This study explores the effectiveness of a multisensory relaxation program developed for a high performance coupe interior by a German auto manufacturer. There is a growing need to introduce sensory-rich cabin experiences that bring about stress alleviation coupled with improvement of attention. The aim of this research is to evaluate whether auditory, visual, and tactile stimuli can facilitate relaxation in occupants following a high-arousal driving task.

A total of thirty-three participants were subjected to four therapy program conditions in a counterbalanced Latin Square order: no stimulus (control), auditory-only, auditory + visual, and auditory + visual + tactile (vibratory) stimuli. A custom test buck was built for the therapy activities, emulating the interiors of a sports coupe. The therapies were preceeded by a driving simulation stressor. Physiological data such as electrodermal activity, pulse rate, and skin temperature were collected through a wearable device, while subjective responses were collected via questionnaires. A psychomotor vigilance task (PVT) was also paired with the questionnaires to measure response times.

Physiological data analysis reveals no statistical differences between the four therapy conditions. PVT reaction times show minor improvements post-therapy, aligning with expectations. However, subjective data indicates clear preferences among participants. The complete therapy was most frequently rated as effective, though many complained about visual overstimulation. In contrast, the audio-only condition was perceived most balanced. Notably, participants suggested an audio-tactile configuration omitting the visual component.

These findings show that while objective data is still inconclusive, subjective feedback support such multisensory integrations in automotive interiors, particularly during idle EV charging phases or pre/post performance driving.

This report investigates the evolution of seating comfort during prolonged driving using a mixed-method evaluation of three production automotive seats. Twenty-six participants engaged in repeated 120-minute sessions within a full-scale vehicle cabin mock-up. Subjective measures, including comfort and discomfort ratings, local postural discomfort (LPD), thermal comfort, fatigue, stress, and tactile perception—were combined with objective indicators such as skeletal posture tracking, seat adjustment monitoring, anthropometric data and facial emotion analysis.
Temporal changes in perceived comfort were influenced by time, seat characteristics, user behavior, and individual anthropometry. Observable patterns emerged in both subjective responses and behavioral adaptations, revealing multifaceted interactions between thermal buildup, physical support, and postural fatigue. This paper suggests feasible design recommendations and offers insights to inform future design considerations for long-duration and autonomous driving environments.

This thesis investigates the development of Pathfinder, a wearable navigation system designed to help Visually Impaired Passengers (VIPs) navigate airports more independently. Large-scale transport hubs like Schiphol can be particularly challenging for VIPs due to their unfamiliar layouts, limited sensory cues, and reliance on visual information. Pathfinder explores whether smartphone-based Visual Simultaneous Localisation and Mapping (VSLaM), combined with intuitive feedback mechanisms, can offer a more autonomous alternative to traditional airport assistance.

The project followed a human-centred mixed-methods design approach, starting with contextual research and user analysis. Insights were gathered through desk research, interviews with experts and the user group, basic solution tests, and simulated context studies, where the researcher blindfolded himself and studied how blind navigation works. These methods helped identify key user needs, such as the importance of spatial orientation, environmental feedback, and a sense of control throughout the travel experience. Findings informed the development of a low-fidelity prototype and a refined system concept supported by flowcharts, user flows, and interface sketches.

The prototype was evaluated in a simulated airport setting at TU Delft to test how effectively it guided users along designated paths, responded to directional changes, and conveyed spatial and relevant information. Although testing did not directly involve blind users, the results indicated that the system enhanced route awareness and reduced reliance on human assistance. Participants responded positively to the audio-haptic feedback and the structured, intuitive nature of the guidance provided.

Limitations remain, particularly in real-time environmental adaptation and the prototype’s dependency on static maps for references. The lack of testing with actual VIPs also limits the depth of validation. Nevertheless, the project outlines a clear path forward, recommending steps such as API integration, improved feedback personalisation, and deeper co-design with blind users for future iterations.

Ultimately, Pathfinder demonstrates how VSLaM technology can be reimagined to meet the accessibility needs of visually impaired travellers. With further refinement and collaboration, systems like this could contribute to more inclusive, independent, and empowering travel experiences in airports and beyond.

