Tactile interaction with surface texture significantly influences users' emotional and perceptual engagement with products. However, most wearable devices employ static material finishes or simple vibrational haptic feedback, which do not replicate the complex qualities of natural textures. This research aims to develop an interactive surface that incorporates dynamic textures to communicate emotion through touch.
Current research on morphing materials primarily addresses large-scale shape changes or low-resolution surface effects. These solutions are often bulky, rigid, or unsuitable for wearable applications. This gap highlights the need to design thin, flexible, high-resolution haptic skins capable of dynamically modulating textures to influence emotional perception through tactile interaction.
Following an evaluation of multiple morphing texture concepts, the research focused on the development of a hairy texture-changing interface.
The design combines a slitted top layer with a metal bristle bottom layer. When the top layer is fully up, the surface feels smooth and flat. When the Shape Memory Alloy (SMA) actuator pulls the top layer downward, the needles are exposed through the slits. This action transforms the surface into a coarse, sandpaper-like texture.
The resulting design is noiseless, lightweight, and flexible, which facilitates adaptation to various surfaces as a haptic interface for user interaction.

Background
One in three people requires rehabilitation, with the majority (90%) undergoing treatment at home. However, around 50% of patients do not fully adhere to their rehabilitation plans. IMU-based motion capture can assist both patients and rehabilitation specialists by addressing common challenges such as lack of motivation, time constraints, and incorrect execution of exercises. Integrating a visualisation tool into a smart garment using smart textile principles can offer an effective solution to these problems.

Project goal
The goal of this project was to create a proof of concept for an accessible smart shirt that integrates IMUs to capture and visualise upper-body movements for physical rehabilitation. The focus was on seamless integration, real-time motion visualisation, and aligning the design with patient needs.

Method
To ensure the concept aligned with the rehabilitation context and user needs, the project involved several key activities: desk research, expert interviews, benchmarking existing smart shirts, and prototyping. Insights were gathered from two rehabilitation doctors and two physiotherapists to understand rehabilitation practices and the needs of both patients and specialists. A benchmark of existing IMU-based smart garments helped identify ideas and challenges that needed addressing. A rehabilitation journey was developed to define the context, and a function diagram along with a list of requirements outlined the design criteria.

Prototype Development
The prototype development was divided into sections: motion capture visualisation, IMU integration, upper back design, wiring with conductive thread, and aesthetics. The motion capture visualisation focused on the electronics setup, rotational data gathering, and the use of OpenSense or Blender for visualisation. IMU integration addressed the placement and stability of the IMUs on the arms and their integration into the shirt. The upper back design explored the placement of electronics and the main node. Wiring with elastic thread focused on the conductive thread’s placement and sensor connections. These individual concepts were combined into the final design.

Results
Movi is the working prototype resulting from this project. It features five BNO055 IMUs, a TCA multiplexer, and a Xiao Seeeduino wired with conductive thread integrated in elastic for seamless integration. The system provides real-time movement visualisation through Blender. The shirt is designed with a snug fit, using a sturdy sports shirt as the base, and is costs 220 euro for the materials. It is designed for easy separation of electronics and textiles at the end of life.

To evaluate Movi a performance and user test were executed. The visualisation is clear, stable, and offers a 0.23-second delay. While the precision can be improved with calibration, a method has been proposed that patients can perform themselves. Feedback from users indicated that the shirt is comfortable and easy to wear, with a good fit for women (sizes S and M) and a slightly tighter fit for men.

Conclusion
Movi demonstrates the feasibility of using IMU-based motion capture garments for real-time visualisation within the rehabilitation sector. It offers a more affordable and integrated solution compared to existing systems. The smart shirt allows patients to use it independently during exercises, improving their rehabilitation process at home. The patient gets visual feedback in real-time. Movi can be further developed into various applications, such as motivation tools, gaming, exercise guidance, progress tracking, and discussion tools for rehabilitation specialists, ultimately enhancing both the patient experience and the specialist’s ability to track progress remotely.

