Five-Tiered Route Planner for Multi-AUV Accessing Fixed Nodes in Uncertain Ocean Environments

TL;DR

This paper presents a comprehensive five-tiered route planning framework for multiple AUVs operating in uncertain ocean environments, improving efficiency and coordination in multi-node access tasks.

Contribution

It introduces a novel multi-tiered route planner that integrates pre-planning, route planning, path tracking, and online coordination for AUV fleets in stochastic conditions.

Findings

Reduces AUV usage by 7.5% compared to existing methods.

Improves task completion rate by 6.2% with the same number of AUVs.

Demonstrates effectiveness through multiple simulation scenarios.

Abstract

This article introduces a five-tiered route planner for accessing multiple nodes with multiple autonomous underwater vehicles (AUVs) that enables efficient task completion in stochastic ocean environments. First, the pre-planning tier solves the single-AUV routing problem to find the optimal giant route (GR), estimates the number of required AUVs based on GR segmentation, and allocates nodes for each AUV to access. Second, the route planning tier plans individual routes for each AUV. During navigation, the path planning tier provides each AUV with physical paths between any two points, while the actuation tier is responsible for path tracking and obstacle avoidance. Finally, in the stochastic ocean environment, deviations from the initial plan may occur, thus, an auction-based coordination tier drives online task coordination among AUVs in a distributed manner. Simulation experiments are conducted in multiple different scenarios to test the performance of the proposed planner, and the promising results show that the proposed method reduces AUV usage by 7.5% compared with the existing methods. When using the same number of AUVs, the fleet equipped with the proposed planner achieves a 6.2% improvement in average task completion rate.