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  • 1.
    Amouzgar, Kaveh
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Rashid, Asim
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Multi-Objective Optimization of a Disc Brake System by using SPEA2 and RBFN2013In: ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference: Volume 3B: 39th Design Automation ConferencePortland, Oregon, USA, August 4–7, 2013, New York: American Society of Mechanical Engineers , 2013Conference paper (Other academic)
    Abstract [en]

    Many engineering design optimization problems involve multiple conflicting objectives, which today often are obtained by computational expensive finite element simulations. Evolutionary multi-objective optimization (EMO) methods based on surrogate modeling is one approach of solving this class of problems. In this paper, multi-objective optimization of a disc brake system to a heavy truck by using EMO and radial basis function networks (RBFN) is presented. Three conflicting objectives are considered. These are: 1) minimizing the maximum temperature of the disc brake, 2) maximizing the brake energy of the system and 3) minimizing the mass of the back plate of the brake pad. An iterative Latin hypercube sampling method is used to construct the design of experiments (DoE) for the design variables. Next, thermo-mechanical finite element analysis of the disc brake, including frictional heating between the pad and the disc, is performed in order to determine the values of the first two objectives for the DoE. Surrogate models for the maximum temperature and the brake energy are created using RBFN with polynomial biases. Different radial basis functions are compared using statistical errors and cross validation errors (PRESS) to evaluate the accuracy of the surrogate models and to select the most accurate radial basis function. The multi-objective optimization problem is then solved by employing EMO using the strength Pareto evolutionary algorithm (SPEA2). Finally, the Pareto fronts generated by the proposed methodology are presented and discussed.

  • 2.
    Amouzgar, Kaveh
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    University of West.
    An approach towards generating surrogate models by using RBFN with a apriori bias2014In: Proceedings of the ASME 2014 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference IDETC/CIE 2014 August 17-20, 2014, Buffalo, NY, USA, American Society of Mechanical Engineers (ASME) , 2014Conference paper (Refereed)
    Abstract [en]

    In this paper, an approach to generate surrogate modelsconstructed by radial basis function networks (RBFN) with a prioribias is presented. RBFN as a weighted combination of radialbasis functions only, might become singular and no interpolationis found. The standard approach to avoid this is to add a polynomialbias, where the bias is defined by imposing orthogonalityconditions between the weights of the radial basis functionsand the polynomial basis functions. Here, in the proposed a prioriapproach, the regression coefficients of the polynomial biasare simply calculated by using the normal equation without anyneed of the extra orthogonality prerequisite. In addition to thesimplicity of this approach, the method has also proven to predictthe actual functions more accurately compared to the RBFNwith a posteriori bias. Several test functions, including Rosenbrock,Branin-Hoo, Goldstein-Price functions and two mathematicalfunctions (one large scale), are used to evaluate the performanceof the proposed method by conducting a comparisonstudy and error analysis between the RBFN with a priori and aposteriori known biases. Furthermore, the aforementioned approachesare applied to an engineering design problem, that ismodeling of the material properties of a three phase sphericalgraphite iron (SGI) . The corresponding surrogate models arepresented and compared

  • 3.
    Berglund, Simon
    et al.
    Jönköping University, School of Engineering, JTH, Product Development.
    Lennartsson, Joel
    Jönköping University, School of Engineering, JTH, Product Development.
    Design of Power Off Brake: Utveckling av testutrustning2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal with this thesis is to find together with Saab Avionics Systems the correlation between applied current, air gap and forces that a brake with an electromagnetic release function have. This is achieved through theoretical calculations and practical tests.  

    At the moment the brakes are used in electromechanical actuators that are applied in aircraft flap systems.

    These brakes have been in Saab’s collection of products since a decade and to keep on being a competitive supplier they need to optimize their design process. However, there are difficulties regarding calculating the force of the magnetic field of these brakes since it is very complicated. To better understand how the design can be altered the current product Power Off Brake needs to be tested and analyzed.  

    The test equipment that was developed is designed so that the brake dimension, air gap and current can vary alongside a change of surrounding temperature. After a test in room temperature it was found that the test equipment had a margin of error about 10%.

    By testing Power Off Brake with the selected measuring method and test equipment Saab will get one step closer to better understand the relationship between theoretical calculations and practical tests. This can be used to reduce the safety margins when new brakes are to be developed since the test results provide insight about what happens when saturation in the material occur and how the brake perform in environmental conditions of an aircraft.

    Furthermore, the authors leave recommendations for continued work and suggestions for improved design.

  • 4.
    Burman, Erik
    et al.
    Department of Mathematics, University College London.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University.
    Stenberg, Rolf
    Department of Mathematics and Systems Analysis, Aalto University.
    Galerkin least squares finite element method for the obstacle problem2017In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 313, p. 362-374Article in journal (Refereed)
    Abstract [en]

    We construct a consistent multiplier free method for the finite element solution of the obstacle problem. The method is based on an augmented Lagrangian formulation in which we eliminate the multiplier by use of its definition in a discrete setting. We prove existence and uniqueness of discrete solutions and optimal order a priori error estimates for smooth exact solutions. Using a saturation assumption we also prove an a posteriori error estimate. Numerical examples show the performance of the method and of an adaptive algorithm for the control of the discretization error.

