Position Estimation Methods for Powerless Ocean Surface Vessels

Abstract

In this paper a position estimation method for precisely tracing the trajectory of ocean surface vessels under the situation of powerless and losing communication ability via the aid of the ocean current solution and nonlinear estimation method is proposed The method procedure and contributions for the estimation is addressed as follows: First a group of momentum equations which is not easy to find the exact solution because of its complexity is proposed for ocean current modeling The solution of these equations will be accurately solved by one new derived fuzzy approximation technology via a set of practical current observed data around Taiwan The main contribution of this new modeling method can offer researchers one more useful and accurate ocean current history Second a model formulated in state-space form for describing the drifting behavior of monitored ocean surface vessels is identified according to analysis the drifting behavior in practical situation from mechanical viewpoint Third based on the above solution of ocean current and the identified model described the drifting behavior of monitored ocean surface vessel a position estimation method realized with Extend Kalman filter are developed for the powerless drifting vessels which are driven by the ocean current is investigated The simulation errors are 4 5±3% kilometers and 0 07±30% kilometers which simulate via real incidents for two days and two hours respectively and discussing the accuracy of drift estimation via using the different ocean data of different months

Date of Award	2014 Aug 27
Original language	English
Supervisor	Yung-Yu Chen (Supervisor)