Design of generalized minimum variance controllers for nonlinear multivariable systems

The design and implementation of Generalized Minimum Variance control laws for nonlinear multivariable systems that can include severe nonlinearities is considered. The quadratic cost index minimised involves dynamically weighted error and nonlinear control signal costing terms. The aim here is to show the controller obtained is simple to design and implement. The features of the control law are explored. The controller obtained includes an internal model of the process and in one form is a nonlinear version of the Smith Predictor

Disturbance Observer-based Robust Control and Its Applications: 35th Anniversary Overview

Disturbance Observer has been one of the most widely used robust control tools since it was proposed in 1983. This paper introduces the origins of Disturbance Observer and presents a survey of the major results on Disturbance Observer-based robust control in the last thirty-five years. Furthermore, it explains the analysis and synthesis techniques of Disturbance Observer-based robust control for linear and nonlinear systems by using a unified framework. In the last section, this paper presents concluding remarks on Disturbance Observer-based robust control and its engineering applications.Comment: 12 pages, 4 figure

Fully pneumatic semi-active vibration isolator design and analysis

The research presented in this thesis provides a methodology of designing, modeling and controlling a fully pneumatic semi-active vibration isolator system. The prototype vibration isolator system has the ability to adjust the damping and natural frequency characteristics of the system. It consists of an air spring, a variable orifice valve, and an accumulator. In this conguration, the spring characteristics are provided by the air spring and accumulator, while the variable orifice valve provides the damping characteristics. The valve is computer regulated according to the innovative control laws that were developed for the pneumatic system. The vibration isolator system is designed to work in the vibration environment that is typically observed in the case of Class 7 and 8 vehicles as dened by the U.S Department of Transportation Federal Highway Administration. In order to design a vibration isolator system for the intended application, a benchmarking study was conducted to gain additional insight on OEM vibration isolator systems features and limitations. Based on the insights obtained from this study, the design requirements for the system were dened. This paper presents a methodology of producing a plant model that is based on supplier\u27s engineering specications and experimental characterization. The plant model includes a complete characterization of nonlinear pressure to volume and eective area to ride height relationships. A detailed design process of selecting and implementing components to optimize system performance is also provided. The plant model was then used to design three semiactive controllers that use position and pressure feedback signals that exploit the nonlinear characterizations to measure direct force generation. The semi-active controllers that were designed for this novel pneumatic vibration isolator system include: a LQI (Linear Quadratic Impulse) optimal controller, Modied Skyhook controller, and a Relative Displacement controller. This vibration isolator system was designed, fabricated, and tested using a prototype electronic height control system. A comprehensive design process for the specialized height control system is also presented.The performance of the system was evaluated using a custom testing apparatus that was built specically for this vibration isolator research. The testing apparatus was designed to accommodate dierent isolator systems and excite them with simulated road disturbances to obtain head-to-head system comparisons. This research presents a comparison between the system performances of an OEM Peterbilt cab suspension unit and the innovative fully pneumatic semi-active vibration isolator prototype using the three dierent control laws. It was found that the properly tuned controllers were able to provide desired dynamic characteristics over the range of common ride frequencies

Digital Data-Based PID Controller Design for Processes with Inverse Response

Master'sMASTER OF ENGINEERIN

Frit-based controller tuning of a dc-dc boost converter

This report presents a Fictitious Reference Iterative Tuning design for a DC-DC boost converter based on a Model-Free approach. A Fictitious Reference Iterative Tuning is a data-driven controller tuning technique that uses one-shot experimental data to construct the input controller of an undefined plant model. Fictitious Reference Iterative Tuning ensures that the plant output fits the reference model output by optimizing the performance index, which comprises a fictional reference output calculated from oneshot experimental input-output results. A DC-DC boost converter is a step-up converter with an output voltage higher than the input voltage. This converter system has a nonlinear dynamic behaviour, as it works in switch mode. The modelling of a Boost converted system is first provided to form data collection and fictitious reference signal derivation. The configuration of a nonlinear system discussed here is assumed to be known, but the parameters remain unknown. Design and simulation analyses using MATLAB software have been conducted for results validation and verification. Furthermore, we formulate the algorithm for determining the optimal controller parameters based on the Model-Free approach. Lastly, we verify and compare the proposed tuning technique’s output with any controller design techniques

Studies on Data-Driven Controller Tuning for Cascade Control Systems

13301甲第4623号博士（工学）金沢大学博士論文本文Full 以下に掲載：Journal of Robotics and Mechatronics 28(5) pp.739-744 2016. FUJI TECHNOLOGY PRESS LTD. 共著者：Huy Quang Nguyen, Osamu Kaneko, Yoshihiko Kitazak

Frequency-Domain Data-Driven Controller Synthesis for Unstable LPV Systems

Synthesizing controllers directly from frequency-domain measurement data is a powerful tool in the linear time-invariant framework. Ever-increasing performance requirements necessitate extending these approaches to account for plant variations. The aim of this paper is to develop frequency-domain analysis and synthesis conditions for local internal stability and $\mathcal{H}_\infty$-performance of single-input single-output linear parameter-varying systems. The developed synthesis procedure only requires frequency-domain measurement data of the system and does not need a parametric model of the plant. The capabilities of the synthesis procedure are demonstrated on an unstable nonlinear system.Comment: 8 pages, 8 figures, submitted in Proceedings of the 4th IFAC workshop on Linear Parameter-Varying Systems, 202

Model predictive emissions control of a diesel engine airpath: Design and experimental evaluation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163480/2/rnc5188.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163480/1/rnc5188_am.pd

A flexible mixed-optimization with H∞ control for coupled twin rotor MIMO system based on the method of inequality (MOI)- An Experimental Study

This article introduces a cutting-edge H∞ model-based control method for uncertain Multi Input Multi Output (MIMO) systems, specifically focusing on UAVs, through a flexible mixed-optimization framework using the Method of Inequality (MOI). The proposed approach adaptively addresses crucial challenges such as unmodeled dynamics, noise interference, and parameter variations. Central to the design is a two-step controller development process. The first step involves Nonlinear Dynamic Inversion (NDI) and system decoupling for simplification, while the second step integrates H∞ control with MOI for optimal response tuning. This strategy is distinguished by its adaptability and focus on balancing robust stability and performance, effectively managing the intricate cross-coupling dynamics in UAV systems. The effectiveness of the proposed approach is validated through simulations conducted in MATLAB/Simulink environment. Results demonstrated the efficiency of the proposed robust control approach as evidenced by reduced steady-state error, diminished overshoot, and faster system response times, thus significantly outperforming traditional control methods