Controls and Control Theory Commons^™

Multiple Model Adaptive Control Of The Vista F-16, Michael J. Stepaniak

Theses and Dissertations

Multiple model adaptive control (MMAC) is investigated using the high-fidelity, nonlinear, six-degree-of-freedom Simulation Rapid-Prototyping Facility VISTA F-16. Detection of single actuator and sensor failures is considered, with an MMAC algorithm initially pursued which allows a controller specifically designed for each particular failure condition to replace the standard F-16 Block 40 flight control system (FCS) once the failure is detected. The synthesis of certain discrete-time LQG/PI controllers (those using control variables linearly dependent on state derivatives) is shown to be unattainable due to numerical difficulties. A novel control technique, termed control redistribution, is introduced which redistributes control commands (that would normally …

Design Of Flight Control Laws For Aircraft With Flexible Wings Using Quantitative Feedback Theory, Christina L. Osmon

Theses and Dissertations

Aircraft composed of lightweight composite materials are extremely enticing since their structural weight is greatly reduced. However, the control of these aircraft is complicated by the resultant flexibility of the wings. Two avenues of approach are possible; stiffen the wings thus losing some of the weight reduction benefits, or design the lateral/directional flight control system cognizant of the wing's flexibility. In this thesis the second approach is taken. The design of three lateral/directional flight control systems for the sub-sonic flight envelope of the F-18 is presented. The Quantitative Feedback Theory (QFT) robust control design technique is used. These designs incorporate …

Application Of Mixed-Norm Optimal Control To A Multi-Objective Active Suspension Problem, John B. Allison

Theses and Dissertations

Mixed norm optimal control synthesis is used to solve a multiobjective suspension problem. The objective is to develop a controller for an active suspension system onboard a tractor semitrailer vehicle. The problem is first approached by using H₂ and H∞ optimization. It is shown that by combining both techniques into one mixed norm optimization method, it is possible to exploit the strengths of each norm to provide superior performance. Two H₂/H∞ designs were completed. One design concentrated on optimal performance at one design condition. The second design concentrated on providing the best performance possible at a medium …

Intelligent Control Of Vehicles: Preliminary Results On The Application Of Learning Automata Techniques To Automated Highway System, Cem Unsal, John S. Bay, Pushkin Kachroo

Electrical & Computer Engineering Faculty Research

We suggest an intelligent controller for an automated vehicle to plan its own trajectory based on sensor and communication data received. Our intelligent controller is based on an artificial intelligence technique called learning stochastic automata. The automaton can learn the best possible action to avoid collisions using the data received from on-board sensors. The system has the advantage of being able to work in unmodeled stochastic environments. Simulations for the lateral control of a vehicle using this AI method provides encouraging results.

An Algorithmic Approach To Loop Shaping With Applications To Self-Tuning Control Systems, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

An algorithmic approach to feedback control design is introduced. It simplifies the existing iterative design process, which is often tedious, by reducing the design problem to solving a set of linear algebraic equations. The algorithmic nature of such an approach makes it attrative to not only off-line designs but also self-tuning control systems, where the compensators are continuously tuned on-line as the dynamics of the physical process vary with time. This is demonstrated in the example where the proposed algorithm is implemented for an industrial tension regulation system with successful simulation results. Extensions of the algorithm to …

Flexible Low-Cost Automated Scaled Highway (Flash) Laboratory For Studies On Automated Highway Systems, Pushkin Kachroo, Kaan Ozbay, Robert G. Leonard, Cem Unsal

Electrical & Computer Engineering Faculty Research

This paper addresses the development of a flexible low-cost automated scale highway (FLASH) laboratory which is intended to serve as a catalyst for accelerating the development of many intelligent vehicle highway system (IVHS) concepts. It also highlights the significance of the laboratory for the research, evaluation, and testing of automated highway system (AHS) configurations, architectures, designs and technologies. This laboratory, using small scale standardized vehicles will serve as a test bed for the economical development and evaluation of various hardware, software, and management systems before full scale testing and deployment. The laboratory will provide the capability to test day and …

Full Envelope Control Of Nonlinear Plants With Parameter Uncertainty By Fuzzy Controller Scheduling, Thomas J. Kobylarz

Theses and Dissertations

A full envelope controller synthesis technique is developed for multiple-input single-output (MISO) nonlinear systems with structured parameter uncertainty. The technique maximizes the controller's valid region of operation, while guaranteeing pre-specified transient performance. The resulting controller does not require on-line adaptation, estimation, prediction or model identification. Fuzzy Logic (FL) is used to smoothly schedule independently designed point controllers over the operational envelope and parameter space of the system's model. These point controllers are synthesized using techniques chosen by the designer, thus allowing an unprecedented amount of design freedom. By using established control theory for the point controllers, the resulting nonlinear dynamic …

Optimal Mixed-Norm Control Synthesis For Discrete-Time Linear Systems, David R. Jacques

Theses and Dissertations

A mixed-norm approach to control synthesis for discrete time linear systems is developed. Specifically, the problem of minimizing the H₂ norm of a transfer function, subject to a combination of ℓ₁ and-or H_∞ norm constraints on dissimilar but related transfer functions is considered. The uniqueness of the optimal solution is shown, and numerical methods for approximating the optimal solution to within arbitrary accuracy are developed. These methods generally result in high order compensators which can not be implemented in most practical applications. In response to this, a numerical method is developed which solves for suboptimal solutions of …

Model Parameter And Time Delay Estimation In The Frequency Domain, Aidan O'Dwyer, John Ringwood

Conference papers

This paper discusses the estimation of the parameters (including the time delay) of single input, single output (SISO) process models from an appropriate number of arbitrarily specified points on the process frequency response. The method involves combining an analytical approach with a least squares approach using a gradient algorithm, to provide accurate and robust estimates of the parameters.

An Analysis Of The Use Of Programmable Controllers To Control An In Situ Leach Mine Wellfield, Jimmy W. Stokey

Dissertations and Theses @ UNI

In situ mining is a relatively new method that has the potential of recovering a variety of minerals. This process is quickly becoming an alternative to conventional mining techniques that are environmentally unsound. Two problems associated with in situ mining are, the amount of waste water generated by the process (bleed) and the uncontrolled migration of lixiviant outside the production zone (an excursion).

The purpose of this study was to determine if in situ mining processes could be monitored and controlled with a Sequential Control and Data Acquisition (SCADA) system. Using programmable logic controllers, a cost-effective SCADA system was designed …