This thesis presents a novel design paradigm of mobile robots: the Hybrid Mobile Robot system. It consists of a combination of parallel and serially connected links resulting in a hybrid mechanism that includes a mobile robot platform for locomotion and a manipulator arm for manipulation, both interchangeable functionally. All state-of-the-art mobile robots have a separate manipulator arm module attached on top of the mobile platform. The platform provides mobility and the arm provides manipulation. Unlike them, the new design has the ability to interchangeably provide locomotion and manipulation capability, both simultaneously. This was accomplished by integrating the locomotion platform and the manipulator arm as one entity rather than two separate and attached modules. The manipulator arm can be used as part of the locomotion platform and vice versa. This paradigm significantly enhances functionality. The new mechanical design was analyzed with a virtual prototype that was developed with MSC Adams Software. Simulations were used to study the robot’s enhanced mobility through animations of challenging tasks. Moreover, the simulations were used to select nominal robot parameters that would maximize the arm’s payload capacity, and provide for locomotion over unstructured terrains and obstacles, such as stairs, ditches and ramps. The hybrid mobile robot also includes a new control architecture based on embedded on-board wireless communication network between the robot’s links and modules such as the actuators and sensors. This results in a modular control architecture since no cable connections are used between the actuators and sensors in each of the robot links. This approach increases the functionality of the mobile robot also by providing continuous rotation of each link constituting the robot. The hybrid mobile robot’s novel locomotion and manipulation capabilities were successfully experimented using a complete physical prototype. The experiments provided test results that support the hypothesis on the qualitative and quantitative performance of the mobile robot in terms of its superior mobility, manipulation, dexterity, and ability to perform very challenging tasks. The robot was tested on an obstacle course consisting of various test rigs including man–made and natural obstructions that represent the natural environments the robot is expected to operate on.

This thesis presents a novel design paradigm of mobile robots: the Hybrid Mobile Robot system. It consists of a combination of parallel and serially connected links resulting in a hybrid mechanism that includes a mobile robot platform for locomotion and a manipulator arm for manipulation, both interchangeable functionally. All state-of-the-art mobile robots have a separate manipulator arm module attached on top of the mobile platform. The platform provides mobility and the arm provides manipulation. Unlike them, the new design has the ability to interchangeably provide locomotion and manipulation capability, both simultaneously. This was accomplished by integrating the locomotion platform and the manipulator arm as one entity rather than two separate and attached modules. The manipulator arm can be used as part of the locomotion platform and vice versa. This paradigm significantly enhances functionality. The new mechanical design was analyzed with a virtual prototype that was developed with MSC Adams Software. Simulations were used to study the robot’s enhanced mobility through animations of challenging tasks. Moreover, the simulations were used to select nominal robot parameters that would maximize the arm’s payload capacity, and provide for locomotion over unstructured terrains and obstacles, such as stairs, ditches and ramps. The hybrid mobile robot also includes a new control architecture based on embedded on-board wireless communication network between the robot’s links and modules such as the actuators and sensors. This results in a modular control architecture since no cable connections are used between the actuators and sensors in each of the robot links. This approach increases the functionality of the mobile robot also by providing continuous rotation of each link constituting the robot. The hybrid mobile robot’s novel locomotion and manipulation capabilities were successfully experimented using a complete physical prototype. The experiments provided test results that support the hypothesis on the qualitative and quantitative performance of the mobile robot in terms of its superior mobility, manipulation, dexterity, and ability to perform very challenging tasks. The robot was tested on an obstacle course consisting of various test rigs including man–made and natural obstructions that represent the natural environments the robot is expected to operate on.

This thesis investigates using processor-in-loop techniques with non-real-time electro-magnetic transient simulation software for designing microcontroller-based systems. The behaviour of a microcontroller is included in the simulation by directly integrating the target microcontroller into an EMTP co-simulation. Additionally, to assist the design process, the optimization functionality of the EMTP program is extended to the microcontroller algorithm. Since non-realtime simulation does not require specialized test hardware to accurately simulate systems, it is both cheaper and able to be used earlier in the controller design process then hardware-in-loop real-time simulation. A component is created in the PSCAD / EMTDC program to integrate a generic controller running an arbitrary periodic algorithm into an EMTP simulation. The component operation is verified by creating a co-simulation of a three-phase induction motor V / f. speed control. The co-simulation results match the behaviour of the resulting system under a fairly broad range of operating conditions, highlighting the applicability of the technique.