  • 5.
    Cenanovic, Mirza
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization. Jönköping University, School of Engineering, JTH, Product Development.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G,
    Umeå University.
    Minimal surface computation using a finite element method on an embedded surface2015In: International Journal for Numerical Methods in Engineering, ISSN 0029-5981, E-ISSN 1097-0207, Vol. 104, no 7, p. 502-512Article in journal (Refereed)
    Abstract [en]

    We suggest a finite element method for finding minimal surfaces based on computing a discrete Laplace–Beltrami operator operating on the coordinates of the surface. The surface is a discrete representation of the zero level set of a distance function using linear tetrahedral finite elements, and the finite element discretization is carried out on the piecewise planar isosurface using the shape functions from the background three-dimensional mesh used to represent the distance function. A recently suggested stabilized scheme for finite element approximation of the mean curvature vector is a crucial component of the method.

  • 6.
    Cenanovic, Mirza
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larsson, Mats G.
    Umeå University.
    Cut finite element modeling of linear membranes2016In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 310, p. 98-111Article in journal (Refereed)
    Abstract [en]

    We construct a cut finite element method for the membrane elasticity problem on an embedded mesh using tangential differential calculus, i.e., with the equilibrium equations pointwise projected onto the tangent plane of the surface to create a pointwise planar problem in the tangential direction. Both free membranes and membranes coupled to 3D elasticity are considered. The discretization of the membrane comes from a Galerkin method using the restriction of 3D basis functions (linear or trilinear) to the surface representing the membrane. In the case of coupling to 3D elasticity, we view the membrane as giving additional stiffness contributions to the standard stiffness matrix resulting from the discretization of the three-dimensional continuum.

  • 7.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    A mixed method for elasticity with the curl of displacements as a drilling degree of freedomManuscript (preprint) (Other academic)
    Abstract [en]

    We present a mixed method for the linearized elasticity equations with independent approximation of the curl of the displacements.The curl can be seen as a drilling degree of freedom allowing for coupling with rotating objects and the direct application of moments of force.

  • 8.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Nonconforming rotated Q1 tetrahedral element with explicit time stepping for elastodynamics2012In: International Journal for Numerical Methods in Engineering, ISSN 0029-5981, E-ISSN 1097-0207, Vol. 91, no 10, p. 1105-1114Article in journal (Refereed)
    Abstract [en]

    In this paper, we apply a rotated bilinear tetrahedral element to elastodynamics in R3. This element performs superior to the constant strain element in bending and, unlike the conforming linear strain tetrahedron, allows for row-sum lumping of the mass matrix. We study the effect of different choices of approximation (point- wise continuity versus edge average continuity) as well as lumping versus consistent mass in the setting of eigenvibrations. We also use the element in combination with the leapfrog method for time domain com- putations and make numerical comparisons with the constant strain and linear strain tetrahedra. 

  • 9.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats
    Intrinsic finite element modeling of a linear membrane shell problem2012Report (Other academic)
    Abstract [en]

    A Galerkin finite element method for the membrane elasticity problem on a meshed surface is constructed by using two-dimensional elements extended into three dimensions. The membrane finite element model is established using the intrinsic approach suggested by Delfour and Zol´esio.

  • 10.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats
    Umeå Universitet.
    Locking free quadrilateral continuous/discontinuous finite element methods for the Reissner–Mindlin plate2014In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 269, p. 381-393Article in journal (Refereed)
    Abstract [en]

    We develop a finite element method with continuous displacements and discontinuous rotations for the Reissner-Mindlin plate model on quadrilateral elements. To avoid shear locking, the rotations must have the same polynomial degree in the parametric reference plane as the parametric derivatives of the displacements, and obey the same transforma- tion law to the physical plane as the gradient of displacements. We prove optimal conver- gence, uniformly in the plate thickness, and provide numerical results that confirm our estimates. 

  • 11.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Umeå University.
    A posteriori error estimates for continuous/discontinuous Galerkin approximations of the Kirchhoff–Love buckling problem2015In: Computational Mechanics, ISSN 0178-7675, E-ISSN 1432-0924, Vol. 56, no 5, p. 815-827Article in journal (Refereed)
    Abstract [en]

    Second order buckling theory involves a oneway coupled coupled problem where the stress tensor from a plane stress problem appears in an eigenvalue problem for the fourth order Kirchhoff plate. In this paper we present an a posteriori error estimate for the critical buckling load and mode corresponding to the smallest eigenvalue and associated eigenvector. A particular feature of the analysis is that we take the effect of approximate computation of the stress tensor and also provide an error indicator for the plane stress problem. The Kirchhoff plate is discretized using a continuous/discontinuous finite element method based on standard continuous piecewise polynomial finite element spaces. The same finite element spaces can be used to solve the plane stress problem.

  • 12.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Umeå University.
    Finite element modeling of a linear membrane shell problem using tangential differential calculus2014In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 270, p. 1-14Article in journal (Refereed)
    Abstract [en]

    We construct a new Galerkin finite element method for the membrane elasticity problem on a meshed surface by using two-dimensional elements extended into three dimensions. The membrane finite element model is established using a tangential differential calculus approach that avoids the use of classical differential geometric methods. The finite element method generalizes the classical flat element shell method where standard plane stress elements are used for membrane problems. This makes our method applicable to a wider range of problems and of surface descriptions, including surfaces defined by distance functions. 

  • 13.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Umeå University.
    Larsson, Fredrik
    Chalmers University of Technology.
    Tangential differential calculus and the finite element modeling of a large deformation elastic membrane problem2015In: Computational Mechanics, ISSN 0178-7675, E-ISSN 1432-0924, Vol. 56, no 1, p. 87-95Article in journal (Refereed)
    Abstract [en]

    We develop a finite element method for a large deformation membrane elasticity problem on meshed curved surfaces using a tangential differential calculus approach that avoids the use of classical differential geometric methods. The method is also applied to form finding problems.

