Ship Path Planning using Navigational Charts with Time-Dependent Weather Constraints

Abstract

Automatically planning safe paths for ships to follow will be an important step towards a more autonomous shipping industry. This thesis develops an algorithm that generates safe paths that avoid grounding, sailing in dangerous weather conditions, and sailing against the dictated flow of traffic. The algorithm uses the NAVTOR API to extract data from navigational charts, and uses this chart data to find a path that avoids grounding and violating traffic separation schemes. A continuous state bidirectional A* algorithm that takes the kinematic constraints of the ship into account is implemented and tested in multiple situations on official navigational charts. The search algorithm is developed further to handle bidirectional search with time-dependent constraints. This is used to generate a path that avoids sailing in dangerous weather which changes throughout the voyage. The algorithm will either wait out the weather at the initial port, or find a route that circumvents the dangerous area. The resulting algorithm generates safe paths with respect to grounding and weather constraints, and manages to follow the traffic routing schemes when they are implemented in a consistent manner. Further work is required to handle cases where the traffic routing schemes cannot be interpreted literally. Some changes to the way navigational charts are designed are outlined which would make this process easier.