Access to prosthetics is very limited to many potential users, while the need is high. There are two main reasons for this that both are related to the production of prosthetics: the lack of skilled people and high costs. Minimized assembly production using 3D printing could be a solution: no training is required, assembly takes only a short amount of time and cheap materials can be used. Besides, 3D printing is a good method for customization. Therefore, this study proposes a 3D-printed finger for a bodypowered hand prosthesis with minimized assembly. The design approach is the following. First, the human finger anatomy is studied. Then, a stylized version of the human finger is made that includes only the functions required for the prosthesis. Finally, the design principles of the stylized finger are evaluated and structurized. Based on the design principles, a finger for a prosthetic hand is designed and a prototype is developed. The prototype is produced with an Ultimaker 3 using a rigid and a flexible material in one print. The evaluation of the prototype shows promising results. The finger is suitable for a hand prosthesis that can perform an adaptive power grip and a pinch grip. The mass of the finger is 17 grams, which makes the finger comfortable to wear. An actuation force of only 16 N is required to fully bend the finger. Minimized assembly and cheap production are achieved: only four assembly steps are required and the material costs are only 1.68 euros per finger. In conclusion, the prototype shows a promising step in the direction of a hand prosthesis that is affordable, functional, body-powered, and has minimized assembly

Background: While new prosthetic hands are developed to increase functionality and allow more complex movements, prosthetic wrists are researched less. Although there are wrists available, primarily featuring 1 degree of freedom (DoF), only a few prototype 3 DoF wrists are currently known. These 3 DoF wrists usually have sufficient range of motion (RoM), but they fail in delivering high torques while being lightweight and compact, which can increase chances of rejecting the prosthesis. Objectives: The purpose of this study is to design and evaluate a conceptual 3 DoF wrist that is capable of replicating the RoM of the human wrist while keeping the size and mass as low as possible. Furthermore, the wrist needs to be able to deliver more torque than existing 3 DoF wrists. Results: A functional 3 DoF prototype was created. The design is actively controllable using three motors and pumps but can also adapt to different surroundings if the motors are off. The prototype is capable of a total range of motion of 142° for exion/extension and 90° for ulnar/radial deviation and can provide estimated torques of 4.52 Nm and 7.29 Nm respectively. Pro-/supination was not measured, but can provide a theoretical RoM of 134° and torque of 8.9 Nm. The complete wrist has a length of 150 mm and a diameter of 50 mm at the thickest part, and a mass of 166 g (including fluid). Conclusion: A 3 DoF wrist that is theoretically able to provide more torques than previously researched wrists is successfully designed and tested. The available RoM approaches the required RoM, except for pro-/supination. Future research should primarily focus on measuring the front part of the wrist using higher pressure. The 3D printed pro-/supination part of the wrist should be further researched to improve RoM and remove leakage while pressurized.

A large proportion of upper extremity prostheses are abandoned by their users. Commonly, the main reasons for abandonment are related to comfort, control and cosmetics. Prostheses are often experienced as too heavy and have limited functionality. A pneumatic power source is able to provide a relatively high force using a small and lightweight actuator. However, state-of-the-art pneumatically powered upper extremity prosthesis offer either high grasp forces or the ability to adapt to the size and shape of an object. This article presents the design of a pneumatically powered hand prosthesis for toddlers, which focuses on being lightweight and highly functional. An underactuated 3-DOF linkage-based finger transmission mechanism was created and served as a proof-of-principle. The resulting prototype was 3D printed and tested following an elaborate list of criteria. The results demonstrate that the mechanism is capable of transmitting an actuator force of 100.5 N to a fingertip force of 32.3 N using 5 bar of pressure. The proposed mechanism also offers the functionality of adaptive grasping. The conceptual design and prototype show promising capabilities for the development of a lightweight and highly functional prosthesis for toddlers.

