Development of a Three-Dimensional Simulator for Integrated Testing of Path-Planners and Controllers for Autonomous Underwater Vehicles

Autonomous underwater vehicles (AUVs) operating in deep sea and littoral environments have diverse applications ranging from marine biology exploration and search for plane crash sites to ship-hull inspection and border patrol. This paper reports on the development of a modeling and simulation platform that supports the design and testing of path planning and control algorithms in a synthetic AUV, representing a simulated version of a physical AUV. The dynamical behavior of the AUV is modeled using the equations of motion that incorporate the effects of external forces (e.g., buoyancy, gravity, hydrodynamic drag, centripetal force, Coriolis force, etc.), thrust forces, and inertial forces acting on the AUV. The equations of motion are translated into a state space formulation and the S-function feature of the Simulink and MATLAB scripts are used to evolve the state trajectories from initial conditions. Experimental validation is carried out by performing integrated waypoint planner (using the A* algorithm) and PD controller implementations that allow the synthetic AUV to track dynamically feasible trajectories in two- and three- dimensional spaces. An underwater pipe-line inspection task carried out by the AUV is demonstrated in a simulated environment.