Feedback Linearization Of Dynamical Systems With Modulated States For Harnessing Water Wave Power

As pointed out by other researchers, hybrid structures in ocean engineering are based on flat concrete foundations. Due to wave action these foundations are exposed to different pressure distributions on the top and bottom sides. As a result, the bottom side is exposed to a saddle type pressure distribution leading to huge forces on the foundation. Indeed, such huge forces have been observed at a number of offshore platforms installed in the North Sea. In an attempt to turn a problem into an advantage, the concept in this work aims to develop an integrated system to harness and harvest ocean wave energy right at the seabed. The long-term interest is to develop integrated devices that can be used as actuators or sensors, which, due to low manufacturing cost, can be employed in large quantities for control of ocean engineering systems, e.g., maritime renewable power-plants, or monitoring of marine processes, e.g., oceanographic sensing. A key element to the proposed system is the nonlinear coupled electromechanical oscillator unit, the dynamics of which are investigated with a novel approach in this work. The fundamental nature of the oscillator at hand makes it an excellent choice for applications involving oceanic transducers consisting of a dry driving electrical stator physically separated from a wet-driven payload mechanism. Without such units available at a low cost and a large number, harvesting the energy of a vibrating plate at seabed may prove impractical.

As pointed out by other researchers, hybrid structures in ocean engineering are based on flat concrete foundations. Due to wave action these foundations are exposed to different pressure distributions on the top and bottom sides. As a result, the bottom side is exposed to a saddle type pressure distribution leading to huge forces on the foundation. Indeed, such huge forces have been observed at a number of offshore platforms installed in the North Sea. In an attempt to turn a problem into an advantage, the concept in this work aims to develop an integrated system to harness and harvest ocean wave energy right at the seabed. The long-term interest is to develop integrated devices that can be used as actuators or sensors, which, due to low manufacturing cost, can be employed in large quantities for control of ocean engineering systems, e.g., maritime renewable power-plants, or monitoring of marine processes, e.g., oceanographic sensing. A key element to the proposed system is the nonlinear coupled electromechanical oscillator unit, the dynamics of which are investigated with a novel approach in this work. The fundamental nature of the oscillator at hand makes it an excellent choice for applications involving oceanic transducers consisting of a dry driving electrical stator physically separated from a wet-driven payload mechanism. Without such units available at a low cost and a large number, harvesting the energy of a vibrating plate at seabed may prove impractical.

In a government-aided research project carried out at Cochin University, the inventor of the Water-Train demonstrated that his invention requires only 24 BTU/ton-km of energy whereas barges use 328 BTU in the same Inland water transportation situation. The use of this Water-Train can invariably curtail, to a large extent, the emission of greenhouse gasses thereby decreasing the effect on global warming. Conventional water vehicles use screw propellers which have high reacting energy loss in propulsion whereas the Water-Train relies on the earth for reaction which is an infinite mass causing no reacting energy loss at all. The propelled water takes away a large quantity of kinetic energy (1/22 where its mass is and velocity is ). Water-Train requires a monorail rigidly fixed to the earth through cross arms and pillars for applying the traction/propulsion force. The reacting body is the earth and so the traction efficiency tends toward 100%. It utilizes low friction of water and also the vehicles are connected serially like a locomotive and hence the wave making and skin resistances are also reduced. The NITIE study conducted earlier in India showed that diesel and electric trains use 166.3 BTU and 105.76 BTU, respectively, for the same purpose.

The use of environmental data to support science, technology, and marine operations has evolved dramatically owing to long-term ocean observatories, unmanned platforms, satellite and coastal remote sensing, data assimilative numerical models, and high-speed communications. Actionable environmental information is regularly produced and communicated from quality-controlled measurements and skillful forecasts. The characterization of complex oceanographic processes is more difficult compared to inland features because of the difficulty in obtaining observations from often remote and hazardous locations. Regardless, coastal and ocean engineering projects and operations require the collection and analysis of meteorological and oceanographic data to fill information gaps and the running of numerical models to characterize regions of interest. Data analytics are also essential to integrate disparate marine data from national archives, in situ sensors, imagery, and numerical models to meet project requirements. Holistic marine environmental characterization is essential for data-driven decision making across the science and engineering lifecycle (e.g., research, production, operations, end-of-life). Many marine science and technology projects require the employment of an array of instruments and models to characterize spatially and temporally variable processes that may impact operations. Since certain environmental conditions will contribute to structural damage or operational disturbances, they are described using statistical parameters that have been standardized for engineering purposes. The statistical description should describe extreme conditions as well as long- and short-term variability. These data may also be used to verify and validate models and simulations. Environmental characterization covers the region where engineering projects or maritime operations take place. For vessels that operate across a variety of seaways, marine databases and models are essential to describe environmental conditions. Data, which are used for design and operations, must cover a sufficiently long time period to describe seasonal to sub-seasonal variations, multi-year, decadal, multi-decadal, and even climatological factors such as sea level rise, coastal winds, waves, and global ocean temperatures. Combined data types are essential for the computation of environmental loads for the region of interest. Typical factors include winds, waves, currents, and tides. Some regions may require consideration of biofouling, earthquakes, ice, salinity, soil conditions, temperature, tsunami, and visibility. Observations are also used for numerical forecasts, but errors may exist due to inexact physical assumptions and/or inaccurate initial data, which can cause errors to grow to unacceptable levels with increased forecasting times. Overall, marine environmental characterization tools, from observational data to numerical modeling, are critical to today's science, engineering, and marine operational disciplines.