This report details the development of a device that utilises image detection and machine learning to predict slug infestation in greenhouses. Increasing pesticide regulations have led to a rise in slug infestations, causing significant crop damage. Although alternatives to pesticides exist, they are expensive and labour-intensive to implement across large greenhouses. The goal of this project is to reduce labour by automating slug monitoring through image detection and machine learning. The focus is narrowed to detecting the Spanish Earthslug (Lehmannia Valentiana) in Cut Cymbidium, a type of orchid, as this market is particularly affected, and one slug species makes image detection more manageable. Context research and experiments were done to understand the problem. Slugs are nocturnal creatures that emerge from the soil periodically for food. Their activity is mainly influenced by temperature and humidity, preferring moist environments at around 17°C. Since greenhouse conditions vary by plant growth stages and change throughout the year, it is worthwhile to monitor activity on a longer time scale. Image detection and computer vision are already used in pest control and other applications within greenhouses. For efficient image detection, the looked after objects must be clearly identifiable and the images should preferably be of consistent quality. To achieve this in a greenhouse a good suggestion would be a controlled environment with minimal to no leaf occlusion. In our case, another important factor is having low data images with a high contrast between the slug and their background. This can be achieved by adjusting lighting conditions, converting images to black and white, and tracking changes between images to detect slug movement. After these results, the direction was chosen to predict slug infestation based on environmental data using counted slugs through image detection as a reference. Based on these insights, a device concept was developed using a Seeeduino Xiao ESP32S3 Sense microcontroller and Grove sensors. The system lures slugs with wheat bran, a proven bait, and uses a camera to capture images. Photos are stored on an SD card along with environmental measurements, such as temperature and humidity. Field tests and prototyping demonstrated that a 12 cm-high container with four 1 cm-diameter entryways was effective for attracting slugs and capturing quality images. To enhance contrast and prevent mould growth, a white mesh was placed between the bait and the slugs. For easy processing and low data images, the images are processed into binary images, where pixels are either black or white, and Hough Circle transform is used to crop the images around detected circles. For slug population prediction, a regression algorithm was selected, with environmental variables serving as the input and slug counts as the output labels. Spatial interpolation can be used to estimate environmental values for the entire greenhouse based on measurements of the device therefore getting the data to make predictions for slug infestation. The final version of the device, called Cephal, was tested in the field and used to build an image detection model. During field tests, Cephal successfully captured environmental data and collected over 485 images, although no slugs were detected, indicating the need for further research. Additionally, improvements such as a longer cable for the moisture sensor and a more accurate DHT sensor are required. With Cephal, a dataset of 482 images was used for machine learning. Reducing the input size to 64x64 binary images, a CNN model was made with around 90% accuracy. In conclusion, Cephal has the potential to enhance slug monitoring in greenhouses. With improvements in sensor performance and further optimisation of the machine learning model, Cephal could accurately predict slug infestation, helping greenhouse owners implement timely pest control strategies. Future work should focus on optimising the electronics and training and optimising the slug prediction model based on environmental values.

Prosthetic socket design and fit are key for a successful amputee rehabilitation and comfort, directly influencing patient satisfaction and quality of life. However, there is a lack of quantitative data on stump pressure distribution and how it changes over time, which could greatly contribute to the efforts of designers, prosthetists and doctors to improve patient comfort.

This study explores the use of Force Sensitive Resistors (FSRs) to measure and visualize stump pressure distribution, specifically for transtibial prosthetic sockets. The research involves testing an experimental prototype equipped with FSRs on a cyclic loading machine, followed by a comparison of the results with a simulation.

The findings indicate that the highest loads are registered by FSRs positioned at the bottom of the stump and below the knee. Some anomalies were observed, potentially due to specific geometric features of the prototype and the way the load was applied during testing.
Overall, the experimental data suggests that FSRs are effective for measuring stump pressure distribution. However, further testing with increasingly complex load cases is necessary to validate the sensors' reliability.

In conclusion, FSRs demonstrate significant potential for enabling knowledge-based designs focused on patient well-being. Through the course of this project, valuable design insights and requirements for integrating sensors into prosthetic sockets were identified. Moreover, this systematic sensor testing approach can be applied to explore and compare between other pressure sensors.

