Retrospective Cost Adaptive Control of Generic Transport Model Under Uncertainty and Failure

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143070/1/1.I010454.pd

Trim-Commanded Adaptive Control for Waypoint-Defined Trajectory Following

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106500/1/AIAA2013-5000.pd

Input and State Estimation for Discrete-Time Linear Systems with Application to Target Tracking and Fault Detection

This dissertation first presents a deterministic treatment of discrete-time input reconstruction and state estimation without assuming the existence of a full-rank Markov parameter. Algorithms based on the generalized inverse of a block-Toeplitz matrix are given for 1) input reconstruction in the case where the initial state is known; 2) state estimation in the case where the initial state is unknown, the system has no invariant zeros, and the input is unknown; and 3) input reconstruction and state estimation in the case where the initial state is unknown and the system has no invariant zeros. In all cases, the unknown input is an arbitrary deterministic or stochastic signal. In addition, the reconstruction/estimation algorithm is deadbeat, which means that, in the absence of sensor noise, exact input reconstruction and state estimation are achieved in a finite number of steps. Next, asymptotic input and state estimation for systems with invariant zeros is considered. Although this problem has been widely studied, existing techniques are confined to the case where the system is minimum phase. This dissertation presents retrospective cost input estimation (RCIE), which is based on retrospective cost optimization. It is shown that RCIE automatically develops an internal model of the unknown input. This internal model provides an asymptotic estimate of the unknown input regardless of the location of the zeros of the plant, including the case of nonminimum-phase dynamics. The input and state estimation method developed in this dissertation provides a novel approach to a longstanding problem in target tracking, namely, estimation of the inertial acceleration of a body using only position measurements. It turns out that, for this problem, the discretized kinematics have invariant zeros on the unit circle, and thus the dynamics is nonminimum-phase. Using optical position data for a UAV, RCIE estimates the inertial acceleration, which is modeled as an unknown input. The acceleration estimates are compared to IMU data from onboard sensors. Finally, based on exact kinematic models for input and state estimation, this dissertation presents a method for detecting sensor faults. A numerical investigation using the NASA Generic Transport Model shows that the method can detect stuck, bias, drift, and deadzone sensor faults. Furthermore, a laboratory experiment shows that RCIE can estimate the inertial acceleration (3-axis accelerometer measurements) and angular velocity (3-axis rate-gyro measurements) of a quadrotor using vision data; comparing these estimates to the actual accelerometer and rate-gyro measurements provide the means for assessing the health of the accelerometer and rate gyro.PHDAerospace EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/145813/1/ansahmad_1.pd

The role of post-disaster institutions in recovery and resilience: a comparative study of three recent disasters – Victorian Bushfires (2009), Queensland Floods (2010-11), and Canterbury Earthquakes (2010-12)

This paper addresses the fourth area of disaster management: recovery and resilience. Disasters are focusing events that can drive immediate policy change. It argues that good recovery institutions provide the adaptive capacity that enables communities to recover from natural disasters. This paper briefly describes recovery processes after three natural disasters in Australia and New Zealand between 2009 and 2011: bushfires in Victoria in 2009, flooding in Queensland from 2010-2011 and earthquakes in the Canterbury region from 2010. These cases demonstrate the importance of flexible governance arrangements. This is shown through the choice of recovery institution, evidence of institutional learning before and after disasters, the role of community engagement, response to insurance issues, and the building of resilience. Particularly important for resilience is the building of relationships between recovery institutions and local governments and communities

Unsteady low-Reynolds number flow control in different regimes

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106476/1/AIAA2013-353.pd

Measurable Safety of Automated Driving Functions in Commercial Motor Vehicles

With the further development of automated driving, the functional performance increases resulting in the need for new and comprehensive testing concepts. This doctoral work aims to enable the transition from quantitative mileage to qualitative test coverage by aggregating the results of both knowledge-based and data-driven test platforms. The validity of the test domain can be extended cost-effectively throughout the software development process to achieve meaningful test termination criteria

