Ultrasonic based easy parking system based on Microcontroller

The prime objective of this research is to avoid collision and reliable vehicle parking system. Ultrasonic sensor plays a vital role in grain level filling in a container because fill level is calculated by measuring the distance information.Parking sensor system use either electromagnetic or ultrasonic sensor which alert the driver about the obstacles in the path while parking. Basically,the sensor detects the nearby objects. It will be help in terms of unplanned parking, also one kind of wasting time and wasting fuel. So,in a short time one could easily find a parking slot with low consuming fuel. Principally,drivers are frustrated while waiting for the parking for a longer time. Therefore,this challenge can be possible through the ultrasonic sensor

The design and intelligent control of an autonomous mobile robot

This thesis presents an investigation into the problems of exploration, map building and collision free navigation for intelligent autonomous mobile robots. The project began with an extensive review of currently available literature in the field of mobile robot research, which included intelligent control techniques and their application. It became clear that there was scope for further development with regard to map building and exploration in new and unstructured environments. Animals have an innate propensity to exhibit such abilities, and so the analogous use of artificial neural networks instead of actual neural systems was examined for use as a method of robot mapping. A simulated behaviour based mobile robot was used in conjunction with a growing cell structure neural network to map out new environments. When using the direct application of this algorithm, topological irregularities were observed to be the direct result of correlations within the input data stream. A modification to this basic system was shown to correct the problem, but further developments would be required to produce a generic solution. The mapping algorithms gained through this approach, although more similar to biological systems, are computationally inefficient in comparison to the methods which were subsequently developed. A novel mapping method was proposed based on the robot creating new location vectors, or nodes, when it exceeded a distance threshold from its mapped area. Network parameters were developed to monitor the state of growth of the network and aid the robot search process. In simulation, the combination of the novel mapping and search process were shown to be able to construct maps which could be subsequently used for collision free navigation. To develop greater insights into the control problem and to validate the simulation work the control structures were ported to a prototype mobile robot. The mobile robot was of circular construction, with a synchro-drive wheel configuration, and was equipped with eight ultrasonic distance sensors and an odometric positioning system. It was self-sufficient, incorporating all its power and computational resources. The experiments observed the effects of odometric drift and demonstrated methods of re-correction which were shown to be effective. Both the novel mapping method, and a new algorithm based on an exhaustive mesh search, were shown to be able to explore different environments and subsequently achieve collision free navigation. This was shown in all cases by monitoring the estimates in the positional error which remained within fixed bounds

Multiplexed, High Density Electrophysiology with Nanofabricated Neural Probes

Extracellular electrode arrays can reveal the neuronal network correlates of behavior with single-cell, single-spike, and sub-millisecond resolution. However, implantable electrodes are inherently invasive, and efforts to scale up the number and density of recording sites must compromise on device size in order to connect the electrodes. Here, we report on silicon-based neural probes employing nanofabricated, high-density electrical leads. Furthermore, we address the challenge of reading out multichannel data with an application-specific integrated circuit (ASIC) performing signal amplification, band-pass filtering, and multiplexing functions. We demonstrate high spatial resolution extracellular measurements with a fully integrated, low noise 64-channel system weighing just 330 mg. The on-chip multiplexers make possible recordings with substantially fewer external wires than the number of input channels. By combining nanofabricated probes with ASICs we have implemented a system for performing large-scale, high-density electrophysiology in small, freely behaving animals that is both minimally invasive and highly scalable

The GALATEA test facility and a first study of alpha-induced surface events in a Germanium detector