  • 14.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Umeå University.
    Larsson, Karl
    Umeå University.
    Variational formulation of curved beams in global coordinates2014In: Computational Mechanics, ISSN 0178-7675, E-ISSN 1432-0924, Vol. 53, no 4, p. 611-623Article in journal (Refereed)
    Abstract [en]

    In this paper we derive a variational formulation for the static analysis of a linear curved beam natively expressed in global Cartesian coordinates. Using an implicit description of the beam midline during derivation we eliminate the need for local coordinates. The only geometrical information appearing in the final expressions for the governing equations is the tangential direction. As a consequence, zero or discontinuous curvature, for example at inflection points, pose no difficulty in this formulation. Kinematic assumptions encompassing both Timoshenko and Euler-Bernoulli beam theories are considered. With the exception of truly three-dimensional formulations, models for curved beams found in the literature are typically derived in the local Frenet frame. We implement finite element methods with global degrees of freedom and discuss curvature coupling effects and locking. Numerical comparisons with classical solutions for straight and curved cantilever beams under tip load are given, as well as numerical examples illustrating curvature coupling effects. 

  • 15.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization. Jönköping University, School of Engineering, JTH, Product Development.
    Rashid, Asim
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Salomonsson, Kent
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Least-squares stabilized augmented Lagrangian multiplier method for elastic contact2016In: Finite elements in analysis and design (Print), ISSN 0168-874X, E-ISSN 1872-6925, Vol. 116, p. 32-37Article in journal (Refereed)
    Abstract [en]

    In this paper, we propose a stabilized augmented Lagrange multiplier method for the finite element solution of small deformation elastic contact problems. We limit ourselves to friction-free contact with a rigid obstacle, but the formulation is readily extendable to more complex situations.

  • 16.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Salomonsson, Kent
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    A discontinuous Galerkin method for cohesive zone modelling2015In: Finite elements in analysis and design (Print), ISSN 0168-874X, E-ISSN 1872-6925, Vol. 102-103, p. 1-6Article in journal (Refereed)
    Abstract [en]

    We propose a discontinuous finite element method for small strain elasticity allowing for cohesive zone modeling. The method yields a seamless transition between the discontinuous Galerkin method and classical cohesive zone modeling. Some relevant numerical examples are presented. 

  • 17.
    Hofwing, Magnus
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Robustness Analysis of Residual Stresses in Castings2011Doctoral thesis, comprehensive summary (Other academic)
  • 18.
    Hofwing, Magnus
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Robustness of residual stresses in brake discs by metamodeling2011In: the ASME 2011 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, 2011Conference paper (Other academic)
  • 19.
    Hofwing, Magnus
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Tapankov, Martin
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Optimal Polynomial Regression Models by using a Genetic Algorithm2011In: Proceedings of the second International Conference on Soft Computing Technology in Civil, Structural and Environmental Engineering / [ed] Yiannis Tsompanakis; B H V Topping, 2011Conference paper (Refereed)
  • 20.
    Isaksson, Ola
    et al.
    GKN Aerospace Sweden AB.
    Bertoni, Marco
    Blekinge Tekniska Högskola, Institutionen för maskinteknik.
    Hallstedt, Sophie
    Blekinge Tekniska Högskola, Institutionen för strategisk hållbar utveckling.
    Lavesson, Niklas
    Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik.
    Model Based Decision Support for Value and Sustainability in Product Development2015Conference paper (Refereed)
    Abstract [en]

    Decomposing and clarify “sustainability” implications in the same way as concrete targets on product functionality is challenging, mainly due to the problem of showing numbers and ‘hard facts’ related to the value generated by sustainability-oriented decisions. The answer lies in methods and tools that are able, already in a preliminary design stage, to highlight how sustainable design choice can create value for customers and stakeholders, generating market success in the long term. The paper objective is to propose a framework where Sustainable Product Development (SPD) and Value Driven Design (VDD) can be integrated to realize a model-driven approach to support early stage design decisions. Also, the paper discusses how methods and tools for Model-Based Decision Support (MBDS) (e.g., response surface methodology) can be used to increase the computational efficiency of sustainability- and value-based analysis of design concepts. The paper proposes a range of activities to guide a model-based evaluation of sustainability consequences in design, showing also that capabilities exist already today for combining research efforts into a multi disciplinary decision making environment.

  • 21.
    Karlsson, Elin
    Jönköping University, School of Engineering.
    Utveckling av frånluftsfläkt: Omkonstruktion av frånluftsfläkt för uppfyllande av Ecodesigndirektivet för år 20182018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 22.
    Karlsson, Sebastian
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Boberg, André
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Dämpning av ljud i Shift-by-Wire växelväljare: Noise damping in a Shift-by-Wire gear shifter2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Constantly growing demands from the costumers in the Automotive industry forces the subcontractors to seek alternative ways to compete. One parameter of quality is the components tolerance against NVH(Noise, Vibraion & Harshness) aspects. Kongsbergs Automotive has developed a new gear shifter platform (Shift-by-Wire) that is sold to Alfa Romeo and used in of their car models. However, the company is not pleased with the components sound quality, therefore the main purpose of this thesis is to develope a number of concepts that is supposed to enhance these NVH-aspects.

    To get an understanding of the problem an analysis of the causes of the emitted sound has been done parallell to a product decomposition, function decomposition and a Ishikawa-diagram. Together with these methods has a litterature study been performed to get familiar with the physics of an impact and especially the emittment of noise. The concepts has been generated through a combined brainstorming and brainwriting session. A number of concepts has been developed that should reduce emitted noise. To evaluate the concepts generated has well proven methods for screening been used, such as: analysis of pros and cons, feasibility analyis and Go/No-Go.

