隨著工業機械臂的應用增加，力量控制越來越受到重視，而這類力量控制也稱為順應性控制(compliant control)，順應性控制中又以阻抗控制(impedance control)最為常見。但一般的順應性控制需安裝價格不菲的力量感測器，大幅增加了此類力覺機械臂的建置成本。因此，以估測的方法取代力量感測器的方法也相繼被提出，其中又以干擾估測器(disturbance observer, DOB)最為廣用，但多用於串聯式及低自由度的機械臂中，對於並聯式機械臂的使用效果還待進一步探討。本研究將DOB使用在Delta並聯式機械臂的外力估測，其效果未如預期。因此本研究提出了一種新的外力估測方法，以阻抗控制為基礎架構，搭配系統識別(system identification, SID)及反向阻抗的概念，提出了一套不需力量感測器且可用於Delta並聯式機械臂的力量控制架構。以模擬及本研究自行設計開發的Delta機械臂驗證了所提出無感測器力量控制架構的可行性，並將此控制方法實際應用於碰撞偵測(collision detection)且得到了良好的結果。

With the increased utilization of industrial manipulators, the force control is gaining more and more attention and appreciation. The force control is also known as the compliant control. Among all proposed techniques, impedance control is the most commonly used method. The compliant control is very useful and effective especially in the situation of interaction with robots and humans, but it fundamentally requires installation of the force sensor to obtain the external force value as feedback signal. This drastically increases the cost of the implementation of such a haptic manipulator. Therefore, many researchers have proposed estimation methods to estimate the external force. Those estimation methods ease the requirement of the force sensor. The disturbance observer (DOB) is the most widely used, but has mainly applied to the series manipulator or low D.O.F. robot arms. On the other hand, the effectiveness and the performance of the force estimation applying to parallel manipulators are still not been investigated thoroughly. In this study, the external force estimation performance of DOB on the Delta robot is not as expected. Thus, a sensor-less impedance control method based on system identification (SID) and the concept of inverse objective impedance is proposed and applied. The proposed method was verified via simulation and experiments with satisfactory performance. This control scheme also applied to Delta robot for collision detection with pleasing result.

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