本論文旨在發展無力量感測器之動力輔助控制技術，藉由Luenberger觀測器與虛擬微分回授控制器為基礎之設計，同時進行伺服系統之運動狀態與外擾估測，進而取代用於動力輔助系統之力量感測器，實現無力量感測器之動力輔助控制技術。在應用上，本論文所提出之觀測器，首先結合於兩輪驅動之電動輪椅裝置；唯兩輪驅動之電動輪椅因機械結構關係，兩輪之輸出具有複雜的狀態耦合效應。為解決狀態耦合之問題，提出了基於運動座標轉換之動力輔助控制方法，實現具狀態解耦效果之動力輔助輪椅系統，並搭配動力輔助性能指標進行輔助效能驗證。接著，利用所設計之狀態與外擾觀測器，應用於循環式復健動力輔助踩車系統。循環式動力輔助踩車系統是一種廣泛使用於醫療復健工程上的輔助裝置，特別是中風或脊隨神經受損造成行動不便的患者，特別需要此裝置之輔助，也是目前復健治療較多的一群。然而在復健過程中，患者常會因下肢肌肉張力異常導致痙攣。為了避免患者因長時間之復健過程而發生痙攣現象，在踩車系統動力輔助過程中，即時監測因肌肉張力對於系統產生之交互作用力，便有其必要性。因此本研究，利用所發展之狀態與外擾估測技術，提出動力輔助踩車系統交互作用力之監測技術，並結合外擾順從之速度控制方法，實現了可隨時監視交互作用力之動力輔助踩車系統。配合應用實例分別進行系統實務驗證，實驗結果顯示，無力量感測器之動力輔助輪椅控制系統在經由運動座標轉換後，已可具體實現；同時，在無任何增設力量或扭力感測器環境下，循環式下肢復健動力輔助系統亦可即時提供復健過程所需監視的交互作用力。

This research aims to design and implement force-sensorless power-assisted control technologies. The observer design for state and disturbance estimation is the significant contribution of this research, which is proposed to facilitate the practical implementation of force-sensorless power-assisted control. The observer was developed based on the Luenberger observer and the pseudo-derivative feedback controller for obtaining the velocity, acceleration, and reactive force/torque information in power-assisted systems. With respect to practical applications, a power-assisted wheelchair integrated with the proposed observer is presented. However, power-assisted wheelchairs driven by dual electric motors comprise the two-input and two-output dynamic coupling system. Thus, the force-sensorless power-assisted wheelchair is realized with motion coordinate transformation that deals with the inherent coupling problem of dynamic output. Further, the proposed observer was also combined with a lower limb cycle ergometer, which is a typical rehabilitation power-assisted device for paraplegic patients with abnormal muscle tone in their lower limbs. Since unusual muscle tone may cause excessive spasms during rehabilitation, it is important to monitor reactive torques produced primarily by the abnormal muscle tone. The proposed observer applied to a belt-driven cycle ergometer was used to estimate reliable reactive torque with stable cycle speed control. Experimental results show that the proposed observer can effectively estimate the human force exerted on the wheelchair and reactive torque between subjects and the cycle ergometer. The force- sensorless power-assisted control was then achieved in the applications of an electric wheelchair and a cycle ergometer.

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