This thesis investigates textile-forms—textile-based artefacts designed through the integrated consideration of textile (matter) and form (artefact). Building on the concept of Multimorphism, which views textiles as a material system spanning material, social, and ecological scales, this research addresses the challenges of designing interactions deeply rooted in the textile material system.
Grounded in the Materials Experience framework, the thesis examines textile-forms' performativity—their capacity to invite action—and their multi-situatedness, or adaptability to diverse contexts. Using a mixed-methods Research-through-Design (RtD) approach, the research investigates textile-forms' performativity across three levels: design practice, interaction, and user experience. Two series of woven textile-forms, created through weaving and multi-layer weaving techniques, explore how specific textile qualities contribute to performativity and how textile-forms can be designed for everyday use. Empirical studies reveal that textile-forms with unpredictable behaviours and multiple embedded states encourage creative actions and reflective experiences. However, the studies also highlight challenges, such as user confusion caused by open-ended functionality and evolving material states.
This thesis demonstrates how designers can use textile-form thinking to leverage textiles' performativity, enabling rich interaction possibilities inherent to their textileness. It also emphasizes the gap between textile-forms' potential for richer interactions and user acceptance. In conclusion, the work advocates for multimorphic thinking, promoting holistic and ecological approaches to designing interactions with textiles that embrace their unique temporal, unpredictable, and multi-situated qualities.

Pneumatic actuation is an effective method for recreating human touch sensations because it can apply pressure to the skin and has a natural softness. However, integrating this technology into fully wearable devices has proven to be difficult due to the lack of responsiveness with smaller pneumatic components, which limits the number of effective touches that can be portrayed.

Mobile Touch is a fully wearable system designed to deliver touch sensations to the wrist through a combination of pneumatic and vibrotactile actuation. By compensating for the inflation time of the pneumatic component with vibrations, the system's responsiveness is increased, allowing for the creation of more varied touch patterns. In addition, a wireless controller was developed that allows for programming touch patterns and directly transmitting touch wirelessly to the wearable device.

In the user study, the pneumatic-vibrotactile modality generally received significantly higher ratings for its similarity to human touch and pattern recognition by leveraging the strengths of each individual modality (n=35). Specifically, for longer touches, it was more effective due to its ability to mimic the softness of human skin and the pressure of a touch. For short taps, the vibrotactile component was clearer and enhanced the perceived realism.

This project focuses on developing a functional wearable prototype that can monitor changes in breathing behaviour by integrating textile sensors. The project was initiated by Mediventic, a healthcare industry start-up aiming to simplify the diagnoses and treatment of Chronic Hyperventilation Syndrome (CHVS) by creating affordable home-use smart clothing embedded with sensors that objectively record a patient’s biomedical data. Medical literature highlights the challenges of accurately diagnosing medical conditions in the healthcare industry, particularly CHVS, which is prone to errors due to the unusual range of complaints and symptoms. Medical professionals underline the need for wearable instruments to detect tell-tale signs and provide preventative treatment. On the other hand, current applications of smart textile wearables often lack focus on a specific problem.

To better comprehend the problem and solution space, fundamental medical themes and the current status of wearable technology are reviewed. Important annotations about CHVS are concluded, emphasizing the close link between psychological and physiological elements that drive the self-perpetuating cycle of chronic hyperventilation and the development of symptoms. To assist the patient in gaining respiratory control, the use of wearable technology to support treatment processes is investigated. In particular, ‘smart textiles’ resemble an attractive medium for the integration of sensors and electronics. Respiratory movements can be captured at various points on the upper body utilizing strain sensors embedded in the textile medium. This allows a wearable to preserve valuable qualities for
user experience typical for textiles such as comfort, flexibility, and aesthetics.

During prototype development, performance, manufacturability, and usability requirements are translated into tangible prototypes, such as the fabrication of working knitted strain sensors for tracking breathing behaviour. Different versions are fabricated through iterative steps and intermittently tested for performance and usability. Throughout development, the steps for fabricating and integrating components as a ‘textile system’ are made insightful. Through user testing, the final prototype is used to evaluate sensor performance and as well assess for comfort and usability. Participants are instructed to wear the prototype in several active positions and perform breathing tests.

