Numerical simulation and hydrodynamic analysis of an amphibious spherical robot

Considering that the necessity of amphibious operation in harsh environment, this paper firstly presents the structure of an amphibious spherical robot based on 3D printing technology, which can act as a carrier of reconnaissance equipment, weapons systems and communications systems, and perform a variety of tasks near the sea and beaches. Since the structure of the robot had features of amphibious characteristics and quadruped gaits. Inevitably, there are new problems in the process of kinetic mechanism analysis. It is hydrodynamic characteristic that is a critical factor for underwater robot. This paper presents the investigation of hydrodynamic performance of concept structure design of an amphibious spherical robot based on 3D printing technology with three basic motion-horizontal forward motion, ascending motion and sinking down motion in vertical plane. Firstly, the structural configuration, principle of work and performance parameter of the amphibious spherical robot based on 3D printing technology were described. Then the ANSYS WORKBENCH software was employed to establish the 3D model and meshing result of the amphibious spherical robot as well as its flow fields. For the reason that the complex structure of our amphibious spherical robot based on 3D printing technology will cause some limitations on hydrodynamic analysis, its 3D models was properly simplified and ANSYS FLUENT software was then used to analyze the impact of hydrodynamic factors according its three motion models, and compared the simulation results with the theoretical values. Finally, the pressure contours, velocity vectors and drag coefficient showed the detail of the flow field when the amphibious spherical robot is performing its three basic motion.