The measurement of vital signs is a risk-free, inexpensive, and reproducible clinical practice that enables identification of physiological deterioration of patients before an adverse event occurs. However, studies show that manual clinical measurements of respiratory rate are intermittent, biased, and inaccurate. Therefore, a contactless planar capacitive sensor was developed and evaluated against a clinical reference method. Results show that the sensor is accurate (i.e. strong agreement with an average ICC value of 0.99 and an average BSI coefficient of 2.76 < 4 breaths/min clinical threshold) and unbiased (i.e. average mean difference of -0.02 breaths/min). The sensor has promise for respiratory rate monitoring of bedridden patients even during shallow breathing. Future work includes addressing technology limitations, conducting a clinical pilot with a diverse patient population, and exploring potential in sleep quality assessment.

The measurement of vital signs is a risk-free, inexpensive, and reproducible clinical practice that enables identification of physiological deterioration of patients before an adverse event occurs. However, studies show that manual clinical measurements of respiratory rate are intermittent, biased, and inaccurate. Therefore, a contactless planar capacitive sensor was developed and evaluated against a clinical reference method. Results show that the sensor is accurate (i.e. strong agreement with an average ICC value of 0.99 and an average BSI coefficient of 2.76 < 4 breaths/min clinical threshold) and unbiased (i.e. average mean difference of -0.02 breaths/min). The sensor has promise for respiratory rate monitoring of bedridden patients even during shallow breathing. Future work includes addressing technology limitations, conducting a clinical pilot with a diverse patient population, and exploring potential in sleep quality assessment.

This thesis describes a finite element analysis (FEA) model of an indirect heating thermal actuator. The heat transfer mechanisms are investigated and the conductive heat transfer is found to be the dominant heat transfer mode. A model simplification method is discussed and used in the analysis to reduce the degrees of freedom and avoid meshing failures. The device is fabricated with the MetalMUMPs process. Measurements of the displacement as a function of the driving voltage are made to verify the FEA model. The results show that the simulation result of the FEA model produced a reasonable agreement with the experimental data. The difference between the FEA result and test result is investigated. A novel thermal actuator with integrated capacitive position sensor is also investigated. This new thermal actuator with an integrated capacitive sensor uses the indirect heating thermal actuator discussed in the first part of the thesis to achieve a new integration method. The displacement of the actuator provided by the sensor enables a feedback control capability. The analytical model, FEA and test results for the capacitive sensor are presented to validate the design concept. The test results show a reasonable agreement with the analytical analysis and the FEA. Finally, a manual displacement tuning application and a PI feedback control application with the designed thermal actuator with integrated capacitive sensor are documented. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-07-03 16:17:02.633

The presented PhD thesis aims to verify the possibilities of using capacitive accelerate sensors on the crane and handling technology. Capacitive acceleration sensors of MEMS type are currently widely used in electronics, e.g. laptops and mobile phones. Using these sensors could help to automate cranes, which would eventually reduce the financial costs of material handling. Precise knowledge of their own condition and position of the machine and the load is a necessary part of autonomous manipulators. The first part of thesis deals with the exploration of scientific research in the Czech Republic and abroad. Furthermore the options of mathematical description of moving the load on the rope tow are described including solved examples. One chapter is devoted to the description of sensors that could be used in the automation of cranes. The main part is focused on description of several experiments. The experiments were conducted in a lab constructed specially for this measurement. Mainly basic simpler models are described illustrating abilities of the sensor. The last part outlines further possible progress of research in this area.