Conclusively, the results and development process are contemplated concerning the project’s design requirements and initial aim. Although the data’s usefulness must be evaluated by medical professionals, the results suggest that utilizing knitted sensors for measuring breathing behaviour is successful enough for real-time data collecting, even with basic prototyping components. Information regarding breathing rate and depth of respiration can be interpreted at different locations on the body. Also, the prototype design appeals to the imagination during user tests. Users associate the prototype with regular clothing and results indicate that the wearable-textile form factor allows for unintrusive monitoring of breathing behaviour. However, developments must be made to improve the reliability of the construction and durability of the sensors. Depending on the definition of signal detail, signal amplification and noise suppression might elevate the quality of information to the next
level.

The process of physical rehabilitation in most cases consists of visits to a physical therapist and exercises the patient is expected to perform at home. To increase or maintain strength or flexibility these exercises need to be performed regularly. Practice teaches us that not all patients succeed here. In this project, we look into what is keeping them from succeeding and how we can support this process.

In literature, four categories of barriers are described, from which the psychological barriers are most interesting to investigate further within this project. Motivation plays a big part within this category.

The Fogg model gives structure to the different components of motivation and different factors influencing the execution of preferred behavior. It shows us triggers will fail if motivation is low or the task takes too much effort to complete.

In a lot of the cases, the intention to complete the exercises is present with the client, but the behavior does not reflect this intention. The intention-behavior gap can be bridged the same way the fogg model suggests triggers to be efficient, by motivating the user or making the task take less effort.

By providing support during the exercise - providing both motivation and decreasing effort - and giving the patient the opportunity to track their progress after doing the exercises for a longer amount of time we can increase the exercise adherence.

To provide support, we need to gather data on the movements that are made during the exercise. We developed a textile stitched strain sensor that tracks the angle of a joint. The sensor has conductive thread stitched in a tight zigzag pattern onto Kinesio tape. Since the tape is adhered to the skin, the sensor experiences minimal hysteresis.

Using the data gathered by the stitched strain sensor, we tested giving back different kinds of feedback using two different actuators. We found that giving the test subjects more precise data on their movement made them more accurate, but at the same time, made them experience their movement as less accurate. This on the one hand, gave them more motivation to improve, but also made them less confident in performing the exercise.

The project proves that using the real time data gathered by the stitched strain sensor can add to better executing of on exercise and has potential to with that data also contribute to long term exercise-adherence.

The focus of this project was the research and development of an affective social touch wearable. AffectiveAir uses pneumatic actuation on the shoulder to convey a library of haptic sensations. The goal was to overcome physical limitations in potential digital communication contexts, by a non-verbal, tactile, and possibly intimate social touch using pneumatic actuation. This would offer a way for individuals to connect, much like in face-to-face interactions

The embodiment of the prototype is the result of an iterative design process based on literature research, benchmarks, and user tests. The wearable actuator, designed to be worn on the back of the shoulder, is secured using an elastic band that attaches to the wearer’s pants. A custom-designed, thin polyurethane airbag with an integrated nozzle provides a soft, textile-integrated actuator solution. An external pneumatic control system controls the airflow, allowing for inflation under 1000- and deflation under 100 milliseconds. Effects of the actuator are monitored using an air pressure sensor and force sensitive resistor, offering controlled feedback and data logs for prototyping and user research.

Multiple user tests functioned as a means to explore and verify new designs throughout the project. Initial tests identified the shoulder as an effective and acceptable location for the feedback, and an airbag of 40x40mm was determined to provide the best balance between intensity and comfort for this specific location. Subsequent tests determined optimal pressure levels for pneumatic haptics on the shoulder and evaluated user responses to various pneumatic patterns.

Results revealed that it was challenging for participants to distinguish pressure levels from each other within the 0 to 500 mbar range. However, there were promising results in the general identification of increasing or decreasing pneumatic patterns using three pressure levels of 75, 200 and 500 mbar. ‘TripleShort’ received the highest identification rating at 85%, while ‘short staircase down’ received the lowest rating at 44%.

Patterns with a prolonged high pressure level at the end such as ‘heartbeat forward’ and ‘long staircase up’ received a slighly higher comfort and pleasantness rating compared to others, where the latter was rated the least exciting at lower speed. Overall ratings remained close to the median across tests with variable speed or pressure levels.

