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Flower: A Visualization Tool for Reflecting on Smartphone Use
No full textThis thesis explores the design considerations for creating a tool that encourages meaningful reflection on smartphone use. To investigate this, an app called Flower was developed, allowing users to categorize each app session and then view visualizations of their usage. Two visualization styles were tested; a conventional bar chart and a more novel "flower field" where each flower represented an app session. Over an eight-day user study with twelve university students, findings indicated that the act of self-categorization prompted greater reflection and that users felt the visualized data better represented their experiences. While most participants preferred the flower field for its aesthetics and exploratory nature, some valued the bar chart for its clarity and ease of interpretation.
The study suggests that encouraging users to reflect on their smartphone use in context, rather than labeling all screen time as negative can motivate users to explore their data, and draw more meaningful insights about their phone use. Novel visualizations can increase user interest, though care must be taken to balance abstractness with clarity. Limitations of the study include minor technical issues and a small, homogeneous participant group. Future research could explore more personalized visualizations, longer-term use, and broader participant samples.
This work contributes to understanding how creative, user-driven tools can foster reflection and more nuanced perceptions of digital well-being
Klimatförändringar och dess effekter på stabiliteten för naturliga slänter - En analys av klimatförändringarnas potentiella påverkan på två slänter längs Göta älv
No full textDetta kandidatarbete undersöker hur förväntade klimatförändringar påverkar
stabiliteten hos två representativa slänter i Östra Berg, längs Göta älv där
kvicklera förekommer. Genom numerisk stabilitetsmodellering i GeoStudio
2024 med modulerna SLOPE/W och SEEP/W analyseras scenarier med ökad
nederbörd och successiv erosion vid släntfoten. Resultaten visar att klimatpåverade
förhållanden avsevärt försvagar de redan skredkänsliga slänterna, speciellt när
intensiv nederbörd samverkar med erosion. Slutsatsen är att det finns ett behov av
att i större omfattning inkludera den påverkan klimatförändringar har i framtida
stabilitetsutredningar. Risken för skred kan underskattas om skredriskutredningar
enbart utgår från dagens klimat. En ökad kunskap, både kring faktorernas enskilda
inverkan och dess samverkan, krävs för att på ett effektivt och precist sätt kunna
minimera risken för framtida skred i området
Design of a Solution for Blind Assembly of Bolts - Assembly of Low-visibility Bumper Bolts with a Focus on Ergonomics and Safety
No full textThis project focuses on the assembly of low-visibility bumper bolts under the truck model known as the Volvo FML- a process currently not possible on the assembly line due to challenging posture
and safety hazards. The project seeks to solve these challenges and ultimately allow Volvo Trucks in Tuve to shift this assembly from an after-line area where it is done presently, to the main line.
A linear product development methodology has been used with iterative test-design-build cycles inspired by lean principles. This was chosen over a more flexible, agile methodology to make it easier to
coordinate activities with Volvo. A thorough pre-study was conducted to lay the theoretical groundwork for the project, which included both researching existing solutions to similar problems, and a detailed
study of the current state. The current state analysis was then used to add detail to the problem statement. Key stakeholders were identified and continually contacted throughout the project to ensure
the fulfilment of their interests in the project’s outcome. Concept generation was conducted, which yielded 14 unique concepts in different phases of the project, while keeping the solution space as open
as possible. Importance was placed on thoroughly documenting concept generation for Volvo’s future reference. Selection and elimination matrices were used to refine or identify the best performing
concepts in the initial stages, which yielded 3 concepts to prototype. The 3 prototypes were developed, and further elimination to obtain the winning concept was conducted at the last possible stage,
only when feasibility or suitability was deemed impossible.
User testing and verification was conducted, which revealed the winning concept and resulted in 4 design changes to it. Well-researched ergonomics and safety testing methodologies were employed to
verify suitability of the suggested solution. The final solution was tested on the moving assembly line, on the Volvo FML. One crucial trade-off was made, in the interest of ease of maintenance.
Other suitable solutions have been suggested, with clear reasoning behind why they were not developed. The final solution solves the problem that has been proposed by Volvo
Ballistik och aerodynamik av badmintonbollar. En studie av olika typer av badmintonbollars egenskaper kopplade till ballistik och aerodynamik
No full textBadminton är den snabbaste bollsporten i världen, där kraven på spelarnas snabbhet, reflexer och smidighet blir höga. Detta ställer också höga krav på
materialet och tåligheten hos bollarna. Syftet med denna rapport är att beskriva skillnader och likheter mellan några av bollarna som spelas med idag. Detta för att kunna avgöra hur bollarna flyger men också varför de flyger som de gör.
