臺灣博碩士論文加值系統

本論文提出一套新的適應性模糊可變結構控制設計方法，可用來解決某一類型非線性系統之模型參考適應問題與機器人應用上的控制問題。為避免冗長複雜的座標轉換與陷入高增益控制器結果，為此本論文引用平滑的B-spline 型式的從屬函數去設計模糊控制器以獲得十分平滑與區域性調變權值的方式，去補償系統的不確定性。被提出的控制器被證明可使被控的閉迴路系統穩定，並且確保追蹤誤差趨近於一個可事先任意定義的區間。
建立在這樣的理論基礎上，被提出來的控制法則可被引用來解決兩個在機器手臂上的控制問題: 1) 機器手臂對不確定形狀物體的外廓追蹤，與2) 應用機器手臂於工作元件上的去毛邊控制。這些控制問題的挑戰，主要在於缺乏機器手臂系統的精確知識所引發的不確定與複雜的周遭環境所致。因此原先的模糊控制被發展成適應性模糊混合位置/力控制器去實現前述的控制目的。被提出的模糊控制能補償由移動座標所下的線上時變廓形追蹤 (contour following) 命令所引起非線性項目。至於後者，控制器的結構由一個可自動決定機器手臂運動特徵的外迴路命令產生器與一個即時實現控制目的的內迴路適應性模糊混合位置/力控制器。最後本論文所提供的控制結果，顯現出相當令人滿意的控制性能。

In this dissertation, a new adaptive fuzzy control using variable structure control (VSC) concept is proposed to solve model reference adaptive control (MRAC) problems of the nonlinear systems. Instead of taking the tedious coordinate transformation and yielding a ''hard'''' high-gain
controller, we introduce smooth B-spline-type membership functions into the controller so as to compensate for the uncertainties much ''softer'''', i.e., in a much smoother and locally weighted manner. To be rigorous, it
is shown that the stability of the closed-loop system can be assured and the tracking error can globally approach to an arbitrary preset dead-zone range at the price of smaller control force.
Based on this achievement, we solve two control problems in the domain of
robotic applications: 1) robotic contour following over the profile of an uncertain object, and 2) intelligent robot deburring tasks, whose challenges mainly arise from significant uncertainties due to the imprecise knowledge of the robot manipulators and the overwhelming
complexity of the surrounding environment. As a consequence, the proposed
fuzzy controller is developed into an adaptive fuzzy hybrid
position/force control scheme to accomplish the
above-mentioned force control tasks. For the former, the proposed fuzzy
controlcan compensate for the nonlinear terms induced from
the on-line time varying contour following command expressed with respect to a moving frame over the object profile.
For the latter, the architecture of the developed control consists of an
outer-loop command generator which can automatically determine the desired robot motion profile and an inner-loop adaptive fuzzy hybrid position/force controller which can achieve the real-time control objective. At last, to demonstrate the effectiveness of the developed
controller, some computer simulation results and experimental results are shown to reveal quite satisfactory performance.

Cover
Contents
1 Introduction
1.1 Motivation
1.2 Survey of Related Research
1.3 Contributions of the Dissertation
1.4 Organization of the Dissertation
2 Variable Structure Control of Nonlinear Systems via Backstepping
2.1 Problem Formulation
2.2 Output-Feedback Variable Structure Control via Backstepping
2.3 Computer Simulation
2.4 Concluding Remarks
3 Adaptive Fuzzy Variable Structure Control of Nonlinear Systems
3.1 Mathematical Foundations
3.2 Adaptive Fuzzy Variable Structure Control
3.3 Computer Simulation
3.4 Concluding Remarks
4 Robotic contour Following over Uncertain Objects Using Adaptive Fuzzy Control
4.1 Problem Formulation
4.1.1 Moving Frame
4.1.2 Hybrid Position/Force Control
4.2 Adaptive Fuzzy Hybrid Position/Force Control
4.3 Computer Simulation
4.4 Concluding Remarks
5 Intelligent Robot Deburring Using Adaptive Fuzzy Hybrid Position/Force Control
5.1 Dynamic Model of a Deburring Robot in the Cartesian Frame
5.2 Adaptive Fuzzy Hybrid Position/Force Control of the Deburring Robot
5.2.1 Outer-Loop Command Generator
5.2.2 Inner-Loop Hybrid Position/Force Controller
5.2.3 Refinement of the Desired Contact Force
5.2.4 Adaptive Fuzzy Hybrid Control
5.3 Experiments
5.4 Concluding Remarks
6 Conclusions
Appendix A: Definition of κ(.)
Appendix B: Proof of Theorem 5.1
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