Capacitive Sensor Interface Using an Inverter-Based Period Modulator

This thesis discusses the basic principles, circuit implementation and measurements of an inverter-based capacitive-sensor interface based on period modulation. The interface employs an inverter-based OTA and comparator to increase the current efficiency. Moreover, it applies new circuit techniques to reduce the die size and to reduce noise. A...

A Capacitive Implementation of an Online Sensor Grid for Measuring Grease Deposition in Extraction Channels

An extraction channel cleaning company wanted a grease thickness sensor to be developed that would send the data via the internet so that information on the thickness could be accessed remotely. This system consists of two parts: the sensor part and a communications part. This report is on the sensor part, which uses a change in capacitance of...

An atto-Farad resolution closed loop impedance measurement bridge for capacitive sensors

This thesis discusses the theory, circuit design, software design and measurements of an atto-Farad resolution closed-loop impedance measurement bridge circuit for capacitive sensors implemented using commercial off the shelf components.<br/>A lock-in amplifier (LIA) method is used here. The capacitive sensor embedded in an impedance bridge is...

Design and Development of Integrated Displacement Sensors for Engineered Heart Tissue Platforms

Cardiac cells derived from stem cells exhibit cellular contractions when cultured in vitro. They can be integrated with polymeric platforms consisting of micropillars, which act as anchors and pre-load for engineered heart tissue (EHT). The biomechanical response is often characterized using optical microscopy to track the displacement of pillar...

A 3-by-3 400-MHz LC microsensor array for wireless capacitive biosensing

Biosensing has been developed rapidly for a number of biomedical applications, including neural monitoring, protein detection, bacteria detection and blood glucose monitoring. Among the branches of bio-sensing, capacitive sensing is a promising technique and utilized widely, since it is rapid, simple, label free and inexpensive. Compared with...

Sensor Integration in PV Devices: State of the Art and Future Opportunities

The on-field performance and lifespan of PV modules are affected by the interaction of numerous parameters, among which temperature, strain, and humidity. Among these parameters, only temperature is occasionally measured in PV installations, and such monitoring is often external to the module. This limits its use and does not provide accurate...

PASiC Ammonia Sensor Design: On Modelling the PASiC Layer, Electrode Designs and Device Fabrication

Capacitive, interdigital sensors in proximity of a PASiC thin film have been proposed as a cheap, robust alternative to existing ammonia sensing technologies. However, although prototype sensors have been manufactured, investigation into the working principles of this class of ammonia sensors is limited. This work aims to analyse the electrode...

Towards a read-out for capacitive displacement sensor in an engineered heart tissue device

Engineered Heart Tissues (EHTs) are a valuable approach enabled by Organ-on-Chip (OoC) technology to model human cardiac tissue. These small microfluidic devices allow the culture and development of living cardiac cells in 3D structures, to reproduce tissue dynamics and functionality in-vitro, thus fostering the development of new and more...

Design, Production and Characterisation of an LPCVD-Based Poly-Silicon Carbide Pressure Sensor for Extreme Environments

Sensors are extremely valuable to this world. Without sensors, we would not be able to live as we do in this data-driven environment. Therefore, finding new ways to measure the matter around us is a continuous process. In this work, an addition to the new sensors is attempted, using materials that can withstand the most extreme circumstances....

A Capacitive Hair-like MEMS Airflow Sensor for Flapping Wing Micro Air Vehicles

Airspeed information plays a crucial role in the takeoff, flight, and landing processes in animal flyers and aerial vehicles. Among the aerial vehicles, Flapping Wing Micro Air Vehicles (FWMAVs) represent the novel engineering approach of learning and mimicking animal flyers in the past two decades. A few prototypes of various sizes and...