Evaluation of the NPS PHOENIX autonomous underwater vehicle hybrid control system

Abstract

This paper describes recent work with the NPS PHOENIX vehicle in the further development of the intelligent control software incorporating hover control behaviors. Of particular interest is the use of the TRITECH ST1000 and ST725 high frequency sonars to provide data about the environment. Vehicle positioning is proposed to be based in a local relative sense, augmenting global positioning by LBL transponders. Motion behaviors around a target area have been implemented including: diving and pitch control under thruster power; heading control at zero speed; lateral and longitudinal positioning; and the automatic initiation of filters as needed for target tracking. A tri-level controller architecture is discussed as part of an ongoing evaluation for coordinating the task based control of vehicle robotic behaviors.