Lower limb exoskeletons enable paraplegic patients to stand-up and walk again. However, the weight and overall functional performance of the exoskeleton prevents them from being widely used. To reduce the weight and increase the performance, pneumatic actuators can be used as an alternative to the commonly used electromechanical actuators. This thesis presents a new pneumatic actuator design to power a lower limb exoskeleton in daily life activities. The goal of this thesis is to take a step towards the design and development of exoskeletons with reduced weight, increased compliance and that enable paraplegic patients to perform daily life activities. Out of several concepts, a single vane rotary actuator is worked out in more detail and a prototype is manufactured. This actuator is able to generate a peak torque of 96 ± 2 [Nm] at an operating pressure of 12 [bar], has a range of motion of 132 ± 1 [°] and is able to generate a peak angular velocity of 430 ± 5 [°/s] and a peak power of 252 ± 3 [W]. The designed actuator has a width of 165 [mm], a length of 135 [mm], a dept of 54 [mm] and a total mass of 2.3 [kg], but with small changes can be decreased to below 1.6 [kg]. This is the first known pneumatic actuator able to generate sufficient dynamics to power a full mobilization lower limb exoskeleton in daily life activities. It can be concluded that this new design is a promising actuator to be used in lower limb exoskeletons. In further work, the bandwidth of the actuator must be determined accurately.

Background: Last decades myoelectric prostheses have become more usable, functional and reliable. Yet, the cost of myoelectric upper limb prostheses are still a hindering factor of widespread usage of the prostheses. In developing countries, where the demand for prostheses is relatively higher, commercial myoelectric prostheses are out of reach for the majority of amputees because of limited financial resources. Low cost myoelectric prostheses with the aim of use in developing countries are not commercially available at this moment. Objectives: The goal of this study is to develop a functional low cost myoelectric upper limb prosthesis. The developed prosthesis will be tested with standardized and validated test methods, to evaluate if the prosthesis is usable and functional. The Box and Blocks Test (BBT) and the Southampton Hand Assessment Procedure (SHAP) will be used for this purpose. Results: A low cost myoelectric prosthesis prototype was developed in this study; the MyoGrab Hand. The material cost of the prototype was 99.33 euro. The weight of the prosthesis was 352 g. The maximum pinch force of the hand prosthesis was 54.8 N. The MyoGrab Hand was tested by 20 able-bodied participants with BBT and the SHAP. In a first evaluation with ten participants, the prototype proved its functionality with an average score of 17.0 (± 2.2) with the BBT and an Index of Functionality (IoF) of average 41 (± 8.3) with the SHAP. After optimizing the Arduino code structure, the MyoGrab Hand was evaluated again. Ten able-bodied participants carried out the BBT. The average score on the BBT with the optimized MyoGrab Hand was 18.4 (± 2.4). The result of the BBT in the second evaluation was not significantly better than in the first evaluation (t = -1.3, df = 18, p = 0.21). In a durability experiment, critical failure of the prototype occurred after 16539 cycles of opening and closing of the hand. Conclusion: The goal of this study, the development of a functional low cost myoelectric prosthesis, has been achieved. The MyoGrab Hand was evaluated with standardized and validated test methods and proved itself functional. This is one of the first studies that was focused on the functionality, usability and durability of a low cost myoelectric prosthesis. The functionality of the MyoGrab Hand does not equal the functionality of commercial myoelectric prostheses, commercial myoelectric prostheses are more functional. The MyoGrab Hand was able to perform most of the activities of daily life (ADL) tasks in the SHAP, however, carrying out these ADL tasks took longer, as compared to commercial prostheses. This study is a first step in the direction of making a functional myoelectric prosthesis available to larger part of the amputee population with limited financial resources. Future research should focus on a lower weight battery solution, waterproof design and testing in a non-clinical setting.

