Distance keeping for underwater vehicles - tuning Kalman filters using self-oscillations

This paper describes the use of Kalman filtering in distance keeping for underwater vehicles. The vision-based distance keeping module has been mounted on a micro-ROV equipped with a camera. Distance from a plane-like obstacle is determined on the basis of the laser dot projections within the frame. Since these measurements are not reliable a Kalman filter is designed - unknown dynamic model parameters are determined using the self-oscillation experiments which prove to be simple and time preserving. Finally, an I-PD controller is designed based on the Kalman filter estimates. The main task of the controller is to keep the vehicle perpendicular to the surface at a desired distance.