Acoustic motion estimation and control for autonomous underwater vehicles.

Abstract

An integrated model of acoustic motion estimation and control is presented. The control system is designed on the basis of the definitions of suitable Lyapunov functions for the different maneuvers in approaching a target. These functions allow the navigation and maneuvering tasks to be performed in a two-layered hierarchical architecture for closed-loop control. The motion estimation algorithm uses pencil beam profiling sonar range and bearing information. The operating environment is modeled with a suitable three- dimensional potential function and its gradient which forms an attractive field. This algorithm provides satisfactory performance for autonomous navigation and obstacle avoidance. The applicability and robustness of this model are demonstrated with both actual test data obtained with the NPS Phoenix submersible and computer generated simulation data. The results show the effectiveness of the combined estimation and control model.