The operating room and central sterile supply department (CSSD) are two resource-intensive healthcare departments. Reducing the environmental and financial impact of these departments is of great importance in the global debate on sustainability. Removing unnecessary items from instrument trays may provide a partial solution. However, improvements to tray compositions are often time-consuming, not permanent and not using the full reduction potential. This research compares different methods of medical instrument tray optimization and combines different aspects to create a new methodology. Three models compared and evaluated objective and subjective instrument use percentages and different suggestions for tray optimizations. New tray compositions, based on objective use rates, were discussed with the medical specialists and attuned to their requirements. The result was then reviewed by the OR-assistants, before making any final adjustments. This methodology is tested for abdominal instrument trays at the gynaecology department of the Leiden University Medical Center (LUMC). The new trays were evaluated over a test period and missing items were registered during follow-up. Risks to patient safety as a result of missing individual instruments and chances of missing instruments for different reduction methods are discussed and quantified. Mean use rates of the designated instrument sets are 28.4% (SD=6.43%) for open surgery (n=16) and 47.6% (SD=8.16%) for minimally invasive procedures (n=12). A 37% reduction of instruments is reached across three abdominal trays by removing unnecessary items. Weight of the tray contents is reduced by 31%. During the evaluation (n=7 procedures), mean instrument use for abdominal procedures increased from 28.4% (SD=6.43%) to 46.47% (SD=10.96%) after tray optimization. A reduction based on use rates with a 10% cut-off or based on the recommendations of the medical specialists, induces an 8.7% or 3.9% chance of missing any instrument during the procedure, respectively. Tray content reductions based on OR-assistant suggestions and objective use rates with a 0% cut-off are safe, but do not utilize the complete reduction potential. Different tray optimization methods were compared. Use rates were measured in the OR and expert recommendations were discussed in group sessions. A combination of objective use rates and subjective expert considerations can lead to a significant reduction of the amount of unnecessary items in the medical instrument cycle without harming patient safety. Group consensus amongst medical specialists suggests the most radical reduction of instruments on the tray, but increases chances of missing instruments during surgery. Recommendations based on use rates have to be supplemented by reduction efforts based on the clustering of equivalent instruments. Future work should focus on ways to scale reduction efforts to an autonomous hospital-wide system and teach optimization models to mimic human expert input. It should also focus on exact measurements in the CSSD to estimate reductions in costs and CO2-footprint reliably.

The human machine-interface is more important than ever in the field of exoskeletons. Current design approaches lack a way of systematically designing the ergonomics of exoskeletons. Methods with a more pro active approach to ergonomics have to be developed. This thesis extends existing methods by which self aligning mechanisms are created with a systematic approach. A synthesis method is proposed by which all possibilities are synthesized. These possibilities are then excluded based on kinematic requirements on the system. The remaining possibilities are optimized based on ergonomic guidelines to obtain a set of solutions from which the designer can make well founded design choices. A force-deflection analysis was performed on the resulting solutions. This proposed method is applied to a planar passive exoskeleton for the shoulder. The method was successfully applied by using the total link length, reachable workspace, distance to the body and singularity avoidance as objectives for the optimization. Stiffness was added to the joints to obtain the required force-deflection behavior. The resulting objective values were verified by means of a prototype. The test results showed to be within reasonable bounds to verify the method for the planar case. The force-deflection analysis showed results that can be achieved by linear springs. This has to be verified by additional tests. The proposed method can be used as a tool in future exoskeleton design and can be extended with additional objective functions and constraints and can be extended to the three dimensional case.

The goal of this study was to design a maternal phantom model specialized for experiments in which the stresses in the amniotic sac can be determined during fetoscopic procedures. These stresses caused by surgical procedures are believed to be the leading cause of post surgical pre-birth. Measuring these stresses indicates the quality of fetoscopic instruments and surgical procedures. Founded with literature and experiments with amniotic tissue, the requirements for the design of the phantom model were formulated. With these requirements as a framework a design was made which was validated by medical specialists. Measuring the stresses in the amniotic sac failed, therefore measuring the translations of the amniotic tissue was used as a measure of trauma. This proved a success as medical specialists were positive about the design of the phantom model. The findings in this study support the idea that there is a need for a maternal phantom model for the development of fetoscopic procedures. Measuring the translations of the instruments through the amniotic sac is a successful method for indicating trauma. The resulting design showed potential as a training tool as well. The developed phantom model is a successful first step in making a maternal phantom model to contribute to the quality of fetoscopic procedures.