Performance Measures of Road Infrastructure - A Life Cycle Thinking Approach

Roads have been an important asset of human society and the approach we adopt towards planning, designing, constructing, operating, and maintaining of the road infrastructure has significant consequences in the long-term for not only the humans, but all species on planet Earth. Hence, the lifecycle performance of the road infrastructure that sustain our socioeconomic development with a low environmental impact, while fulfilling their technical and functional requirements is of critical importance and needs to be improved. This thesis aims to understand the nature of the information that helps improve the performance of road infrastructure over their lifecycle and propose solutions that close the existing research gaps.This thesis is essentially divided into two parts. In the first part, it focuses on the current lifecycle thinking towards the public physical infrastructure. It carries out a survey of the literature to gain a holistic understanding of the current challenges that infrastructure faces, namely population growth, anthropogenic greenhouse gas emissions, land use and coverage change, and abiotic depletion. It then recommends potential approaches to close the identified gaps. The investigation reveals that considering the entire lifecycle of the infrastructure helps avoid partial thinking, which affects the mankind and the ecosystem adversely and results in problem shifting. It shows how the lifecycle-based methods that incorporate uncertainties help enhance the depth of understanding and decisions regarding the lifecycle performance of infrastructure. In addition, it advocates that the collaboration between and within different fields of science and practice needs to be increased to better capture the consequences of various risks and avoid adverse effects.In the second part, a systematic desk (or secondary) research and regular interactions with the Norwegian Public Road Administration (NPRA) were carried out which revealed the following research gaps to improve the environmental and economic performance of the Norwegian road networks: (1) measure environmental performance of the construction machinery over their entire lifecycle based on regionalized data, which helps increase both the resolution and exclusiveness of the results; (2) estimate lifetimes of pavements based on their technical performance, which helps in improving the validity of the results when benchmarking different pavements with respect to different criteria, e.g., environment, economy, and society, and supports the decision-making at different phases of road infrastructure projects; and (3) capture material flows and stocks of road infrastructure, which helps get an overview of the availability in terms of quantities and time of the secondary materials to theoretically substitute the virgin/primary materials. Hence, potential approaches were used by means of different methods and models, namely geographical information systems (GIS), life cycle assessment (LCA), survival analysis, decision tree model, and material flow accounting (MFA), for the three focus areas to bridge the identified gaps. Also, the Norwegian input data were applied to show the proposed approaches quantitatively. Findings from the research carried out in the second part of the thesis show that:\ub7\ua0\ua0\ua0\ua0\ua0\ua0 Although the operation phase of the construction machinery has been studied solely in most of the prior research, the investigation in this research showed that the inclusion of the other phases is equally important. This means that the production, delivery, maintenance, dismantling, waste processing, and circulation of energetic and non-energetic materials at different phases of a machine’s lifespan contribute to the overall environmental impacts. \ub7\ua0\ua0\ua0\ua0\ua0\ua0 The proposed approach to measure the durability of the pavements showed discrepancies between the maintenance records and the technical requirements and explained how different factors increased or decreased the lifetimes of pavements in different traffic classes. In addition, the results from the statistical tables (showing relative values) were transformed to absolute values to ease the readability and comparability of lifetimes between different pavements.\ub7\ua0\ua0\ua0\ua0\ua0\ua0 The amount of stock in the Norwegian road network has continuously increased and in 2017 there were about 420 Mt of road materials in-service. The growth was owing to the continuous expansion of the road networks. However, the growth in the amount of road stock was predicted to increase by 9 % – 10 % between 2018 and 2050 as well, though it was assumed that the network would not expand after 2017

Characteristics of redistributed manufacturing systems: a comparative study of emerging industry supply networks

This paper explores the characteristics of redistributed manufacturing systems within the context of emerging industry supply networks (EI SNs), with a particular focus on their structure, operations and reconfiguration dynamics. A number of factors have resulted in the redistribution of manufacturing. Within Emerging Industries, advances in process and information technologies, have changed the physical and information characteristics of components and products, and the viable production economies of scale. Further, the emergence of new specialised companies fulfilling key research, production or service roles have changed industry structure and operations, and the conventional model of value creation. Six industrial systems are examined using an Industrial System mapping methodology providing a basis for cross-case analysis, selected on the basis of representing alternative and novel evolution paths that may provide insights into the characteristics of EI SNs within a redistributed manufacturing context. Cross-case analysis suggests several generic aspects to EI SNs, including the blurring of traditional industry boundaries and the critical requirement to manage uncertainty. Alternative forms of EI SNs are observed supporting particular EI evolution paths. Further, more adaptive SNs support increased product variety, with lower inventory models enabled by enhanced production and distribution flexibility, often located closer to demand.The authors would like to acknowledge UK Research Council EPSRC, the industrial collaborators who provided access to their organisations, and their supply network, industrial and institutional partners.This is the author accepted manuscript. The final version is available from Taylor & Francis via http://dx.doi.org/10.1080/00207543.2016.121476

Measurable Safety of Automated Driving Functions in Commercial Motor Vehicles - Technological and Methodical Approaches

