Bearing Stabilization and Tracking for an AUV with an Acoustic Line Array

Passive underwater detection and tracking sonar systems using autonomous underwater vehicles (AUVs) have many important applications. Because of imperfections in vehicle control, it is common for an AUV to undergo significant yaw and pitch oscillations. As a result, it is important to compensate for the vehicle motion when generating true bearing estimates while using a rigidly attached acoustic line array. This paper describes full beam interpolation tracker and bearing stabilization algorithms that were implemented to address these issues on an intelligent AUV sonar sensor and tested during a subsequent sea trial with the goal of providing target bearing estimates to a target track estimation algorithm. These beam tracking and bearing stabilization algorithms can also be applied to the case of a flexible towed array with some additional modifications. Initial results indicate that this is an effective method of measuring stabilized true target bearings