Aus einkristallinem Silizium gefertigte Mikroscanner werden zunehmend in Anwendungen zur Bildprojektion, Entfernungssensorik, Spektroskopie und gezielten Strahlführung von Lasern eingesetzt, denn sie ermöglichen die Miniaturisierung und Massenfertigung optischer Systeme. Durch die statische Strahlpositionierung und zum linearen Rasterscannen in einem breiten Frequenzbereich von Null bis mehrere hundert Hertz eröffnen sogenannte quasi-statische Mikroscanner im Vergleich zu bisherigen resonant schwingenden Mikroscannern ein deutlich breiteres und flexibleres Anwendungsspektrum. Jedoch wird die Bewegung aufgrund der extrem geringen Dämpfung des Systems mit Eigenschwingungen überlagert. Daher ist die Steuerung und Regelung eine notwendige Voraussetzung für die hochdynamische und präzise Strahlführung mit quasi-statischen Mikroscannern. In dieser Arbeit werden verschiedene Steuerungs- und Regelungskonzepte für quasi-statische Mikroscanner mit elektrostatischem Kammantrieb entworfen und auf einem Echtzeitsystem mit optischer Rückführung experimentell verifiziert. Das nichtlineare mechatronische Modell wird vollständig parametrisiert und geeignete Trajektorien mit Ruckbegrenzung werden hergeleitet. Schließlich werden die Regelung des Mikroscanners mit einem Mikrocontroller durch die im Chip integrierte piezoresistive Positi-nssensorik validiert und ein 2D-Rasterscan realisiert. Als Ergebnis werden Folgerungen für den Systementwurf von quasi-statischen Mikroscannern abgeleitet.:Kurzfassung Abstract Inhaltsverzeichnis Abbildungs- und Tabellenverzeichnis Abkürzungs- und Symbolverzeichnis 1 Einleitung 1.1 Anwendungsgebiete 1.2 Antriebsprinzipien für Mikroscanner 1.3 Quasi-statische Mikroscanner des Fraunhofer IPMS 1.4 Mechatronische Modellbildung 1.4.1 Elektrostatischer Elementarwandler 1.4.2 Mechanische Beschaltung 1.4.3 Impedanzrückkopplung 2 Stand der Technik und eigene Beiträge 2.1 Steuerungs- und regelungstechnische Aspekte 2.1.1 Steuerung 2.1.2 Regelung 2.2 Präzisierung der Aufgabenstellung 2.3 Problemstellungen und eigene Beiträge 3 Modellbildung 3.1 Physikalische Modellbildung 3.1.1 Elektrisches Teilsystem 3.1.2 Mechanisches Teilsystem 3.1.3 Mechatronischer Wandler 3.2 Regelungstechnische Modellbildung 3.2.1 Kleinsignalmodell 3.2.2 Zustandsraummodell und Flachheit 3.3 Experimentelle Modellbildung 3.3.1 Bestimmung der Federsteifigkeit und der Dämpfung 3.3.2 Bestimmung der Kapazitätskennlinien 3.4 Schlussfolgerungen 4 Trajektorienentwurf 4.1 Anforderungen 4.1.1 FOURIER-Zerlegung von Dreieck- und Sägezahnfunktion 4.1.2 Überlagerung mit der Streckendynamik 4.2 Ruckbegrenzung 4.2.1 Stufentrajektorie 4.2.2 Dreieck- und Sägezahntrajektorien 4.3 Entwurf mit Regelreserve 4.3.1 Aktuationsbereich 4.3.2 Regelreserve 4.4 Schlussfolgerungen 5 Steuerungs- und Regelungsentwurf 5.1 Steuerung 5.1.1 Statische Steuerung 5.1.2 Vorfilter 5.1.3 Flachheitsbasierte Vorsteuerung 5.1.4 Simulationsergebnisse 5.1.5 Fazit 5.2 Vorauswahl geeigneter Regelungsalgorithmen 5.3 Lineare Regelung 5.3.1 Robuster PID-Regler 5.3.2 Gain-Scheduling-Regler 5.4 Nichtlineare Regelung 5.4.1 Flachheitsbasierte Regelung 5.4.2 Gleitzustandsregelung 5.4.3 Beobachterentwurf 5.4.4 Flachheitsbasierte Vorsteuerung mit Ausgangsstabilisierung 5.4.5 Fazit 5.5 Repetitive Regelung 5.5.1 Dimensionierung des Stabilitätsfilters 5.5.2 Dimensionierung des Lernfilters 5.5.3 Entwurf im linearen und nichtlinearen Regelkreis 5.6 