This study investigates passenger postures in future Level 5 autonomous vehicles (AVs) where the absence of driving responsibilities allows for greater freedom in seating. Building on existing literature on AV development and posture analysis, the research explores how passengers might position themselves when free from the constraints of traditional car seats.

To examine these natural postures, participants were invited to construct a "Build-Your-Own" seat using foam blocks, enabling them to achieve their most comfortable positions during various non-driving-related activities (NDRAs) while also sitting in an existing car seat as a comparison. Thirty-six participants, with diverse anthropometric characteristics, were involved in the study. The research setup ensured ethical considerations were addressed, and a range of measurement methods were used to capture joint angles and subjective comfort levels.
Results indicated that participants rated the Build-Your-Own seat significantly higher in comfort compared to conventional car seats, especially for the upper body and limbs. Analysis of joint angles revealed key differences in the shoulders, thighs, knees, and ankles, suggesting that future vehicle seats might need to be designed with these areas in mind for enhanced comfort. The study also noted that the Build-Your-Own seat allowed for more diverse and less predictable postures, particularly during activities such as Rest and Relax or Sleep, where freedom of movement was highly valued.

Further analysis of posture support highlighted the importance of armrests for certain activities and the necessity of calf support for others. The study also found that crossed-leg postures were preferred by a significant portion of participants, suggesting that future vehicle designs should accommodate such variations.

Comparative analysis between the one-g NBP (Neutral Body Posture) derived from this study and existing zero-g NBP data, as well as recommended joint angles for SUVs, revealed challenges in directly applying these models to future car seat designs. The influence of gravity on posture was significant, indicating that optimal joint angles in a zero-g environment might not directly translate to one-g conditions.

The study concludes that future AV seating designs should consider the diverse and dynamic postures passengers may adopt, emphasizing the need for more adaptable and supportive seating solutions. Future research should focus on asymmetrical postures and longer-duration studies to better understand the long-term effects of different seating configurations, especially in the context of crossed-leg postures.

Overall, this research provides valuable insights into passenger comfort in Level 5 AVs and suggests directions for future vehicle seat design that prioritize natural and comfortable postures in a gravity-influenced environment.

The automotive industry is looking at improving their new cars in different ways. Comfortability is a hot topic since it is dependent on so many aspects. The entire interior of the car influences how comfortable the end user is. Furthermore, autonomous vehicles are rising. That means that people have a lot of time to do other things while commuting, an activity that sticks out is relaxing and sleeping. The reclining of a car seat usually is arranged in one joint between the seat pan and the backrest. That means that the entire backrest is straight. However, the spine moves differently. This research shows that especially in a laying position the spine is quite rounded. To be able to support the body and optimize comfort, it would be ideal to have the seat follow this movement of the human body. After the research, ideation and conceptualization were performed. From this, a final concept direction was chosen and improved on the hand of anthropometric design. In the end, a simplified working prototype was constructed. The evaluation test was perceived as relatively good but also showed improvement points, as stated in the final recommendations. To conclude, the principle of creating a more rounded backrest works, and the prototype scored slightly lower on comfortability than the original seat. The concept has the potential to improve the comfortability of car seating.

Maatbril delivers personalized 3D-printed glasses by making a 3D scan of their client’s head and modelling the glasses around this 3D model. This is especially handy for people with cranio-facial differences or other conditions that prevent them from wearing regular glasses. A large proportion of Maatbril’s clients are children and/or have a mental disability. Interviews and observations during scanning procedures showed that the 3D scanning procedure is often perceived as scary. Moreover, it is often challenging to get the client to sit still for about 20 to 30 seconds, which is the time it takes to capture the 3D scan. The goal of this project is to design a non-invasive and versatile 3D scanning solution that produces high-accuracy 3D head scans near instantaneously, with simple controls for a single user. This 3D scanner will mainly be used by Maatbril employees, but it might occur as well 3D scanners will be located at healthcare institutions such Bartiméus and people that are no experts in 3D scanning will perform the 3D scan. Experiments and roleplaying with different interaction concepts showed that not all participants have the mental capability to actively contribute in the scanning procedure, ruling out principles like gamification to get the client to sit still. Eventually, it was chosen to attract the client's attention with an integrated tablet which displays videographical content. This requires little mental effort, but still allows for the client to have something interesting to focus on, so he/she will sit (relatively) still. In the meantime, the 3D scan can be captured. The final 3D Head Scanner makes use of 2 Azure Kinect DK sensors to capture the subject’s face along with the requisite landmarks in about 25 milliseconds, with only the click of a button. These sensors work with Amplitude Modulated Continuous Wave (AMCW) Time-of-Flight technology, which was selected after evaluating all options and fit to this use case. About 20 seconds after clicking the button, both scans have been aligned and the quality can be evaluated in the User Interface. The client probably didn't even notice any of this, as he/she was watching their favourite show on the digital tablet. Repeatedly testing and optimizing the interaction of the final 3D Head Scanner resulted in a relaxed and non-invasive 3D scanning procedure, where no force or bribing of the client was required to obtain the 3D scans. After optimizing the alignment algorithm, 3D scans with an accuracy of 1.2 mm can be expected, which is in the range of accuracy Maatbril requires when designing their glasses.

