196,082 research outputs found
Flexible teg on the ankle for measuring the power generated while performing activities of daily living
No full textIn 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 ADL
Nanogenerators for Human Body Energy Harvesting
No full textHumans generate remarkable quantities of energy while performing daily activities, but this energy usually dissipates into the environment. Here, we address recent progress in the development of nanogenerators (NGs): devices that are able to harvest such body-produced biomechanical and thermal energies by exploiting piezoelectric, triboelectric, and thermoelectric physical effects. In designing NGs, the end-user's comfort is a primary concern. Therefore, we focus on recently developed materials giving flexibility and stretchability to NGs. In addition, we summarize common fabrics for NG design. Finally, the mid-2020s market forecasts for these promising technologies highlight the potential for the commercialization of NGs because they may help contribute to the route of innovation for developing self-powered systems
Modeling and Measurement of an Ultrasound Power Delivery System for Charging Implantable Devices Using an AlN-Based pMUT as Receiver
No full textUltrasound 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
Measurement system for classification of hand's gesture
No full textThe goal was to create precise hardware that would be able to measure signal of myopotentials from defined area of forearm for the computer analysis without external noise and with right amplification. The second goal was to program an algorithm which could classify specific gestures of hand based on an analy17sis of myopotencial signals. The computer software was programmed in C# programming language. Signal processing and drawing to user interface was in real time. The one of five possible gestures that user made was analysed by using fuzzy logic and designed system of scaling. It was developed fuzzy classification which is able to recognize gestures with high accuracy
Consumer perceptions on smart wearable devices for medical and wellness purposes
No full textThis study examined Smart Wearable Devices (SWDs) in the form of smartwatches, fitness trackers, smart textiles and jewelry for medical and wellness purposes in the IoT era. Forty-five volunteers participated in a semi-structured interview. The data collected from respondents was used to study consumer perceptions of SWDs. Although many of the participants in the study had heard of SWDs, almost none knew what Body Sensor Networks (BSNs) were. An investigation was also conducted to find a solution to the problem of abandoning the use of SWDs. In the results, many respondents stated a 'real need' for the device as the most important feature for not abandoning it. Some of the smartwatches, fitness trackers, smart textiles and jewelry exhibited at CES 2019 - Las Vegas were listed in the text to highlight the advances in the SWD market. In the authors' opinions, very important steps forward have been made with smart jewelry
Human body energy harvesting solutions for wearable technologies
No full textThe paper presents an overview of recent and noninvasive technologies used to harvest electrical energy on the surfaces of human body. New electronic materials developed to provide sufficient comfort for the people wearing them are analyzed, and an inventory of common sensors for monitoring applications, which can profit from these technologies, is provided. In this way, a comprehensive panorama of what is currently available to design ultra-low-power systems is given. The purpose of the paper is to provide the basis for the development of non-invasive wearable devices, powered by the energy harvested on the surfaces of human body, which consider wearability and comfort constraints
Human body energy harvesting solutions for wearable technologies
No full textThe paper presents an overview of recent and noninvasive technologies used to harvest electrical energy on the surfaces of human body. New electronic materials developed to provide sufficient comfort for the people wearing them are analyzed, and an inventory of common sensors for monitoring applications, which can profit from these technologies, is provided. In this way, a comprehensive panorama of what is currently available to design ultra-low-power systems is given. The purpose of the paper is to provide the basis for the development of non-invasive wearable devices, powered by the energy harvested on the surfaces of human body, which consider wearability and comfort constraints
An Artificial Heart System for Testing and Evaluation of Cardiac Pacemakers
No full textThe usability assessment of a pacemaker is a complex task where the dedicated programmer for testing programmed algorithms is necessary. This paper provides the outcomes of development and complex testing of the artificial cardiac system to evaluate the pacemaker’s functionality. In this work, we used the modular laboratory platform ELVIS II and created graphical user interface in LabVIEW programming environment. The electrical model of the heart allows signals generation (right atrium, right ventricle) and the monitoring of the stimulation pulses. The LabVIEW user interface allows to set the parameters of the generated signals and the simulation of the cardiac rhythm disorders as well as the monitoring and visualization of the pacemaker behavior in real-time. The results demonstrate the capability of proposed system to evaluate the paced and sensed pulses. The proposed solution allows the scientists to test the behavior of any cardiac pacemaker for its pre-programmed settings and pacing mode. In addition, the proposed system can simulate various disorders and test cardiac pacemakers in different working modes
A Flexible Thermoelectric Generator Worn on the Leg to Harvest Body Heat Energy and to Recognize Motor Activities: A Preliminary Study
No full textWearable devices are commonly used to monitor human movement since motor activity is a fundamental element in all phases of a person's life. Patients with motor disorders need to be monitored for a prolonged period and the battery life can be a limit for such a goal. Here the technique of harvesting energy from body heat to supply energy to wearable devices is investigated. A commercial flexible thermoelectric generator, equipped with an accelerometer, is placed on the lower leg above the ankle. The accelerometer serves to detect diverse motor activities carried out by ten students of VSB-Technical University of Ostrava involved in the execution of two tasks. To summarize, the motor activities analyzed in the proposed work are: 'Sit', 'Walk', 'Rest', 'Go biking', 'Rest after biking', and 'Go down and up the stairs'. The maximum measured value of power density was 20.3μW cm-2 for the 'Walk' activity, corresponding to a gradient of temperature between the hot and cold side of the thermocouples constituting the flexible thermoelectric generator of 1.5 °C, while the minimum measured value of power density was 8.3μ W cm-2 for the 'Sit' activity, corresponding to a gradient of temperature of 1.1 °C. Moreover, a mathematical model was developed for the recognition of motor activities carried out during the execution of the experiments. As a preliminary result, it is possible to state that semi-stationary parts of the signal generated by the thermoelectric generator can be traced back to the performance of an activity
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