Analyzing the different signaling pathways of cells is key in understanding the basic functions of the cells in all organic systems from algae to humans. Not only do they help solve our questions on how organisms function, they also allow for new cures to be explored. A large variety of these signaling pathways can be influenced by light and can, for example, stimulate or inhibit cell growth. This research thesis introduces a new lab-on-a-chip MEMS device to help with the cell signaling exploration with a focus on optical cell stimulation. From a culture of HeLa cells, the chip is able to separate individual cells into different chambers by means of microfluidics. These microfluidic channels are processed using SU-8 and place each cell above an LED. In total, each chip houses ten LEDs with four different wavelengths ranging from 450 to 850 nm. Each of these LEDs is individually addressable through an Arduino MEGA with a Matlab user interface. After an introduction into cell signaling, the thesis describes how the chip is build up from two silicon wafers and one glass wafer, and explores novel assembly methods like SU-8 wafer bonding and the use of apertures.

Aim: This project aims to design a lightweight, inexpensive and easy to use upper arm prosthesis through improving the design of ARM3D, which is a 3D printed body-powered transhumeral arm prosthesis. This study will cover general shortcomings of body-powered arm prostheses as the weight, cost, amount of parts and limited accessibility of them. This study also focusses on a natural appearance of the prosthetic arm. Results: The improved design of ARM3D is made of six 3D printed and eight non-3D printed parts. It has three Degrees of Freedom (DOF’s), one control cable, a harness both to suspend and control the prosthesis, an active voluntary closing hand, a passive rotating wrist joint and a passive elbow hinge joint. The prosthesis costs €59,68 and weighs 403 g. It takes 3 days, 6 hours and 47 minutes to print and 15 minutes to assemble. The maximum open hand width is 64 mm and the prosthesis needs 15 N of tension force on the control cable to operate. Furthermore, it is possible to paint the prosthetic fingernails and to remove the nail polish. Conclusion: An improved design of the ARM3D prosthesis is presented in this paper. ARM3D is almost entirely 3D printed. It is a lightweight and inexpensive device. A field study is required to gather more information whether the prosthesis is easy to use.

The arrival of highly automated vehicles introduces a new interaction between the vehicle and driver. System limitations during highly automated driving require the driver to be ready to take back control at request. Previous studies on the take-over process concluded that the driver requires a transition period to stabilize vehicle control after resuming manual control. These studies used traded control to instantaneously transfer control back to the driver, causing an abrupt switch in control authority. Therefore, this study explores Haptic Shared Control as a different transition approach. By varying the level of haptic authority, a smooth connection between automation system and driver can be realized. The aim of this study is to investigate if Haptic Shared Control improves the take-over performance compared to the traded control approach. A total of 30 participants drove two trials in a driving simulator, one for each transition approach. Each trial consisted of 10 take-over scenarios divided into two levels of time-criticality. During autonomous driving the participants were engaged in a secondary task. The take-over performance was assessed based on safety performance, lateral vehicle control, controller performance and subjective measures. Results showed a significant decrease in the standard deviation of the lateral position evaluated over the mean trajectory per participant for the Haptic Shared Control approach compared to traded control. Haptic Shared Control also showed a significant decrease for the mean lateral obstacle clearance. The analyses on torque conflicts revealed a significant increase for critical take-over maneuver compared to non-critical take-over maneuvers. This suggests that haptic shared control can assist the driver in stabilizing lateral vehicle control after resuming manual control. On the other hand, the driver is limited in performing a sharp evasive maneuver, and this relationship is discussed. More research is needed on using an adaptable human compatible reference.