Integration of the sensory systems inside patient-specific medical devices (e.g., implants or prosthesis) can provide additional measurement data at different time points. This can result in improving the traditional designs of those medical devices, and consequently leading to increasing the patient’s comfort and quality of life. By doing measurements directly on or inside the patient, information can be gathered more specifically, which is important for improving detection and diagnosis. Next to that, it enables better decision-making for therapies, treatments and the allocation of prosthesis, causing improved rehabilitation. Problems with the comfort and fitting of the prosthesis can have a big impact on the life of the patient wearing the prosthetic. If there is lack of comfort, the patient is less likely to wear the device and that could limit the rehabilitation and satisfaction about their life in multiple areas. To get a better insight in the transtibial prosthesis in particular, and possibly solve the problems that occur, measurements can be done at the interface of the patient and the socket of this prosthesis. The data can be used to visualize the problem more accurately and, as a result, the response and treatment process can be chosen in a more precise manner. First, a case study about the lower limb prosthesis was conducted. Several questions will be reviewed, including defining elements of the satisfaction of patients about their prosthesis, what current existing problems with prosthesis are and the reasons of patients why they are not satisfied with their prosthesis. Then, two types of sensors will be used to visualise the problems occurring at the interface of the socket and the residual limb. One type of sensor is the piezoelectric pressure sensor. It is used to map the pressure on the limb inside the socket. Several experiments have been done with an existing 3D printed socket design and the data is compared to a finite element model that predicts stress distributions to validate this model. The model itself was changed on multiple areas to get closer to test conditions and improve model outputs. To be able to improve such models, the test-procedure should be further revised. After that, thermistors were used to measure the temperature within a 3D printed socket. A design for a new socket has been made to actively use the temperature data and cool the residual limb inside the socket when needed. This is done by integrating air-channels within the structure of the 3D printed socket and air is forced through those channels with a power-fan. The design has been validated with several tests and it is improved based on that. Those tests, calculations and estimations have shown that the current design may be able to cool the residual limb when further improved and optimized. In the end, several suggestions and recommendations for improvements were provided. Some of those improvements could be made in the size of the air-channels and the interface between socket and residual limb. Finally, present and potential (ongoing) developments on how to change the patient's condition, as well as how to apply promising developments in innovative ways, will be addressed.

The angle of attack (AOA) of an airplane changes the direction of the gravitational force on passengers and this thereby might influence passengers’ flying experience. However, the contribution of the AOA regarding comfort/discomfort is not fully explored. In this paper, we aim to fill this knowledge gap by identifying the relationships between the perceived comfort/discomfort of passengers and the AOA of the plane during the take-off and climbing phases of a flight. An experiment is conducted in a Boeing 737 fuselage where 26 participants were recruited. Each participant experiences 3 setups of seats with different AOAs (3, 14 and 18 degrees) for 20 minutes, respectively. Participants were asked to complete questionnaires during each session, and their heart rate and the pressure on the seat and the backrest were recorded as well. Experiment results indicated that participants experienced 14 degrees as the most comfortable angle with the lowest discomfort, which might be useful for airlines in setting up the take-off and climbing procedure. It would be good to check the findings in real flights.