The essential introduction to the principles and applications of feedback systems—now fully revised and expanded This textbook covers the mathematics needed to model, analyze, and design feedback systems. Now more user-friendly than ever, this revised and expanded edition of Feedback Systems is a one-volume resource for students and researchers in mathematics and engineering. It has applications across a range of disciplines that utilize feedback in physical, biological, information, and economic systems. Karl Åström and Richard Murray use techniques from physics, computer science, and operations research to introduce control-oriented modeling. They begin with state space tools for analysis and design, including stability of solutions, Lyapunov functions, reachability, state feedback observability, and estimators. The matrix exponential plays a central role in the analysis of linear control systems, allowing a concise development of many of the key concepts for this class of models. Åström and Murray then develop and explain tools in the frequency domain, including transfer functions, Nyquist analysis, PID control, frequency domain design, and robustness. Features a new chapter on design principles and tools, illustrating the types of problems that can be solved using feedback Includes a new chapter on fundamental limits and new material on the Routh-Hurwitz criterion and root locus plots Provides exercises at the end of every chapter Comes with an electronic solutions manual An ideal textbook for undergraduate and graduate students Indispensable for researchers seeking a self-contained resource on control theory

The sliding mode control methodology has proven effective in dealing with complex dynamical systems affected by disturbances, uncertainties and unmodeled dynamics. Robust control technology based on this methodology has been applied to many real-world problems, especially in the areas of aerospace control, electric power systems, electromechanical systems, and robotics. Sliding Mode Control and Observation represents the first textbook that starts with classical sliding mode control techniques and progresses toward newly developed higher-order sliding mode control and observation algorithms and their applications. The present volume addresses a range of sliding mode control issues, including: *Conventional sliding mode controller and observer design *Second-order sliding mode controllers and differentiators *Frequency domain analysis of conventional and second-order sliding mode controllers *Higher-order sliding mode controllers and differentiators *Higher-order sliding mode observers *Sliding mode disturbance observer based control *Numerous applications, including reusable launch vehicle and satellite formation control, blood glucose regulation, and car steering control are used as case studies Sliding Mode Control and Observation is aimed at graduate students with a basic knowledge of classical control theory and some knowledge of state-space methods and nonlinear systems, while being of interest to a wider audience of graduate students in electrical/mechanical/aerospace engineering and applied mathematics, as well as researchers in electrical, computer, chemical, civil, mechanical, aeronautical, and industrial engineering, applied mathematicians, control engineers, and physicists. Sliding Mode Control and Observation provides the necessary tools for graduate students, researchers and engineers to robustly control complex and uncertain nonlinear dynamical systems. Exercises provided at the end of each chapter make this an ideal text for an advanced course taught in control theory.

Dynamic optimization is rocket science – and more. This volume teaches researchers and students alike to harness the modern theory of dynamic optimization to solve practical problems. These problems not only cover those in space flight, but also in emerging social applications such as the control of drugs, corruption, and terror. This volume is designed to be a lively introduction to the mathematics and a bridge to these hot topics in the economics of crime for current scholars. The authors celebrate Pontryagin’s Maximum Principle – that crowning intellectual achievement of human understanding. The rich theory explored here is complemented by numerical methods available through a companion web site.

Nonlinear dynamics has been enjoying a vast development for nearly four decades resulting in a range of well established theory, with the potential to significantly enhance performance, effectiveness, reliability and safety of physical systems as well as offering novel technologies and designs. By critically appraising the state of the art, it is now time to develop design criteria and technology for new generation products/processes operating on principles of nonlinear interaction and in the nonlinear regime, leading to more effective, sensitive, accurate, and durable methods than what is currently available. This new approach is expected to radically influence the design, control and exploitation paradigms, in a magnitude of contexts. With a strong emphasis on experimentally calibrated and validated models, contributions by top-level international experts will foster future directions for the development of engineering technologies and design using robust nonlinear dynamics modelling and analysis.