Body-powered prosthetic hands used by below-elbow amputees function in two phases. There is the opening and closing motion of the hand (Motion Phase) and the phase when the hand is in contact with an object, and the fingers apply a pinching force (Pinching Phase). Each phase requires a different set of dynamics to properly function. In the Motion Phase, a small amount of applied force must result in a large translation of the fingers, in the Pinching Phase a small amount of force must result in a large pinching force and a small translation. The problem is that body-powered prostheses have fast motion given a low force input during the motion phase but cannot achieve a high pinching force with a low force input during the pinching phase. The goal of the project is to design a mechanism that passively switches between the dynamics of the motion phase and pinching phase for body-powered active closing hook prostheses. In the motion phase a small force input must result in a large output translation and in the pinching phase a small force input must result in a larger force output and a small output translation. In the motion phase a minimum cable force of 10 N is required and in the pinching phase a pinching force of 30 N must be achieved with an input force of 40 N or less The prototype consists of a hydraulic telemanipulation system with a master (shoulder), operated by the shoulder harness, and slave (hand), operates the hand prosthesis, cylinder connected to each other via a booster mechanism. The booster is inactive in the motion phase and active in the pinching phase. The results show that in the motion phase an input force of 5 N can perform the full translation of the prosthesis. If the hand is met with resistance the input 5 N input can increase up to 24 N until the pinching phase activates. The translation in the pinching phase is too small to observe any change. The pinching phase activates at a pinching force of 12 N and an input force of 24 N. In the pinching phase the pinching force reaches 35 N with an input force of 32 N input force. The dynamics of the phases show to be unaffected by different object stiffnesses and lowering the activation force of the pinching phase only shifts the pinching phase along the motion phase. In conclusion the 5 N minimum input force is too low. An input force below 10 N result in inferior control for the user. In the pinching phase an input force of 32 N can reach a pinching force of 35 N, which meets the set requirements of 30 N pinching force with an input force of 40 N or less. A larger translation is required in the pinching phase to compare the translation dynamics between the motion and pinching phase. More research is required to properly define the desired activation force, how much translation is required in the pinching phase, and to find optimal spring properties for the return springs in the hydraulic cylinders.

The project is divided into three sub-assignments: - A future manufacturing context must be envisioned and the most important requirements synthesized. - An implementation of this envisioned manufacturing system must be developed and validated. - An exemplary-product producible by this system must be designed, showcasing the benefits of the envisioned manufacturing method. Envision Following the problem definition and assignment defined in the Introduction phase, the current state of manufacturing and how we got there is analyzed. A future context around a complete product-life-cycle is envisioned. Within this vision both the product as well as the factory are explored. The design tasks were performed in parallel, but they will be described in sequence. First the factory will be discussed: a manufacturing concept is synthesized, the underlying principles are analyzed, and a factory classification is done. Then the exemplary-product will be discussed: the underlying principles of product personalization are explored, and the principles of a product within the developed future context are described. The acquired knowledge gets integrated in a design brief and a list of directing requirements. These form together with the future vision, a starting point to design an actual realization of both product and factory in the phase after the Envision phase. Actualization Following the design brief defined in the Envision phase, the conceptualization of both product and production need to go hand in hand. A realizable future production system must be accompanied by a product that showcases this manufacturing method and the other way around: the personalizable product-family requires a production system that is capable of producing these one-off-products at a high production-capacity. Both design tasks were performed in parallel, but they will be described in sequence in this part of the report. First the exemplary-product will be discussed: the choice, the conceptualization, and the embodiment. Then the Transcended production system will be discussed: the required standardization, the proposed production cluster, conceptualization of the production framework and embodiment of the initial prototype. This prototype can then be used for validation of the propped framework in the phase after the Actualization phase. Validation In the Actualization phase a framework is proposed for the full, so called, pick-and-place on-printing process. This framework should be able to produce the designed computer mouse. And a prototype is developed solving the most important FDM-Cabinet embodiment challenges, resulting in a working system. The goals for this prototype are, firstly to demonstrate an initial framework that is able to produce a personalized consumer electronics product from start to finish at a mass-production output capacity (theoretically). And secondly to validate the pick-and-place on-printing process as a feasible method to produce multi-component parts. The Core Functional Requirements for this prototype are discussed and validated in each of following sub-chapters. The last subchapter validates the Core Functional Requirements for the exemplary-product itself. The research findings will then be used for evaluation in the phase after the Validation phase.