By combining the recent innovations of 4D Printing and Printed Electronics, the Emerging Materials group at the Delft University of Technology has developed a new, printable, self-actuatable material that can continuously change shape in a programmable manner. A specifically designed strip of conductive and non-conductive materials exhibits flexion when exposed to an electric current, which can be used to control the actuation. The resulting actuator is small, lightweight, and can be printed as a single component. Several potential features of this phenomenon are explored, and its performance is quantified through a series of scientific experiments. The tools and knowledge obtained are presented in a series of comprehensive Design Guidelines and demonstrated by a locomoting robot. The project redefines the material’s properties under the new name “FlexTECH” and makes the technology more accessible to encourage designers in fields such as Aerospace and Soft Robotics to use FlexTECH actuators to solve future design challenges

 Starting this report 3Dprinting is explained and the state of the art in 3D printing structuralelectronics. From here the current state of the project is described afterwhich the project goal is formed. The project goal for this project is asfollows:  “Test and prototype on-sitecuring of solder paste on a 3D printed substrate to enable the 3D printing ofstructural electronics in prototypes using an FDM 3D printer”  After the project goal the vision for thefuture 3D printer is also discussed.  ResearchReflow soldering methods used in industry were researched and the mostpromising methods were chosen for the given use case of on-site curing ofsolder paste in a 3D printer. The most promising methods for on-site curing area thermode, a diode laser and focused hot-air. Also the used materials (e.g.solder paste and thermoplastic substrate) are discussed in more detail.  Testing of methods The three most promisingmethods were tried and tested to see which would be the most suitable method tocontinue with. Only the focused hot-air method produced usable results wherethe traces would be conductive.  Hot-airdetailed testing After determining that the focused hot-air method was mostsuitable method more detailed tests were done. Tests were conducted forprinting overlapping traces as a first step in printing in the verticaldirection. Trace pitch was tested for connecting DIP pitch components. As wellas how pins can be connected to the solder paste traces. And lastly tests aredone to quantify the conductivity of the printed and cured solder paste traces.Architecture of the system The system that was used for testing is described indetail. The system consists of a Ultimaker for printing the thermoplasticsubstrate and RepRap printing platform where the custom built solder pasteextruder and focused hot-air gun are mounted in. Design guidelines To use thedeveloped method for future research several design guidelines are described inthis section. First the CAD is discussed with the dimensions of the trace andhow components are to be placed in the design. After that the preparation ofthe Gcode for both printers is described. Demonstrator To demonstrate theabilities of the developed method a demonstrator product was designed and made.This demonstrator combines all the abilities that were tested separately in thehot-air detailed tasting chapter. Conclusions To finish this master thesis itis concluded that using this method of printing and curing as an alternative materialin 3D printing prototypes of structural electronics is promising. It is easy touse and affordable with sufficient quality to be used for prototypes. Howevertrue 3D functionality has not been achieved yet. Recommendations In this masterthesis a step forward has been made for using solder paste in 3D printingstructural electronics. To improve this method more research is needed andpossible steps for future research are discussed here. Creating consistentlayers would open up the possibility of stacking multiple layers and open upthe possibility of printing 3D structural electronics.

Because of cancer in the colon, parts of this organ might be surgically cut out to eliminate this disease. After removal, the residual parts are connected by means of a suture. A leakage of such connection is a severe complication and potentially life-threatening for the patient and associated with a poor healing of this surgical wound. Adequate blood perfusion plays a key role in this healing process and thus lowers the risk of such leakages. Understanding the tissue perfusion is therefore of the utmost importance. By means of a contrast dye, a special light and camera, this perfusion can be made visual, even underneath tissue. This imaging technique can provide the surgeon with essential information via screens that is not visible by the naked eye during an open surgical procedure. However, these images are still subjected by, amongst the perception of the individual surgeon, various external factors. Ideally, we could provide objective information that is not susceptible to these factors. To do so, software and hardware developments are needed. This project contributes to the development of the hardware. Factors that affect this objectification are allotted and it is researched how design can control or even eliminate them. The project focus on two of the major factorial influencers namely; external light and the manner of acquisition. The proposed design includes the means to exclude this external light and a manner to standardise distance from laparoscope to the surgical site. The design serves to assess if controlling these factors truly improves the objectification of the imaging technique in a pre-clinal setup.