    The definite concept uses a method that absorbs the kinetic energy induced by the user through a built-on component and an energy absorbing foam. The idéa is that the built-on component and the foam should transform more of the kinetic energy to heat energy.

    The consequenses of this study is that the company now has a fully applicable concept to evaluate the idés effectiveness regarding reduction of noise. Next step is to make a prototype and evaluate the idéa.

    Since the making of a prototype has not been done, the biggest restriction in the thesis  is that the developed concept is not evaluated regarding its effectiveness of reduction of noise.

  • 23.
    Klarbring, Anders
    et al.
    Linköping university.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    A Note on the Min-Max Formulation of Stiffness Optimization including Non-Zero Prescribed Displacements2012In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 45, no 1, p. 147-149Article in journal (Refereed)
    Abstract [en]

    The present theoretical note shows how a naturalobjective function in stiffness optimization, including bothprescribed forces and non-zero prescribed displacements,is the equilibrium potential energy. It also shows how theresulting problem has a saddle point character that may beutilized when calculating sensitivities.

  • 24.
    Klarbring, Anders
    et al.
    Linköping university.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Topology optimization of hyperelastic bodies including non-zero prescribed displacements2013In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 47, no 1, p. 37-48Article in journal (Refereed)
    Abstract [en]

    Stiffness topology optimization is usually based on a state problem of linear elasticity, and there seems to be little discussion on what is the limit for such a small rotation-displacement assumption. We show that even for gross rotations that are in all practical aspects small (<3 deg), topology optimization based on a large deformation theory might generate different design concepts compared to what is obtained when small displacement linear elasticity is used. Furthermore, in large rotations, the choice of stiffness objective (potential energy or compliance), can be crucial for the optimal design concept. The paper considers topology optimization of hyperelastic bodies subjected simultaneously to external forces and prescribed non-zero displacements. In that respect it generalizes a recent contribution of ours to large deformations, but we note that the objectives of potential energy and compliance are no longer equivalent in the non-linear case. We use seven different hyperelastic strain energy functions and find that the numerical performance of the Kirchhoff–St.Venant model is in general significantly worse than the performance of the other six models, which are all modifications of this classical law that are equivalent in the limit of infinitesimal strains, but do not contain the well-known collapse in compression. Numerical results are presented for two different problem settings.

  • 25.
    Larsson, Johan
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Vakuumlift2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is a cooperation with E.MIL Energi & Miljö, a company that mostly works with helping other companies to reduce and improve their usage of energy.

    This project aims to develop a product which helps people, that due to different reasons, has reduced mobility to pick up belongings from the floor. It can be things like screws, pills and other stuff. The purpose of this project is to be able to produce a product that will solve this need without having the accuracy that is required by a gripper.

    Two central questions have been addressed in the project:

    1. How is the best way to produce a product that helps people to pick up things from the floor?

    2. How does the design process look like when developing "Sugpellen"?

    The methods that have been used is specifications for requirements, competitor analysis, screening, and finally the CAD model with 3D printed model and also a development of a prototype.

    Two different kinds of solutions have been prepared which basically has the same ground functions. The product has a neck, filter, head, handle, fan and batteries. What separates the two alternatives with each other is that one of them has fifteen batteries which gives a more bigger and robust design. The other model has Lithium-Ion batteries that will be placed inside the handle and gives a smaller and more attractive design.

    This product needs to be developed further before it is ready to enter the market. There are some things that still are missing before it is completely finished for instance strength analysis and material selection and also decide which types of batteries that should be used.

  • 26.
    Mellberg, Anders
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Extension – Operator Environment for ForestHarvesters2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A forest harvester operator is today facing a stressful work environment with a high demand on coordination skills and effectiveness to run the operation with positive economical outcome. The learning phase is very long compared to similar work.The vision for this project was to transform the machine, through intuitive and innovative interface design, into an extension of the operator’s body. In this way it provides higher productivity as well as user friendliness, shorter learning phase and a healthier work situation.This was realized through the use of prior but yet not market available related research. Through market studies, applicable technology already available in other industries was found. The result is a complete seat with controls for a conceptual Gremo harvester realizable in the year 2023.

  • 27.
    Olofsson, Jakob
    Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Simulation of Microstructure-based Mechanical Behaviour of Cast Components2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the process of developing cast iron and cast aluminium components, a high level of co-operation between product development and production is of great importance. From an engineering standpoint, this co-operation is limited early in the product development phase by e.g. a lack of established methods for the consideration of local variations in the mechanical behaviour of a finished component.

    This thesis aims to increase the possibilities for co-operation between product development and production during the product realisation process by introducing and studying the use of predicted local mechanical behaviour in structural analyses of cast components. A literature review of existing simulation methods and a work on characterisation of mechanical behaviour from microstructural features have been performed to identify important knowledge gaps. A simulation strategy has been formulated which is able to predict local mechanical behaviour throughout the entire component, and to incorporate this into a Finite Element Method (FEM) simulation of the structural behaviour of the component. In the simulation strategy, componentspecific microstructure-based mechanical behaviour is predicted using a casting process simulation. A computer program was developed to create FEM material definitions which capture the local variations in mechanical behaviour throughout the component. Using a material reduction technique, the local mechanical behaviour can be incorporated without increasing the FEM simulation time.

    The relevance of the simulation strategy was experimentally verified on cast aluminium samples, where the strain field was observed using Digital Image Correlation (DIC). It was found that the local variations in mechanical behaviour cause a stress-strain distribution that deviates from that predicted by a homogeneous material description, indicating the importance of calculating with and including such variations in material behaviour in FEM simulations. Numerical investigations demonstrate the strategy’s relevance for predicting the behaviour of cast aluminium and ductile iron components.