Sentinel lymph node biopsy (SLNB) is a procedure that is used to determine the stage of disease of melanoma patients and determine further treatment. However, the morbidities accompanied with this procedure are not negligible (e.g., wound infection, lymphoedema and seroma). With the goal reduce the incidence of morbidities, this thesis investigated the possibility of minimally invasive sentinel lymph node biopsy (MISLNB). Preceding this thesis, a literature study was written by the writer of this thesis to examine whether there was already a possible solution for this problem. This literature study showed that there are no off the shelf available solutions for MISLNB. Therefore, three solution with the reduction of comorbidities and the importance of extit{en bloc} excision at their core were proposed. These solutions were found through literature, patents, and some ingenuity. The solution with the highest probability was selected to develop further. This concept was then subjected to different experiments to determine whether it was viable option for MISLNB. This study also aimed to fill some of the missing data on the material behaviour of lymph nodes (LN), specifically stress-strain behaviour under compression. By using a set of requirements one solution was selected to be the most viable given the available information. This solution was called the Pull-and-Harvest method. This concept uses a vacuum to grip the sentinel lymph node (SLN) and stash it in a tube, hereafter a snare would cut the lymph ducts and blood vessels. This concept scored well mainly due to the low risk of damaging SLN and its simplicity. The next step was to determine whether this concept was a feasible solution to MISLNB. The problem was divided into three subproblems to estimate this feasibility. The first being the force required to separate the SLN from its surrounding tissue. Since no data on this subject was available a simplified model was created to estimate this value based on the stretch of lymph ducts. The second part of this problem was, determining the force required to stash the SLN inside the tubular volume. Finally, the maximal force of two silicon suction cups was determined. From these experiments several conclusions could be drawn: the conical silicon suction cups used in this study are very inefficient (10%) efficiency) for gripping LNs, these suction cups will stash the LNs but probably not with the additional estimated adherence force and the risk of damaging the LN using a vacuum seems to be low. Based on these observations during these experiments possible ways of were suggested and could make the Pull-and-Harvest a viable procedure. Lastly stress-strain behaviour of LNs could be described using an exponential relationship. This thesis outlines the problem of MISLNB and highlights the areas of interest for further research. However, there is more research and development needed to find a definitive solution for MISLNB.

Background Upper limb prostheses help people with an upper limb deficiency in performing activities of daily living. They can be divided into two categories; body-powered and externally powered prostheses. The advantage of body-powered prostheses is that they provide feedback to the user. The advantage of externally powered prostheses is the low operating force required to control the prosthesis. To reduce rejection rates of upper limb prostheses control, cosmetics and comfort should be improved. To improve control, a design was proposed integrating proprioceptive force feedback into an externally powered upper limb prosthesis with a haptic interface placed on the scapula. However, the cosmetics and comfort are to be improved. The goal of this study is to design a haptic force feedback system that meets the demands regarding comfort and cosmetics. Method Design requirements and mechanical requirements are set. A conceptual design was made using SolidWorks and a prototype was built. The proposed prototype was tested on a test bench to evaluate the overall system. It was analyzed whether the design met the pre-set requirements and the results were compared to other devices. Results The designed haptic device is made out of an anchoring system, pneumatic artificial muscle (PAM), and a distance sensor. The total weight of the system is 41푔 for the anchoring system and PAM, and 29푔 for the distance sensor. The dimensions are 50푥25푥120푚푚. The maximum pressure for the actuator is 3푏푎푟. The output forces reached are 87.41푁, 79.04푁, 100.00푁, 85.38푁, and 104.8푁 for actuators with an initial length of 80푚푚, 90푚푚, 100푚푚, 110푚푚, and 120푚푚 respectively. The designed distance sensor measures a distance up to 58푚푚, with an accuracy of ±1푚푚. Compared to other devices the developed overall system is lighter in weight and smaller in size. Furthermore, it is made out of flexible materials, allowing the device to bend along the curve of the shoulder. Conclusion This study presents a new design for a haptic interface to provide proprioceptive force feedback for an upper limb prosthesis. It is an improvement in cosmetics and comfort, while still meeting the mechanical requirements. Future research should be done with users of an upper limb prosthesis to evaluate the applicability.

