雙臂行動式機器人在複雜環境之路徑規劃

Motion Planning of a Dual-Arm Mobile Robot in Complex Environments

蔡乙至(Yi-Chih Tsai)

指導教授 ： 黃漢邦

國立臺灣大學/工學院/機械工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.02035

摘要

本文主要的目的在設計與建立一個機器手臂的自動領導系統，使其能在大部分的環境中運作，例如在家庭中的廚房、工廠自動化…等等。此外我們還透過動態環境演算法來延伸成雙臂的路徑規劃，藉此強化機器人的工作效率。
首先在這篇論文中，我們提出一個關於在狀態空間的運動規劃演算法。它能克服一些困難的靜態環境的運動規劃的問題。由於是採用任意時間規劃(anytime planning)形式，所以在運算時間有限的時候還可以不斷的回傳部份運算完成的軌跡。此外Multi-RRTs 更是利用這項不斷重新規劃軌跡的特點來調整演算法的參數。
然後我們針對在動態環境的軌跡規劃的問題,提出一個CT-RRTs(Bi-direction RRTs in Configuration Time space)演算法，藉由此演算法能使的機械手臂能在部分已知的動態環境中成功的到達目標點。然而此演算法的是在不斷擴大的狀態-時間的空間中做規劃，其中機械手臂組態空間資訊以及移動物體的位置資訊都包含在狀態-時間的空間中。並且利用多種技術去加速規劃的時間以及增強它的安全性。最後我們利用CT-RRTs去發展雙臂的運動規劃，並且將運動規劃的問題推廣至更高階。
實驗部份分為模擬與實作。模擬部分建立一多功能的軟體平台，並且利用虛擬實境的方法來建造環境以及顯現模擬結果。在實作上，整合了影像系統以及馬達控制模組。整體系統可以在靜態環境中即時引導機械手臂。

關鍵字

路徑規劃 ； 軌跡規劃 ； 運動規劃 ； 雙臂式機器人

並列摘要

The main objective of this thesis is to develop an autonomous navigation system for robot arms, which can operate in most of environments, such as kitchen, factory, etc. Furthermore, by extending our planner into a dual-arm planner, we can enhance the work efficiency of the robot.
To begin with, we propose an algorithm about motion planning in the state space. It can overcome some difficult planning problems in static environments. Due to the anytime planning fashion, the partial plan can also be returned when deliberation time is limited. Further, the Multi-RRTs algorithm uses this advantage of continuously re-planning to adjust the parameters.
Next, in order to solve the problem of planning in the dynamic environments, we proposed a CT-RRTs (Bi-direction RRTs in Configuration Time space) planner, which can make the robot arm reach goal successfully in the partially known dynamic environment. However it plans in the augmented state-time space of robot arm configuration and the positions of moving objects. Various techniques are used to accelerate planning and enhance its safety.
Finally, we utilize the new planner to develop the dual-arm planner, and it can be used as the basis to solve higher level problems in motion planning.
A software platform is developed for both simulation and for real-world navigation, where environment and planning results are visualized in 3D. In real-world implementation, a vision module for distance measurement and a motor control module are integrated. In our experiments, the system is able to navigate the robot arm in static environments in real time.

並列關鍵字

path planning ； planning ； motion planning ； RRT ； CT-RRTs ； manipulator

參考文獻

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