A5054781629- Advanced MEMS and NEMS Technologies
- Mechanical and Optical Resonators
- Geophysics and Sensor Technology
- Magnetic Field Sensors Techniques
- Advanced Sensor and Energy Harvesting Materials
- Advanced Fiber Optic Sensors
- Advanced X-ray Imaging Techniques
- Acoustic Wave Resonator Technologies
- Energy Harvesting in Wireless Networks
- Advancements in PLL and VCO Technologies
- Analog and Mixed-Signal Circuit Design
- Advanced Surface Polishing Techniques
- Particle Detector Development and Performance
- Photonic and Optical Devices
- Tactile and Sensory Interactions
- Inertial Sensor and Navigation
- Particle Accelerators and Free-Electron Lasers
- Advanced Measurement and Metrology Techniques
- Advanced Electron Microscopy Techniques and Applications
- Sensor Technology and Measurement Systems
- Advancements in Photolithography Techniques
- Metal and Thin Film Mechanics
- Pressure Ulcer Prevention and Management
- Force Microscopy Techniques and Applications
- Wireless Power Transfer Systems
International Iberian Nanotechnology Laboratory
2018-2024
Synchrotron soleil
2016-2023
University of Minho
2010-2022
Research Centre in Digitalization and Intelligent Robotics
2019
Polytechnic Institute of Bragança
2019
Universidade Federal do Tocantins
2019
Over the past few years, gap between field-programmable gate array (FPGA) and application-specific integrated circuit (ASIC) performance levels has been narrowed due to constant development of FPGA technology. The high performance, together with lower costs a shorter time market, turns FPGA-based platforms attractive for huge range applications, among them time-to-digital converters (TDCs). It is, therefore, important analyze evolution TDCs better understand where research efforts should be...
In this work a multilevel nanoimprint lithography (NIL) replication process was demonstrated to produce 1D MEMS mirrors employing vertical asymmetric comb-drive electrostatic actuation, in 200 mm wafer SOI-based process. comparison with direct write laser (DWL) grayscale step (which for the proposed layout requires around 40 h of exposure time per wafer), NIL method greatly enhances fabrication throughput by reliably reproducing master's topography onto photoresist. This study describes...
Active Noise Cancellation (ANC) systems are widely used to mitigate unwanted noises in several applications, such as automotive environments and high-end headsets. Multi-Channel (MC) ANC have shown promise creating improved silent zones. Typically, these implemented on FPGA platforms due the systolic nature granularity of optimization devices. This article describes design, implementation, evaluation a wavelet-based MC Filtered-x Normalized Least Mean Square (FxNLMS) an platform. The use...
This work presents a flexible polyimide-based capacitive tactile sensing array with sub-millimeter spatial resolution. The sensor is conceived to be embedded in multimodal artificial finger detect and classify the texture morphology of an object's surface. proposed comprises 16 × units. Each unit composed parallel square electrode pairs (340 μm 340 μm) separated by compressible air cavity into polyimide substrate. Standard MEMS microfabrication techniques were used develop sensor. device was...
Pressure 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 form Smart Health Textiles, which possess innovative properties such thermoregulation, sensing, antibacterial control. This protocol aims to describe process for new type smart clothing individuals with reduced mobility and/or who bedridden order prevent PIs. paper's main purpose is present eight phases project, each...
High-resolution pull-in-based microelectromechanical system (MEMS) inclinometers are presented in this paper. Pull-in is characterized by the sudden loss of stability electrostatically actuated parallel-plate structures, and since pull-in voltage stable easy to measure, it enables an effective transduction mechanism that does not require complex capacitive readout electronics. The MEMS devices used test novel architecture have differential actuation electrodes resulting two voltages change...
An open-source tool that allows for a fast and precise analytical calculation of multi-layer planar coils self-inductance, without any geometry limitation is proposed here. The process designing simulating to achieve reliable results commonly limited on accuracy or geometry, are too time-consuming expensive, thus speed up this design desired. model based Grover equations, valid geometry. validation the was performed through comparison with experimental measurements, Finite Element Model...
This study aimed to evaluate a clothing prototype that incorporates sensors for the evaluation of pressure, temperature, and humidity prevention pressure injuries, namely regarding physical comfort requirements. A mixed-method approach was used with concurrent quantitative qualitative data triangulation. structured questionnaire applied before focus group experts sensor prototypes. Data were analyzed using descriptive inferential statistics discourse collective subject, followed by method...
Several devices and measurement approaches have recently been developed to perform ballistocardiogram (BCG) seismocardiogram (SCG) measurements. The development of a wireless acquisition system (hardware software), incorporating novel high-resolution micro-electro-mechanical (MEMS) accelerometer for SCG BCG signals data treatment is presented in this paper. A small accelerometer, with sensitivity up 0.164 µs/µg noise density below 6.5 µg/ Hz used applications. also incorporates...