General user feedback on the prototype and haptic experience was positive, with participants noting the novelty and the sensation’s occasional resemblance to intimate human touch. Feedback from the interview also notes how context and social relationship status closely relates to the acceptability of receiving such feedback. The ergonomics of the prototype were considered satisfactory, allowing for adjustment to fit any body size and position the feedback on the back of the participant’s shoulder.

In conclusion, AffectiveAir demonstrated the potential for affective touch through a pneumatic shoulder wearable. It offers a library of identifiable and characterized pneumatic patterns and the ability to extend the possible actuations with adjustable parameters. The project’s outcomes suggest promising potential for further research using affective pneumatic haptics, applicable not only in mediated communication but also in other possible areas such as gaming and navigation.

Cardiovascular disease is one of the leading causes of death, representing 32% of all global deaths. The mainstay treatments are medical compression stockings (MCS) and physical activity. Although MCS has been shown to positively affect treatment and support disorder control (e.g. leg swelling), research shows incredibly low therapy compliance.

Throughout history, the involvement of digital technologies has greatly enhanced healthcare.
Nonetheless, developments are not embraced by the medical compression stockings industry yet. For instance, since the invention of medical compression stockings (with a graduated compression) in 1960, the design of medical compression stockings (MCS) has hardly changed.

This thesis explores the integration of sensors into medical compression stockings and aims to innovate current compression stockings by including wearable technology. The feasibility and viability of smart stockings are examined, and barriers are defined through a combination of interviews, literature and user observations. Findings are translated into design requirements.

Throughout the research, multiple problems have been identified, ranging from user dissatisfaction to product shortcomings.

For instance, MCS only have an expected lifespan of half a year. Yet, MCS are yearly reimbursed by health insurance companies. Also, wearing, product care, and health complications can even shorten the lifespan of MCS.
For the successful treatment of disorders, it is essential that MCS exert the correct amount of compression.

The presented smart stockings with the app address these shortcomings. The smart stocking is able to monitor the exerted compression of MCS. By constantly validating the product, users gain ownership over the quality of their compression therapy.

Aside from product validation, compression monitoring is translated into the level of fitness of the user. Increased compression (outside of the walking range) indicates an expanding circumference of the ankle. Together with a vascular surgeon, guidelines are discussed. The combination of the smart stocking and the app has the potential to give medical recommendations to users.

With the app, users can be rewarded for their therapy adherence and goals tailored to the specific user and their physical capabilities. Lastly, not every healthcare complication is immediately measurable through compression change. Therefore, the app can ask additional questions based on visible signs, this way it also coaches users to monitor their health.

There is a raising demand for player statistics in the world of football. With the developments over the last years in wearable sensors, Human Activity Recognition (HAR) based on wearable IMU sensors can be used to tackle this problem. This thesis builds upon an earlier research done for this topic, where an end-to-end pipeline based on deep learning was created that is able to be trained and used for football activity recognition. The goal is to test and improve said pipeline. This was done by adding change of directions (COD’s) to the classifiable activities. Furthermore, run velocities were build as a spectrum with several categories depending on the speed. A combination of convolutional and recurrent layers resulted in test accuracies up to 88.9%.
Afterwards, the pipeline was used to evaluate larger datasets containing football drill and a football physiotherapy training. For this a sliding window evaluation procedure was proposed. These evaluations gave promising results. Many actions and football related activities could be recognized, however many smaller, shorter actions were missed. This can be seen as lack in trainingdata. In this data, little activities with the ball were present. Hence the deep learning models could not be trained accordingly. Later, it was researched
if additional training of activities with ball increased the evaluation. This was indeed confirmed, since the evaluations showed more detailed and realistic results. Including even more additional trainingdata, could result in the pipeline performing reliably in real-life football scenario’s.

This Master’s thesis report contains research about applying textile to the outer housing surface of products. The research was conducted in collaboration with Signify, a company that creates smart home luminaires for the brand Philips Hue. The goal of the project was to create design guidelines which the designers of Signify can use to create textile building blocks for their luminaires.

The project explores suitable textiles, shaping possibilities and fastening methods. The most relevant insights are summarized on “Design Guidelines” pages. A “Design Decision Tree” (DDT) was created to navigate through the Design Guidelines. The DDT can be used by designers who have a housing shape in mind to learn about the relevant insights for applying textile to their specific surface.