This thesis investigates using processor-in-loop techniques with non-real-time electro-magnetic transient simulation software for designing microcontroller-based systems. The behaviour of a microcontroller is included in the simulation by directly integrating the target microcontroller into an EMTP co-simulation. Additionally, to assist the design process, the optimization functionality of the EMTP program is extended to the microcontroller algorithm. Since non-realtime simulation does not require specialized test hardware to accurately simulate systems, it is both cheaper and able to be used earlier in the controller design process then hardware-in-loop real-time simulation. A component is created in the PSCAD / EMTDC program to integrate a generic controller running an arbitrary periodic algorithm into an EMTP simulation. The component operation is verified by creating a co-simulation of a three-phase induction motor V / f. speed control. The co-simulation results match the behaviour of the resulting system under a fairly broad range of operating conditions, highlighting the applicability of the technique.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Systems Science and Industrial Engineering, 2007. / Includes bibliographical references.

In this thesis, we conduct a preliminary study on the controller design for directional antenna devices carried by drones. The goal of the control system is to ensure the best alignment between two directional antennas so as to enhance the performance of air-to-air communication between the drones. The control system at the current stage relies on the information received from GPS devices. The control system includes two loops: velocity loop and position loop to suppress wind disturbances and to assure the alignment of two directional antennae. The simulation and animation of directional antennae alignment control for two-randomly moving drones was developed using SIMULINK. To facilitate RSSI-based antenna alignment control to be conducted in the future work, a study on initial scanning techniques is also included at the end of this thesis.

The present thesis deals with the analysis of Environmental Control System (ECS) as a part of the aircraft conceptual design. The research focuses on developing methods for modelling, simulation and optimization of current and future cooling technologies suitable for aircraft applications. The work started with a pre-study in order to establish the suitability of different cooling technologies for ECS application. Therefore, five technologies namely, Bootstrap (BS), Reverse-Bootstrap (RBS), vapour cycle system (VCS), magnetic cooling (MC) and thermo-electric cooling (EC), were assessed from a theoretical point of view by the method of benchmarking. This resulted into the selection of three most suitable technologies that were further modelled and simulated in Dymola. In order to compare the optimum designs for each technology, the models were optimized using the modeFRONTIER software. The comparison was performed based on the optimum ratio of maximum power of cooling and minimum fuel penalty. The results showed that VCS has the “best” performances compared to BS and RBS. In addition to the active technologies, passive cooling methods such as liquid cooling by means of jet-fuel and poly-alpha-olefin were considered to address high heat transfer rates. In order to apply the cooling technologies in the ECS, concept system architectures were formulated using the functional analysis. This led to the identification of basic functions, components and sub-systems interaction. Based on the comparison carried out previously and the functional analysis, two ECS architectures were developed. Design optimization procedure was applied further in order to assess each concept and also to study the differences between the two concept architectures. The results depict the complex interaction of different key parameters of the architectures and their influence on the outcome. The study culminated with a proposed methodology for formulation of systems architecture using information from the optimization results and a robust functional analysis method. To sum up, the thesis proposes a simulation-based optimization method that allows inclusion of ECS system in aircraft conceptual design phase. The study also proves the complexity of the conceptual design stage for ECS architectures which highly influences the design of the combat aircraft.

Includes bibliography. / Successful multivariable control system design demands knowledge, skill and creativity of the designer. The goal of the research described in this dissertation was to investigate, implement, and evaluate methods by which artificial intelligence techniques, in a broad sense, may be used in a design system to assist the user. An intelligent, interactive, control system design tool has been developed to fulfil this aim. The design tool comprises two main components; an expert system on the upper level, and a powerful CACSD package on the lower level. The expert system has been constructed to assist and guide the designer in using the facilities provided by the underlying CACSD package. Unlike other expert systems, the user is also aided in formulating and refining a comprehensive and achievable design specification, and in dealing with conflicts which may arise within this specification. The assistance is aimed at both novice and experienced designers. The CACSD package includes a synthesis program which attempts to find a controller that satisfies the design specification. The synthesis program is based upon a recent factorization theory approach, where the linear multivariable control system design problem is translated into, and techniques efficiency solved as, a quadratic programming problem, which significantly improve the time and space of this method have been developed, making it practical to solve substantial multivariable design problems using only a microcomputer. The design system has been used by students at the University of Cape Town. Designs produced using the expert system tool are compared against those produced using classical design methods.

