Trajectory-Based Synthesis of Propulsion Systems for Fixed-Thrusters AUVs

Abstract

This paper presents a synthesis method for the Autonomous Underwater Vehicle (AUV) propulsion system based on the features of a trajectory to follow. This method is based on solid/fluid dynamics analysis of a AUV performing the trajectory following task and gives actuation requirements to achieve it properly. This actuation is then used to generate a propulsion system under the form of a Thrust Configuration Matrix (TCM) that is compatible with the desired trajectory. From this matrix the number of thrusters, their position and direction can then be extracted to synthesis a fitted propulsion system. Thus, the propulsion capabilities of the robot will match the trajectory characteristics and it will be able to follow it. The objective of this work is to provide an evaluation as well as a design method to produce a controllable AUV for a given task. A second use of such an analysis is to provide an evaluation process allowing to perform AUV task-based design. The method is developed for generic fixed-thrusters AUVs on any trajectory, and is applied to an existing 4-thrusters AUV for a seabed scanning flat trajectory. The method shows why the initial AUV propulsion does not match the task and what is the solution solving the issue.