Germanium detectors are a choice technology in fundamental research. They are suitable for the search for rare events due to their high sensitivity and excellent energy resolution. As an example, the GERDA (GERmanium Detector Array) experiment searching for neutrinoless double beta decay is described. The observation of this decay would resolve the fundamental question whether the neutrino is its own antiparticle. Especially adapted detector technologies and low background rates needed to detect very rare events such as neutrinoless double beta decays are discussed. The identification of backgrounds originating from the interaction of radiation, especially alpha-particles, is a focus of this thesis. Low background experiments face problems from alpha-particles due to unavoidable surface contaminations of the germanium detectors. The segmentation of detectors is used to obtain information about the special characteristics of selected events. The high precision test stand GALATEA was especially designed for surface scans of germanium detectors. As part of this work, GALATEA was completed and commissioned. The final commissioning required major upgrades of the original design which are described in detail. Collimator studies with two commercial germanium detectors are presented. Different collimation levels for a beta-source were investigated and crystal axis effects were examined. The first scan with an alpha-source of the passivated end-plate of a special 19-fold segmented prototype detector mounted in GALATEA is described. The alpha-induced surface events were studied and characterized. Crosstalk and mirror pulses seen in the segments of the germanium detector were analyzed. The detector studies presented in this thesis will help to further improve the design of germanium detectors for low background experiments.Germaniumdetektoren eignen sich für die Suche nach sehr seltenen Ereignissen, da sie aufgrund ihrer hohen Sensitivität und hervorragenden Energieauflösung geringe Mengen von Radioaktivität nachweisen können. Germaniumdetektoren finden daher zum Beispiel Anwendung beim GERDA (GERmanium Detector Array) Experiment, welches sich mit der Suche nach dem neutrinolosen doppelten Betazerfall beschäftigt. Die Beobachtung dieses Zerfalls würde die fundamentale Frage beantworten, ob das Neutrino sein eigenes Antiteilchen ist. Die experimentelle Voraussetzung zum Nachweis von sehr seltenen Ereignissen wie dem neutrinolosen doppelten Betazerfall sind niedrige Untergrundraten und speziell angepasste Detektortechnologien. Das GERDA Experiment sowie Methoden zur Untergrundminimierung werden vorgestellt. Unvermeidbare Oberflächenkontaminationen von Germaniumdetektoren erzeugen einen zusätzlichen intrinsischen Untergrund. Im Besonderen werden Oberflächenereignisse, die durch die Wechselwirkung von alpha-Teilchen, entstehen im Rahmen dieser Arbeit diskutiert. Eine spezielle Segmentierung der Detektoren liefert zusätzliche Informationen zur Unterscheidung von Signal und Untergrundereignissen. Ein eigens zur Untersuchung von Oberflächenereignissen entwickelter Hochpräzisionsteststand, GALATEA, wurde im Rahmen dieser Arbeit vollständig in Betrieb genommen. Die Inbetriebnahme der Apparatur erforderte umfangreiche Umbaumaßnahmen und die Implementierung zusätzlicher Komponenten. In der Vorbereitung wurden auch Kollimatorstudien an zwei kommerziellen Germaniumdetektoren durchgeführt. Das Kollimationsverhalten sowie Kristallachseneffekte wurden untersucht. Die Oberfläche eines speziell 19-fach segmentierten Prototyp-Detektors wurde erstmalig in GALATEA mit einer alpha-Quelle abgetastet. Oberflächennahe Ereignisse wurden untersucht und charakterisiert. Die hier vorgestellten Detektorstudien dienen der Untersuchung und Charakterisierung von Germaniumdetektoren. Die daraus gewonnenen Resultate können nützlich für die Identifizierung von Untergrundereignissen im GERDA Experiment sein oder generell Anwendung in Experimenten finden, die Germaniumdetektoren verwenden

Impact detection techniques using fibre-optic sensors for aerospace & defence

Impact detection techniques are developed for application in the aerospace and defence industries. Optical fibre sensors hold great promise for structural health monitoring systems and methods of interrogating fibre Bragg gratings (FBG) are investigated given the need for dynamic strain capture and multiplexed sensors. An arrayed waveguide grating based interrogator is developed. The relationships between key performance indicators, such as strain range and linearity of response, and parameters such as the FBG length and spectral width are determined. It was found that the inclusion of a semiconductor optical amplifier could increase the signal-to-noise ratio by ~300% as the system moves to its least sensitive. An alternative interrogator is investigated utilising two wave mixing in erbium-doped fibre in order to create an adaptive system insensitive to quasistatic strain and temperature drifts. Dynamic strain sensing was demonstrated at 200 Hz which remained functional while undergoing a temperature shift of 8.5 °C. In addition, software techniques are investigated for locating impact events on a curved composite structure using both time-of-flight triangulation and neural networks. A feature characteristic of composite damage creation is identified in dynamic signals captured during impact. An algorithm is developed which successfully distinguishes between signals characteristic of a non-damaging impact with those from a damaging impact with a classification accuracy of 93 – 96%. Finally, a demonstrator system is produced to exhibit some of the techniques developed in this thesis

