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.

翻译：船舶在冰覆盖水域中的通行对安全高效的运动规划提出了独特挑战。当冰的浓度较高时，可能无法找到无碰撞轨迹。相反，若冰层较小或接触发生在冰层边缘附近，则可将其推开。本研究提出一种实时导航框架，能够最小化与冰的碰撞次数及船舶航行距离。我们采用基于网格格的规划器，其代价函数捕捉了船舶与冰的相互作用。为应对环境的动态特性，我们基于更新的船舶与冰状态信息，以滚动时域方式进行运动规划。此外，我们提出一种用于评估剩余代价的新型规划启发式方法，适用于无固定目标点的航道导航。在仿真与真实实验中，我们评估了该规划器在不同冰浓度级别下的性能。