Water is an important parameter for crop growth, and the information about the moisture content in soil at different depths is very useful for farmers to determine the best time to water the soil and to irrigate farmland so as to maximize their yield. This thesis project aims to develop a prototype of a multi-depth moisture sensor probe that is part of a large sensing system used in agriculture. The sensor probe has three sets and is required to last for 6-12 months of usage and to be reproduced at a low cost. The sensor probe consists of three sensor boards, on each of which has two different capacitive based sensors and one analog temperature sensor. The three boards are placed approximately 20 cm from each other in the probe. During this project, the two capacitive based sensors were developed, one with arc-shaped plates operating at a frequency less than 1 MHz, and one with electrodes in the form of annular rings operating at a high frequency, approximately 100 MHz. The moisture content in the soil is calculated based on the measurement of the frequency, which depends on the dielectric constant of the soil. For the implementation of the sensor probe, three printed circuit boards (PCBs) for the sensor boards were designed using Altium Designer and then ordered; an STM32 Nucleo board with low power microcontroller was used and the software was implemented in STM32CubeIDE. The lifetime of the sensor probe was calculated for different duty-cycles. With a duty-cycle of 15 minutes, where the sensor probe is active for 1 minute and in sleep mode for 14 minutes, the lifetime of the sensor probe would only be 16 days. With a duty-cycle of 120 minutes instead, with the sensor probe being active for 1 minute, the lifetime is increased to 130 days (less than4,5 months). Due to challenges with the high frequency capacitive sensor, the multi-depth sensor probe does not fully work, and thus cannot be tested with a large testbed. Further work needs to be conducted on the high frequency capacitive sensor and the communication with the gateway.

Approved for public release, distribution is unlimited / 100 m/s). Low voltage electrical contact was not maintained for some experimental shots and non-parallel rails were the suspected cause. In this thesis, we used a non-contact capacitive sensor to determine rail spacing to within 2/kAcm10mael, so that the rails will be parallel within small tolerances. Several rails were used in these experiments: 75-25 copper-tungsten, chromium-plated 75-25 Cu-W, and chromium-plated pure copper rails. Improving the control of rail spacing and parallelity did not ensure low-voltage electrical contact for our configurations. The largest damage was observed for chromium-plated copper rails and the least damage occurred for chromium-plated 75-25 Cu-W rails. / Lieutenant, United States Navy

The electrostatic actuation with its several advantages is the main principle for micro-electro-mechanical systems (MEMS). One major drawback is the nonlinear behavior, which results into instability, known as the electrostatic pull-in effect. This effect might also push a closed-loop configuration into instability and thus makes a linear time-invariant control inapplicable to the system. The paper investigates the stability of an acceleration sensor in closed-loop operation with this setting. A simplified controller adjustment gives a first insight into this topic. Practical implementations saturate on the quantizer's full-scale value, which is also considered in the stability analysis. Numerical phase-plane analysis verifies the stability and shows further surprising results.

Este trabalho teve por objetivo desenvolver um sistema de controle em malha fechada em sistema de irrigaÃÃo localizada, visando controlar o processo de irrigaÃÃo. O sistema foi implantado no PerÃmetro Irrigado do Baixo AcaraÃ, em uma Ãrea de 1,0 ha, cultivada com melancia, dividida em quatro subÃreas, onde foram instalados trÃs sensores capacitivos de umidade em trÃs profundidades (0,15m, 0,30m e 0,45m), sendo o sensor de 0,15m conectado a um controlador lÃgico programÃvel (CLP), responsÃvel pelo acionamento das vÃlvulas e pela aceleraÃÃo/desaceleraÃÃo do inversor de frequÃncia, de acordo com o nÃmero de vÃlvulas acionadas simultaneamente. Os sensores nas demais profundidades foram utilizados para monitorar a umidade do solo ao longo do perfil. A partir das leituras dos sensores capacitivos convertidas em umidades em base de volume e atravÃs de uma equaÃÃo de calibraÃÃo, definiu-se o parÃmetro inicial de capacidade de campo do solo (CC), em 20%, como o set point (target) de controle. Os tratamentos foram 820, 795 e 795 Hz, para as estaÃÃes E1, E2 e E4, respectivamente, para o acionamento da motobomba e 732, 714 e 751 Hz para desligar o sistema. Na segunda etapa os parÃmetros de controle foram 784 e 795 Hz para as estaÃÃes E1 e E2, respectivamente, para acionamento da motobomba e 751 e 762 Hz para desligar o sistema. Verificou-se que o sistema apresentou desempenho satisfatÃrio, mantendo a umidade do solo nos nÃveis com elevada frequÃncia de irrigaÃÃo. / This work aims to develop a closed loop control system in a drip irrigation system, aimimg to control irrigation process. The system was deployed in &#8203;&#8203;Low Acaraà Irrigation District (DIBAU) in an area of 1.0 ha, planted with watermelon, divided into four sub0areas, with three capacitive sensors for soil moisture installed at three depths (0.15 m, 0.30 m and 0 were installed , 45m.The sensor was 0.15 m connected to a programmable logic controller (PLC), for driving the valves and the acceleration / deceleration the motor by a frequency converter according to the number of actuated valves simultaneously. The sensors other depths were used to monitor soil moisture along the profile. Using predefined calibration equations, the readings of the capacitive sensors in Hertz were convertd to volume based soil moisture and following initial parameters defined: field capacity soil (CC), at 20%, as the set point (target) of control,conrolling treatments of 820, 795, and 795 Hz, for plots E1, E2 and E4, respectively, to activate the pump, and 732, 714, and 751 Hz to turn the pump off. In a second stage, control parameters were 784 and 795 Hz for stations E1 and E2, respectively, to activate the pÃmp and 751 Hz and 762 to turn off the system. The control systems sucessfully controlled soil moisture, maintaining soil moisture at derired levels with a high frequency of irrigation. From the readings of capacitive sensors converted into moisture on a volume basis and through a calibration equation, we defined the initial parameter of soil to drive the pump and 751 and 762 Hz to shutdown. It was found that the system showed satisfactory performance, maintaining soil moisture levels at high frequency irrigation.