The development of localisation capabilities and control for a low-cost robot

Includes bibliographical references (leaves 58-61).A fully autonomous robot which can perform dangerous or mundane tasks is the ideal outcome of robotic research. A variety of commercially available household robots such as robotic vacuum cleaners exist but are limited in their navigation ability. In general, they tend to use random search patterns to navigate a room and overestimate the time required to clean the room in order to ensure covering the entire area. The ability to map the environment and then use this map to navigate is an essential step towards total autonomy, and would greatly improve the efficiency of these household robots. Autonomous mapping is a complex problem as the robot must use sensor readings to generate a map while at the same time using that map to locate itself and navigate. One component of the mapping task is localisation. This is the process of determining position and orientation from sensor data given a known map. This was the focus of this work as a first-step towards an autonomous mapping robot. This project continued the work of an undergraduate thesis in which a robot vacuum base was built. Using this base, the sensing and control systems were developed. The selection of a suitable controller was an important aspect of the development. It had to be suitable not only for this task but allow for expansion of the control capabilities should the project be extended. The Gumstix/Roboaudiostix embedded system was chosen and performed successfully. Its extremely small size and low power requirements are a feature of the system

The GALATEA test facility and a first study of alpha-induced surface events in a Germanium detector

Germanium detectors are a choice technology in fundamental research. They are suitable for the search for rare events due to their high sensitivity and excellent energy resolution. As an example, the GERDA (GERmanium Detector Array) experiment searching for neutrinoless double beta decay is described. The observation of this decay would resolve the fundamental question whether the neutrino is its own antiparticle. Especially adapted detector technologies and low background rates needed to detect very rare events such as neutrinoless double beta decays are discussed. The identification of backgrounds originating from the interaction of radiation, especially alpha-particles, is a focus of this thesis. Low background experiments face problems from alpha-particles due to unavoidable surface contaminations of the germanium detectors. The segmentation of detectors is used to obtain information about the special characteristics of selected events. The high precision test stand GALATEA was especially designed for surface scans of germanium detectors. As part of this work, GALATEA was completed and commissioned. The final commissioning required major upgrades of the original design which are described in detail. Collimator studies with two commercial germanium detectors are presented. Different collimation levels for a beta-source were investigated and crystal axis effects were examined. The first scan with an alpha-source of the passivated end-plate of a special 19-fold segmented prototype detector mounted in GALATEA is described. The alpha-induced surface events were studied and characterized. Crosstalk and mirror pulses seen in the segments of the germanium detector were analyzed. The detector studies presented in this thesis will help to further improve the design of germanium detectors for low background experiments.Germaniumdetektoren eignen sich für die Suche nach sehr seltenen Ereignissen, da sie aufgrund ihrer hohen Sensitivität und hervorragenden Energieauflösung geringe Mengen von Radioaktivität nachweisen können. Germaniumdetektoren finden daher zum Beispiel Anwendung beim GERDA (GERmanium Detector Array) Experiment, welches sich mit der Suche nach dem neutrinolosen doppelten Betazerfall beschäftigt. Die Beobachtung dieses Zerfalls würde die fundamentale Frage beantworten, ob das Neutrino sein eigenes Antiteilchen ist. Die experimentelle Voraussetzung zum Nachweis von sehr seltenen Ereignissen wie dem neutrinolosen doppelten Betazerfall sind niedrige Untergrundraten und speziell angepasste Detektortechnologien. Das GERDA Experiment sowie Methoden zur Untergrundminimierung werden vorgestellt. Unvermeidbare Oberflächenkontaminationen von Germaniumdetektoren erzeugen einen zusätzlichen intrinsischen Untergrund. Im Besonderen werden Oberflächenereignisse, die durch die Wechselwirkung von alpha-Teilchen, entstehen im Rahmen dieser Arbeit diskutiert. Eine spezielle Segmentierung der Detektoren liefert zusätzliche Informationen zur Unterscheidung von Signal und Untergrundereignissen. Ein eigens zur Untersuchung von Oberflächenereignissen entwickelter Hochpräzisionsteststand, GALATEA, wurde im Rahmen dieser Arbeit vollständig in Betrieb genommen. Die Inbetriebnahme der Apparatur erforderte umfangreiche Umbaumaßnahmen und die Implementierung zusätzlicher Komponenten. In der Vorbereitung wurden auch Kollimatorstudien an zwei kommerziellen Germaniumdetektoren durchgeführt. Das Kollimationsverhalten sowie Kristallachseneffekte wurden untersucht. Die Oberfläche eines speziell 19-fach segmentierten Prototyp-Detektors wurde erstmalig in GALATEA mit einer alpha-Quelle abgetastet. Oberflächennahe Ereignisse wurden untersucht und charakterisiert. Die hier vorgestellten Detektorstudien dienen der Untersuchung und Charakterisierung von Germaniumdetektoren. Die daraus gewonnenen Resultate können nützlich für die Identifizierung von Untergrundereignissen im GERDA Experiment sein oder generell Anwendung in Experimenten finden, die Germaniumdetektoren verwenden

