Nowadays, the use of robots in industrial tasks is growing constantly. However, manual assembly is one area that is hard to make fully automated since manual assembly operations work with different shapes and products that require human finesse to do some operations. Humans, on the other hand, have a lot of limitations since this kind of task can be unergonomic and repetitive for operators, which can cause them stress, fatigue, repetitive stress injuries(RSI), and repetitive motion injuries. This project involved designing an insert for the gripper 2F-85 (version 3) that would allow the collaborative robot (UR5) to carry out more assembly tasks in order to relieve human workers of repetitive tasks. The insert has to handle cylindrical shapes in addition to bigger parts that the actual insert cannot handle due to its parallel stroke. For that, a detailed market analysis and insert research were conducted in the initial study. The new insert was then developed using a double-diamond design process. The needs were ranked using the Moscow prioritization method, and ideas were then generated using the brainstorming technique. The final concept was chosen using the weighted decision matrix method. After the final concept selection, computer-aided design (CAD) technology was employed to create the new insert's 3D model and its technical specifications. The mechanical behaviour of the new insert was analysed to reflect its range of workability, expressing the maximum force that it can withstand on each of its grip work surfaces without presenting plastic deformation. For this study, finite element analyses were conducted following the general method for linear structural analysis using Abaqus. Achieving an insert that can reach, transport, and assemble different shapes will help integrate collaborative robots into manual assembly processes, avoiding the cost of a new gripper.

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As rail transportation is significantly more virtuous than airplanes or cars in terms of greenhousegases emissions, its development is being encouraged in several European countries, includingSweden. In addition, the development of railway lines on which trains can travel at higher speeds ismade in Sweden with the integration of existing infrastructure. On railway bridges, an increased trainspeed potentially leads to an increase in vibrations during passage, for which the structure may not bedesigned. It is therefore essential to know the dynamic properties of the structures used.Several studies highlight the influence of friction phenomena in sliding bearings on the dynamicproperties of bridges equipped with them. This Master Thesis is based on previous works that led tothe development of a finite element modelling the friction mechanisms that occur in these bearings.The friction occurring between a PTFE sliding plate and a steel surface is thus modelled using the Bouc-Wen model, a model for hysteresis phenomena. The finite element was developed as a Fortransubroutine, which can be integrated into the finite element calculation software Abaqus as a "userdefinedelement". It allows friction to be modelled along the longitudinal direction of the bridge onlyand can therefore only be used in two-dimensional models. The user-defined element is also based ona model that takes into account the influence of contact pressure and sliding velocity on the steel-PTFEcoefficient of friction. As several studies indicate, contact temperature can also have a significantinfluence on the value of the coefficient of friction but is not taken into account in the current model.In this project, the previously developed finite element was therefore generalized to account forfriction in both directions of the sliding plate by the means of a two-dimensional generalization of theBouc-Wen model. Based on experimental data available in scientific literature, the model forcalculating the coefficient of friction was also extended to take into account the influence of thecontact temperature. In addition, a model to update the contact temperature based on the theory ofsurface heating of semi-infinite bodies has been incorporated. Finally, this thesis presents theintegration of this updated finite element on three-dimensional models of the Banafjäl Bridge, locatedin northern Sweden. Simulations to estimate the fundamental frequencies and resonance modes ofthe structure as well as the temperature increase that can occur in a bearing during the passage of atrain were carried out on this model.

This paper presents a numerical investigation into the behaviour of headed shear stud in composite beams with profiled metal decking. A three-dimensional finite element model was developed using general purpose finite element program ABAQUS to study the behaviour of through-deck welded shear stud in the composite slabs with trapezoidal deck ribs oriented perpendicular to the beam. Both static and dynamic procedures were investigated using Drucker Prager model and Concrete Damaged Plasticity model respectively. In the dynamic procedure using ABAQUS/Explicit, the push test specimens were loaded slowly to eliminate significant inertia effects to obtain a static solution. The capacity of shear connector, load-slip behaviour and failure modes were predicted and validated against experimental results. The delamination of the profiled decking from concrete slab was captured in the numerical analysis which was observed in the experiments. ABAQUS/Explicit was found to be particularly suitable for modelling post-failure behaviour and the contact interaction between profiled decking and concrete slabs. It is concluded that this model represents the true behaviour of the headed shear stud in composite beams with profiled decking in terms of the shear connection capacity, load-slip behaviour and failure modes.

Total ankle replacement (TAR) implants are an effective option to restore the range of motion of the ankle joint for arthritic patients. An effective tool for analyzing these implants’ mechanical performance and longevity in-silico is finite element analysis (FEA). ABAQUS FEA was used to statically analyze the von Mises stress and contact pressure on the articulating surface of the bearing component in two newly installed fixed-bearing total ankle replacement implants (the Wright Medical INBONE II and the Exactech Vantage). This bearing component rotates on the talar component to induce primary ankle joint motion of plantarflexion and dorsiflexion. The stress response was analyzed on this bearing component since it is made of the least strong material in the implant assembly (ultra-high molecular weight polyethylene (UHMWPE). This bearing component commonly fails and is the cause for surgeon revisions. Six different FEA models for various gait percentages during stance (10%, 20%, 30%, 40%, 50%, and 60%) were created. They varied in magnitude of the compressive load and the ankle dorsiflexion/plantarflexion angle. This study captured the variation in stress magnitudes based on the portion of the stance phase. The results indicated that the stress distribution on the articulating surface increased as compressive load increased, and the largest magnitudes occurred at high dorsiflexion angles (15-30°). The von Mises stress and contact pressure tended to occur in regions where the thickness of the bearing was the least. Additionally, high contact pressures were examined in areas near the talar component's edge or at the bearing's edges. To the author’s knowledge, this is the first study available to the research community that analyzes the Vantage implant with FEA. This study lays an essential foundation for future researchers in presenting a thorough literature review of TAR and for a simple model setup to capture the stress distributions of two TAR implants. This study provides valuable information that can be beneficial to medical company designers and orthopedic surgeons in understanding the stress response of TAR patients.

Protection of buried pipes is a serious issue that concerns countries around the world. Therefore, there is a need for new soil improvement techniques such as geosynthetic materials installation to protect these pipes from damage. This study used large-scale laboratory tests to study the behaviour of buried pipes. A total of 22 large-scale tests were performed to study the behaviour of buried flexible HDPE pipes with and without void presence under the protection of the geogrid reinforcing layers subjected to incrementally increasing cyclic loading. The presence of voids located at the spring-line of the flexible buried pipes, led to a considerable increase in the soil surface settlement, pressure recorded at the pipe crown, spring-line and invert, pipe deformation and strain recorded in the pipe wall. Increasing the pipe burial depth contributed to significant reductions in the soil surface settlement, pressure recorded at the pipe crown and invert, pipe deformation and strain recorded in the pipe wall. However, the void presence limited the contribution of increasing the pipe burial depth. The inclusion of a geogrid reinforcing layer contributed to a considerable reduction in the soil surface settlement, pressure recorded at the pipe crown, spring-line and invert, pipe deformation and strain recorded in the pipe wall. The use of a combination of geogrid reinforcing layers and increasing the pipe burial depth contributed in diminishing the ground void presence effect, where better pressure distribution inside the system was achieved. Consequently, more protection was provided to the buried pipe.