  • 28.
    Olofsson, Jakob
    et al.
    Jönköping University, School of Engineering, JTH, Materials and Manufacturing. Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Salomonsson, Kent
    Jönköping University, School of Engineering, JTH, Product Development. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Svensson, Ingvar L.
    Jönköping University, School of Engineering, JTH, Materials and Manufacturing. Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Modelling and simulations of ductile iron solidification-induced variations in mechanical behaviour on component and microstructural level2015In: IOP Conference Series: Materials Science and Engineering, Volume 84: MCWASP XIV: International Conference on Modeling of Casting, Welding and Advanced Solidification Processes / [ed] Hideyuki Yasuda, Kyoto University, Japan, London: Institute of Physics Publishing (IOPP), 2015, Vol. 84, p. 1-8Conference paper (Refereed)
    Abstract [en]

    The mechanical behaviour and performance of a ductile iron component is highly dependent on the local variations in solidification conditions during the casting process. Here we show a framework which combine a previously developed closed chain of simulations for cast components with a micro-scale Finite Element Method (FEM) simulation of the behaviour and performance of the microstructure. A casting process simulation, including modelling of solidification and mechanical material characterization, provides the basis for a macro-scale FEM analysis of the component. A critical region is identified to which the micro-scale FEM simulation of a representative microstructure, generated using X-ray tomography, is applied. The mechanical behaviour of the different microstructural phases are determined using a surrogate model based optimisation routine and experimental data. It is discussed that the approach enables a link between solidification- and microstructure-models and simulations of as well component as microstructural behaviour, and can contribute with new understanding regarding the behaviour and performance of different microstructural phases and morphologies in industrial ductile iron components in service.

  • 29.
    Olofsson, Jakob
    et al.
    Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Svensson, Ingvar L.
    Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Closed chain simulations of a cast aluminium component - Incorporating casting process simulation and local material characterization into stress-strain simulations2014In: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 54, no 2, p. 259-265Article in journal (Refereed)
    Abstract [en]

    The coupling between simulations of solidification, microstructure and local mechanical behaviour and simulation of stress-strain behaviour is studied by applying a recently developed simulation strategy to a high pressure die cast aluminium component. In the simulation strategy, named a closed chain of simulations for cast components, the mechanical behaviour throughout the component is determined locally by a casting process simulation. The entire casting process, including mould filling and solidification, is simulated to predict the formation of microstructure and residual stresses throughout the component, and material characterization models are applied to relate microstructural features to local elastic and plastic mechanical material behaviour. The local material behaviour is incorporated into a finite element method (FEM) stress-strain simulation of a realistic load case of the component in service.

    In the current contribution the influences of local variations in mechanical behaviour and residual stresses on the component behaviour are investigated. The simulation results for local microstructure and mechanical behaviour are compared to experimental results, and the predicted local mechanical behaviour is incorporated on an element level into the FEM simulation. The numerical effect of the variations in mechanical behaviour is quantified by comparing the results achieved using local behaviour and homogeneous behaviour. The influence of residual stresses predicted by the casting process simulation on the component behaviour is also studied.

    The casting process simulation is found to accurately predict the local variations in microstructure throughout the component, and the local variations in mechanical behaviour are well described. The numerical results show that casting process simulation and modelling of microstructure formation, material behaviour and residual stresses are important contributions to correctly predict the behaviour of a cast aluminium component in service. This motivates the use of the proposed simulation strategy, and show the importance of incorporating materials science and casting process simulations into structural analyses of cast components. It is discussed that integration of these areas, e.g. using the closed chain of simulations, is important in order to increase the accuracy of FEM simulations and the product development efficiency in the future.

  • 30.
    Olofsson, Jakob
    et al.
    Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Svensson, Ingvar L.
    Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Lava, Pascal
    Department MTM, KU Leuven, Belgium.
    Debruyne, Dimitri
    Department MTM, KU Leuven, Belgium.
    Characterisation and investigation of local variations in mechanical behaviour in cast aluminium using gradient solidification, Digital Image Correlation and finite element simulation2014In: Materials & Design, ISSN 0261-3069, Vol. 56, p. 755-762Article in journal (Refereed)
    Abstract [en]

    Due to design and process-related factors, there are local variations in the microstructure and mechanical behaviour of cast components. This work establishes a Digital Image Correlation (DIC) based method for characterisation and investigation of the effects of such local variations on the behaviour of a high pressure, die cast (HPDC) aluminium alloy. Plastic behaviour is studied using gradient solidified samples and characterisation models for the parameters of the Hollomon equation are developed, based on microstructural refinement. Samples with controlled microstructural variations are produced and the observed DIC strain field is compared with Finite Element Method (FEM) simulation results. The results show that the DIC based method can be applied to characterise local mechanical behaviour with high accuracy. The microstructural variations are observed to cause a redistribution of strain during tensile loading. This redistribution of strain can be predicted in the FEM simulation by incorporating local mechanical behaviour using the developed characterization model. A homogeneous FEM simulation is unable to predict the observed behaviour. The results motivate the application of a previously proposed simulation strategy, which is able to predict and incorporate local variations in mechanical behaviour into FEM simulations already in the design process for cast components.