Prototipe Peringatan Dini Banjir dengan Menerapkan Teknologi Internet of Thing

Salah satu dampak nyata dari perubahan iklim adalah banjir yang telah terjadi lebih sering di banyak wilayah padat penduduk dan menyebabkan dampak pada kehidupan manusia dan mata pencaharian. Tujuan penelitian ini adalah membangun algoritma untuk memudahkan seseorang atau pengguna dapat mengetahui kondisi dan mendapat peringatan tentang ketinggian permukaan air terhadap permukaan jalan raya. Pengguna dapat memonitor ketinggian air dengan menggunakan smartphone apabila ketinggian permukaan air kanal dibawah permukaan jalan, dan pengguna akan mendapat peringatan apabila tiba-tiba permukaan air meningkat melebihi permukaan jalan secara real time. Untuk medapatkan ketinggian permukaan air kanal, dengan cara memanfaatkan rambatan gelombang suara ultrasonit yang dipantulkan pada obyek. Dengan diketahuinya jarak obyek, maka dapat dilakukan komputasi untuk mengetaui ketinggian permukaan air kanal. Nilai ketinggian permukaan air kanal dikrim melalui jaringan internet menuju Internet of Thing (IoT) cloud server  yang dapat di monitor oleh pengguna. Sedangkan nilai ketinggian permukaan air kanal yang tidak normal akan menjadi keputusan untuk memberi interupsi peringatan kepada pengguna, apabila pengguna sedang tidak dalam keadaan sedang memantau. Hasil percobaan pada prototipe ini mampu memberikan representasi variabel ketinggian permukaan air dalam bentuk grafis dan nilai numerik, serta mampu memberi peringatan pada pengguna melalui smartphone. Sistem peringatan dini banjir mampu merepresentasikan data dalam bentuk level vertikal dan data numerik dengan tinggkat ketinggian air paling rendah adalah -150 cm dan paling tinggi 130 cm, dengan representasi nilai 0 cm apabila tingkat ketinggian  permukaan air sejajar dengan permukaan badan jalan. Interupsi peringatan muncul apabila nilai tingkat ketinggian air lebih dari 0 cm

Review of Ultrasonic Ranging Methods and Their Current Challenges

Ultrasonic ranging has been widely used in automobiles, unmanned aerial vehicles (UAVs), robots and other fields. With the appearance of micromachined ultrasonic transducers (MUTs), the application of ultrasonic ranging technology presents a more extensive trend. This review focuses on ultrasonic ranging technology and its development history and future trend. Going through the state-of-the-art ultrasonic ranging methods, this paper covers the principles of each method, the signal processing methodologies, the overall system performance as well as key ultrasonic transducer parameters. Moreover, the error sources and compensation methods of ultrasonic ranging systems are discussed. This review aims to give an overview of the ultrasonic ranging technology including its current development and challenges

A novel heterodyne interferometer for scanning optical microscopy

A phase sensitive scanning optical microscope is described which can measure surface height changes of about 1 Å. The system is based on a heterodyne version of the Michelson interferometer, and has been designed to reject phase noise caused by vibration in the optics and the sample. A specially constructed objective lens is used to direct two laser beams onto the object surface. The first beam forms a tightly focused spot to probe the sample structure and the second remains collimated, acting as a large area on sample reference beam. In the simplest implementation, the objective may be fabricated by drilling a hole in a lens singlet. The configuration allows the relative areas illuminated by the two beams to be varied both arbitrarily and independently, thus guaranteeing an accurate absolute phase measurement. This is an important advantage over existing techniques, in which the range of suitable samples is restricted by the limited size of the on sample reference beam. The two beams reflected from the sample are interfered with a third frequency shifted beam, so forming two heterodyne Michelson interferometers in parallel. The light from each interferometer is detected separately, resulting in two AC signals. The phase of these signals are then compared to provide the object surface phase structure. Path length fluctuations due to microphonics are common to both interferometers and are cancelled by this comparison. Results from a bench top version of the system are presented which demonstrate the principle of the technique and a detailed study is made of the factors limiting the sensitivity of the phase measurement. The conclusions of this study have been applied to the design of a prototype microscope and this has been used to record micrographs of a number of representative samples. In addition the particular imaging characteristics of the system are discussed using a combination of geometrical optics and a transfer function approach