Suitable textiles for surface application are researched. It was determined that knitted and woven fabrics are suitable for surface coverage. Non-woven fabrics are not because of their undesired appearance and minimal required thickness which impedes mechanical fastening.

Shaping possibilities were explored for covering surfaces with flat sheets of fabric as well as covering continuous surfaces with tubular textiles. Depending on the properties of a surface, certain fabrics and fastening methods can or cannot be used. The design limitations per surface category are summarized in the Design Guidelines.

Most current textile housings are fabricated by gluing or welding the textiles to the outer surface and inner edges of the part. This method obstructs easy disassembly. An alternative method was created. This “clamping” fastening method is considered more sustainable because it allows the housing to be disassembled with ease and therefor repaired or recycled more efficiently. A clear use cue was added to the inside of the clamping mechanism to inform the user about its disassembly potential.

In addition to the gluing and clamping method, creating a separate sleeve was explored. To fabricate such a sleeve, 3D-knitting can be used. Literature research was conducted to explore the possibilities of knitting three-dimensional shapes on flatbed and circular knitting machines to cover product housings.

A novel product concept for Philips Hue was created. A prototype of the concept was made to demonstrate textile building blocks in the context of a luminaire. This product concept is called the “Rotation Lamp” and it is used as a tool throughout the report for experimenting and validating. The Rotation Lamp is inviting to touch because of its textile parts. It is intended to be kept close to the user and to enhance their well-being by providing them with a lamp that suits their need for ambience and functional light. Three sets of textile housings were created for the prototype to observe the different product aesthetics that these could create.

This graduation project set out to design a modular interconnection system for smart textile applications for Elitac Wearables, that is widely implementable, robust, durable, cleanable,cost-effective, more integrated in the textile carrier and ergonomically to wear. The Double Diamond Design Process methodology of the Design Council (2015) is adjusted to a 4 phase Diamond Design process to guide the process towards a final embodiment design.  Phase 1. Understanding the problem: In this phase the focus lies on finding the key challenges Elitac Wearables is facing when designing smart textile wearables. The challenges identified are: the lack of proper integration of electronics & the textile carrier, and no robust and durable (inter-)connections. Furthermore, cable management poses a real challenge as classic electrical wiring is used. A fourth challenge is the cleanability and waterproofing of designs, allowing them to be laundered by users. Also, products are not fit for mass production due to the lack of scalable production processes, the availability of parts for longer periods of time and high prices. All findings were summarised in a problem definition and a program of requirements & wishes. Phase 2. Finding building blocks for haptic feedback systems: Technology literature research and practical tests are conducted to select technologies that can help solve the problems found in design phase one. The technologies are rated on mechanical properties,conductive properties, processability, stretchability, flexibility, durability,and costs. High potential technologies I selected during this research range from wire connections, electrical connections, integration techniques from electronics & textiles and removeable Furthermore, in this study, the solution has been divided into four modules: The tactor (containing an ERM and a driver PCB), the power & data transport (interconnecting all electrical modules), the main controller (containing the micro controller and power supply) & the textile carrier (which makes the technology wearable). Phase 3. Mounting haptic feedback systems to garments: Multiple concepts are generated of which two are selected: The first concept is based on conductive yarn knitted pockets & conductive Velcro as connector while the second concept implements sewn conductive yarn traces and a pogo pin connector. First tests show good data reliability and launderability properties. In the end a hybrid version of the two concepts is chosen. Phase 4. Embodiment design of the haptic feedback system: The final embodiment design implements a power and data transport system consisting of 4 non-isolated sewn conductive yarn traces to enable I2C communication. The waterproof and overmolded tactor module integrates 4 conductive strips, that are pressed against the conductive yarn traces inside pockets as electrical connection. The main control module is connected through a magnetic male pogo pin connector. An overmolded landing spot with the female pogo pin connector acts as easy attachment point for the main module. A functional prototype powers 3 tactor modules at the same time and user tests show a high level of comfort, but also room for improvement of the interaction when placing the tactor modules inside the pockets and the size of the main module. When reconsidering the goal of this graduation project (the design a modular interconnection system for smart textile applications for Elitac Wearables, that is widely implementable, robust,durable cleanable, cost-effective, more integrated in the textile carrier and ergonomical to wear), the design fulfils most of the requirements. The final design scores well on the following design drivers: widely implementable, scalable, cost effective and cleanable. However, the robustness and durability of the design is still questionable when it comes to corrosion of conductive yarns caused by artificial sweat. The wire fragmenting is also something that will need to be prevented in future designs. Moreover, the ergonomics of a prototype of the design is rated to be comfortable during user tests as it does not restrict participants in their movement and the electrical modules are barely noticeable. Though some aspects of the interaction require improvement.

