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Analyzing early-stage production through discrete event simulation: A Case study at Magna Electronics Developing a simulation model to analyze the performance of a production line and evaluating its ability for decision making at an early stage
(2026) Andersson, Elias; Säll-Magnusson, Noah
The highly competitive automotive industry, characterized with varying customer demands and requirements puts pressure on manufacturing organization’s ability to develop flexible and efficient production systems, particularity its early stage. Magna Electronics Vårgårda production system is currently expanding and under constant development through the implementation of new production lines. Therefore, there is a need to understand how system parameters effect performance of the production line in its early stage of development. Hence, the aim of this study is to investigate and analyze the newly implemented production line CHA1 through the development of a discrete event simulation (DES) model. More specifically, understand how DES can be used as a decision-making tool, evaluate the influence of overall equipment effectiveness and direct labor cost as well as highlighting the challenges in this context. The methodology of the study is based on the first nine stages of Banks simulation framework, which were divided into three phases. Within this framework, a literature review was conducted in combination with a mixed method approach. The qualitative data collection provided in-depth understanding of the production line through the combination of interviews, observations and informal conversations. Whereas the quantitative data were collected through shop floor measurement and from the company database, essential for input modeling and the development of the DES model. The experiments conducted through the DES model and the corresponding findings showed that DES can be a useful tool to enhance decision making and evaluate performance in an early stage of production. However, the early stage contributed to several challenges regarding input data collection and a higher degree of simplifications and estimations, effecting the ability to develop a model with the highest possible accuracy.
Utveckling av antenn för elektromagnetisk ultraljudstomografi
(2026) Amin, Robin; Barrdahl Morad, Neo; Camacho Stjernlöf, Sofia; Grankull, Alva; Larsson, Sara; Werner, Isaac
Detta arbete syftar till att utveckla ett proof-of-concept for den elektromagnetiska delen av ett kombinerat elektromagnetiskt och ultraljudsbaserat (EM/US) tomografisystem for smådjursavbildning. I preklinisk forskning anvands smådjur, såsom möss, för att studera tumörutveckling och utvärdera nya behandlingsmetoder. Ickeinvasiva avbildningsmetoder kan avsevärt minska antalet djur som behövs i dessa undersökningar. Arbetet omfattar utveckling och utvärdering av två antenntyper, en smalbandig patchantenn och en bredbandig Vivaldiantenn, med målet att kunna integrera den antenn som ger bäst resultat i ett antennsystem. For att testa antennernas prestanda analyserades deras spridnings- och transmissionskoefficienter samt deras penetrationsdjup i vävnad. Simuleringarna genomfördes i CST Microwave Studio med olika fantomtyper avsedda att efterlikna smådjursvavnad. For patchantennen utfördes även VNA-matningar for att experimentellt verifiera simuleringarna. Simuleringarna visade att patchantennen uppnådde en god matchning vid 1,45 GHz, medan Vivaldiantennen gav bredare bandbredd och djupare signalpenetration i fantomer. Båda antennerna uppvisade dessutom reflektionskoefficienter under -10 dB vid önskad frekvens och genererade transmissionsnivåer som möjliggör vidare analys i ett tomografisystem. VNA-mätningarna för patchantennen visade tydliga likheter med simuleringarna. De verkliga och simulerade patchantennerna resonerade vid ungefär samma frekvens och hade dessutom en liknande bandbredd. Baserat på resultaten bedömdes patchantennen vara mest lämplig för integration i EM/US-systemet.
Detailed Nonlinear Analysis of Bolted Joint
(2026) Shrikant Damle, Deepashri
Bolted joints are widely used in industrial applications due to their strength and ease of assembly. The most important characteristic of a bolted joint is its ability to prevent sliding motion between the joint parts when subjected to vibrations as well as external loading, by exerting a compressive force on the joint members. The clamping force generated during the assembly process is a function of various factors like the applied torque, material of the joint, behaviour of contact interfaces, as well as external conditions such as temperature. This project aims to understand the behaviour of a bolted joint during the assembly process with an applied torque. The finite element method is used to analyse the interaction between different components of a bolted assembly during its tightening process. A detailed 3D model is implemented in the finite element software ABAQUS. Torque is applied and then removed to simulate the tightening and torque tool removal. How friction affects this process is studied by varying the friction coefficient at the under-head interface. Results obtained from finite element analysis show agreement with commonly used handbook calculations for bolted joints. Varying under-head friction shows that the bolt preload does not drop significantly during torque removal; however, the friction under the head is found to affect the rate of preload drop after assembly. The analysis presented in this study can be further adapted to study the effect of other factors, like material properties, loading rate during tightening, as well as the response under external loads
Toward Stabilization of the Quantum Pair-Cat State on Superconducting Circuits Platform
(2026) Jesper, Lagerberg
In this thesis, we introduce a quantum circuit for stabilizing an error-correctable two-mode quantum cat state, known as the pair-cat state. Using Foster decomposition, we derive experimentally feasible circuit parameters that engineer a dominant fifth-order flux nonlinearity, yielding the effective Hamiltonian required for pair-cat state generation. We further present implementations of logical X rotations, show casing the possibility of rotating around the Bloch sphere and encoding quantum information.
Koordinering av drönare för autonom områdesavsökning
(2026) Ahmad, Hassan; Edling, Alma; Larsson, Oscar; Sellin Bredberg, Ninus; Skoglund, Jesper
This study investigates how drones of the model Crazyflie2.1+, in combination with a motion capture system, can be used for autonomous area scanning and, upon detection, tracking and streaming of the positional data of a moving target. To enable a drone system capable of autonomously switching between area scanning and target tracking, a control script was developed utilizing Qualisys track manager and Crazyswarm2. The results show that the drones were able to follow a predefined search trajectory and, upon detection of a moving target, transition to target tracking while constantly streaming its position to an external system. However, the transition to area scanning after tracking was not implemented due to time constraints. This study demonstrates the potential of motion capture-based drone systems for autonomous navigation and target tracking in controlled environments, while also highlighting challenges related to the implementation of such systems.