Simulations for Autonomous Water Surface Vehicle

Hi! Currently I'm working for on a project on an autonomous water surface vehicle for survey purposes. My major part will be to understand and model the controller for path planning, and obstacle avoidance. I need some help in designing the complete software for the tasks and some guidance to make a prototype later which I can look after it once I get an idea about the complete system software. I'm looking for someone who can help me in designing the autonomous navigation system and obstacle avoidance system while performing some simulations in any virtual environment for having a basic idea of how the ASV performs in real world conditions.