<p><p>This project aims in building a new experimental setup for capacitive measurements of a pH-Sensor. PAA-IOA (Poly Acrylic Acid co – Iso Octyl Acrylate) is the dielectric material over the in-plane interdigitated gold electrodes where PAA IOA acts as an H⁺ ion sensing layer. The changes in the capacitance of the sensor when the sensor is dipped into different pH solutions will be quantized accordingly. The dipping setup is built in such a way that the electrodes (containing the polymer layer) can be easily dipped into different pH liquids and to eliminate any contact between the polymer and set-up (e.g. pressure effects on the sensor). From the setup it is visible that the gold electrodes are not subjected to any external force as in the case of the setup used previously. Three phases of experiments have been used in this project to get a clear view on the working principle of the polymer. The effect of pH is only considered in this project, as we already have the evidences for the salt sensitiveness of PAA IOA from the work done in the past. The influence of various pH on polymer is observed as capacitance measurements. Response time is more than 5 minutes for PAA IOA. ∆C decreases with frequency and frequency choice depends on application/electronics. The degree of other ions influence is not clear but they have a minor influence in the resistance.</p></p>

Thesis (M.E.E.)--University of Delaware, 2006. / Principal faculty advisor: Balaji Panchapakesan, Dept. of Electrical and Computer Engineering. Includes bibliographical references.

This project aims in building a new experimental setup for capacitive measurements of a pH-Sensor. PAA-IOA (Poly Acrylic Acid co – Iso Octyl Acrylate) is the dielectric material over the in-plane interdigitated gold electrodes where PAA IOA acts as an H+ ion sensing layer. The changes in the capacitance of the sensor when the sensor is dipped into different pH solutions will be quantized accordingly. The dipping setup is built in such a way that the electrodes (containing the polymer layer) can be easily dipped into different pH liquids and to eliminate any contact between the polymer and set-up (e.g. pressure effects on the sensor). From the setup it is visible that the gold electrodes are not subjected to any external force as in the case of the setup used previously. Three phases of experiments have been used in this project to get a clear view on the working principle of the polymer. The effect of pH is only considered in this project, as we already have the evidences for the salt sensitiveness of PAA IOA from the work done in the past. The influence of various pH on polymer is observed as capacitance measurements. Response time is more than 5 minutes for PAA IOA. ∆C decreases with frequency and frequency choice depends on application/electronics. The degree of other ions influence is not clear but they have a minor influence in the resistance.

This project is about to create a multi sensor modular platform for robots. That means a platform created with several sensors, actuators and chips that had to be useful for future robot practice or projects. As this project is a platform for future thesis, is required to use standard programming language, creating the control of the sensors so that it could be easily used by other students in the future, although they did not know the inner working of programs in particular. Although this platform can be used for multiple applications, this thesis give special attention on a future project that the mainly purpose is create a robot capable of follow scents, or what is the same, different concentrations of gas. Thus, although the programs that we had to create could be used for various purposes, are specially done thinking of the future use for the creation of this robot tracker of smells. So the main task of this project is to investigate and see how each of the sensors and actuators of our robot works and, in the other hand, learn to program a chip set not only to make it able to receive information from these sensors and send information to the actuators, but create some laws to control our multi sensor modular platform for robots to perform tasks from the acquired information. Basically our robot is able to follow the direction that we want, with a close control loop in the direction using the information acquired from a three axis accelerometer, which allows too knowing the acceleration and consequently velocity and position of our robot. Also the robot is equipped with ultra sound sensors allowing detecting and avoiding obstacles. The smell sensor is implemented for the next versions of this robot.

Unfortunately, people die and get injured due to accidents in the traffic. Furthermore, statistics of road accidents is limited and mostly composed of serious accidents, making it difficult to draw conclusions about how to improve the safety in the traffic. Thus, there is an interest in obtaining information about critical events in the traffic, i.e. potential accident situations, since they occur much more frequently. One way of detecting critical events is to use sensors, such as accelerometers and gyroscopes. As the usage of cellphones with built-in sensors increases, it would be interesting to examine whether these sensors are good enough to detect critical events. This is where the focus of this thesis lies. An application that collects data from the cellphone’s built-in accelerometer, gyroscope and GPS was developed and tested. The data was then analysed and compared to data from accurate sensors, represented by a VBOX coupled to an IMU. The conclusions made in this thesis are that the sensors in the cellphone perform almost equivalent results compared to the VBOX. It is possible to use data from the sensors in orderto detect critical events.