Simulative Verifikation der Regelungsalgorithmen 5.6.1 Simulationsmodell 5.6.2 Simulationsergebnisse 5.6.3 Reglerparametrierung 5.6.4 Regelfrequenzvariation 5.6.5 Variation der Modellparameter 5.6.6 Einfluss von Messrauschen 5.7 Schlussfolgerungen 6 Experimentelle Systemverifikation und Diskussion 6.1 Messaufbau mit Echtzeitsystem 6.1.1 Messaufbau 6.1.2 Echtzeitsystem 6.1.3 Auswertung des optischen Positionsdetektors 6.2 Experimentelle Ergebnisse mit Echtzeitsystem 6.2.1 Fehlerdefinition 6.2.2 Modellverifikation 6.2.3 Ergebnisse der Steuerungsverfahren 6.2.4 Ergebnisse der Regelungsverfahren 6.3 Regelung mit Mikrocontroller 6.3.1 Mikrocontroller und Treiberelektronik 6.3.2 Integrierte piezoresistive Positionssensorik 6.3.3 Regelungsergebnisse mit Mikrocontroller 6.4 Zusammenfassende Diskussion der Ergebnisse 7 Folgerungen für den Systementwurf 7.1 Entwurfsraum 7.1.1 Dynamische Deformation 7.1.2 Stabilitätsspannung 7.1.3 Trajektorienentwurfsraum 7.2 Einsatz der Steuerung und Regelung 7.3 Varianten der Kammanordnung 8 Zusammenfassung 8.1 Erreichte Ziele 8.2 Ausblick 8.3 Abschlussfazit Literaturverzeichnis Publikationen Anhang A Modellbildung und Simulation A.1 Elemente der strukturierten Analyse A.2 Grundlagen der Elektrostatik A.3 Ausführlicher Lagrange-Formalismus A.3.1 Q-Koordinaten A.3.2 PSI-Koordinaten A.4 Kapazitätskennlinien A.5 Impedanzrückkopplung A.6 Mikroscannerparameter A.7 Regelparameter der Simulation A.8 Stabilitätsnachweis der flachheitsbasierter Vorsteuerung mit Ausgangsstabilisierung Anhang B Experimentelle Verifikation B.1 Regelparameter der Messung B.2 Spannungs- und Winkelbeschleunigungsverläufe B.3 Ergebnisse der repetitiven Regelung mit Sägezahntrajektorie B.4 Impedanzmessung der Kammkapazitäten B.5 Geräteliste Thesen / Monocrystalline silicon microscanners are increasingly used in applications for image projection, distance sensors, spectroscopy and laser beam control, because they allow the miniaturization and mass production of optical systems. With static beam positioning and linear raster scanning abilities in a wide range of zero to several hundred hertz the so-called quasi-static microscanners offer a much broader and more flexible range of applications compared to common resonantly oscillating microscanners. However, the movement is superimposed with natural oscillations due to the extremely low system damping. Therefore, an open-loop and closed-loop control is necessary for highly dynamic and accurate beam control with quasi-static microscanners. In this thesis different concepts for open-loop and closed-loop control of quasi-static microscanners with electrostatic comb drives are designed and verified experimentally on a real-time system with optical feedback. The nonlinear mechatronic model becomes completely parameterized and suitable trajectories with jerk limitation are derived. The control of the microscanner on a microcontroller with feedback by the on-chip inte-rated piezoresistive position sensors is validated realizing a 2D raster scan. As a result, conclusions for the system design are derived for quasi-static microscanners.:Kurzfassung Abstract Inhaltsverzeichnis Abbildungs- und Tabellenverzeichnis Abkürzungs- und Symbolverzeichnis 1 Einleitung 1.1 Anwendungsgebiete 1.2 Antriebsprinzipien für Mikroscanner 1.3 Quasi-statische Mikroscanner des Fraunhofer IPMS 1.4 Mechatronische Modellbildung 1.4.1 Elektrostatischer