Performance Evaluation of a Hybrid Thruster for Spherical Underwater Robots

In this article, a hybrid thruster for spherical underwater robots (SURs) was developed and its performance was evaluated. The objective of this work was to improve the execution efficiency, multimodality, and maneuverability of the autonomous underwater robot (AUV). First, using meshing method, the open-water performance and flow field of individual water-jet and propeller thruster were analyzed. Numerical simulations were calculated and verified using experimental data. Then, the interaction between the hybrid thrusters was discussed, and the flow field characteristics and hydrodynamic performance of the hybrid propulsion system were validated through streamline and pressure distribution. Finally, the hybrid propulsion system was designed; the thrust measurement experiments and the basic motion experiments for SUR using a hybrid thruster were carried out, including water-jet mode, propeller mode, and hybrid mode. The experimental results further verified the performance of the hybrid propulsion system, which meet the requirements of rapidity and flexibility, as well as the feasibility of underwater applications.