An accelerometer based on the electrostatic pull-in time of a microstructure is presented in this paper. The device uses parallel-plate overdamped microstructure, and real-time control operation performed using field programmable gate array high precision digital-to-analog converters. Both open-loop closed-loop measurements are presented. low noise key feature approach, which limited only by mechanical-thermal used, 2 μg/√Hz as shown results (3 operation). readout method has extremely...
Environmental factors, such as pressure and temperature, are known to contribute the formation of ulcers that seriously affect bedridden individuals. Researchers have proposed several technologies achieve long-term monitoring those parameters, usually relying on sensing mats, which poses difficulties in correlating measurements with specific parts body. In this work, we aim develop microsensors be integrated into patient clothing. They should highly flexible, thin a small footprint, can...
Predictive maintenance has been growing as one of the main topics Industry 4.0 concept and several challenges arise from it. The constant search for mechanisms that allow control reduction machine down-time led to study new ways extracting valuable information injection tools through monitorization different parameters. In presented here, a custom pressure sensor is integrated into an tool monitor levels along process cycle, together with commercial off-the-shelf accelerometer, coupled at...
Time-to-Digital Converters (TDC) are popular circuits in many applications, where high resolution time measurements required, for example, Positron Emission Tomography (PET). Besides its resolution, the TDC's linearity is also an important performance indicator, therefore calibration usually play role on TDCs architectures. This paper presents all-digital TDC implemented using Structured Datapath to reduce need circuitry and cells custom design, without compromising linearity. The proposed...
The uniqueness of microelectromechanical system (MEMS) devices, with their multiphysics characteristics, presents some limitations to the borrowed test methods from traditional integrated circuits (IC) manufacturing. Although improvements have been performed, this specific area still lags behind when compared design and manufacturing competencies developed over last decades by IC industry. A complete digital solution for fast testing characterization inertial sensors built-in actuation...
A novel MEMS inclinometer is presented in this paper. The sensor uses the pull-in voltages of microfabricated structures as transduction mechanism enabling a high-resolution, auto-calibrated inclinometer. Pull-in characterized by sudden loss stability electrostatically actuated parallel-plate actuators and since voltage stable easy to measure, it enables an interesting mechanism. microstructures have differential actuation electrodes (with common electrode) resulting two that change...
In this manuscript, the first pyroelectric-based rechargeable electret for continuous energy harvester is reported. The proposed preparation provides two main advantages 1) Wafer-scale production with uniform surface charge density and 2) On-chip option electret-based harvesters sensors. Pyroelectrically generated charges are transferred to dielectric material placed in contact polarized of pyroelectric crystal. A 5 mm thick lithium niobate crystal used as a temperature gradient 2.3°C/sec....
A very high-resolution SOI (silicon-on-insulator) MEMS (Micro-Electro-Mechanical Systems) accelerometer for geodetic space grade applications using pull-in time measurements is presented here. Parallelplates implemented in the handle-layer are used to provide necessary squeeze-film damping, while increasing effective-mass. Large mass (126 mg) devices with low-Q (quality factor of 0.53) have been fabricated and tested transduction. The high measured sensitivity 1.9 ns/ng enables use device...
This paper presents a TDC architecture based on gray code oscillator with improved linearity, for FPGA implementations. The proposed introduces manual routing as method to improve the linearity and precision, by controlling Datapath, which also reduces need calibration mechanisms. Furthermore, procedure improves performance homogeneity across multiple channels, enabling use of same module if further precision is required. channel uses only 16 logic resources (considering Xilinx 7 series...
In this paper, we present a bi-directional extended range parallel-plate electrostatic actuator using feedback linearization control. The can have stable displacements up to 90% of the full-gap (limited by mechanical stoppers) on both directions, i.e., device move ±2μm within ±2.25μm gap. system has successfully tracked references until 1kHz dynamics device) and it presents capacitor tuning 17, an actuation voltage from 0 10V. results presented here are clear advance in respect current...
This work presents a micromachining process that allows the creation of hierarchical, matryoshka-like MEMS structures can be used for multi-axis sensing. novel vibration sensor based on capacitive open-loop operation widely deployed in structural monitoring systems due to its simple fabrication and operating principle. The device is composed by double proof-mass hierarchical design with separate sets electrodes in-plane differential measurements. principle this relies fact accelerations zz...
The field of three-dimensional multi-modal X-ray nanoimaging relies not only on high-brilliance X-rays but also high-precision mechanics and position metrology. Currently available state-of-the-art linear rotary drives can provide 3D accuracy within tens to hundreds nm, which is often insufficient for high resolution imaging with nanofocused beams. Motion errors are especially troublesome in the case rotation their correction more complicated metrology grade reference objects. Here we...