Elementarwandler 1.4.2 Mechanische Beschaltung 1.4.3 Impedanzrückkopplung 2 Stand der Technik und eigene Beiträge 2.1 Steuerungs- und regelungstechnische Aspekte 2.1.1 Steuerung 2.1.2 Regelung 2.2 Präzisierung der Aufgabenstellung 2.3 Problemstellungen und eigene Beiträge 3 Modellbildung 3.1 Physikalische Modellbildung 3.1.1 Elektrisches Teilsystem 3.1.2 Mechanisches Teilsystem 3.1.3 Mechatronischer Wandler 3.2 Regelungstechnische Modellbildung 3.2.1 Kleinsignalmodell 3.2.2 Zustandsraummodell und Flachheit 3.3 Experimentelle Modellbildung 3.3.1 Bestimmung der Federsteifigkeit und der Dämpfung 3.3.2 Bestimmung der Kapazitätskennlinien 3.4 Schlussfolgerungen 4 Trajektorienentwurf 4.1 Anforderungen 4.1.1 FOURIER-Zerlegung von Dreieck- und Sägezahnfunktion 4.1.2 Überlagerung mit der Streckendynamik 4.2 Ruckbegrenzung 4.2.1 Stufentrajektorie 4.2.2 Dreieck- und Sägezahntrajektorien 4.3 Entwurf mit Regelreserve 4.3.1 Aktuationsbereich 4.3.2 Regelreserve 4.4 Schlussfolgerungen 5 Steuerungs- und Regelungsentwurf 5.1 Steuerung 5.1.1 Statische Steuerung 5.1.2 Vorfilter 5.1.3 Flachheitsbasierte Vorsteuerung 5.1.4 Simulationsergebnisse 5.1.5 Fazit 5.2 Vorauswahl geeigneter Regelungsalgorithmen 5.3 Lineare Regelung 5.3.1 Robuster PID-Regler 5.3.2 Gain-Scheduling-Regler 5.4 Nichtlineare Regelung 5.4.1 Flachheitsbasierte Regelung 5.4.2 Gleitzustandsregelung 5.4.3 Beobachterentwurf 5.4.4 Flachheitsbasierte Vorsteuerung mit Ausgangsstabilisierung 5.4.5 Fazit 5.5 Repetitive Regelung 5.5.1 Dimensionierung des Stabilitätsfilters 5.5.2 Dimensionierung des Lernfilters 5.5.3 Entwurf im linearen und nichtlinearen Regelkreis 5.6 Simulative Verifikation der Regelungsalgorithmen 5.6.1 Simulationsmodell 5.6.2 Simulationsergebnisse 5.6.3 Reglerparametrierung 5.6.4 Regelfrequenzvariation 5.6.5 Variation der Modellparameter 5.6.6 Einfluss von Messrauschen 5.7 Schlussfolgerungen 6 Experimentelle Systemverifikation und Diskussion 6.1 Messaufbau mit Echtzeitsystem 6.1.1 Messaufbau 6.1.2 Echtzeitsystem 6.1.3 Auswertung des optischen Positionsdetektors 6.2 Experimentelle Ergebnisse mit Echtzeitsystem 6.2.1 Fehlerdefinition 6.2.2 Modellverifikation 6.2.3 Ergebnisse der Steuerungsverfahren 6.2.4 Ergebnisse der Regelungsverfahren 6.3 Regelung mit Mikrocontroller 6.3.1 Mikrocontroller und Treiberelektronik 6.3.2 Integrierte piezoresistive Positionssensorik 6.3.3 Regelungsergebnisse mit Mikrocontroller 6.4 Zusammenfassende Diskussion der Ergebnisse 7 Folgerungen für den Systementwurf 7.1 Entwurfsraum 7.1.1 Dynamische Deformation 7.1.2 Stabilitätsspannung 7.1.3 Trajektorienentwurfsraum 7.2 Einsatz der Steuerung und Regelung 7.3 Varianten der Kammanordnung 8 Zusammenfassung 8.1 Erreichte Ziele 8.2 Ausblick 8.3 Abschlussfazit Literaturverzeichnis Publikationen Anhang A Modellbildung und Simulation A.1 Elemente der strukturierten Analyse A.2 Grundlagen der Elektrostatik A.3 Ausführlicher Lagrange-Formalismus A.3.1 Q-Koordinaten A.3.2 PSI-Koordinaten A.4 Kapazitätskennlinien A.5 Impedanzrückkopplung A.6 Mikroscannerparameter A.7 Regelparameter der Simulation A.8 Stabilitätsnachweis der flachheitsbasierter Vorsteuerung mit Ausgangsstabilisierung Anhang B Experimentelle Verifikation B.1 Regelparameter der Messung B.2 Spannungs- und Winkelbeschleunigungsverläufe B.3 Ergebnisse der repetitiven Regelung mit Sägezahntrajektorie B.4 Impedanzmessung der Kammkapazitäten B.5 Geräteliste Thesen

No description available.

