機械手臂之模型基底控制與虛實系統開發

Model-based Control of Robot Manipulators and Cyber-physical Systems Development

康志豪(Zhi-Hao Kang)

指導教授 ： 黃漢邦

國立臺灣大學/工學院/機械工程學研究所/博士(2019年)

https://doi.org/10.6342/NTU201904260

摘要

本論文旨在研究模型基底控制以及虛實整合系統的開發，以提供使用者一個友善且強健的機器人操作系統。首先，我們探討了機械手臂的三種動力學模型(剛體、操作空間以及彈性動力學)，並著重在探討數值求解逆動力學的方法，此方法相當適用在即時控制上。接著，在本論文中將透過模型基底控制解決兩個議題，分別為機械手臂的奇異點以及抑制振動。首先，我們分析了六軸擬人型機械手臂的奇異姿態，將其定義為邊界奇異點以及內部奇異點，再設計一個即時奇異點處理演算法來控制機械手臂，使其平順的穿過奇異區域。此演算法是基於作業空間動力學，使機械手臂能在零空間運動，並進出奇異區域，比傳統的閃避奇異點演算法，此方法更能增加機械手臂可用的工作空間。在抑振策略上，我們所提出的演算法是基於彈性動力學，且適用於大部分的機械手臂，其內容包含了扭矩回授控制(TF)、迭代學習控制(ILC)以及多模態強韌輸入塑形法(MMR-IS-ACE)，此方法包含了加速器(減少時間延遲)及輪廓誤差補償。這些方法在模擬與實驗中得到了驗證及比較，甚至，機械手臂能在高速往復的運動下，握持水杯並保持穩定。有了上述動力學上的應用，我們也發展加速度基底逆運動學控制，可有效的解決人機遠端操控上產生動作不連續的問題。在運動分析上，我們利用全局及局部性能量測，分析了六種類型的機械手臂。最後，我們開發了一套NTU 機器人操作系統(CPS-based)，此系統整合了驅動層、平台層、演算法層，來實現許多機器人的應用，在本論文中將展示部份的成果。它仍不斷的進化以適應新穎的技術，其功能性及可擴充性在未來具有極大的潛力。

關鍵字

機械手臂 ； 剛體動力學 ； 操作空間動力學 ； 彈性動力學 ； 奇異點 ； 零空間控制 ； 迭代學習控制 ； 輸入塑形 ； 人機互動 ； 虛實整合

並列摘要

In this dissertation, we aim to approach the model-based control and develop a cyber-physical systems (CPS) to provide users with a friendly and robust robot operating system. The three dynamic models of the robot manipulators (rigid-body, operational space and elastic-joint dynamics) are first discussed, and we focus on the numerical method to solve the inverse dynamics which is most suitable for the real-time control scheme. Then, the model-based control is used to approach on two issues, i.e., singularities and vibration suppression. First, we analyze the singularities of 6-DOF anthropomorphic manipulators, i.e., boundary singularity and internal singularity, and design a real-time singularity handling algorithm based on the operational space control that can smoothly control the robot through singular regions. The algorithm controls the manipulator moving within singular regions and back to non-singular regions, so the usable workspace is increased compared with conventional approaches. The vibration suppression strategies are based on the elastic-joint dynamics, and the proposed algorithms can be applied to most of the robot manipulators. The vibration suppression strategies include the torsional feedback control (TF), iterative learning control (ILC) and multi-mode robust input shaping with accelerator and contour error compensation (MMR-IS-ACE). The proposed algorithms have been verified and compared in the simulations and experiments. For example, the robot holds a cup of water and remains stable under high-speed repetitive motion. With the dynamics applications, we also introduce some kinematic applications for the robot operating system. The acceleration based inverse kinematic control is used to solve the discontinuity problem for human-robot teleoperation. In the kinematic analysis, we use the global and local performance measure to analyze six types of serial robot manipulators. Finally, the NTU robot operating system (CPS-based) integrates the driver, platform and algorithm layers. The system has implemented many robot applications, and some of the applications are shown in this dissertation. It is constantly evolving to adapt to novel technologies, and its functionality and extensibility have great potential in the future.

並列關鍵字

robot manipulator ； rigid-body dynamics ； operational space dynamics ； elastic-joint dynamics ； singularity ； null space control ； iterative learning control ； input shaping ； human robot interaction ； CPS

參考文獻

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