應用陀螺儀平衡器與反力矩相消平衡器於自動導引自行車平衡控制之探討

Abstract

本論文旨在發展自動導引自行車系統，發展陀螺儀平衡器 (Gyroscopic balancer) 與反力矩相消平衡器(Reacting moment canceling balancer, RMC balancer)，設計模糊滑動模式控制器 (Fuzzy sliding-mode control, FSMC) 於自動導引自行車之平衡控制。本系統包含四個主要部分：自行車平台改裝上龍頭轉動模組與後輪驅動模組、控制系統、平衡器模組與姿態量測模組。自行車系統藉由姿態量測模組接收環境資訊，並將自行車之傾斜角、傾斜角速度與飛輪旋轉角度回授輸入至控制器中進行計算，給陀螺儀平衡器馬達輸入命令，來達成自行車的穩定平衡，並由龍頭控制模組與後輪驅動模組驅使自行車轉向與前進。 本研究利用Lagrange方程式推導裝載陀螺儀平衡器、反力矩相消平衡器的自行車動力學模型，並利用模糊滑動模式控制與PID控制理論來設計控制器。模糊滑動控制結合了滑動模式控制與模糊控制的優點，藉由滑動平面的設計，增加受控系統的強韌性；利用模糊邏輯的經驗法則進行設計控制器，大幅降低設計的複雜度，因此使用模糊滑動控制器做為自動導引自行車的平衡控制。 利用模擬驗證使用模糊滑動控制器，裝載陀螺儀平衡器的自行車可以在沒有前進的速度狀態下受干擾而能穩定平衡；裝載反力矩相消平衡器的自行車使用 PID為控制器亦能使得系統收斂至穩定狀態。實驗中利用2公升水瓶落下撞擊裝載陀螺儀平衡器的自行車，自行車雖然有傾斜角6.9˚的振盪，仍可維持平衡；自行車系統甚至可在左轉範圍40˚右轉22˚以下的條件，以前進速度為8.6 km/hr任意轉彎直行而不傾倒，證明本研究提出之FSMC控制器的抗干擾強韌性與系統穩定性。然而裝載反力矩相消平衡器的自行車，因為反力矩與重力作用互為結抗，實驗結果在自行車無前進的速度下目前只能維持4秒平衡。因此評估以陀螺儀平衡器為主，反力矩相消平衡器為輔，整合應用於自動導引平衡自行車之可行性。

In this study, we developed self-riding bicycles with a gyroscopic balancer controlled by fuzzy sliding mode control (FSMC) and a reacting moment canceling balancer (RMC balancer) controlled by PID. The riderless bicycle with the gyroscopic balancer and FSMC controller has the advantages of fast system response and relatively high robustness to disturbances. Even if hit by a bottle, filled with two liters of water, suspended 50 cm away from a pivot like a pendulum, and swung 90 degrees from its equilibrium position, the bicycle is still highly stabilized. The gyroscopic balancer is the balancer with the least mass ratio of balancer to bicycle among various bicycle balancers, and it can effectively produce a moment to prevent the bicycle from falling down. Moreover, the bicycle with the gyroscopic balancer controlled by FSMC can outperform the one with PID under highly uncertain environment. The FSMC intuitively comprehended by human operators is suitable for bicycle manipulation. It can significantly reduce the design complexity of a controller for the riderless bicycle. The design idea of FSMC is creating a sliding surface served as a balancing index which incorporates three factors, the lean angle of the bicycle, the rate of lean angle of the bicycle, and the rotation angle of the gyroscopic balancer. The bicycle dynamics models with the gyroscopic balancer and RMC balancer are proposed respectively to simulate and validate the design concept on the balancing performance of the bicycle. Finally, experiments are designed to demonstrate that the riderless bicycle system with the gyroscopic balancer remains upright and stationary under impact disturbances even when the bicycle doesn’t move forward. Furthermore, the riderless bicycle with the gyroscopic balancer can go, turn left within 40 degrees and turn right within 22 degrees without falling. However, the riderless bicycle with the RMC balancer under zero forward velocity can balance only within 4 seconds, since the reacting moment and gravity effect are antagonism. As a result, we consider the feasibility investigation on applying RMC balancer to bicycle with gyroscopic balancer to improve the stability of the self-riding bicycle system.