FLEXIBLE TEG ON THE ANKLE FOR MEASURING THE POWER GENERATED WHILE PERFORMING ACTIVITIES OF DAILY LIVING

In this work, a commercial flexible thermoelectric generator (f-TEG) was used to harvest the body thermal energy during the execution of activities of daily living (ADL). The f-TEG was placed at the level of the ankle, and the performed activities were sitting at the desk and walking. In the first stage of measurements, tests were performed to choose the value of the resistor load that maximizes the power output. Then, while performing ADL, the values of generated power were in the range from 100 to 450 µW. Moreover, while users are walking, the pattern of the output signal of f-TEG is compatible to a sine function with frequency close to that one of human gait. This preliminary result may represent a new way to study the movement of human body to recognize AD

Measurements of generated energy/electrical quantities from locomotion activities using piezoelectric wearable sensors for body motion energy harvesting

In this paper, two different piezoelectric transducers—a ceramic piezoelectric, lead zirconate titanate (PZT), and a polymeric piezoelectric, polyvinylidene fluoride (PVDF)—were compared in terms of energy that could be harvested during locomotion activities. The transducers were placed into a tight suit in proximity of the main body joints. Initial testing was performed by placing the transducers on the neck, shoulder, elbow, wrist, hip, knee and ankle; then, five locomotion activities—walking, walking up and down stairs, jogging and running—were chosen for the tests. The values of the power output measured during the five activities were in the range 6 W–74 W using both transducers for each joint.Web of Science164art. no. 52

A MATLAB-BASED GUI FOR REMOTE ELECTROOCULOGRAPHY VISUAL EXAMINATION

In this work, a MATLAB-based graphical user interface is proposed for the visual examination of several eye movements. The proposed solution is algorithm-based, which localizes the area of the eye movement, removes artifacts, and calculates the view trajectory in terms of direction and orb deviation. To compute the algorithm, a five-electrode configuration is needed. The goodness of the proposed MATLAB-based graphical user interface has been validated, at the Clinic of Child Neurology of University Hospital of Ostrava, through the EEG Wave Program, which was considered as “gold standard” test. The proposed solution can help physicians on studying cerebral diseases, or to be used for the development of human-machine interfaces useful for the improvement of the digital era that surrounds us today

Modeling and measurement of an ultrasound power delivery system for charging implantable devices using an AlN-based pMUT as receiver

Ultrasound power delivery can be considered a convenient technique for charging implantable medical devices. In this work, an intra-body system has been modeled to characterize the phenomenon of ultrasound power transmission. The proposed system comprises a Langevin transducer as transmitter and an AlN-based square piezoelectric micro-machined ultrasonic transducer as receiver. The medium layers, in which elastic waves propagate, were made by polydimethylsiloxane to mimic human tissue and stainless steel to replace the case of the implantable device. To characterize the behavior of the transducers, measurements of impedance and phase, velocity and displacement, and acoustic pressure field were carried out in the experimental activity. Then, voltage and power output were measured to analyze the performance of the ultrasound power delivery system. For a root mean square voltage input of approximately 35 V, the power density resulted in 21.6 mu W cm(-2). Such a result corresponds to the data obtained with simulation through a one-dimensional lumped parameter transmission line model. The methodology proposed to develop the ultrasound power delivery (UPD) system, as well as the use of non-toxic materials for the fabrication of the intra-body elements, are a valid design approach to raise awareness of using wireless power transfer techniques for charging implantable devices.Web of Science1312art. no. 212

Evaluation of an electro-pneumatic device for artificial capillary pulse generation used in a prospective study in animals for surgical neck wound healing

The paper examines the development and testing of an electro-pneumatic device for wound healing therapy after surgery in the neck area. The device generates air pressure values in a miniaturized cuff using electronic circuitry to drive an electro-valve and air compressor. The device works in two distinct modes: continuous pressure mode and pulsating pressure mode. The pressure value setting can vary from 3 to 11 mmHg, and the pulsating pressure mode's operating frequency range is approximately 0.1 to 0.3 Hz. Laboratory measurements were conducted to evaluate the device's correct functioning in both continuous and pulsating pressure modes. A four-day prospective study with animals (n = 10) was also conducted to evaluate neck wound healing therapy using the electro-pneumatic device. Out of the twelve histological parameters analysed to reveal the differences between the experimental and control wounds, only one demonstrated a significant difference. Out of the ten animals treated with the device, three showed a significant difference in terms of benefit after therapy. We can therefore conclude that the device potentially improves the wound healing process in the neck area if the pre-set air pressure value does not exceed 8 mmHg.Web of Science9art. no. 983

Plethysmography system to monitor the jugular venous pulse: A feasibility study

Cerebral venous outflow is investigated in the diagnosis of heart failure through the monitoring of jugular venous pulse, an indicator to assess cardiovascular diseases. The jugular venous pulse is a weak signal stemming from the lying internal jugular vein and often invasive methodologies requiring surgery are mandatory to detect it. Jugular venous pulse can also be extrapolated via the ultrasound technique, but it requires a qualified healthcare operator to perform the examination. In this work, a wireless, user-friendly, wearable device for plethysmography is developed to investigate the possibility of monitoring the jugular venous pulse non-invasively. The proposed device can monitor the jugular venous pulse and the electrocardiogram synchronously. To study the feasibility of using the proposed device to detect physiological variables, several measurements were carried out on healthy subjects by considering three different postures: supine, sitting, and upright. Data acquired in the experiment were properly filtered to highlight the cardiac oscillation and remove the breathing contribution, which causes a considerable shift in the amplitude of signals. To evaluate the proper functioning of the wearable device for plethysmography, a comparison with the ultrasound technique was carried out. As a satisfactory result, the acquired signals resemble the typical jugular venous pulse waveforms found in literature.Web of Science1112art. no. 239

