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- PostInvestigating the User Experience of Physical and Digital Interfaces in Automotive Design(2020) Morvaridi Farimani, Hossein; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; I.C. MariAnne, Karlsson; Novakazi, FjollëAbstract With the continuous addition of new infotainment and driver assist features, In-Vehicle Infotainment systems (IVIs) are evolving to enhance convenience. However, balancing the system's output (information presentation) and input (vehicle controls) has become a major challenge for automotive companies. To address the complexity and information overload, many have shifted from physical controls to embedded digital touchscreens, raising questions about how far this transition should go. This shift from physical to digital interfaces presents both benefits and drawbacks. On one hand, digital touchscreens can increase driver distraction due to the visual load and eliminate haptic feedback and muscle memory. On the other hand, they offer flexibility and modern aesthetics. The primary research question was: What are the pros and cons of physical and digital interfaces from a user perspective? The secondary question focused on how the context of use (driving vs. non-driving) impacts user experience with each interface type. To explore these questions, this thesis investigated user satisfaction with both physical controls and digital touchscreens. Online user interviews and a literature review were conducted to assess the pros and cons of each interface in different contexts. The findings revealed that no single interface type is universally preferred. Users favored physical controls while driving, due to the haptic feedback and ease of use, but preferred digital interfaces in non-driving situations, due to their modern appeal and functionality. The study also revealed that user preferences varied based on behavior and attitudes, with early adopters perceiving digital interfaces as more trendy, while conservative users viewed physical interfaces as more reliable. These insights led to the development of design guidelines and a hybrid interface concept, blending physical and digital elements. The concept was evaluated and deemed a better solution than existing systems, though some refinements were suggested. The results provide a foundation for balancing physical and digital elements in future IVI designs. The design guidelines, developed from user needs and research findings, aimed to balance the strengths of physical and digital interfaces. These guidelines led to a conceptual UI design that combined physical controls for driving tasks with digital touchscreens for flexibility in non-driving contexts. The hybrid design was evaluated by both original participants and a wider audience, receiving positive feedback as an improvement over current systems. However, some aspects, like balancing ease of use with digital complexity, needed refinement. Overall, the guidelines, impact map, and evaluations represent progress toward more intuitive and user-friendly in-vehicle interfaces
- PostEffect of Al addition on oxidation behavior of Nb-based refractory alloys at elevated temperatures(2024) Zhao, Yufei; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Guo , Sheng; Li, XiaolongImproving gas turbine efficiency is closely linked to reducing global carbon emissions, which requires the development of materials that can operate at ultra-high temperatures. In this thesis, the oxidation behavior of three quaternary Nb-based refractory alloys, Nb-15Hf-5.5W-4Al, Nb-15Hf-5.5W-8Al, Nb-15Hf-5.5W- 12Al (nominal compositions, in at.%) is reported. The alloys were produced by vacuum arc melting, and the oxidation studies were performed at 800℃, 1000℃, and 1200℃ for 1h, 8h, and 24h, respectively, while the phase constitution, microstructure, and composition of oxidation products were analyzed by XRD, SEM, and EDS. Microstructures of three alloys all showed a single-phase bcc structure with a typical dendritic structure, and their Vicker hardness monotonously increased with the increasing Al content. The oxidation products contained different complex oxides including Nb2O5, Hf6Nb2O17, AlNbO4, WO3, and Nb11AlO29. At 800℃, the oxidation behavior was linear, but at higher temperatures, the oxidation behavior was more parabolic. Although oxide layers and transition layers were seen to form in samples after oxidation at 1000℃ and 1200℃, all formed oxide layers were not protective, and consequently, pesting was observed almost in all cases, except the condition of oxidation at 800℃ for 1h. The results showed that adding Al up to 12 at.% helped to improve the oxidation resistance of these Nb-based refractory alloys, but the improvement was still limited and importantly it was not capable of forming a dense and protective oxide layer yet.
- PostIn-Situ Alloying of Fe-Si-Al Soft Magnetic Alloys Using Laser Powder Bed Fusion(2024) Shri Srinivas, Akshay; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Chaudhary, Varun; Chaudhary, VarunImproving efficiency and reducing power losses in electrical machines relies heavily on the development of advanced soft magnetic materials with optimized properties. To address this need, we employed in-situ alloying of 5.4% aluminum and 24.6% iron with Fe-6.5Si using the Laser Powder Bed Fusion (L-PBF) technique. This specific composition was designed to achieve a balanced set of multi-properties, including high saturation magnetization, low coercivity, high resistivity, and superior mechanical strength. The resulting Fe90.05Si4.55Al5.4 alloy was analyzed through various characterization techniques to gain insights into its microstructure, crystal structure, as well as its magnetic and mechanical properties. The analysis revealed a homogeneous alloy with a single-phase body-centered cubic (BCC) structure. Through microstructure analysis, it was found that the metal regions was dense with very few cracks whereas the elemental composition was found to be homogeneous and similar to the nominal composition in these regions. The alloy exhibited a saturation magnetization of 166 emu/g and a coercivity of 4.7 Oe and found to be magnetically stable upto a temperature of 900 K. Additionally, a Vickers hardness of 423 HV was measured, which is significantly higher than that of Fe-3.5Si and Fe-6.5Si.
