Short-Term Drifter Position Estimation Based on Ship-Generated Waves for Search and Rescue

Accurately estimating the initial drifter position in man overboard incidents within the first few minutes after a maritime accident is critical for improving search and rescue efficiency. However, the conventional Leeway model, which estimates drift trajectories based mainly on wind and ocean currents, fails to incorporate wave effects generated by ships. As a result, it can lead to significant positional errors in ship-related overboard accidents. This study proposes an improved drift estimation model that integrates ship-induced surface velocities into the Leeway model. The ship-generated wave field was modeled using the Kelvin model, and the induced speed calculated based on this was reflected in the drift estimation process. Numerical simulations were conducted across various ship scales and speeds to evaluate the effectiveness of the proposed model. The simulation results demonstrate that, under identical ship speeds, larger ships generate stronger lateral drift displacements, while longitudinal displacements tend to decrease depending on the conditions. These findings confirm that accounting for ship-induced wave effects can significantly enhance the short-term accuracy of drifter position estimations.