Monitoring and controlling of insects are of great scientific and engineering interests based on the potential impacts on environments, search and rescue operations, and robotics design. This research focuses on studying insects’ locomotive behavior by employing noninvasive piezoelectric sensors and presenting a conceptual method of locomotion control. To do so, polyvinylidene fluoride thin sheets are used as bending sensors at the joints of a cockroach’s legs. Approaches include development of polymeric sensors; laboratory in vitro testing of sensors and cockroaches; and methodology to control them. This research successfully built an experimental foundation for sensor and roach testing and developed a methodology for roach locomotion control. This research links engineering and entomology potentially having impacts in the mentioned arenas. Testing showed that piezoelectric films, such as polyvinylidene fluoride (PVDF), can serve as motion sensors for the legs, providing frequency and range of motion of each of the roach’s legs. The film is thin enough to provide as little resistance to motion to prevent altering the roach’s natural walking patterns. Testing also showed that using the insect’s instinct to physically touch an unknown object can be used as a directional control method. By using this natural response, a device can be fit on the roach capable of guiding the roach in any direction desired. This thesis is organized to present a brief introduction on the history and need for biomimetic robots. This section is followed by the research objectives and an introduction to polyvinylidene fluoride and the piezoelectric properties that allow it to become a sensor. A brief description of the roach anatomy and physiology is presented that will provide baseline of information needed to proceed with the project. We finish with an explanation of the testing of sensors on the roach and a novel method to control the roach walking orientation.

A new equivalent circuit model for IGBT is presented. It takes into account both electron and hole conduction in sensors and is incorporated with SPICE3 for the simulation of three types of current sensors, namely active, bipolar, and MOS sensors. It adopts a multi-MOS model to include the doping variation in the MOS body. The results agree well with the current sensing measurements within an average error of 4.4%.

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Most of today's aircraft used for the commercial transport of passengers or military aircraft still rely on simple technology such as cables, connectors and sensors to provide power, avionics data, control system, aircraft instrumentation etc. throughout the vehicle's life-cycle for flight monitoring and fault diagnosis. Despite a marked improvement in the quality and reliability of these components, they continue to be the main cause of failures due to corrosion, misuse, improper installation, etc, using-up endless man-hours to troubleshoot, repair and upgrade them. Wireless monitoring by telemetry of some of the critical systems has been in use for some time as a point to point data link designed to provide vital information, potentially improving the safety and efficiency of any flight. Aircraft manufacturers are now looking at the use of wireless networks to replace current data buses used for the transfer of data between avionics systems and their sensors as well as for the control of some of the surface actuators. Wireless networks used in this way could reduce the amount of cabling and its associated weight as well as simplify the re-routing of connections making upgradation less expensive and quicker, again a benefit to airlines. Despite many benefits there is a potentially serious security issue by means of an introduction of a backdoor into the system, meaning that before aircrafts become network-enabled, all the security issues must be identified in full and dealt with.

Low cost, low power wireless sensors (motes) promise to revolutionize environmental data collection, but are they currently refined enough for widespread use by hydrologists? Their viability as a replacement for traditional data collection techniques was investigated in a 7 ha forested watershed in south-western British Columbia. The watershed included 41 instrument clusters measuring air and soil temperature, humidity, throughfall, soil moisture content, overland flow and groundwater head. The foundation of each cluster was a data box containing a MDA300 data acquisition board and a MICA2 processor board from Crossbow Technologies, Inc.™ that allowed for short range wireless data collection. The 41 motes each recorded data every 15 minutes from July, 2006, to April, 2007. In addition to reporting on the reliability of the motes and sensors during the 10 months deployment, the high spatial and temporal resolution data collected by this study gave the opportunity for many analyses of catchment processes. As soil moisture and throughfall are two influential processes in the exchange of water between the earth and the atmosphere, these were the focus of the data analysis. The first analysis was a resampling experiment on seven different events selected from the full data set. Comparing 100 different subsamples each of 5, 10 and 20 points for throughfall and soil moisture showed if increasing the sample size eventually produced diminishing returns in the ability to reproduce the true catchment mean. With significant differences in prediction ability for both soil moisture and throughfall at times of differing hydrologic activity, this analysis provides further support for the theories of changing moisture states of soil moisture and threshold values for throughfall. The second analysis described how the organization of soil moisture and throughfall changed during a range of weather conditions and timescales. Spatial representation of normalized values and Pearson correlation coefficients showed that there were distinct differences between wet and dry periods for soil moisture and between long and short analysis periods for throughfall.

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