A large-area electronics (LAE) strain sensor, termed soft elastomeric capacitor (SEC), has shown great promise in fatigue crack monitoring. The SEC is capable to monitor strain changes over a large structural surface and undergo large deformations under cracking. Previous tests verified that the SEC can detect and localize fatigue cracks under low-cycle fatigue loading. In this paper, we further investigate the SEC's capability for monitoring high-cycle fatigue cracks, which are commonly seen in steel bridges. The peak-to-peak amplitude (pk-pk amplitude) of the SEC measurement is proposed as an indicator of crack growth. This technique is is robust and insensitive to long-term capacitance drift. To overcome the difficulty of identifying the pk-pk amplitude in time series due to high signal-to-noise ratio, a signal processing method is established. This method converts the measured SEC capacitance and applied load to power spectral densities (PSD) in the frequency domain, such that the pk-pk amplitudes of the measurements can be accurately extracted. Finally, the performance of this method is validated using a fatigue test of a compact steel specimen equipped with a SEC. Results show that the crack growth under high-cycle fatigue loading can be successfully monitored using the proposed signal processing method.

This report describes the design and construction of a tilting platform for sorting household waste, limited to plastic, glass, and metal. The platform utilizes a capacitive sensor to identify if an object is placed on the platform, an inductive sensor to detect metal, and a load cell to differentiate between plastic and glass based on their weight difference. The load cell was found to be inaccurate due to sensitivity to physical changes in the environment and sensor placement, leading to inaccurate weight measurements. Relocating the sensors away from the load cell is recommended to improve accuracy. The platform tilts using to two servomotors, which makes the platform tilt in two degrees of freedom. This solution worked as thought out, except for the universal joint having poor quality, resulting in a wobbly motion. / Denna rapport beskriver designen och konstruktionen av en vippande plattform för sortering av hushållsavfall begränsat till plast, glas och metall. Plattformen använder en kapacitiv sensor för att identifiera om ett föremål placeras på den, en induktiv sensor för att detektera metall och en lastcell för att skilja mellan plast och glas baserat på deras viktskillnad. Lastcellen visade sig vara opålitlig på grund av dess känslighet för fysiska förändringar i miljön och placeringen av sensorerna, vilket ledde till felaktiga viktmätningar. Det rekommenderas att flytta sensorerna bort från lastcellen för att förbättra noggrannheten. Den lutande funktionen drivs av två servomotorer som var funktionell men hade en ostadig rörelse på grund av dåliga universal joints.