This graduation report describes the design of an ice cooled liquid circulation cooling vest for INUTEQ, a company specialized in personal cooling. The new design, the INUTEQ ICE, is made for warehouse and factory workers. They need cooling vests, because they work in large buildings with flat roofs. Large buildings cannot be cooled by air-conditioning anymore and the sun can heat them up to tropical temperatures. Additionally, the temperature may, in some cases, be increased by the production processes inside. Working in the heat can decrease productivity, performance, comfort and safety. The physical work these people perform also increases their chances of heat related illnesses such as: heat rash, heat cramps or heat exhaustion. In some cases, overheating can even lead to a heat stroke.
One of the solutions to cool people down is with cooling garments. The INUTEQ ICE is an improvement on traditional liquid circulation garments, which cool by running the water through silicone tubes. The new design makes use of open cell foam pads to increase the heat exchange between the cold water and the body. The developed cooling pad technology was found to have a nearly three times as high cooling capacity per unit area compared to liquid circulating cooling technology currently on the market. In the same experiment, the cooling capacity per unit area of the new pad technology was found to be similar to existing 6.5°C PCM packs and higher than 15°C and 21°C. The design has the potential to cool for longer than the 6.5°C PCM packs. Contrary to evaporation and air based cooling vest, the INUTEQ ICE is able to be used underneath enclosed clothing and in other high humid environments.
The project contained three phases, an analysis phase, a development phase and an evaluation phase. In the analysis phase, relevant information about cooling garments and the target group is gathered. This information is brought together in a list of requirements. In the development phase, the cooling pad technology is developed and the cooling method is defined. The development phase ends with the first concept of the INUTEQ ICE. In the evaluation phase, a working prototype was made and user tested in the appropriate context, which provided useful insights towards the final concept. The evaluation phase also contains the previously mentioned cooling capacity test and recommendations to continue the project.
The end result of the project is a promising final concept, with working prototype. The INUTEQ ICE has the potential to become a product that, in humid environments, performs better than alternative cooling garments. With further development it can be used by different target groups, not only factory and warehouse workers. It seems likely that a finished version of the INUTEQ ICE can add value to INUTEQ’s product range.

Hyperthermia (HT) is a cancer treatment that is generally used in combination with chemotherapy or radiotherapy. During this therapy, electromagnetic energy is used to elevate the temperature of a tumour to 40–44 °C for 60–90 minutes. This process makes the tumourous cells more sensitive to radiation and chemotherapy.

Deep hyperthermia treatment of head and neck cancers is usually administered for recurring tumours in this area that are positioned more than 4 cm under the skin. Patients with recurrent head and neck cancer have a 2-year survival rate of only 10-20 % when retreated with chemotherapy and radiotherapy. Furthermore, toxic side-effects of these therapies are even more severe after re-treatment. Hyperthermia treatment can be a good solution for these problems, but currently, there is a lack of deep heating equipment for neck and head. That is why Erasmus MC is developing applicators for deep, targeted heating of these areas.

After two iterations, Erasmus MC has recently developed a novel MR compatible head and neck hyperthermia applicator (MRcollar). A water bolus needs to be placed between the applicator and the patient’s skin to act as a cooling agent to prevent skin burns and as a transferring agent to conduct the electromagnetic energy to the internal tumour tissue. However, there is no water bolus developed yet to be used in this applicator. Therefore, this thesis focused on developing a bolus for the MRcollar.

By analysing the treatment context, the previous applicators and boli and talking to stakeholders, the main challenges for this project could be defined. The bolus should be comfortable for the patients: the pressure on the skin should be minimized and enough space for breathing and seeing should be provided to reduce claustrophobic feelings. The cooling must be effective and uniform throughout the bolus volume. Furthermore, the shape of the bolus should be stable, predictable and reproducible to efficiently simulate the treatment. The bolus should function in the MRcollar, not disrupting electromagnetic waves or MR imaging and being watertight. Lastly, the bolus should be easy to install by the clinicians.

