STRATEGIES FOR SIMULTANEOUS MULTIPLE AUTONOMOUS UNDERWATER VEHICLE OPERATION AND CONTROL

Undersampling of the coastal oceans remains a persistent problem for s tandard oceanographic measurement practice wherein an instrument packa ge is tethered to a research vessel. The overhead costs associated,wit h operating a large research vessel impose a strict minimum on the cos t of data collected Owing to the overheads, significant improvements i n sampling technology on the tethered platform can only produce modest gains in the cost effectiveness. In contrast, untethered vehicles if operated simultaneously! have the potential to increase cost effective ness significantly by distributing the overhead costs over several sam pling platforms. Furthermore, synoptic and pseudosynoptic data can be collected with multiple autonomous underwater vehicles (AUVs), thereby providing the type of information critical to dynamic process modelin g unattainable with non-synoptic data. While the goal of simultaneous multiple-vehicle operation has been espoused over the last few years, A UV technology and practice have until recently beer? too immature to realize that potential. Recently, Florida Atlantic University (FAU) h as developed a new series of modular AUT's with the express purpose of supporting multiple sensors and multiple-vehicle operation. This seri es of vehicle is called the Ocean Explorer of which three have been pr oduced so far. This paper will explore some of the associated navigati on, tracking, control and deployment problems associated with multiple -vehicle operation in coastal applications. In addition, the character istics of the component level intelligent distributed control system, integrated data logger and vehicle control system will be discussed. I II particular this paper will discuss how FAU has applied the concepts of elastic constraint propagation and the symmetric fuzzy decision-ma king model to AUV control systems. Some results of early experiments i n synoptic data collection with a conductivity, temperature and depth (CTD) sensor using multiple AUVs for the determination of horizontal s tructure will be described.