COLREGs Compliant Collision Avoidance and Grounding Prevention for Autonomous Marine Navigation

2026-03-02

AI Summary

This work proposes a unified motion planning framework to address the real-time navigation challenge for autonomous vessels operating in complex waterways, where compliance with the International Regulations for Preventing Collisions at Sea (COLREGs), grounding avoidance, and dynamic feasibility must be simultaneously satisfied. The approach uniquely integrates directional COLREGs constraints, an extended velocity obstacle (VO) method that accounts for uncertainty in target vessel states, and a convex approximation of non-convex shallow-water regions derived from nautical chart bathymetry via integer linear programming (ILP). All safety constraints are jointly handled within a convex optimization framework. Simulation results demonstrate that the method generates COLREGs-compliant, dynamically feasible, and safe velocity commands in real time during multi-ship encounter scenarios, effectively balancing collision avoidance, grounding prevention, and navigational efficiency.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Intelligent Robots: Motion and Path Planning
• Constraint Satisfaction and Optimization: Constraint Optimization

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Applied ML and AI for Web-based mobile applications
• Responsible Web: Machine-in-the-loop, human agency and autonomy
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

Maritime Autonomous Surface Ships (MASS) are increasingly regarded as a promising solution to address crew shortages, improve navigational safety, and improve operational efficiency in the maritime industry. Nevertheless, the reliable deployment of MASS in real-world environments remains a significant challenge, particularly in congested waters where the majority of maritime accidents occur. This emphasizes the need for safe and regulation-aware motion planning strategies for MASS that are capable of operating under dynamic maritime conditions. This paper presents a unified motion planning method for MASS that achieves real time collision avoidance, compliance with International Regulations for Preventing Collisions at Sea (COLREGs), and grounding prevention. The proposed work introduces a convex optimization method that integrates velocity obstacle-based (VO) collision constraints, COLREGs-based directional constraints, and bathymetry-based grounding constraints to generate computationally efficient, rule-compliant optimal velocity selection. To enhance robustness, the classical VO method is extended to consider uncertainty in the position and velocity estimates of the target vessel. Unnavigable shallow water regions obtained from bathymetric data, which are inherently nonconvex, are approximated via convex geometries using a integer linear programming (ILP), allowing grounding constraints to be incorporated into the motion planning. The resulting optimization generates optimal and dynamically feasible input velocities that meet collision avoidance, regulatory compliance, kinodynamic limits, and grounding prevention requirements. Simulation results involving multi-vessel encounters demonstrate the effectiveness of the proposed method in producing safe and regulation-compliant maneuvers, highlighting the suitability of the proposed approach for real time autonomous maritime navigation.

Problem

• COLREGs compliance
• collision avoidance
• grounding prevention
• autonomous marine navigation
• Maritime Autonomous Surface Ships

Innovation

• COLREGs compliance
• convex optimization
• velocity obstacles
• grounding prevention
• autonomous marine navigation