Different ideas and concepts were generated based on these challenges, after which it was decided to make the bolus out of a flexible 3D printed inner structure, surrounded by a plastic film. This concept was further detailed, tested and improved during the embodiment phase with a main focus on creating an anthropometric fit, good water flow, flexibility and stability and creating a watertight enclosure.

The final design is a flexible, 3D printed structure with an implemented water guidance system. The shape is designed to ergonomically follow the shape of the head. The bolus is made watertight by gluing and sealing a plastic film around the structure. This design was validated and found to be successful on all earlier defined challenges.

been given to Human Activity Recognition (HAR) based on signals obtained by IMUs placed on different body parts. This thesis studies the usage of Deep Learning-based models to recognize different football activities in an accurate, robust, and fast manner. Several deep architectures were trained with data captured with IMU sensors placed on football players' bodies and their performances were compared. A combination of convolutional layers followed by recurrent (bidirectional) LSTM layers showed to achieve the best results with up to 96.71% of accuracy. When using normalized data via a calibration recording, these accuracies increased up to 98.2%. Results showed that deep learning models performed better in evaluation time and prediction accuracy than traditional machine learning algorithms. An end-to-end pipeline for football activity recognition was developed that can be extended to any other HAR task. With it, not only the training was explored, but also a sliding window evaluation procedure was proposed that can be used to efficiently analyze unseen IMU recordings and recognize the activities there present. This pipeline showed to be fast and robust especially with signals consistently calibrated and can be used to recognize movements on a real-time basis. It can be concluded that a combination of deep learning models and a sliding window evaluation procedure is suitable for fast and accurate HAR tasks and can be used as input for research on injury prevention. By training and evaluating the models with more data, ideally from uncontrolled experiments such as football matches, we expect to further improve the generalization property of the classifiers.

Electrochromic materials exhibit a reversible color change that is triggered by an applied voltage. Controlled color change, low voltage operation and the memory effect are three unique material properties defining electrochromic materials. As a result of an electron transfer or redox reaction, the material is able to switch between its bleached (transparent) and colored state. As this color change is a chemical reaction, it only requires an applied voltage to trigger and complete the electron transfer, thus afterwards the applied potential can be removed and the material will stay in its current state; i.e. the memory effect. Electrochromic materials are processed into a sandwich structure of thin layers that enable it to change color when a voltage is applied to it; i.e. an electrochromic device (ECD). An ECD operates through two electrodes that are connected to both the positive and negative of the voltage-source, and the two electrochromic layers. These electrochromic layers are separated by an electrolyte, that allows ion transfer, enabling change of color. Optimizing this layer structure, results into the definition of four stacking sequences, based on their vertical or co-planar stacking sequence (i.e. vertical stacking of the EC layers or merging of both EC layers in the same layer with separated electrodes) combined with the substrate used; conductive and insulating. These four stacking sequences are characterized on their transparency, shape/pattern changing abilities, coloring, design of the images displayed and interaction between the two EC layers; i.e. technical characterization. As result of this material characterization, ‘the puzzle of electrochromism’ is designed. ‘The puzzle of electrochromism is an edge-matching puzzle, with as goal to puzzle four geometric shapes by matching the sides of the adjacent puzzle pieces. Solving this puzzle communicates the goal of the demonstrator (i.e. the technical and experiential characterizations) to the puzzler, while emphasizing the simplicity and possibilities of integrating electrochromic materials in design. The ultimate goal is to inspire the puzzle to make use of electrochromic materials in their product designs, through exiting creativity and curiosity. When a puzzle piece is connected to the framework, a closed loop circuit is created between the voltage source and the coin cell battery, thus the puzzle piece will change its color. When the polarity is reversed (i.e. the puzzle piece is turned 180 degrees within the horizontal plane), it immediately switches from its primary EC layer to its secondary EC layer or vice versa. All primary EC layers will form the first puzzle to be created and all secondary EC layers the secondary puzzle. Meaning, ‘the puzzle of electrochromism’ is not just one puzzle, but includes two different puzzles. Besides the controlled color change, the other unique material properties it demonstrates are: low voltage operation, memory effect, simplicity and transparency. All individual puzzle pieces represent a different stacking sequence, through which the shape/pattern change (i.e. single and double image display), coloring (i.e. immediate and color flow), design of the images displayed (i.e. isolated and linked) and interaction between the two EC layers (i.e. overlap, connection and separation) are demonstrated. In the end, ‘the puzzle of electrochromism’ is a demonstrator making electrochromism easy understood, explainable and approachable for designers to use within their product designs; i.e. the aim of this thesis. On top of this, it is not only a good demonstrator but also a good puzzle according to the ten puzzle principles of Shell (2008).

