Autonomous Control of a Prototype Solar-powered Offshore AUV Servicing Platform

Abstract

This paper describes the implementation of a low-cost autonomous control system on the Platform for Expanding AUV exploRation to Longer ranges (PEARL). PEARL is a floating, solar-powered autonomous platform designed to function as a servicing station for Autonomous Underwater Vehicles (AUVs). The control architecture consists of off-the-shelf hardware components, built around an embedded Raspberry Pi microcomputer and Arduino microcontroller. An Inertial Measurement Unit (IMU) and GPS receiver provide navigation information, and real-time energy system statistics are monitored through a solar charge controller. The open-source MOOS-IvP marine robotics software is used to integrate these devices and achieve autonomous operations, consisting of station-keeping and waypoint missions. Results from tests demonstrating these missions, conducted during a recent field deployment at Deep Pond in Orleans, MA, are presented and discussed, including an RMS error of 0.9-2.2 meters achieved for waypoint pattern execution under realistic conditions, and an average battery charge depletion of13 percent per hour. This research helps pave the way for autonomous solar-powered service stations in the ocean helping to connect the underwater world with space.