本文介紹了基於模糊邏輯控制器設計通過實施領導者和跟隨者的方法，該方法允許建立和維護沿著給定軌跡移動之輪式移動機器人（WMR）的構造。 作為一組研究，控制器基於模糊邏輯控制器（FLC）設計，用於將移動機器人保持在所需的形式中。本論文考慮了領導者和跟隨者形成方法，模糊邏輯控制器將通過計算用於將移動機器人保持在列隊中的期望距離和期望角度來幫助維持移動機器人的構造。

This thesis presents the design of a fuzzy logic-based control by implementing the leader-follower approach that allows in establishing and maintaining the formations for the wheeled mobile robots (WMR) which moves along a predefined trajectory. As a set of research, th controller is designed based on the fuzzy logic controller (FLC) for keeping the mobile robots in the required formation. Leader-follower formation approach is considered for this thesis. Fuzzy logic controller will help in maintaining the formations of the mobile robots by calculating the desired distance and the desired angle for keeping the mobile robots in the formation.

Contents	
Abstract in Chinese…………………………………………	  I
Abstract in English………………………………….……….	 II
Contents……………………………………………..….……	 III
List of Figures………………………………………………..	 V
1. Introduction………………………………………………..	 1
  1.1 Motivation………………………………….…..……….	 1
  1.2 Problem Statement…………………………………...…	 4
  1.3 Background………….…………………………………...	 5
  1.4 Literature Review…………………………………....…..	 6
2. Mobile Robot Modelling……………………………....…...	 9
  2.1 Kinematic Model…………………………………….…..	 9
  2.2 Leader-Follower Modelling…………………………..…	13
3. Control Strategies……………………………………….….	15
  3.1 Fuzzy Logic Controller………………………………......	15
3.1.1 Fuzzy Control………………………………….…..	15
3.1.2 Membership Function (MF)………………….…....	16
     3.1.2.1 Triangular Membership Function……...….	17
     3.1.2.2 Trapezoidal Membership Function…..........	18
3.1.3 Fuzzy Inference Systems………………………......	19
3.1.4	Defuzzification…………………………………….	19
4. Simulation Results…………………………………………..	21
5. Conclusion & Future Work…………………………………	28
6. References……………………………………………………	29











List of Figures	
	
1.1 Biological examples of multi agent systems in nature:
   (A)fireflies, (B)neuron firing, (C) flocking of migrating  
   birds and, (D)fish schooling……………………………….	 
 2
1.2 Examples of formation in practice applications:
   (a)Unmanned Air Vehicles (UAVs), (b) Autonomous 
   Underwater Vehicles, (c) Mobile Robots Systems (MRSs),    
   (d) Manipulation……………………………………………	 

 3
	
2.1 Unicycle Mobile Robot [25]………………………………	10
2.2	 Schematic of Leader-Follower Formation [22]…………...	13
	
3.1 Types of membership functions:	
(a)	triangular and (b) trapezoidal [31]……………………...	18
3.2 Process for the working of a fuzzy logic controller [31]…..	19
	
4.1 input-output of the FLC……………………………………	23
4.2 Membership function of the input variable(distance_error).	24
4.3 Membership function of the input variable (angle_error)…	24
4.4 Membership function of the output variable (v)…………..	25
4.5 Membership function of the output variable (w)…………..	25
4.6 Fuzzy Rule Base for the Controller………………………...	26
4.7 Graphical surface for the input-output variables…………...	26
4.8 Fuzzy Implication and Defuzzification Process…………...	27

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