För att studera detta har bollarnas flygbanor filmats och simulerats. Bollarnas olika tröghetsmoment har beräknats och de har även modellerats i CAD.
Viktiga resultat från studien visade att tröghetsmomentet hos badmintonbollar påverkade deras flygbeteende. Ett högre tröghetsmoment, I_xx, (roll axis) resulterade i större spridning i sidled, medan ett högre tröghetsmoment, I_yy, I_zz, minskade tumling.
Vidare indikerade resultaten att även om tröghetsmomenten har tydliga effekter, är de sannolikt inte de enda faktorerna som påverkar bollens flygegenskaper. De aerodynamiska egenskaperna och bollens geometri påverkar också flygbeteendet. Här rekommenderas fortsatt forskning inom området.
Slutligen föreslogs en standardiserad testmetod för badmintonbollar baserad på mätningar av standardavvikelser för exempelvis sidoavvikelse, räckvidd och tumling. Detta skulle möjliggöra en mer praktisk bedömning av bollarnas kvalitet och prestanda. Detta arbete har därmed lagt grunden för en ökad förståelse av hur olika egenskaper hos badmintonbollar påverkar deras flygbeteende och kan bidra till framtida utveckling av bollar med förbättrade flygegenskaper
Modulair-C redesign av kombiaggregat 500 ex
No full textThis bachelor’s thesis was conducted in collaboration with ÅSS Processventilation with the objective of redesigning the central vacuum unit Kombiaggregat 500 EX.
The current model suffers from outdated technology, poor user-friendliness, and a design language not aligning with the vision of the company. The aim of the project
was to develop a modern, energy-efficient, and user-centered product with true Plug & Play functionality. Through pre-studies, user observations, and technical analysis
several design concepts were generated and iteratively refined. The final solution features a maintenance-free cyclone separator, an improved filter system and a digital
user interface. The unit has been redesigned both technically and aesthetically to enable easier installation, improved service ergonomics, and an enhanced user experience. The project also establishes the foundation for ÅSS’s future design language and product strategy
Cab water-leak detection master’s thesis report
No full textWater intrusion in truck cabs is a recurring quality concern, posing risks from user
discomfort to component damage or failure. The current detection method at Volvo
Trucks’ Tuve plant relies on a water-based test that is time-consuming and resourceintensive,
which makes it impractical for 100% testing coverage. This thesis investigates
the feasibility of using waterless, non-destructive, air pressure-based methods
to detect and locate cab leaks as an alternative to the current process. Pressure
decay, together with pressure monitoring were investigated for detecting leaks, and
thermal imaging as well as acoustic imaging were used for leak localization. A structured
development methodology was followed, including requirement mapping, concept
generation, and experimentation on pressure-based detection combined with
thermal and ultrasonic imaging. The detection methods proved infeasible due to
rapid pressure loss and reading overlaps between watertight and non-watertight
cabs. For leak localization, thermal imaging showed limited effectiveness due to
environmental sensitivity and weak thermal contrast as well as cab isolation which
prevented heat from dissipating outwards. In contrast, ultrasonic imaging successfully
identified several leaks with a higher accuracy. However, results were impacted
by noise and surrounding disturbances which caused false positives in certain cases.
Another issue was that of false positive due to harmless air leaks which were captured
as potential water leaks. The study concludes that while no single method
currently met all criteria for reliable implementation, ultrasonic imaging showed the
most potential. Future work should hence focus on refining ultrasonic localization
by addressing the existing issues. Further on, one possibility could be to investigate
the option of automating the process using machine learning to aid in distinguishing
critical water ingress points from harmless airflow paths to enable scalable deployment
in production
The viability of Rust as a real-time system language: A comparative analysis between Rust and C for real-time systems
No full textReal-time systems are used in many crucial applications in our society, for example, airplanes and satellites. These systems need to be secure and reliable since they are often time-crucial and safety-critical. Security in this aspect means that there are no unforeseen crashes or undefined behavior of the system.
Historically, these systems have been created in C due to the performance C can achieve along with the ability to manipulate hardware at a low level. A performantsystem is important to ensure that the system can handle the workload put on it, however, it is not trivial to combine the aspects of performance and security. This is because security often comes at the expense of performance since additional checks are needed. A new emerging language, Rust, tries to solve this problem.