- PostAn Optimization and Cluster based Approach to Lookup Tables in Design of Adaptive Restraint Systems(2024) Ashok Kumar, Rahul Dasikatte; Anand, Pranav; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Isaksson, Ola; Arjomandi Rad, Mohammad; Wehrmeyer, Lara; Balague, HenrikThe timely deployment of vehicle restraint systems is crucial in mitigating the impact of collisions and protecting occupants in the affected vehicles. The level of protection can be further enhanced with the use of adaptive restraint systems, by adjusting the force and timing of seatbelts and airbags based on factors such as vehicle speed, occupant size, and seating position. Virtual testing methods can help identify areas of improvement of adaptive systems by evaluating its performance across a range of crash scenarios. While finite element simulation models and data-based surrogate models have been used in literature for restraint system development, data structures such as lookup tables containing restraint settings offer potential to accelerate the design and deployment of adaptive restraint systems. To implement this, firstly, metamodels using Gaussian process regression were developed to predict specific occupant kinematics and injury risks in frontal collisions between vehicles with varying crash configurations. Furthermore, the optimal restraint settings for each crash configuration was identified using a genetic algorithm, taking into account the injury risk predictions from the metamodels. The frontal collisions were categorized based on crash pulse intensities and then represented in a static lookup table for quick retrieval of restraint settings based on a crash configuration. The restraint settings obtained from the optimization were validated with real-world equivalent settings, exhibiting lower injury risks in low and medium-speed crashes for the concerned vehicle model. Overall, the research presented demonstrates the application of lookup tables as a tool for development and operation of adaptive restraint systems. Furthermore, the combination of look-up tables with machine learning techniques could be scaled to suit the complexity of the engineering problem
- PostUsing Design to Facilitate Self-Catheterisation for Tetraplegics with Low Hand Function, Proposing a Product Concept and Design Guidelines when Designing for People with Lower Tetraplegia(2024) Ankarbåge, Estela M.; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Aryana, Bijan; Eriksson, SiwThe master thesis project “Using Design to Facilitate Self-catheterisation for Tetraplegics with Low Hand Function. Proposing a Product Concept and Design Guidelines when Designing for People with Lower Tetraplegia”, by Estela Marie Ankarbåge, was carried out at the department of Industrial Design Engineering at Chalmers University of Technology. The project has been performed in collaboration with Wellspect HealthCare situated in Mölndal, Sweden. People with a high spinal cord injury, also called tetraplegics, are encouraged to manage activities of daily life independently to increase their self-esteem and self-confidence. Wellspect HealthCare noticed them struggling to empty their bladder by intermittent catheterisation. Although many are capable to perform the catheterisation independently, they may still need assistance to manage the various catheter products. The aim of this study was to investigate the user experience of intermittent self-catheterisation among tetraplegics with low hand function and explore if and how a product could be designed to facilitate the self-catheterisation procedure. We investigated what barriers prohibited the users from experiencing an easy intermittent catheterisation and how a product could be designed to facilitate intermittent catheterisation and increase tetraplegics’ independence. This was a qualitative study looking to discover and understand attitudes, experiences, and emotions connected to self-catheterisation. Six users, three healthcare professionals, and Wellspect employees partook in interviews, a focus group, and a workshop. The data was organised into general themes and looked at from a product pleasure perspective that provided a holistic understanding of the user experience. It was found that people with lower tetraplegia struggle with catheter products not catering to their low hand function, which makes their self-catheterisation experience filled with negative emotions. Emotions such as worry, shame, and disgust emerged before, during, and after catheterising. Users and experts alike found today’s procedure unoptimized for tetraplegics, where several product interactions required a higher hand function. Based on these insights, a conceptual product design was created to remove an important barrier to an easier self-catheterisation: attaching an extension tube to the catheter. The concept was later evaluated by a urologist who compared today’s user experience with their perspective of the user experience with the concept. Additionally, design guidelines were formulated to aid in future product development projects for tetraplegics with low hand function.