Access Type
Open Access Dissertation
Date of Award
January 2024
Degree Type
Dissertation
Degree Name
Ph.D.
Department
Chemical Engineering and Materials Science
First Advisor
Helen Durand
Abstract
Continuing advances and new applications in manufacturing and the systems engineering field lead to increased demands on controllers, models, simulation tools, and computer systems. Utilizing these new technologies can have profound consequences on control of the physical system itself, and the interactions between these aspects will need to be understood to ensure economic efficiency, safety, and secure operation. It is not always clear how implementing new technologies will impact the control of a process, especially when the modes of operation of the technology or the process itself are unusual or unknown. To address this, the work presented in this thesis considers this topic from several aspects. We focus on describing new modeling and simulation techniques, the implementation of a new kind of computer technology (quantum computing), and control of manufacturing in novel areas (e.g., in space applications).
First, we look to modeling techniques to demonstrate how several high-fidelity simulation and test bed methods can be utilized to improve controller operation, understand processes at a deeper level, and predict the consequences of cyberattacks on the structural elements of the process. There are three simulated processes in this work. The first is a simulation of a steam methane reforming reactor, which produces hydrogen from mostly methane and water vapor; the second process is powder bed fusion, which is an additive manufacturing method that creates metal objects by melting successive layers in a bed of powder; and the third is a greenhouse supplemental lighting control system. With these simulations, we elucidate understanding of how to simulate new model-based control strategies relating to the physical structure of the process, how to utilize different software for accomplishing the simulation of controllers, how to represent unusual operation such as cyberattacks on controllers, and how to use such models for increasing knowledge of a process.
Secondly, given increased interest in quantum computers, we discuss the implementation of control algorithms on quantum devices. Quantum computers utilize concepts from quantum mechanics, such as superposition and entanglement, to perform operations in new and potentially useful ways. Because of the unique ways in which quantum computers operate, which may introduce effects such as non-determinism and rounding, we consider how the operation of a controller may need to be changed to ensure safe operation of a process. To study this, we perform a theoretical analysis to study rounding effects using Lyapunov-based economic model predictive control (LEMPC), which is an advanced model-based control strategy, as well as practical aspects such as ensuring safe operation given non-deterministic controller operation. Additionally, to gain any advantage on quantum computers, quantum algorithms will need to operate in fundamentally new ways. We discuss how a controller might be implemented, to demonstrate how a controller might be non-deterministic, and we discuss the use of a quantum amplitude amplification algorithm for solving the optimization problem in a model-based controller, utilizing a specific single-input single-output system as a case study.
Finally, the last topic discussed in this thesis relates to the control of space manufacturing. Given the lengthy distances in space, it is likely necessary to have on-site manufacturing capabilities to ensure the safety and flexibility of long-term missions. Given the ample computational power available on Earth, it may be desired to utilize these resources for performing advanced control computations involving modeling or optimization for a process located in space. In this case, the significant distances in space would also impact control operation. To address this, we perform a LEMPC theoretical analysis considering communication delay, which occurs in two directions, as well as a discussion of how controllers and processes might be modified to account for such delays. The final topic in this section discusses challenges in reducing communication time, specifically by looking at quantum entanglement. Through a series of proposed methods, we describe how the communication delay will not be overcome and will remain a challenge for space-based control.
Recommended Citation
Nieman, Kip, "Advances In Control Strategies For Cyberphysical Systems Incorporating Quantum Computing, High-Fidelity Simulation Methods, And Space Communication Concerns" (2024). Wayne State University Dissertations. 4027.
https://digitalcommons.wayne.edu/oa_dissertations/4027