The interest in shape-shifting materials has increased over the past years. A part of this field concerns the shape-shifting of sheets from flat configuration into a double curved configuration, requiring nonuniform strain among the sheet. This functionality can be used for various purposes, in different application fields. For example, shape-changing properties are increasingly used in tangible user interfaces. For activating these sheets, shape memory alloys (SMAs) lend themselves well. That is why multiple shape-shifting sheets that are activated with SMAs already exist. However, a new design is developed and explored in this thesis, in which SMA springs are used as compressive bendable actuators. This is different from the designs that are found in literature, and the distributed low bending stiffness could potentially lead to smoother shapes. The goal of the project is to create a SMA spring network that can deform out-of-plane into a specific shape and to explore possible applications. The idea is to prescribe this shape by prescribing the related nonuniform strain via controlling the springs individually. Through an iterative prototyping process such a network is developed. Flexures are included to impose the out-of-plane bending direction. Antagonist hoses are included to prevent these flexures from interacting with the springs and to draw the network back in plane upon cooling. In the final prototype, the shape of the network can be adjusted via binary activating the springs with Joule heating. More possible future applications of the network are explored through brainstorm sessions. In addition, a finite element model (FEM) is set-up to calculate the resulting shape upon an activation scheme. The important network parameters are tested and integrated in simple elements. The demonstrator can successfully deform out of plane into different shapes upon different activation schemes, although the shape control is low, and the overall shape not very smooth due to excessive local bending of the network struts. This could be diminished by increasing the bending stiffness of the struts. However, this would lead to less overall deflection as well. The control over the strains or the bending should be improved for enhanced shape control. To evaluate the FEM, the prototype is 3Dscanned and compared with the result of the FEM. There is a significant difference in the amount of deformation, which may be due to inaccuracies in the model or in the prototype. The validity of these should be improved before further evaluating the effectiveness of the simplified model.

We live in a society in which we rely heavily on energy. We need it everywhere and made great advancements which allow us to bring energy with us wherever we go; one of these advancements are batteries. In order to be less dependent and generate our energy locally when needed this project focusses on this topic. Creating a design framework which covers the development to smart clothing and a specific target group creates an interesting an specific final solution which still leaves an opening to alter the final product to be useful for multiple other industries

This project focussed on the use of smart textiles for full body posture monitoring and exploring the potential of a tight fitting catsuit to measure posture close to the body. A full body monitoring system (FBMS) that is wearable and easy to use, was found to be most relevant in the domain of first line care physical therapy(PT). As the form of the product was set in the beginning of the project, the ViP analysis was used to gain insight in the Domain of physical therapy, the context the FBMS is used, the qualities of the interactions users have with the FBMS and the features of the product. A fully textile based wearable system for monitoring postures is complex but not impossible. In terms of research in the field of wearable textiles, recent developments has shown a surge in possibilities and posture sensing abilities. The identified target users are female physical therapy patients with a young family who experience lower back pain. Prevalence of lower back issues are highest among musculoskeletal conditions and issues related to lower back pain have a large influence on the rest of the body. Here the posture changes due to poor posture behaviour, creating deformities in the body. These deformities can be measured by adapting strain resistive sensors to textile based sensors and integrated them in a tight fitting bodysuit. For this purpose, the zigzag stitch, shieldex 2-ply silvercoated yarn and 85% lycra proved most successful in obtaining a useful sensor signal. Here, posture and change in posture could be measured and provide the user with direct haptic feedback on their posture with vibration motors.

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