to design and control the process which willconfigure all the details and specification required to achieve stagesof phosphate process as well the properties of every details in the chain ofimmersion and safety environment during the process stages, the task alsoincluding Risk analysis.

    The method that used was the same that was used by us during earlier courses inconstruction method written by Fredy Olsson, method principle /primary andmanufacturing. The development of the design has been done using brainstorming. The basic idea is a common idea where this since developed into aprototype.

  • 200.
    Elghoul, zoelfikar
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    John, Shobin
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK), Functional Surfaces.
    Surface Topographical  Analysis Of Cutting Inserts2016Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The following report conducted with collaboration of the University of Halmstad and ABSandvik Coromant.The focus of the project is characterizing the surface topography of different surface treatmentvariants before and after chemical vapor deposition (CVD).As a part of improving the knowledge about the surface area characterization and accomplisha better knowledge and understanding about surfaces and its relation to wear of uncoatedWC/Co cutting tools The project initiated in February 2016 and end date was set to May2016.The methodology used in this thesis based on the statistical analysis of surface topographicalmeasurements obtained from interferometer and SEM by using Digital-Surf-MountainsMapsoftware.The finding from this thesis showed that Mean and Standard deviation method, Spearman’scorrelation analysis and Standard deviation error bar followed by ANOVA and T-test areeffective and useful when comparing between different variants.The thesis resulted in a measurement approach for characterizing different surfacetopographies using interferometer and SEM together with statistical analysis.Keywords: 3D-Surfaces Texture, CVD coating inserts, Interferometer, Spearman’s correlation andANOVA & T-test.

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