Patients who suffer from Duchenne Muscular Dystrophy, have to live with hand impairments for over 15 years. This significantly influences their ability to live independently. Currently, static splinting interspersed with stretching of the hand is the course of treatment for this patient group and developed active hand orthoses focus mainly on stroke and SCI patients. The Symbihand was developed by R. Bos and K. Nizamis in 2019. The active hand orthosis is especially designed to assist DMD patients in ADL. Control is intuitive, the self-aligning mechanism prevents inaccurate joint alignment during flexion and the hydraulic finger modules are forceful and can achieve proper ROM. One of the limitations of the device is that the thumb is restricted to an awkward position in order to facilitate grasping abilities. That while, the thumb is of substantial influence on the versatility of the hand and actuation of this digit could be of additional value for functionality by adding the possibility of the key pinch . This thesis describes the design and evaluation of a thumb module for the Symbihand with the aim to release the awkward static position of the splinted thumb. In order to add a thumb module to the system, preservation of the hydraulic actuation and the self-aligning mechanism is imperative. The design scope of the thumb module becomes as follows: "The design of a hydraulic thumb module for the Symbihand, with the focus on functional assistance of DMD patients who have limited hand function and are wheelchair confined." This can be achieved by assisting the hand in the ROM and force needed for the precision pinch, lateral pinch and cylindrical pinch. It should be taken into account that the addition of a thumb module might complicate control, so added function and diminished ease of control must be in balance. Included in this thesis is a design paper about the thumb module (Section II), a literature study on the fixture design of hand orthoses for DMD patients (Section III) and additional explanations of design choices and requirements in the Appendix.

The elicitation of user engagement is one of the current challenges of human-robot interaction, alongside with the identification of appropriate metrics to evaluate users' experience. Several studies focused on strategies aimed at maintaining engagement throughout an interaction, but limited research has been done on how to initiate it by drawing users' attention. The use of social cues in nonverbal human-human communication has been identified as a reliable source of information to determine if a person is engaged. These social cues can be used not only to understand more about human behavior, but also to design robot behaviors that can successfully draw the attention of humans. In this project we look to investigate what are effective techniques to draw attention and elicit initial engagement with a social robot at the entrance of a building. The robot proposed to display these behaviors is the humanoid robot Pepper, from SoftBank Robotics, as it has been specifically designed for human-robot interaction. Initially, the on-board functionalities of the robot are going to be tested. Secondarily, state-of-the-art techniques are going to extend those functionalities to improve Pepper's interactive skills. Eventually, robot behaviors are going to be designed and displayed to participants during an experiment. We aim at understanding the reactions of people to identify the most effective drawing attention behaviors and examine if the encounter with the robot is affected by a novelty effect. Different metrics are proposed to measure both these phenomena in our results. Our system is developed in Python with features extracted from Pepper's Naoqi framework.

Current wrist prostheses offer limited functionality regarding degrees of freedom and range of motion. A new two degrees of freedom wrist mechanism was designed and based on this concept a prototype was build and tested. Testing included generated torque measurements, externally applied torques, weight and size measurements. The prototype has a 50 mm diameter, stands 68 mm tall and weighs 230 grams. The device is capable of providing active flexion/extension and pronation/supination with approximate output torques of 0.3 and 0.2 Nm respectively. The lack of output torques is most likely caused by the use of a 3D printed housing which resulted in several alignment issues, introducing additional friction into the system. In conclusion the concept provides the desired motion in a relatively compact size, however future work should increase the performance starting by designing a better, preferably non 3D printed, housing.