Overcrowding during indoor events can be risky, in-case of any kind of a hazard such as fire.This solution address this by providing real-time crowd detection solution using Force-SensingResistor (FSR) sensors, referred sensor (IR) and microcontrollers. The solution needs to offer accurate data in real-time to the event managers including number of people and entrancerate to help when and if the event areas will be overcrowded, thereby enhancing event safetyand decision-making. This thesis indicate that the system offers essential real-time data forevent safety with an accuracy of 87.25%. These data will assists event managers in makinginformed decisions to avoid the risks of overcrowding. This thesis evaluates the effectivenessof our system in comparison to other systems, discussing what we’ve learned, suggest possibleimprovements, and talk about whether our system could be useful in real-world indoor events.

No description available.

No description available.

New emission legislation regarding air pollution control, as instructed by the Department of Environmental Affairs (DEA) to Eskom Generation Power Stations, implies a particulate emission limit of 100 mg/Nm3 for all existing power stations by 2015 and 50 mg/Nm3 for all new and existing power stations by the year 2020. Some of Eskom’s power stations which are equipped with Electrostatic Precipitators (ESP’s) were not designed for this stringent legislation. It is also experienced that ESP’s and coal quality in Eskom have deteriorated over time, resulting in the performance of the ESP’s not meeting the legislative requirements. Eskom is in the process of introducing various ESP enhancement projects to improve performance and aligning the operating philosophy to comply with the more stringent particulate emission legislation. An ESP efficiency test was conducted at Lethabo Power Station to determine the current state of the plant and performance. The results of the test were compared with the original design base specifications to determine the relevant deficiencies which contribute to high emissions and poor ESP performance. It was aimed to develop an ESP simulation model and validate the outputs with the test data. This study endeavours to demonstrate the greater impact on ESP performance when the ESP is operated outside the design specification. It is further aimed to demonstrate that a solution to the problem of high emissions is not only contributed by the variables within the ESP itself. This study is a coal to stack evaluation considering the ESP variables and the upstream conditions of the ESP that form part of the entire process. The intention of this study is to demonstrate the importance of operating an ESP at the designed parameters and highlight the significance of proper maintenance. It was learned that before any ESP enhancement technology can be implemented, the ESP and upstream conditions must be in accordance with design specifications. The implementation of an ESP enhancement technology will have no merit or justification on a unit that is being operated outside of its design specifications. The results obtained from the ESP simulation model correlated well with the ESP efficiency test data. The expectation of the model to assist operators and engineers to operate ESP’s according to the designer’s specifications was conceded. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

New emission legislation regarding air pollution control, as instructed by the Department of Environmental Affairs (DEA) to Eskom Generation Power Stations, implies a particulate emission limit of 100 mg/Nm3 for all existing power stations by 2015 and 50 mg/Nm3 for all new and existing power stations by the year 2020. Some of Eskom’s power stations which are equipped with Electrostatic Precipitators (ESP’s) were not designed for this stringent legislation. It is also experienced that ESP’s and coal quality in Eskom have deteriorated over time, resulting in the performance of the ESP’s not meeting the legislative requirements. Eskom is in the process of introducing various ESP enhancement projects to improve performance and aligning the operating philosophy to comply with the more stringent particulate emission legislation. An ESP efficiency test was conducted at Lethabo Power Station to determine the current state of the plant and performance. The results of the test were compared with