A Propelled AUV Simulator: A Case of Integration Between Gazebo Harmonic and ROS 2 Iron

The simulation of underwater vehicles provides a detailed view of their behavior, allowing us to validate their physical and hydrodynamic design, test control algorithms, and correct errors before implementation. This paper presents the methodology for the simulation of an autonomous underwater vehicle (AUV), named AIAPAEC, propelled by four thrusters, running on Gazebo Harmonic and ROS 2 Iron. Gazebo Harmonic simulates the three-dimensional behavior of the AUV using hydrodynamics, buoyancy, and thruster plugins, which replicate the AUV dynamics in an aquatic environment. In addition, the simulator provides the attitude, position, and velocities of the vehicle, based on the inertial measurement unit plugin, the odometry plugin, and the doppler velocity log plugin. The integration with ROS 2 Iron through ROS Gazebo Bridge allows the implementation of open-loop and closed-loop maneuvers. Five simulations are presented to verify simulator performance, validate control algorithms, and analyze the relationship between simulator frequency and Real Time Factor (RTF). The tests used an odometry sensor at 100 Hz, and IMU and DVL sensors at 10 Hz. The Gazebo base frequency was set to 1000 Hz and 100 Hz. Results from the on-off and MIMO controllers showed a good fit with the temporal responses. Finally, a performance comparison of the MIMO control simulation, with harmonic settings in Gazebo at 1000 Hz and 100 Hz, evaluated the impact on RTF using sensor sampling frequencies of 10 Hz for IMU and DVL, and 100 Hz for odometry.