This thesis will extend the work done by Tjäder [1] on the framework RTIC by testing if Rust is viable in a real-time setting. To achieve this aim, real-time applications in both Rust and C are created, which are then run on different hardware. The purpose is to test the applications with metrics such as performance, memory usage, and reaction time for events. This will be used to evaluate the viability of Rust for real-time systems to make them more secure and reliable.
The thesis concludes that although Rust offers security in terms of memory management, Rust can compete with C in aspects such as performance. It all comes down to different tradeoffs, from what is needed in the specific system to be built
Lifting the Load Optimizing Dishwasher Ergonomics Through User-Centered Design
No full textDishwashers are a widely used appliance in modern homes, yet their design has seen limited ergonomic innovation in recent decades. Most models remain standing on the floor, requiring users to bend down repeatedly during loading and unloading dishware, leading to physical strain on the back. This study aims to improve the ergonomics of household dishwashers by developing user-centered design solutions, in collaboration with ASKO.
Through an iterative design process, the project used a range of methods to analyze the current situation regarding dishwasher ergonomics, gathering both numeric and qualitative data. The data was analyzed leading to the identification of pain points and user needs, and then the development of two ergonomic dishwasher solutions. A contemporary concept and a future concept.
The contemporary concept features a built-in scissors lift mechanism in the door, allowing the users to work at an ergonomically optimized height when loading and unloading the dishwasher, where both the upper and lower basket can be reached simultaneously.
The future concept features modular baskets that can be removed and moved to a better work height, such as the countertop, with handles for better grip. This concept is a holistic concept that blurs the line between the dishwasher and kitchen storage by providing the possibility to store the baskets directly in drawers and cupboards.
Both concepts aim to reduce bending, improve posture, and support usability. Ergonomic evaluations indicate improvements compared to ASKOs dishwashers today, with lower strain on the body in critical tasks when using a dishwasher
Tuning behavior-based robotics in mixed reality using unmanned aerial vehicles
No full textThis thesis investigate a behavior-based robotics (BBR) approach for enabling autonomous unmanned aerial vehicle (UAV) navigation and obstacle avoidance in
unknown environments without relying on global maps. The system leverages
lightweight reactive control architectures, finite state machine (FSM) and subsumption architecture, to support real-time decision making based on local sensor feedback.
A hardware-in-the-loop (HIL) framework is employed to safely evaluate controller
performance under realistic conditions. The HIL setup integrates the Crazyflie UAV
platform, lighthouse-based state estimation, simulated sensor inputs, and a modular
software stack based on microservice architecture.
To further enhance navigation efficiently, genetic algorithm (GA) optimization is
applied to tune key controller parameters, including safe distances, tuning angles,
and behavior transition timings. Experimental results demonstrate that both FSMbased and subsumption-based controllers enable robust mapless navigation and effective obstacle avoidance in complex indoor scenarios. The subsumption controller
exhibits superior performance in cluttered environments, while the FSM controller
performs better in open spaces.
The findings highlight the feasibility of behavior-based UAV control in GPS-denied,
mapless indoor settings, and demonstrate the value of modular HIL testing for rapid
prototyping and validation of autonomous navigation strategies
The landscape institute
No full textThis master thesis explores the role of
the landscape as a secondary entity to
total urbanisation. The aim of the
thesis is to explore how we can reimagine
supporting areas, with the ambition
to foster a deeper understanding of
landscapes, urbanisation and people.
The thesis intends to explore how, in
future societal development, we can
oppose the landscape as a prime economic
asset and in contrast to a current
static state, reimagine supply areas as
sites of progress.
Contextualised in Umeå river in northern
Sweden, the thesis conducts a
narrative divided in five phases; background,
site, manifesto, strategies and
The landscape institute. Outlined by a
theoretical framework, this narrative
unfolds a discourse that raises the following
research questions;
How can architecture create conditions
of care for nature in future societal de velopment?
How can a physical space be designed
to communicate, restore and enrich the
landscape, rather than exploit it?
What follows is an investigation where
prototyping serves as a mediator between
the positioning of the thesis, the
manifesto, and the design outcome,
The Landscape Institute. The result is a
project in two senses; an architectural
artefact as well as a campaign.
The landscape institute becomes a
method to frame a need of a site and
empower further questioning of human
positioning in the landscape. The
thesis highlights a future where we collectively
transcend our superiority to
land, and where architecture becomes
a tool for communication, restoration
and enrichment