During endonasal pituitary surgery - an approach of skull base surgery - long slender instruments are inserted through the nose of the patient, in order to remove a pituitary lesion. One of the instruments which is repeatedly used is the surgical punch, which is able to remove pieces of bone in order to create access to the lesion. The drawback of the currently used surgical punches is twofold: first of all, they do not allow for rotation of the tip relative to the handle orientation in order to align the tip properly to the bone to be cut. Furthermore, the successive introduction and extraction of the instrument from the operational area after each cut, increases the risk of introducing bacteria and slows down the procedure. A novel surgical punch was designed and developed called NeuroPunch. Throughout the course of this study, a human-centered design approach combined with a systematic engineering process was followed leading to several conceptual solutions for different functional parts of the NeuroPunch. By combining these conceptual solutions, a design was set for a first functional prototype including an ergonomic handle, a mechanism for the storage of punched bone pieces, and a mechanism for rotating the tip relative to the handle orientation. A first evaluation of the functional 1:1 scale prototype with end users shows positive results indicating that the NeuroPunch might be a proper replacement for the currently used punches in endonasal pituitary surgery. Several iterative steps are required to produce a fully functional prototype of the NeuroPunch which can be evaluated in a preclinical setting (e.g. cadaver study). The NeuroPunch shows much potential to be used for other surgeries as well, and it is demonstrated that the NeuroPunch will enable a safer and more comfortable endonasal pituitary surgery while potentially reducing operating time.

Background Despite its high demand, prostheses are too often abandoned because they fail to meet the main requirements control, comfort and cosmesis. Body-powered hook prostheses provide good control due to their proprioceptive feedback but are in general not efficient nor appealing. The WILMER group has developed an appealing voluntary-opening prehensor by building all mechanical parts inside the prosthetic cover. The voluntary closing (VC) version, the Tweezer, has slight advantages over the voluntary opening but failed to provide sufficient energy transmission within the available space to which hydraulics offer the solution. The objective is to develop and evaluate a hydraulic VC mechanism within a body powered hook prosthesis that meets the main requirements. Methods A hydraulic system was designed. The system shall transmit a 32 N and a 6.4 N actuation force, when holding objects for a prolonged time, to a 7 N pinch force. A maximum 40 mm actuation displacement shall close the hook from a 50° open to a 0° closed position. The system shall fit inside the prosthetic cover and have a maximum mass of 43 g. A prototype was built and tested to measure its performance. Results The design consists of three hydraulic actuators: a master cylinder, a slave cylinder and a pressure intensifier. The user actuates the master cylinder, which is incorporated in the harness, causing fluid to be transferred to a slave cylinder in the prosthesis that closes the hook to grasp objects. When an object is met the pressure intensifier amplifies the pressure of the slave to increase the pinch force to 45 – 53 N and 9 – 11 N for actuation forces 32 and 6.4 N respectively. The actuation displacement equals 26 mm. The prototype failed to be manufactured properly within the given time and a simplified version, equal to the inactive pressure intensifier, has been made to prove part of the concept. Theoretically, the simplified version closes the hook with an actuation displacement of 11 mm and reaches pinch forces of 5 – 6 N over the hook range. The prototype closes the hook with 12 mm and reaches pinch forces 3 – 5 N. It takes 4 N to reopen the hook. The simplified version weighs only 15 g and fits easily inside the prosthetic cover. The mechanism provides proprioceptive feedback at the master cylinder. Conclusion Part of the concept has been proven. Theoretically, by adjusting the simplified versions parameters the 32 N actuation force could generate pinch forces 16 – 19 N with a 34 mm actuation displacement. It would outperform other body powered prostheses in terms of force transmission. The hydraulic VC mechanism has the potential to transfer a comfortable actuation force and displacement into the required pinch force within the available space of the Tweezer. Thus, a voluntary closing hook prosthesis is designed that can satisfy all user requirements control, comfort and cosmesis.