群組機器人的通訊與環境探測

Abstract

機器人可以代替人類在複雜環境下執行各種工作，在人類嘈雜擠塞的居住環境中，衛星GPS設備雖然足以提供城市街道的分佈資訊，但是機器人仍需瞭解建築物的室內隔間與未知障礙物的分佈，建立該空間的平面圖，才能設計出適合的移動路徑。然而，比起單一機器人，由多個機器人所組成的群組機器人團隊更適合在複雜的環境下工作，機器人之間透過無線通訊的方式，彼此協調分工合作，不僅效率較高，也提升了容錯率。因此，對於群組機器人系統而言，工作效率與任務達成與否，是建立在機器人彼此之間的通訊品質，也就是說，群組機器人在移動狀態之下須維持良好的通訊網路狀態。

本論文設計之群組機器人團隊，搭載ZigBee無線感測網路(WSN)，利用調整接收訊號強度指標(RSSI)的概念，維持機器人之間適當的距離去執行任務，並且配合避障機制，讓群組機器人團隊能應變環境中的障礙物去調整其隊形。我們先使用電腦模擬，呈現群組機器人在探索未知環境時的移動過程，經過計算後設計出每一個機器人的移動路徑。最後設計一群組機器人團隊，包含三架輪型機器人，皆具備超音波、電子羅盤與無線感測網路，在實驗室設定的情境範例中偵查環境、合作巡邏。Robots help human beings undertake various duties in complicated environment. Even though GPS has succeeded in providing city maps, Robot still need to get the information of inner spaces compartment and locations of unknown obstacles, and then construct the path planning of the field. so the space plan can be drawn. However, In comparison with single robot, Multi-robot can perform better efficiency and raise higher Fault law as they cooperate through radio traffic. Thus, for a Multi-robot system, how the mission can be fluently achieved depends on the quality of communication. In other words, every single robot under the system should always work with up-standard communication quality.

In this essay, we use ZigBee(WSN) to apply the module of Received Signal Strength Indicator (RSSI) and the connect to avoidance mechanism, in order to maintain the exact distance within their mission as the group can reform their positions as the each unique barriers are precisely sensed in the environment. In this experiment, the multi-robot system is previously computer analogized before the data are calculated so that the pathways for each robot can be planned out. Finally a multi-robot group is designed with three sets of robot, all of which are assembled with Ultrasonic Sensors, e-compasses and wireless sensor devises. The system has been proved successful in this essay with the fact of the achievement of robots’ reconnaissance and patrol in a lab-settled module environment.