  • 31.
    Omerovic, Semir
    Jönköping University, School of Engineering, JTH, Industrial Product Development, Production and Design.
    Utveckling av häftpistol R4532019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 32.
    Pakkam Gabriel, Vivek Richards
    Jönköping University, School of Engineering, JTH, Materials and Manufacturing.
    FATIGUE MODEL: Stiffness prediction of damaged laminates based on the concept of damaged layers' effective stiffness2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Despite composite materials are widely used in many applications, prediction on damage mechanism of the composite materials is still very difficult. Using the findings from the research on damage mechanism under fatigue loading, its transverse cracking and its crack opening and sliding displacement, a mathematical model has been developed. The model showed results closer to the real-time experimental results in crack initiation and growth. The aim of the thesis is to develop a computational tool using the mathematical model and effective stiffness concept of the layers with cracks to predict the degradation of the longitudinal young’s modulus and shear modulus of the composite laminate. In addition to that, graphical user interface is also created making the user control the tool easily. The tool developed shows promising results but still lacks the information on the effects of delamination on crack opening displacement and effective shear modulus.

  • 33.
    Pettersson, Jens
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Larsson, Tom
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Utvecklingsarbete av avfallspress2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis a further development of Orwak AB’s existing product, TOM, has been developed. The product is a trash bin that compresses the waste the user dumps to reduce the volume of the trash. A machine like this is called a waste compactor. The problems which had been revealed was that the user could not toss the waste during the compression process and the existing compression system was not optimally designed.The project started with a requirement specification that was made together with the company to create clear guidelines about what should be done. A GANTT-schedule was also made to know what and when everything was going to be performed. The work then proceeded with a pilot study, followed by a method called Brainstorming that is used to develop new ideas. The concepts was then screened through both feedback from the company and a method called Pughs matrix. Finally, only a few concepts remained and was further developed in the 3D-modelling program Solid Works.The final result became a new compression system and a new type of disposal hatch. The new compression system is driven by an electrical actuator that is connected to one of the arms in the so called “scissor lift solution”. By using this type of solution, the compression system became more compact and at the same time reduced the compression time due to the high gearing. The new disposal hatch looks like a type of garage door and occupies less space inside the machine. The hatch also has a magnetic switch that offers a safe solution to toss waste during the compression process.The project has only developed concept solutions in CAD that can be further developed by the company. No calculations or tests has been done on the concepts due to the limited time frame and an agreement with the company.

  • 34.
    Rashid, Asim
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    An Efficient Sequential Approach for Simulation of Thermal Stresses in Disc Brakes2012In: Nordtrib 2012, 15th Nordic Symposium on Tribology, 2012, 2012Conference paper (Other academic)
    Abstract [en]

    In this paper an efficient approach to simulate thermal stresses due to frictional heating of disc brakes is presented. Inthe approach thermal and stress analysis are performed sequentially. The frictional heat analysis is based on the Eulerianmethod, which requires significantly low computational time as compared to the Lagrangian approach. Completethree-dimensional geometries of a disc and a pad are considered for the numerical simulations. The contact forcesare computed at each time step taking the thermal deformations of the disc into account. The nodal temperaturehistory is recorded at each time step and is used in sequentially coupled stress analysis, where a temperature dependentelasto-plastic material model is used to compute the stresses in a disc brake. The results show that during hard braking,high compressive stresses are generated on the disc surface in circumferential direction which cause plastic yielding. Butwhen the disc cools down, the compressive stresses transform to tensile stresses. Such thermoplastic stress history maycause cracks on disc surface after a few braking cycles. These results are in agreement with experimental observationsavailable in the literature.

  • 35.
    Rashid, Asim
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Sequential simulation of thermal stresses in disc brakes for repeated braking2013In: Proceedings of the Institution of mechanical engineers. Part J, journal of engineering tribology, ISSN 1350-6501, E-ISSN 2041-305X, Vol. 227, no 8, p. 919-929Article in journal (Refereed)
    Abstract [en]

    In this paper, an efficient sequential approach for simulating thermal stresses in brake discs for repeated braking is presented. First, a frictional heat analysis is performed by using an Eulerian formulation of the disc. Then, by using the temperature history from the first step of the sequence, a plasticity analysis with temperature dependent material data is performed in order to determine the corresponding thermal stresses. Three-dimensional geometries of a disc and a pad to a heavy truck are considered in the numerical simulations. The contact forces are computed at each time step taking the thermal deformations of the disc and pad into account. In such manner, the frictional heat power distribution will also be updated in each time step, which in turn will influence the development of heat bands. The plasticity model is taken to be the von Mises yield criterion with linear kinematic hardening, where both the hardening and the yield limit are temperature dependent. The results show that during hard braking, high compressive stresses are generated on the disc surface in the circumferential direction which cause yielding. But when the disc cools down, these compressive stresses transform to tensile residual stresses. For repeated hard braking when this kind of stress history is repeated, we also show that stress cycles with high amplitudes are developed which might generate low cycle fatigue cracks after a few braking cycles.

  • 36.
    Rashid, Asim
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Thermomechanical Simulation of Wear and Hot Bands in a Disc Brake by Adopting an Eulerian Approach2013In: Eurobrake 2013, 2013Conference paper (Refereed)
    Abstract [en]

    In this paper frictional heating of a disc brake is simulated while taking wear into account. By performing thermomechanical finite element analysis, it is studied how the wear history will influence the development of hot bands. The frictional heat analysis is based on an Eulerian formulation of the disc, which requires significantly lower computational time as compared to a standard Lagrangian approach. A real disc-pad system to a heavy truck is considered, where complete three-dimensional geometries of the ventilated disc and pad are used in the simulations. A sequential approach is adopted, where the contact forces are computed at each time step taking the wear and thermal deformations of the mating parts into account. After each brake cycle, the wear profile of the pad is updated and used in subsequent analysis. The results show that when wear is considered, different distributions of the temperature on disc are obtained for each new brake cycle. After a few braking cycles two hot bands appear on the disc surface instead of only one. These results are in agreement with experimental observations.