USING PVDF FILMS AS FLEXIBLE PIEZOELECTRIC GENERATORS FOR BIOMECHANICAL ENERGY HARVESTING

In this paper, a commercial polymeric piezoelectric film, the polyvinylidene fluoride (PVDF) was used to harvest electrical energy during the execution of five locomotion activities (walking, going down and up the stairs, jogging and running). The PVDF film transducer was placed into a tight suit in proximity of four body joints (shoulder, elbow, knee and ankle). The RMS values of the power output measured during the five activities were in the range 0.1 – 10 µW depending on the position of the film transducer on the body. This amount of electrical power allows increasing the operation time of wearable systems, and it may be used to prolong the monitoring of human vital signals for personalized health, wellness, and safety applications

Real time event-based segmentation to classify locomotion activities through a single inertial sensor

We propose an event-based dynamic segmentation technique for the classification of locomotion activities, able to detect the mid-swing, initial contact and end contact events. This technique is based on the use of a shank-mounted inertial sensor incorporating a tri-axial accelerometer and a tri-axial gyroscope, and it is tested on four different locomotion activities: walking, stair ascent, stair descent and running. Gyroscope data along one component are used to dynamically determine the window size for segmentation, and a number of features are then extracted from these segments. The event-based segmentation technique has been compared against three different fixed window size segmentations, in terms of classification accuracy on two different datasets, and with two different feature sets. The dynamic event-based segmentation showed an improvement in terms of accuracy of around 5% (97% vs. 92% and 92% vs. 87%) and 1-2% (89% vs. 87% and 97% vs. 96%) for the two dataset, respectively, thus confirming the need to incorporate an event-based criterion to increase performance in the classification of motion activities

A Mechatronic Cardiovascular Simulation System for Jugular Venous Echo-Doppler Training

Echo-doppler examination of the jugular vessel is a powerful tool for the early diagnosis of cardiovascular disorders that can be further related to central nervous system diseases. Unfortunately, the ultrasound technique is strongly operator-dependent, so the quality of the scan, the accuracy of the measurement, and therefore the rapidity and robustness of the diagnosis reflect the degree of training. The paper presents the development of a mechatronic simulation system for improving the skill of novice physicians in echo-doppler procedures. The patient is simulated by a silicone manikin whose materials are designed to have a realistic ultrasound response. Two tubes allow blood-mimicking fluid to flow inside the manikin, simulating the hemodynamics of the internal jugular vein. The mechatronic system is designed for controlling the flow waveform, to reproduce several clinical cases of interest for diagnosis. The experiments investigate the accuracy of the echo-doppler measurements performed on the proposed system by novice operators using a real ultrasound scanner

Drain Brain: monitorare il drenaggio cerebrale negli astronauti per prevenire problemi cardiovascolari

Un importante obbiettivo della ricerca spaziale internazionale, in preparazione all'esplorazione umana della Luna e di Marte, è quello di tutelare la salute degli astronauti. Il volo spaziale induce importanti alterazioni a carico di diversi sistemi fisiologici e queste risposte adattative inducono un generale decondizionamento dell'organismo. I programmi di ricerca medica hanno lo scopo di assicurare la salute degli astronauti che affronteranno viaggi spaziali oltre l'orbita bassa, permetterne la pronta operatività una volta arrivati a destinazione e consentirne un sicuro recupero al rientro sulla Terra. Fra i programmi messi in campo dall'Agenzia Spaziale Italiana (ASI), gli esperimenti denominati Drain Brain, svolti in collaborazione con l'Università di Ferrara, sono particolarmente esemplificativi da questo punto di vista. Il progetto, iniziato con la collaborazione di Samantha Cristoforetti nel 2014, ha permesso di dimostrare il funzionamento di un pletismografo per lo studio del circolo cerebrale ed il ritorno venoso dall'encefalo al cuore in condizioni di microgravità. Nei prossimi due anni, grazie al progetto Drain Brain 2.0, gli equipaggi della Stazione Spaziale Internazionale verranno studiati con una nuova versione del sensore pletismografico, sincronizzato con l'elettrocardiogramma, per valutare l'efficienza cardiaca ed il drenaggio cerebrale in rapporto a sintomi come vista offuscata, intorpidimento, annebbiamento o il temuto insorgere di una trombosi giugulare, legata al rallentamento del flusso per assenza del gradiente gravitazionale. Drain Brain 2.0 genererà anche importanti ritorni a Terra, chiudendo il circolo virtuoso dell'applicazione terrestre della ricerca condotta nello Spazio. La nuova strumentazione è di fatto ideale per un uso in telemedicina su pazienti cardiopatici o con problemi cognitivi