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Modern control theory is today an interdisciplinary area of research. Just as much as this can be problematic, it also provides a rich research environment where practice and theory meet. This Thesis is conducted in the borderline between computing science (numerical analysis) and applied control theory. The design and analysis of a modern control system is a complex problem that requires high qualitative software to accomplish. Ideally, such software should be based on robust methods and numerical stable algorithms that provide quantitative as well as qualitative information. The introduction of the Thesis is dedicated to the underlying control theory and to introduce the reader to the main subjects. Throughout the Thesis, the theory is illustrated with several examples, and similarities and differences between the terminology from mathematics, systems and control theory, and numerical linear algebra are highlighted. The main contributions of the Thesis are structured in two parts, dealing with two mainly unrelated subjects. Part I is devoted to the qualitative information which is provided by the stratification of orbits and bundles of matrices, matrix pencils and system pencils. Before the theory of stratification is established the reader is introduced to different canonical forms which reveal the system characteristics of the model under investigation. A stratification reveals which canonical structures of matrix (system) pencils are near each other in the sense of small perturbations of the data. Fundamental concepts in systems and control, like controllability and observability of linear continuous-time systems, are considered and it is shown how these system characteristics can be investigated using the stratification theory. New results are presented in the form of the cover relations (nearest neighbours) for controllability and observability pairs. Moreover, the permutation matrices which take a matrix pencil in the Kronecker canonical form to the corresponding system pencil in (generalized) Brunovsky canonical form are derived. Two novel algorithms for determining the permutation matrices are provided. Part II deals with numerical methods for solving periodic Riccati differential equations (PRDE:s). The PRDE:s under investigation arise when solving the linear quadratic regulator (LQR) problem for periodic linear time-varying (LTV) systems. These types of (periodic) LQR problems turn up for example in motion planning of underactuated mechanical systems, like a humanoid robot, the Furuta pendulum, and pendulums on carts. The constructions of the nonlinear controllers are based on linear versions found by stabilizing transverse dynamics of the systems along cycles. Three different methods explicitly designed for solving the PRDE are evaluated on both artificial systems and stabilizing problems originating from experimental control systems. The methods are the one-shot generator method and two recently proposed methods: the multi-shot method (two variants) and the SDP method. As these methods use different approaches to solve the PRDE, their numerical behavior and performance are dependent on the nature of the underlying control problem. Such method characteristics are investigated and summarized with respect to different user requirements (the need for accuracy and possible restrictions on the solution time). / Modern reglerteknik är idag i högsta grad ett interdisciplinärt forskningsområde. Lika mycket som detta kan vara problematiskt, resulterar det i en stimulerande forskningsmiljö där både praktik och teori knyts samman. Denna avhandling är utförd i gränsområdet mellan datavetenskap (numerisk analys) och tillämpad reglerteknik. Att designa och analysera ett modernt styrsystem är ett komplext problem som erfordrar högkvalitativ mjukvara. Det ideala är att mjukvaran består av robusta metoder och numeriskt stabila algoritmer som kan leverera både kvantitativ och kvalitativ information.Introduktionen till avhandlingen beskriver grundläggande styr- och reglerteori samt ger en introduktion till de huvudsakliga problemställningarna. Genom hela avhandlingen illustreras teori med exempel. Vidare belyses likheter och skillnader i terminologin som används inom matematik, styr- och reglerteori samt numerisk linjär algebra. Avhandlingen är uppdelade i två delar som behandlar två i huvudsak orelaterade problemklasser. Del I ägnas åt den kvalitativa informationen som ges av stratifiering av mångfalder (orbits och bundles) av matriser, matrisknippen och systemknippen. Innan teorin för stratifiering introduceras beskrivs olika kanoniska former, vilka var och en avslöjar olika systemegenskaper hos den undersökta modellen. En stratifiering ger information om bl.a. vilka kanoniska strukturer av matrisknippen (systemknippen) som är nära varandra med avseende på små störningar i datat. Fundamentala koncept i styr- och reglerteori behandlas, så som styrbarhet och observerbarhet av linjära tidskontinuerliga system, och hur dessa systemegenskaper kan undersökas med hjälp av stratifiering. Nya resultat presenteras i form av relationerna för täckande (närmsta grannar) styrbarhets- och observerbarhets-par. Dessutom härleds permutationsmatriserna som tar ett matrisknippe i Kroneckers kanoniska form till motsvarande systemknippe i (generaliserade) Brunovskys kanoniska form. Två algoritmer för att bestämma dessa permutationsmatriser presenteras. Del II avhandlar numeriska metoder för att lösa periodiska Riccati differentialekvationer (PRDE:er). De undersökta PRDE:erna uppkommer när ett linjärt kvadratiskt regulatorproblem för periodiska linjära tidsvariabla (LTV) system löses. Dessa typer av (periodiska) regulatorproblem dyker upp till exempel när man planerar rörelser för understyrda (underactuated) mekaniska system, så som en humanoid (mänsklig) robot, Furuta-pendeln och en vagn med en inverterad (stående) pendel. Konstruktionen av det icke-linjära styrsystemet är baserat på en linjär variant som bestäms via stabilisering av systemets transversella dynamik längs med cirkulära banor. Tre metoder explicit konstruerade för att lösa PRDE:er evalueras på både artificiella system och stabiliseringsproblem av experimentella styrsystem. Metoderna är sk. en- och flerskotts metoder (one-shot, multi-shot) och SDP-metoden. Då dessa metoder använder olika tillvägagångssätt för att lösa en PRDE, beror dess numeriska egenskaper och effektivitet på det underliggande styrproblemet. Sådana metodegenskaper undersöks och sammanfattas med avseende på olika användares behov, t.ex. önskad noggrannhet och tänkbar begränsning i hur lång tid det får ta att hitta en lösning.