  • 37.
    Rath Olsen, Christoffer
    et al.
    Jönköping University, School of Engineering, JTH, Industrial Product Development, Production and Design.
    Olsson, Kaspar
    Jönköping University, School of Engineering, JTH, Industrial Product Development, Production and Design.
    Konstruktion av plattform, montering och drivning av höghastighetskameror2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 38.
    Salomonsson, Kent
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization. Jönköping University, School of Engineering, JTH, Product Development.
    Zhao, Xuefang
    Jönköping University, School of Engineering, JTH, Product Development.
    Kallin, Sara
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Rehabilitation. Jönköping University, School of Engineering, JTH, Product Development.
    Analysis of the Internal Mechanical Conditions in the Lower Limb Due to External Loads2016In: World Academy of Science, Engineering and Technology, International Science Index, International Journal of Medical, Health, Biomedical, Bioengineering and Pharmaceutical Engineering, London, 2016, p. 288-293Conference paper (Refereed)
    Abstract [en]

    Human soft tissue is loaded and deformed by any activity, an effect known as a stress-strain relationship, and is often described by a load and tissue elongation curve. Several advances have been made in the fields of biology and mechanics of soft human tissue. However, there is limited information available on in vivo tissue mechanical characteristics and behavior. Confident mechanical properties of human soft tissue cannot be extrapolated from e.g. animal testing. Thus, there is need for non invasive methods to analyze mechanical characteristics of soft human tissue. In the present study, the internal mechanical conditions of the lower limb, which is subject to an external load, is studied by use of the finite element method. A detailed finite element model of the lower limb is made possible by use of MRI scans. Skin, fat, bones, fascia and muscles are represented separately and the material properties for them are obtained from literature. Previous studies have been shown to address macroscopic deformation features, e.g. indentation depth, to a large extent. However, the detail in which the internal anatomical features have been modeled does not reveal the critical internal strains that may induce hypoxia and/or eventual tissue damage. The results of the present study reveals that lumped material models, i.e. averaging of the material properties for the different constituents, does not capture regions of critical strains in contrast to more detailed models.

  • 39.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    An Eulerian approach for simulating frictional heat bands in rotating discs2012Conference paper (Other academic)
  • 40.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    An Eulerian Approach for Simulating Frictional Heating in Disc-Pad Systems2011In: European journal of mechanics. A, Solids, ISSN 0997-7538, E-ISSN 1873-7285, Vol. 30, no 5, p. 673-683Article in journal (Refereed)
    Abstract [en]

    Thermal stresses as a result from frictional heating must be considered when designing disc brakes, clutches or other rotating machine components with sliding contact conditions. The rotational symmetry of the disc in these kind of applications makes it possible to model these systems using an Eulerian approach instead of a Lagrangian framework. In this paper such an approach is developed and implemented. The disc is formulated in an Eulerian frame where the convective terms are defined by the angular velocity. By utilizing the Eulerian framework, a node-to-node formulation of the contact interface is obtained, producing most accurate frictional heat power solutions. The energy balance of the interface is postulated by introducing an interfacial temperature. Both frictional power and contact conductances are included in this energy balance. The contact problem is solved by a non-smooth Newton method. By adopting the augmented Lagrangian approach, this is done by rewriting Signorini’s contact conditions to an equivalent semi-smooth equation. The heat transfer in the disc is discretized by a Petrov–Galerkin approach, i.e. the numerical difficulties due to the non-symmetric convective matrix appearing in a pure Galerkin discretization is treated by following the streamline-upwind approach. In such manner a stabilization is obtained by adding artificial conduction along the streamlines. For each time step the thermo-elastic contact problem is first solved for the temperature field from the previous time step. Then, the heat transfer problem is solved for the corresponding frictional power. In such manner a temperature history is obtained sequentially via the trapezoidal rule. In particular the parameter is set such that both the Crank–Nicolson and the Galerkin methods are utilized. The method seems very promising. This is demonstrated by solving a two-dimensional benchmark as well as a real disc brake system in three dimensions.

  • 41.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Development and Implementation of an Eulerian Approach for Efficient Simulation of Frictional Heating in Sliding Contacts2011In: Coupled problems 2011 : computational methods for coupled problems in science and engineering IV: proceedings of the IV International Conference on Computational Methods for Coupled Problems in Science and Engineering held in Kos, Greece, 20 - 22 June 2011, 2011Conference paper (Refereed)
  • 42.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    RBDO with Non-Gaussian Variables by using a LHS- and SORM-based SLP approach and Optimal Regression Models2012Conference paper (Other academic)
    Abstract [en]

    A general sequential linear programming (SLP) approach for reliability based design optimization (RBDO) with non-Gaussian random variables is presented. The RBDO problems are formulated by using optimal regression models (ORM) as surrogate models and S-optimal design of experiments (DoE). The S-optimal DoE is obtained by maximizing the average mean of the distances between the nearest neighbors. Finite element simulations are performed for the S-optimal DoE and corresponding ORM are obtained by a genetic algorithm. In such manner not only optimal regression coefficients are generated but also optimal rational base functions. The RBDO problems are solved by introducing intermediate variables defined by the iso-probabilistic transformation at the most probable point. By using these variables in the Taylor expansions, a corresponding deterministic linear programming problem is derived, which is corrected by applying second order reliability methods (SORM) as well as Monte Carlo simulations. For low target values on the reliability crude Monte Carlo simulations are used, but for high targets a Latin hypercube sampling (LHS) approach is utilized. The implementation of the suggested sampling- and SORM-based SLP approach is efficient and robust. This is demonstrated by presenting trade-off curves between the objective function, constraints, variables and the target of reliability.

