Underwater Positioning Using Near Surface Long Baseline Transponder’s Induced by Wave Motion

Abstract

This paper presents a filter for underwater positioning in an aquaculture environment with demanding weather conditions. The positioning system is based on acoustic transponders mounted at a net pen on the sea surface. The transponders are exposed to oscillations due to wave disturbance. This will have an impact on the accuracy of the positioning system. An extended Kalman filter (EKF) solution has been proposed including a wave motion model integrated with the pseudo-range measurements from the transponders. Simulations show that the proposed filter compensates well for the disturbances.

Experimental verification of underwater positioning system in aquaculture

“…This effectively means that the filter converges. This paper presents an experimental verification of an EKF design building on [4]. Demanding weather conditions will impose oscillations on the transponders near the surface area.…”

“…The main contribution of this paper is the experimental verification of the work presented in [4], where an error model was suggested. This is an important contribution since it enables mounting of transponders near the ocean surface on aquaculture structures in harsh conditions, without more expensive solutions like calculating the transponder position with GNSS in real time.…”

“…This paper builds on the work presented in [4]. In the prvious work a filter with wave motion comensation was developed and verified by simulations.…”

“…This is an important contribution since it enables mounting of transponders near the ocean surface on aquaculture structures in harsh conditions, without more expensive solutions like calculating the transponder position with GNSS in real time. The work solves the challenge [4] of modeling the position estimate error. This error occurs because of the wave motion of the transponders.…”