Fahrerassistenzsysteme sowie automatisiertes Fahren leisten einen wesentlichen Beitrag zur Verbesserung der Verkehrssicherheit von Kraftfahrzeugen, insbesondere von Nutzfahrzeugen. Mit der Weiterentwicklung des automatisierten Fahrens steigt hierbei die funktionale Leistungsfähigkeit, woraus Anforderungen an neue, gesamtheitliche Erprobungskonzepte entstehen. Um die Absicherung höherer Stufen von automatisierten Fahrfunktionen zu garantieren, sind neuartige Verifikations- und Validierungsmethoden erforderlich. Ziel dieser Arbeit ist es, durch die Aggregation von Testergebnissen aus wissensbasierten und datengetriebenen Testplattformen den Übergang von einer quantitativen Kilometerzahl zu einer qualitativen Testabdeckung zu ermöglichen. Die adaptive Testabdeckung zielt somit auf einen Kompromiss zwischen Effizienz- und Effektivitätskriterien für die Absicherung von automatisierten Fahrfunktionen in der Produktentstehung von Nutzfahrzeugen ab. Diese Arbeit umfasst die Konzeption und Implementierung eines modularen Frameworks zur kundenorientierten Absicherung automatisierter Fahrfunktionen mit vertretbarem Aufwand. Ausgehend vom Konfliktmanagement für die Anforderungen der Teststrategie werden hochautomatisierte Testansätze entwickelt. Dementsprechend wird jeder Testansatz mit seinen jeweiligen Testzielen integriert, um die Basis eines kontextgesteuerten Testkonzepts zu realisieren. Die wesentlichen Beiträge dieser Arbeit befassen sich mit vier Schwerpunkten: * Zunächst wird ein Co-Simulationsansatz präsentiert, mit dem sich die Sensoreingänge in einem Hardware-in-the-Loop-Prüfstand mithilfe synthetischer Fahrszenarien simulieren und/ oder stimulieren lassen. Der vorgestellte Aufbau bietet einen phänomenologischen Modellierungsansatz, um einen Kompromiss zwischen der Modellgranularität und dem Rechenaufwand der Echtzeitsimulation zu erreichen. Diese Methode wird für eine modulare Integration von Simulationskomponenten, wie Verkehrssimulation und Fahrdynamik, verwendet, um relevante Phänomene in kritischen Fahrszenarien zu modellieren. * Danach wird ein Messtechnik- und Datenanalysekonzept für die weltweite Absicherung von automatisierten Fahrfunktionen vorgestellt, welches eine Skalierbarkeit zur Aufzeichnung von Fahrzeugsensor- und/ oder Umfeldsensordaten von spezifischen Fahrereignissen einerseits und permanenten Daten zur statistischen Absicherung und Softwareentwicklung andererseits erlaubt. Messdaten aus länderspezifischen Feldversuchen werden aufgezeichnet und zentral in einer Cloud-Datenbank gespeichert. * Anschließend wird ein ontologiebasierter Ansatz zur Integration einer komplementären Wissensquelle aus Feldbeobachtungen in ein Wissensmanagementsystem beschrieben. Die Gruppierung von Aufzeichnungen wird mittels einer ereignisbasierten Zeitreihenanalyse mit hierarchischer Clusterbildung und normalisierter Kreuzkorrelation realisiert. Aus dem extrahierten Cluster und seinem Parameterraum lassen sich die Eintrittswahrscheinlichkeit jedes logischen Szenarios und die Wahrscheinlichkeitsverteilungen der zugehörigen Parameter ableiten. Durch die Korrelationsanalyse von synthetischen und naturalistischen Fahrszenarien wird die anforderungsbasierte Testabdeckung adaptiv und systematisch durch ausführbare Szenario-Spezifikationen erweitert. * Schließlich wird eine prospektive Risikobewertung als invertiertes Konfidenzniveau der messbaren Sicherheit mithilfe von Sensitivitäts- und Zuverlässigkeitsanalysen durchgeführt. Der Versagensbereich kann im Parameterraum identifiziert werden, um die Versagenswahrscheinlichkeit für jedes extrahierte logische Szenario durch verschiedene Stichprobenverfahren, wie beispielsweise die Monte-Carlo-Simulation und Adaptive-Importance-Sampling, vorherzusagen. Dabei führt die geschätzte Wahrscheinlichkeit einer Sicherheitsverletzung für jedes gruppierte logische Szenario zu einer messbaren Sicherheitsvorhersage. Das vorgestellte Framework erlaubt es, die Lücke zwischen wissensbasierten und datengetriebenen Testplattformen zu schließen, um die Wissensbasis für die Abdeckung der Operational Design Domains konsequent zu erweitern. Zusammenfassend zeigen die Ergebnisse den Nutzen und die Herausforderungen des entwickelten Frameworks für messbare Sicherheit durch ein Vertrauensmaß der Risikobewertung. Dies ermöglicht eine kosteneffiziente Erweiterung der Validität der Testdomäne im gesamten Softwareentwicklungsprozess, um die erforderlichen Testabbruchkriterien zu erreichen