Route optimizing and following for autonomous underwater vehicle ladder surveys

Yanqing Jiang,Ye Li,Ziye Zhou,Teng Ma,Jiayu He,Li An,Yumin Su

doi:10.1177/1729881418813271

Abstract

An autonomous underwater vehicle is able to conduct coverage detections, such as sea terrain mapping and submerged objects detection, using sonar. This work addresses the task of both optimizing and following routes that present a ladder shape. First, a planning method to determine a nearly optimal coverage route is designed. The track spacing is optimized considering the seabed type and the sonar range for the purpose of increasing detection probability. It also adds adaptability to confined water, such as harbors, by decomposing the geometrically concave mission region during the processing of the environmental data. Next, a decoupled and two-layered structure is adopted to design the following controller. The route is followed in the form of sequenced-lines tracking. A proportion–integral–derivative algorithm with fuzzy parameters adjustment is employed to calculate a reference heading angle according to the transverse position deviation in designing the guidance controller. An adaptive nonlinear S-surface law is adopted to design the yaw control. The route following the method is demonstrated with sonar (including side scanning sonar and multi-beam echo sounder) imagery collected in terrain mapping and object detection through sea trials.

Highlights

Nowadays, littoral coastal waters are playing an increasingly important role as are the interactions between humans and the sea
Littoral coastal waters are playing an increasingly important role as are the interactions between humans and the sea. These waters are involved in business and military applications, such as archaeology of the continental shelf, seabed terrain mapping, coral reef surveys, sunken ship location, and sea mine detection
A preprogrammed strategy such as turning to a certain heading angle is mostly used in the face of Science and Technology on Underwater Vehicle Laboratory, College of Shipbuilding Engineering, Harbin Engineering University, Harbin, China

Summary

Introduction

Littoral coastal waters are playing an increasingly important role as are the interactions between humans and the sea. These waters are involved in business and military applications, such as archaeology of the continental shelf, seabed terrain mapping, coral reef surveys, sunken ship location, and sea mine detection. All the abovementioned applications refer to the coverage activity. The survey pattern of a coverage mission includes a ladder or a lawn mower pattern, an internal spiral pattern, and a random pattern. The random pattern does not ensure either full or a specific percentage of coverage. It is usually used to do something easy and less significant such as floor sweeping. A preprogrammed strategy such as turning to a certain heading angle is mostly used in the face of Science and Technology on Underwater Vehicle Laboratory, College of Shipbuilding Engineering, Harbin Engineering University, Harbin, China

Objectives

Conclusion