Encontrados 12 documentos, a visualizar página 1 de 2
Fabrication and electrical characterization of low-temperature polysilicon film...
Mota, Filipa C.; Garcia, Inês S.; Retolaza, Aritz; Santos, Dimitri E.; Sousa, Patrícia C.; Aguiam, Diogo E.; Dias, Rosana A.; Calaza, CarlosThe development of low-temperature piezoresistive materials provides compatibility with standard silicon-based MEMS fabrication processes. Additionally, it enables the use of such material in flexible substrates, thereby expanding the potential for various device applications. This work demonstrates, for the first time, the fabrication of a 200 nm polycrystalline silicon thin film through a metal-induced crysta...
Development of smart clothing to prevent pressure injuries in bedridden persons...
Rêgo, Anderson da Silva; Furtado, Guilherme Eustáquio; Bernardes, Rafael A.; Santos-Costa, Paulo; Dias, Rosana A.; Alves, Filipe S.; Ainla, AlarPressure injuries (PIs) are a major public health problem and can be used as quality-of-care indicators. An incipient development in the field of medical devices takes the form of Smart Health Textiles, which can possess innovative properties such as thermoregulation, sensing, and antibacterial control. This protocol aims to describe the process for the development of a new type of smart clothing for individual...
End-user assessment of an innovative clothing-based sensor developed for pressu...
Rêgo, Anderson S.; Filipe, Luísa; Dias, Rosana A.; Alves, Filipe S.; Queiroz, José; Ainla, Alar; Arruda, Luísa M.; Fangueiro, Raúl; Bouçanova, MariaThis study aimed to evaluate a clothing prototype that incorporates sensors for the evaluation of pressure, temperature, and humidity for the prevention of pressure injuries, namely regarding physical and comfort requirements. A mixed-method approach was used with concurrent quantitative and qualitative data triangulation. A structured questionnaire was applied before a focus group of experts to evaluate the se...
SU-8 based waveguide for optrodes
Pimenta, Sara Filomena Ribeiro; Ribeiro, J. F.; Gonçalves, Sandra Beatriz Tomé; Maciel, Marino Jesus Correia; Dias, Rosana A.; Gaspar, JoãoNeural probes can be equipped with light for optogenetics applications. Different approaches are used for delivering light to the tissue: an optical fiber coupled to the probe, a µLED or a waveguide integrated on the probe. Small probe dimensions, adequate optical power for photostimulation and good tissue penetration for in-vivo experiments are critical requirements. Thus, integrating a waveguide is a promisin...
Novel magnetic readout for hybrid spintronic MEMS devices
Dias, Rosana A.; Moreira, Eurico Esteves; Ribeiro, Igor; Costa, Margaret; Fonseca, Helder; Cardoso, Susana; Freitas, PauloThis digest reports for the first time on the concept, fabrication and characterization of a spintronics magnetic readout for hybrid MEMS. The method uses magnetic sensors (spin valves) and permanent magnets (on both the movable and the fixed parts of the MEMS structure) to detect displacement. The use of such transduction method has several potential advantages: it allows a small form factor, straightforward r...
FPGA controlled MEMS inclinometer
Alves, F. S.; Dias, Rosana A.; Cabral, Jorge; Rocha, Luís A.; Monteiro, João L.A FPGA (Field Programmable Gate Array) controlled inclinometer based on MEMS structures is presented in this paper. Pull-in voltage measurements are used in this work as the transduction mechanism. The pull-in phenomenon is characterized by the sudden loss of stability in electrostatically actuated parallel-plate actuators and since pull-in voltage is stable and easy to measure, it enables an interesting transd...
Pull-in MEMS Inclinometer
Alves, F. S.; Dias, Rosana A.; Cabral, Jorge; Rocha, Luís A.A novel MEMS inclinometer is presented in this paper. The sensor uses the pull-in voltages of microfabricated structures as the transduction mechanism enabling a high-resolution, auto-calibrated inclinometer. Pull-in is characterized by the sudden loss of stability in electrostatically actuated parallel-plate actuators and since pull-in voltage is stable and easy to measure, it enables an interesting transducti...
Closed loop operation of time-based accelerometers
Dias, Rosana A.; Wolffenbuttel, R. F.; Cretu, E.; Rocha, Luís A.In this paper we present a method for closed-loop operation of pull-in time accelerometers. Accelerometers based on the measurement of the pull-in time of movable parallel-plates MEMS structures have already demonstrated very good resolution capabilities, with low requirements on the capacitive readout. However, open-loop operation delivers very low dynamic range and highly non-linear response. The closed-loop ...
Autonomous MEMS Inclinometer
Alves, F. S.; Dias, Rosana A.; Cabral, Jorge; Rocha, Luís A.Pull-in voltage measurements are used in this work as the transduc-tion mechanism to build a novel microelectromechanical system (MEMS) incli-nometer. By successively bringing the microstructure to pull-in while measur-ing the pull-in voltage allows the detection of external accelerations. Moreover, the availability of asymmetric pull-in voltages that depend on the same mechan-ical structure and properties enab...
Closed-loop operated time-based accelerometer
Dias, Rosana A.; Macedo, Pedro; Silva, Hélder D.; Wolffenbuttel, R. F.; Cretu, E.; Rocha, Luís A.A high-resolution, high dynamic range capacitive accelerometer based on pull-in time measurement is described in this paper. The high sensitivity of pull-in time can be used to implement high performance accelerometers, but non-linearity and low dynamic range compromise device performance. A closed-loop approach using an electrostatic actuation mechanism to control the duration of the pull-in time is presented,...