Hydrodynamic Force Decoupling Using a Distributed Sensory System

Abstract

In this letter, we present a distributed pressure sensory system, inspired by the lateral line found in fish, for estimating hydrodynamic forces acting on an autonomous underwater vehicle. By canceling these forces using the vehicle control system, the dynamics of the vehicle can be decoupled from the state of the surrounding fluid. We discuss a control scheme which combines the measured hydrodynamic forces with a feedback controller that is robust to disturbances and measurement errors, achieving asymptotic tracking in the presence of bounded disturbances and errors. We compare this robust lateral line controller to a baseline robust controller not using the lateral line system and to a controller using the lateral line with simple PD feedback. We simulate a spatially and time varying velocity flow field on the scale of the vehicle and show that the robust lateral line controller has improved performance compared to both the baseline robust controller and the PD controller using the lateral line system.