the original design base specifications to determine the relevant deficiencies which contribute to high emissions and poor ESP performance. It was aimed to develop an ESP simulation model and validate the outputs with the test data. This study endeavours to demonstrate the greater impact on ESP performance when the ESP is operated outside the design specification. It is further aimed to demonstrate that a solution to the problem of high emissions is not only contributed by the variables within the ESP itself. This study is a coal to stack evaluation considering the ESP variables and the upstream conditions of the ESP that form part of the entire process. The intention of this study is to demonstrate the importance of operating an ESP at the designed parameters and highlight the significance of proper maintenance. It was learned that before any ESP enhancement technology can be implemented, the ESP and upstream conditions must be in accordance with design specifications. The implementation of an ESP enhancement technology will have no merit or justification on a unit that is being operated outside of its design specifications. The results obtained from the ESP simulation model correlated well with the ESP efficiency test data. The expectation of the model to assist operators and engineers to operate ESP’s according to the designer’s specifications was conceded. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

Silicon-on-Insulator (SOI) CMOS technology constitutes a good candidate for mixed signal RF CMOS applications. Due to its low junction capacitance and reduced leakage current, SOI provides reduced static and dynamic power consumption of the digital logic combined with increased cut-off frequencies. Moreover, in terms of passive device integration the major benefit of SOI when compared to the conventional bulk is the possibility to use a high resistivity substrate which allows a drastic reduction of substrate losses allowing a high quality factor of the passive devices. Another issue is the harsh environment applications. Electronics capable of operating at high temperatures are required in several industrial applications, including the automobile industry, the aerospace industry, the electrical and nuclear power industries, and the well-logging industry. The capability of SOI circuits to expand the operating temperature range of integrated circuits up to 300°C has been demonstrated. SOI devices and circuits present advantages in this field over bulk counterparts such as the absence of thermally-activated latch up and reduced leakage current. In this context, various topologies of integrated transmission lines and spiral inductors implemented on standard and high substrate resistivities have been analyzed over a large temperature range. The temperature behavior of the SOI transistors is presented. The main figures-of-merit of the SOI MOSFETs are analyzed and the extraction of the extrinsic and intrinsic parameters of the small signal equivalent circuit is performed. Also, an example of RF circuit applications of the SOI technology, based on a fully integrated Low-Noise Amplifier for low-power and narrow-band applications, is investigated and characterized at high temperature. The main figures-of-merit of the designed circuit are extracted and discussed. The good results show that the SOI technology is now emerging as a good candidate for the realization of analog integrated circuits for low-power and high-temperature applications.

Ce travail s’insère dans le cadre de l’expérience NEMO cherchant à mettre en évidence une radioactivité extrêmement rare : la double désintégration bêta sans émission de neutrino et par suite d’obtenir des informations sur la nature Dirac-Majorana et sur la masse du neutrino. La particularité de cette expérience actuellement en fin de prise de données au Laboratoire Souterrain de Modane est l’extrême rareté du signal recherché (T1/2 > 1024 ans, quelques événements par an). Il s’ensuit donc des conditions très contraignantes sur toutes les composantes du bruit de fond, et parmi celles-ci sur les niveaux de radon et de thoron. Après quelques rappels sur les propriétés du radon et du thoron et leur influence sur les données de l’expérience NEMO, ce travail de thèse a porté sur la détection de ces gaz radioactifs par la technique de collection électrostatique des descendants sur la surface d’une diode silicium