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Diabetes is a rapidly growing disease, with important complications that decrease the quality of life of patients. Diabetic Foot Ulceration is a major complication of diabetes and can lead to gangrene and amputation. It is related to high pressure developed on the plantar surface and can be prevented and treated with pressure offloading footwear. Current solutions are either mechanic insoles and shoes or smart devices that perform only plantar pressure measurements. This paper presents the design of a device that performs pressure offloading using magnetorheological fluids. The device consists of a magnetorheological valve that controls the offloading and a force sensor. An electronic board is used for force measurements and control of the valve. The experimental results validate the offloading capabilities of the device. Due to their size, multiple such devices, and the electronic board, can be integrated into diabetic footwear to achieve active offloading.

This work presents the electromagnetic design of a 3D-printed winding for a coreless linear motor. The key geometric parameters are optimized with motor constant as the objective. The optimization is applied to two types of coil layouts. An increase of the motor constant up to +26% is observed for the optimized coils compared with the original ones. Several units of the two types of coils are 3D-printed in aluminum alloy and electrically characterized. A glider prototype is assembled and ready for additional tests evaluating experimentally the motor constant in order to be compared to simulations.

Bluetooth Low Energy (BLE) has become very common for tracking applications in homes, stadiums, malls, and hospitals over the last decade. With the outbreak of COVID, the technology was widely used for local tracking of the virus spread [1]. However, despite broad interest in using BLE as a tracker, the primary method is based on Received Signal Strength Indication (RSSI) measurements. On the other hand, the previous studies have demonstrated that this method is prone to multi-path and is inaccurate. With the introduction of BLE Direction Finding a shift in localization method has occurred. With the introduction of BEL direction finding, indoor tracking has come closer to its ultimate goal of asset tracking and positioning in crowded indoor environments. In this paper we present a new fast switching antenna array specifically designed for BLE direction finding. Using our newly designed antenna array and switch, we reached to accuracy of approximately 5° degrees.

Coreless electric motors are gaining interest from the community as they have a larger power-to-weight ratio and a larger efficiency. The absence of iron slots leaves the winding space unobstructed. This enables the geometry of the coils to be skewed to overlap with their neighbors. Such arrangement provides better motor constant. This work proposes to establish some groundwork for the topology optimization of overlapping winding in multi-phase coreless motors. A 2.5D formulation of the density-based approach is proposed to enable the designed coils to span over two layers and spatially overlap with their neighbors, while keeping a limited computational cost. A novel interpolation scheme is also proposed to account for multi-phase winding while only designing one phase.

Soft Magnetic Composites (SMCs) have huge application potential in electrical devices. With the development of additive manufacturing (AM), the properties of SMCs can be boosted. It is therefore required an optimization algorithm to design SMCs considering the AM capacity. Since the magnetic and loss properties of SMCs are highly sensitive to the shape evolution of the components, we introduce a topology optimization approach with integer programming. At each iteration, the components of the composite are determined with crisp boundary. This optimization algorithm converges rapidly because of the topology gradient and the optimal topology is reached.

Magnetic manipulation is a method used for biomedical applications to remotely control micro-robots in a contactless manner. The electromagnet manipulator should control a magnetic field with 3 degrees of freedom inside a region of interest. In various case studies, this field is the result of the superposition of three decoupled uniform magnetic fields. Each of them is individually generated by a different pair of Helmholtz coils. Such arrangement requires the pairs to be nested within each other, inevitably reducing the size of the working area, degrading the performance and the integration of the whole system. The proposed work aims to design a novel electromagnetic manipulator with the help of computational design, to explore beyond the Helmholtz coils arrangement. A topology optimization framework is developed for this purpose. It investigates the distribution of coils that achieves the largest working area, while keeping the different degrees of freedom balanced.

Facial paralysis is a challenging condition that alters a patient's ability to express emotion and communicate. Restoring facial movements thus has crucial implications for the patients' quality of life. This publication introduces an approach for artificial muscles implementation targeting facial reanimation, as well as the challenges and limitations of the proposed strategy. The aim is to develop a Dielectric Elastomer Actuator (DEA) prosthesis for patients suffering from facial paralysis. DEAs are chosen as they are soft, have large strain (up to 200%) and high dynamic behaviour (up to 20 kHz), making them a promising actuator for the application. Myoelectric signals are extracted using electromyography sensors from the Zygomaticus Major muscle, and they are processed in order to emphasize the activation phases. The resulting actuating signal is used to control a high voltage power supply to operate the DEA in an open loop. The resulting induced movement qualitatively matches the myoelectric signal, showing great potential of the proposed approach for facial paralysis reanimation.

Although heart transplant is the preferred solution for patients suffering from heart failures, cardiac assist devices remain key substitute therapies. Among them, aortic augmentation using dielectric elastomer actuators (DEAs) might be an alternative technological application for the future. The electrically driven actuator does not require bulky pneumatic elements (such as conventional intra-aortic balloon pumps) and conforms tightly to the aorta thanks to the manufacturing method presented here. In this study, the proposed DEA-based device replaces a section of the aorta and acts as a counterpulsation device. The feasibility and validation of in vivo implantation of the device into the descending aorta in a porcine model, and the level of support provided to the heart are investigated. Additionally, the influence of the activation profile and delay compared to the start of systole is studied. We demonstrate that an activation of the DEA just before the start of systole (30 ms at 100 bpm) and deactivation just after the start of diastole (0-30 ms) leads to an optimal assistance of the heart with a maximum energy provided by the DEA. The end-diastolic and left ventricular pressures were lowered by up to 5% and 1%, respectively, compared to baseline. The early diastolic pressure was augmented in average by up to 2%.