# Real-Time Navigation for Autonomous Surface Vehicles In Ice-Covered Waters

## TL;DR

This paper introduces a real-time navigation framework for autonomous surface vehicles operating in ice-covered waters, focusing on collision avoidance and efficient routing through a lattice-based planner with a novel cost heuristic.

## Contribution

It presents a new real-time, receding horizon navigation method with a specialized cost function and heuristic for ice interaction, applicable even without a fixed goal.

## Key findings

- Effective in high ice concentration environments
- Validated through simulated and real-world experiments
- Reduces collision risk and travel distance

## Abstract

Vessel transit in ice-covered waters poses unique challenges in safe and efficient motion planning. When the concentration of ice is high, it may not be possible to find collision-free trajectories. Instead, ice can be pushed out of the way if it is small or if contact occurs near the edge of the ice. In this work, we propose a real-time navigation framework that minimizes collisions with ice and distance travelled by the vessel. We exploit a lattice-based planner with a cost that captures the ship interaction with ice. To address the dynamic nature of the environment, we plan motion in a receding horizon manner based on updated vessel and ice state information. Further, we present a novel planning heuristic for evaluating the cost-to-go, which is applicable to navigation in a channel without a fixed goal location. The performance of our planner is evaluated across several levels of ice concentration both in simulated and in real-world experiments.