Real-time Path Planning for Unmanned Surface Vehicle by Using Finite Angle A* Algorithm

• Main Authors: Chia-ChunFan, 范家郡
• Other Authors: Joe-Ming Yang
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/61966140450676755188

碩士 === 國立成功大學 === 系統及船舶機電工程學系碩博士班 === 101 === Recently, technological developments for autonomous surface vehicles (ASV) are advancing, where great focus is placed on lowering the cost and fabrication time. Hence, shortest path planning for unmanned surface vehicle (USV) is currently being investigated extensively. In this investigation, an improvement for the Real-time Finite Angle Astar (FAA*) method is proposed to improve the shortcoming of FAA* mentioned in previous studies. The proposed method enables the USV’s to instantaneously re-plot and re-route based on obstacles discovered en-route, ensuring the safest and shortest route to its programmed destination. Image analysis is utilized to convert color satellite images into binary images which are used as navigation maps in Real-time FAA*. The output paths planned by Real-time FAA* are dependent on the world geodetic system, which is the same as what satellites are based on, and these paths can be directly used by USVs with a GPS navigation system. In this article, fuzzy logic navigation is addressed and analyzed. The fuzzy controller of USVs is designed to automatically control two DC brush thrusters. The input variables of the fuzzy controller are provided by the GPS module and the electrical compass, and the output variables are used by the Pulse Width Modulation (PWM) technique to control power for the DC thrusters.