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Full-Text Articles in Engineering
Viscosity Regulation In Polymer Extrusion, Diane K. Haberbusch
Viscosity Regulation In Polymer Extrusion, Diane K. Haberbusch
ETD Archive
The interesting background and history of polymer extrusion are first introduced in this thesis. The complexity of the extrusion process is described, along with sources of disturbances. A literature review of the types of controllers that have been used for viscosity regulation in polymer extrusion is given, including the proportional-integral-derivative (PID) proportional-integral (PI) controllers. Polymer viscosity in extrusion is difficult to model accurately and its regulation is prone to disturbances. Active Disturbance Rejection Control (ADRC) is the right method for addressing the model inaccuracies and facilitates a straightforward solution to accommodate industrial needs with parameters that can be easily tuned …
On The Analysis And Design Of Disturbance Rejecter, Jason Tatsumi
On The Analysis And Design Of Disturbance Rejecter, Jason Tatsumi
ETD Archive
In this thesis, the impact of the disturbance rejecter concept and the enforced plant has been explored. In order for the active disturbance rejection controller (ADRC) to provide a reasonable alternative to the industry standard PID controller, it is necessary to develop tuning procedures capable of providing adequate performance with reasonable stability margins. A focus should be placed upon the disturbance rejecter, as it is the heart and soul of ADRC. In this thesis, transfer function analysis of the enforced plant has been performed to connect ADRC with the tools from classical control. The relationship between the gain parameter and …
Practical Solutions To The Non-Minimum Phase And Vibration Problems Under The Disturbance Rejection Paradigm, Shen Zhao
ETD Archive
This dissertation tackles two kinds of control problems under the disturbance rejection paradigm (DRP): 1) the general problem of non-minimum phase (NMP) systems, such as systems with right half plane (RHP) zeros and those with time delay 2) the specific problem of vibration, a prevailing problem facing practicing engineers in the real world of industrial control. It is shown that the DRP brings to the table a refreshingly novel way of thinking in tackling the persistently challenging problems in control. In particular, the problem of NMP has confounded researchers for decades in trying to find a satisfactory solution that is …
An Active Disturbance Rejection Control Solution For Electro-Hydraulic Servo Systems, Xiao Wang
An Active Disturbance Rejection Control Solution For Electro-Hydraulic Servo Systems, Xiao Wang
ETD Archive
The intriguing history of disturbance cancellation control is reviewed in this thesis first, which demonstrates that this unique control concept is both reasonable and practical. One novel form of disturbance cancellation, ADRC (Active Disturbance Rejection Control), attracts much attention because of its good disturbance rejection ability and simplicity in implementation. Hydraulic systems tend to have many disturbances and model uncertainties, giving us a great motivation to find out a good control method. In this thesis, electro-hydraulic servo control problem is reformulated to focus on the core problem of disturbance rejection. An ADRC solution is developed and evaluated against the industry …
A Comparative Study On Fault Detection And Self-Reconfiguration, Ning Ge
A Comparative Study On Fault Detection And Self-Reconfiguration, Ning Ge
ETD Archive
Extended State Observer (ESO) and the Alpha-Beta-Gamma Tracker are introduced and compared. In comparison, the ESO is found to be more noise resistant. The extended state used for the estimation of the general system dynamics in real time makes it suitable for fault detection. Four control schemes are proposed for self-reconfiguration upon fault detection. These schemes are Active Disturbance Rejection Control, Tracker-based Feedback Control, Fuzzy Logic Control and Tracker-based PID Control. To compare their control performance, these schemes are applied to three different applications namely Active Engine Vibration Isolation System, Three-Tank Dynamic System and MEMS Gyroscope System. The advantages and …
On Active Disturbance Rejection Control;Stability Analysis And Applications In Disturbance Decoupling Control, Qing Zheng
ETD Archive
One main contribution of this dissertation is to analyze the stability characteristics of extended state observer (ESO) and active disturbance rejection control (ADRC). In particular, asymptotic stability of the dynamic system that describes the estimation error and the closed-loop system is established where the plant dynamics is completely known. In the face of large dynamic uncertainties, the estimation error, the closed-loop tracking error, and its up to the (n-1)st order derivatives are shown to be bounded. Furthermore, it is demonstrated that the error upper bounds, in general, monotonously decrease with the observer and control loop bandwidths. The second contribution is …
Robotics Control Using Active Disturbance Rejection Control, Ousama Said Khairallah
Robotics Control Using Active Disturbance Rejection Control, Ousama Said Khairallah
ETD Archive
Conventional robotics control has been set in stone since the sixties. The world has been waiting too long for a new age of control to change the world of Robotics. Active Disturbance Rejection Control (ADRC) is a newly reformed Control methodology. It has been used, in very limited applications, as a replacement for PID control. In this thesis, I will cover the different aspects of the kinematics and dynamics of a robotic manipulator. I will also examine the feasibility of using ADRC to control a robotic manipulator. To explain ADRC, a simple example that demonstrates the concepts and theory of …