Development of Autonomous Surface Vessels for Hydrographic Survey Applications

Autonomously navigating surface vessels have a variety of potential applications for ocean mapping. The use of small vessels for coastal mapping is investigated through the development of hardware and software that form a complete system for survey operations. The hardware is selected to minimize cost while providing flexibility for installation on different platforms. MOOS-IvP open-source autonomy software enables independent operation of the vessel and provides for human monitoring. Custom applications allow the sensors and actuators of the hardware platforms to interface with MOOS-IvP. An autonomy behavior is developed that replicates current human driven survey acquisition, in which the boat plans paths automatically to achieve full survey coverage with a swath sonar system. With initial input of a survey boundary and depths from the onboard sonar system, subsequent paths are planned to be offset based on the collected data. This behavior is tested in simulation and field experiments. A model reference adaptive control system for the heading of the vessel is investigated for improved reliability of vessel operation in a variety of conditions and over the full range of operation speeds. Simulations tests verify the adaptation of two types of controllers. A new method for speed control to increase endurance and decrease engine wear is also proposed and simulated. Together, these developments form an easily configurable system that provides automated hydrographic survey capability to a vessel with minimal human involvement for optimal performance