Design and control of an high maneuverability remotely operated vehicle with multi-degree of freedom thrusters

Abstract

This research involves the design, manufacture, and testing of a small, < lm³, < 1Okg, low cost, unmanned submersible. High maneuverability in the ROV as achieved through a high thrust-to- mass ratio in all directions. One identified solution is moving the primary thrusters in both the pitch and yaw directions. The robot is propelled by a pair of 2 DOF thrusters, and is directly controlled in heave, surge, sway, yaw, and roll. Pitch is controlled through passive buoyancy and, potentially, active manipulation of added mass and gyroscopic effects. This system is compared against a traditional fixed-thruster system in terms of cost, size, weight, and high/low speed performance. Preliminary results indicate that the actuated system can provide an improved thrust-to-mass metric at the expense of increased system complexity. This margin of improvement increases with increasing thruster size. The system has applications in high accuracy positioning areas such as ship hull inspection, recovery, and exploration.