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Senast publicerade

Hjälpmedel för ergonomisk montering i specialombyggda fordon
(2026) Olofsson, Victor; Kindberg, Victor; Ericsson, Oscar; Hotlmann, Vilgot; Lindgren, Rickard; Betsgren, Anton
This bachelor thesis was conducted with the aim of improving ergonomics and reducing the physical strain experienced by assemblers at Nordic Vehicle Conversion. The project specifically addressed the lifting and installation of passenger seats and stretcher bases during the assembly process. The product development process was carried out iteratively in several phases, based on a framework designed to provide structure without limiting innovation. Continuous refinement through feedback was a central aspect throughout the project. Ultimately, the work resulted in two proposed solutions. The first solution concerns the handling of passenger seats and consists of an electric pallet stacker combined with a specially designed pallet. Together, these enable an efficient and ergonomically sustainable method for lifting and positioning the seats. The second solution consists of a crane system with an associated strap mechanism that enables the precise lifting and placement of stretcher bases. By implementing these solutions, most manual lifting operations within the assembly process can be eliminated, leading to improved ergonomics and a better working environment for the assemblers
Hejlo – barnens egna hemtelefon Konceptframtagning av barntelefon för användning i hemmet
(2026) Bergman, Sonja; Gavelin, Amanda; Gylseth, May; Louise, Arado Lindström; Thörsman, Ida
This project explores the development of a concept for a home-based communication device designed for children aged 5–9 years. It addresses the increasing exposure of children to smartphones and digital media, and the associated challenges related to screen time, well-being, and parental concerns. A user-centered and iterative design process was implemented, combining both qualitative and quantitative methods such as interviews, surveys, observations and user testing. Through these methods user needs and requirements were identified and translated into a design concept. The result is a communication device focused on interaction by voice. This enables children to communicate with selected contacts without an access to the internet or social media. The concept is integrating features of parental control such as a way to verify contacts and regulate time of usage to ensure safety while supporting a childs independence. The project demonstrates that it is possible to design an alternative communication solution that balances simplicity, safety, and usability. This, while meeting the needs of both children and parents.
Simulation Analysis of Ceramic Shell Representation and Process Parameters in IN718 Investment Casting
(2026) Andersson , Joel
This thesis investigates how ceramic shell representation and selected process parameters influence the simulated solidification behaviour and predicted defect tendency of an investment-cast IN718 aerospace component. Casting simulations are used to compare different thermal conditions around the ceramic shell, with focus on temperature history, heat-flux response, filling and solidification behaviour, shell representation and porosity-related defect indicators. The study treats the ceramic shell as part of the thermal system, rather than only as a geometric boundary, since shell thickness and surrounding boundary conditions affect heat extraction, feeding conditions and last-to-freeze regions. The cast material is not varied as an independent parameter. IN718 is treated as the selected alloy system through which the thermal effects of shell representation and process parameters are interpreted. The simulations show that insulation wrapping has a strong influence on the thermal response of the mould and casting system. Among the investigated process parameters, shell preheat temperature has the strongest influence on the evaluated outputs. Higher shell preheat gives preferable porosity indications, while lower shell preheat gives less favourable indications, especially when combined with lower mass flow. The mass-flow-rate variation has a smaller influence, while the enclosure emissivity has negligible influence for the investigated setup. The comparison between constant and non-uniform shell representations shows that shell representation can affect the local thermal response and predicted defect tendency. However, this effect is smaller than the influence of shell preheat temperature. A limited qualitative comparison with available process observations shows some agreement between simulated defect-indicator regions and observed porosity indications, but the comparison is not sufficient for quantitative validation. The results should therefore be interpreted as simulation-based sensitivity trends that support process understanding, rather than as verified predictions of exact casting quality or as a final production specification.
Automatic Classification of LiDAR Point Cloud Data
(2026) Sahoo, Subhajit; Wely, Ivan
Road surveys use laser scanners to create 3D maps of the road and its surroundings, known as point clouds. This research addresses the automatic detection of moving vehicles within these point clouds. Moving vehicles distort the survey while it is being scanned, so Atritec AB, the company conducting these surveys, faced the tedious task of manually removing them from the resulting point clouds. This consequently became a problem of labeling every point in the cloud by category, tackled using machine learning methods that learn this labeling from examples. An end-to-end pipeline was developed around a model called RandLA-Net to carry out this point-by-point labeling, trained on a dataset created by manually annotating Atritec’s point cloud recordings. Moving vehicles were far rarer in the dataset than the background classes, an imbalance that required a training approach able to counterbalance it. This was disproportionately penalizing the model on certain classes to make up for their infrequency. Experiments were also conducted with other datasets in an attempt to supplement the native Atritec AB dataset. However, due to fundamental differences between the datasets, this was not to any avail. Experimenting with different model designs and iteratively adjusting their settings led to a pipeline that reached a score of 0.74 for the moving vehicle class on parts of the dataset the model had never seen before. On this scale, a score of 0 means none of the moving vehicles were correctly identified, while a score of 1 means every one of them was.
Characterizing Superfluid Stiffness in Cuprate Superconductors - Using Coplanar Waveguide Resonators
(2026) Fagrell Alkeskog, Oscar
High Temperature Superconductors (HTS), despite being discovered almost four decades ago, remain an unsolved puzzle that demands innovative approaches and advanced experimental techniques. The fundamental mechanism behind Cooperpair formation is still unknown, posing a major challenge to efforts aimed at increasing the critical temperature. Recently, the observation of superconductivity in Magic-Angle Twisted Bilayer Graphene (MATBG), driven by moiré-physics and flat-band phenomena, has inspired new perspectives on HTS. This connection arises from striking similarities between cuprates and MATBG, both hosting multiple correlated electronic phases, including superconductivity, although MATBG exhibits a much lower critical temperature. The increased density of states in flat bands naturally enhance the pairing critical temperature but simultaneously suppress superfluid stiffness due to the diverging effective mass, hindering superconductivity. However, the quantum metric in multiband systems, such as MATBG, restores finite stiffness, enabling a superconducting state. Analogous moiré-like effects can be induced in HTS thin films via substratedriven superpotentials. For instance, quasi-periodic one-dimensional potentials from nanometer-scale facets on (110) MgO substrates significantly influence ultrathin YBCO films, promoting electronic nematicity, a precursor to flat-band physics. In this thesis, we investigate superfluid stiffness, which is proportional to 1/λ2 (with λ being the London penetration depth) in YBCO films of varying thickness grown on different substrates. Our measurements reveal a pronounced increase in penetration depth for films on (110) MgO compared to LSAT substrates lacking surface nanostructures, indicating flatter electronic bands. These findings support the possibility of engineering band structures in YBCO thin films, paving the way toward tuning critical temperatures to higher values.