  • 43.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Simulering av bromsvärme i en skivbroms med en Eulerformulering, Svenska Mekanikdagar2011Conference paper (Other academic)
  • 44.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Topology Optimization of Bodies in Unilateral Contact by Maximizing the Potential Energy2012In: Proceedings the Eleventh International Conferenceon Computational Structures Technology / [ed] B.H.V. Topping, Civil-Comp Press , 2012, p. Paper 237-Conference paper (Refereed)
    Abstract [en]

    The modelling of the boundary conditions is crucial in topology optimisation. Small changes in these conditions will typically imply new optimal layouts of material. In many situations the design domain is connected to an assembly of components using contact interfaces. In order to generate proper layouts for this type of design domain one must treat these contact interfaces accurately in the topology optimisation procedure.

    The bottle-neck in topology optimisation of non-linear structural problems, such as contact problems, is to solve the state equations and the adjoint equations. By choosing the potential energy as the objective the latter equations are not needed in the sensitivity analysis. In this paper topology optimization of contact problems including non-zero prescribed displacements by maximizing the potential energy is performed. For contact problems with zero initial contact gaps and zero prescribed displacements this is equivalent to minimising the compliance, which is the standard approach in topology optimisation. However, when the compliance is used as objective in topology optimisation of contact problems an extra adjoint equation must be solved. This is not needed in the formulation presented in this paper.

    The efficiency of the approach is demonstrated by studying three different problems, two problems in two-dimensions and one in a three-dimensional setting. The method is implemented by using Matlab and Intel Fortran, where the Fortran code is linked to Matlab as mex-files. The implementation can be downloaded as a toolbox (Topo4abq). The three problems have beensolved using this toolbox on a laptop with an Intel Core i7 2.67 GHz processor and a 64 bit version of Windows. It is shown that the CPU-time is reduced as much as 25% compared to an adjoint approach developed in previous works.

  • 45.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Topology Optimization of Hyperelastic Bodies by Maximizing the Equilibrium Potential Energy2012Conference paper (Other academic)
  • 46.
    Strömberg, Niclas
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Tapankov, Martin
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Development of a successive response surface approach for reliability-based design optimization2011Conference paper (Other academic)
  • 47.
    Söderlund Valencia, Lorens
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    PARAMETRISERAD DESIGN APPLICERAD PÅ EN MOTORSÅGSKEDJA2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main objective of this thesis was to develop appropriate strategies and find factors that affect the usability of parameterized designs. This was accomplished by investigate the user-interface and how it is designed to meet the user's information needs. The thesis also embraces the basic theories in terms of investigation, cognitive design principles and human behavior patterns in the interaction with the machine. The approach has led to an explorative investigation in this subject area.

    The thesis also had the purpose to achieve more efficient ways for development of motor chainsaws at Husqvarna AB's department Global Cutting Equipment. That can be achieved through reduce costs of development per sold unit. To reduce cost depends to what extend the program is helping the user to achieve goals during the design execution. The thesis also includes an investigation of the factors that affect the design of such a program. To explore appropriate strategies was a theoretical design process implemented in the study. From the perspective of technology has the author utilized knowledge in engineering design and programming. The program approach utilized was Visual Basic languish in Visual Studio enviroment for the user-interface and a Catia V5 CAD-platform for the chainsaw design.

    The result is a program which could use reconfigured parameters as needed to create customized designs correctly and effectively. This thesis has also resulted in appropriate principles for the design of a user-friendly interface that were up for the task to be a supporting tool through the execution. It has also been established appropriate tools and methods for analysis and optimization of the program. The author feels that the results of methods and principles in this study were of high reliability and can therefore be applied to other projects, even if the results only are valid for this specific case.

  • 48.
    Tao, Jiyue
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Aziz, Asnaf
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Simulation of thermal stresses in a disc brake2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The heat flux produced from the friction between a disc and pad system leads to a high temperature which causes thermal stresses in the disc and after a number of repeated braking cycles, cracks might be initiated. The finite element analysis (FEA) is performed to determine the temperatures profile in the disc and to analyze the stresses for the repeated braking, which could be used to calculate the fatigue life of a disc.Sequentially coupled approach is used for thermo-mechanical problem and the problem is divided into two parts, heat analysis and thermal stress analysis. The heat analysis is obtained by including frictional heat and adopting an Eulerian approach. The heat analysis is conducted by using Abaqus and the toolbox developed by Niclas Strömberg. The thermal stress analysis, which is the main focus of this thesis, is followed using Abaqus. The plasticity theory as background for stress analysis is discussed in detail. The rate independent elasto-plastic plasticity is used in the stress analysis. Temperature independent material properties are considered throughout the thesis work.Isotropic, kinematic and combined hardening models are analyzed for simple 2D academic models for different types of cyclic loads. A benchmark disc and pad model, which is less complicated than the real disc-pad model, is also studied. The linear kinematic hardening model with rate independent elastic-plastic plasticity is used for benchmark and real disc-pad model. The results of the benchmark model and the real model are observed to be similar in terms of plasticity theory.

  • 49.
    Tapankov, Martin
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Reliability Design in Structural Optimization - Literature Survey2013Report (Other academic)
    Abstract [en]

    This survey focuses primarily on the historical development of RBDO and the various classes of methods which emerged through the years. While reviews on contemporary RBDO methods have been done previously, they haven’t incorporated the basis on which such developments were possible in the first place — risk-based design and limit-state design. This study attempts to link the RBDO field with these methodologies for a more complete picture of the field of reliability and safety.

  • 50.
    Tapankov, Martin
    et al.
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Sampling- and SORM-based RBDO of a Knuckle Component by using Optimal Regression Models2012In: the proceedings of the 14th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, American Institute of Aeronautics and Astronautics, 2012Conference paper (Refereed)
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