機器人發展的主要目的為取代人類於高風險環境下進行作業，如輻射區、海底、外太空等。隨科技的日新月異，通訊網路遠端控制機器人系統已逐漸取代傳統接線式機器人控制系統。透過由通訊網路提供的資訊共享平台，機器人系統中的感測器、控制器、致動器等元件皆可經由網路相互溝通；而本論文之架構即是建立在控制器可經由通訊網路分別接收處理不同區域機器人回傳之訊號上。然而，由於通訊網路存在許多不確定性，如時間延遲、封包遺失、封包重複等，皆影響了機器人系統的穩定性及系統性能。因此，本論文著重於討論存在時間延遲及封包遺失等通訊不確定性下，經由網路機器人控制系統的穩定性及系統性能。

本研究以被動性原理為基礎設計網路機器人系統，並利用波函數轉換(Wave-Variable Transformation)及波函數調制(Wave-Variable Modulation)確保存在時間延遲及封包遺失之通訊系統的被動性，進而維持機器人系統的穩定性。通訊網路的不確定因素除了影響機器人系統的穩定性，亦會因為封包遺失等因素導致機器人系統位置偏移(Position Drift)等問題。基於被動性原理，機器人與遠端控制器需以速度及扭矩作為傳遞訊號，使控制器必須對速度積分以估算機器人系統之位置，導致位置追蹤之誤差。故本研究所提出，基於被動特性設計機器人端控制器(Local Controller)，將速度及位置訊號結合成單一訊號傳遞至遠端控制器，以提升系統之性能。為符合現實通訊網路中離散時間之特性，本研究亦提出將系統架構延伸至離散時間系統。針對連續時間的機器人系統及離散時間的通訊網路，本文提出符合被動性的取樣與維持器(Sampler and Hold)對數位訊號及連續訊號做相互的轉換。最後，本研究以模擬與實驗之方式，提出控制系統之性能並驗證其結果。

Robotic control systems have been extensively applied in industrial operation, underwater navigation, and outer space exploration. With the rapid development of Internet, traditional robotic systems with wired connection are increasingly replaced by systems in which the robotic system and controller are connected through a communication network. Control of robotic system over communication network provides many advantage, but the signal transmission cannot be regarded as ideal, and network uncertainties time delay, packet loss, and limited communication resources constitute major challenges. The objective of this study is to develop a control algorithm for network of robotic systems achieve position regulation in the presence of communication delay and packet loss.

This thesis studies the control problem of networked robotic system by utilizing passivity approach. Wave-Variable Transformation is combined with Wave-Variable Modulation to deal with networked robotic systems under time-constant delay and packet loss. Based on passivity control theory, robotic system is passive with respect to velocity and torque as the input-output pair. Therefore the remote controller works out with the position information by integrating the velocity information. The issue of position drift would degrade performance of a robotic system due to the lack of position information in remote controller. In this thesis, a Local Controller is presented to transmit a signal containing both velocity and position information. Therefore, the position regulation can be guaranteed without the requirement of explicit position signals. Due to the discrete-time nature of communication network, the proposed control framework is extended to discrete-time system. A passive sampler and hold is used to convert the continuous-time signal form the robotic system to a discrete-time signal, and vice versa. Finally, the efficiency of the developed networked robotic system is validated via both simulation and experiment results.

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