et la détection des alpha émis. Nous avons montré que les rendements de détection sont fortement influencés par les conditions expérimentales et que le niveau de radon pouvait être contrôlé actuellement au niveau du mBq/m3. Une série des mesures de spectrométrie gamma nous a permis de comprendre l’origine du bruit de fond du détecteur de radon, et ainsi d’envisager dans l’avenir un gain en sensibilité en augmentant le volume de détection et en effectuant une sélection très poussée des matériaux non radioactifs. Par contre, pour le thoron, qui n’avait jamais été étudié jusqu’à présent, les efficacités de détection sont très faibles à cause des périodes courtes mises en jeu. Un monitorage continu du thoron dans le gaz de NEMO est donc exclu, ce qui souligne l’importance pour l’expérience NEMO que le dispositif expérimental puisse contrôler son propre bruit de fond. / This work is part of the NEMO (Neutrino Ettore Majorana Observatory) experiment that is looking for an extremely rare radioactivity: the double beta decay without neutrino emission. Such process could prove the Majorana nature of the neutrino and could give an estimation of its absolute mass. The particularity of this experiment, currently running in the Modane underground laboratory (LSM), is the extreme weak signal (for T1/2 ~ 1024 years, a few events per year). It requires therefore very stringent conditions on all components of the background among which the level of radon and thoron activity. After a reminding of the general properties of radon and thoron as well as their influence on the NEMO data, this thesis focuses on the detection of these radioactive gases using the technique of electrostatic collection. The radon and/or the thoron daughters are collected by an electrostatic field on the surface of a silicon diode, where their characteristic alphas are detected. We have shown that the detection efficiencies are strongly influenced by the experimental conditions and that sensitivity around 1 mBq/m3 can be achieved for the radon in a gas. A series of measures through low background gamma spectrometer allowed us to understand the origin of the radon background, and thus showing that better sensitivity could be obtained by increasing the detection volume and by carrying out a strict selection of non-radioactive materials. For the thoron gas, which had never been studied before, the detection efficiencies have been found very low as a consequence of the short periods involved. Therefore, a continuous monitoring of the level of thoron in the NEMO gas is excluded, which underlines the importance for the NEMO experimental device to be able to control its own background. / Nghiên cứu này nằm trong khuôn khổ thí nghiệm NEMO, hiện đang trong những bước lấy số liệu cuối cùng tại phòng thí nghiệm ngầm Modane, nhằm ghi nhận phân rã bêta kép không kèm theo phát xạ neutrino, để từ đó chứng minh bản chất Majorana của hạt neutrino và cho phép ước lượng khối lượng tuyệt đối của hạt này. Phân rã này, nếu thật sự tồn tại, là loại phân rã cực hiếm (T1/2 > 1024 năm, tương đương với vài tín hiệu ghi nhận được mỗi năm). Vì thế, nó đòi hỏi những điều kiện rất gắt gao đối với mọi thành phần cấu thành nên phông nền bức xạ, trong đó bao gồm hoạt độ của radon và thoron. Sau khi nhắc lại những tính chất cơ bản của radon và thoron, cũng như ảnh hưởng của chúng tới số liệu của NEMO, bản luận văn tập trung vào việc đo hoạt độ của hai khí phóng xạ này bằng cách thu nhận các hạt nhân con của chúng thông qua trường tĩnh điện, tiếp đó ghi nhận các hạt alpha phát ra tại bề mặt một đi-ốt silic. Nghiên cứu này đã chỉ ra rằng hiệu suất đo phụ thuộc vào nhiều điều kiện thực nghiệm, và thiết bị này cho phép chúng tôi kiểm soát khí radon ở mức mBq/m3. Một lọat các phép đo với phổ kế gamma đã giúp chúng tôi hiểu được căn nguyên phông nền bức xạ của thiết bị, và từ đó dự kiến có thể cải thiện độ nhạy của thiết bị bằng cách tăng thể tích đo và chọn lọc các loại vật liệu có độ phóng xạ thấp. Tuy nhiên, với khí thoron, vốn vẫn chưa được nghiên cứu kỹ cho tới hiện nay, hiệu suất đo được là rất nhỏ do chu kỳ bán rã quá ngắn của các hạt nhân liên quan. Vì vậy, việc theo dõi thoron trong khí ga của NEMO đã bị loại trừ, đồng nghĩa với việc khẳng định tầm quan trọng của việc kiểm soát phông nền bức xạ thoron của chính thiết bị ghi nhận bêta kép trong thí nghiệm NEMO.

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