A boats coxswain is adept at analyzing the wave environment, adjusting the crafts propulsion system and control surfaces to mitigate its motions and reduce the chance of capsizing. There is a significant predictive component in the coxswains control decisions. Unmanned surface vehicles (USVs) lack the benefit of a highly trained coxswain reading and predicting oncoming waves - existing autonomous control systems are not aware of the wavefield, nor are they capable of combining near and far wave field information with current information about the craft in order to make adjustments to the propulsion system and control surfaces. This makes the USV susceptible to excessive shocks and motions, which may degrade mission performance, or capsizing. The proposed effort will develop a motion mitigation system including wave sensing and characterization, USV motion prediction, and vessel control for USVs. The system builds upon successful past and current research and development in using wave sensing data, advanced hydrodynamics for wave field reconstruction and vessel dynamics, and vessel control systems in improving steering and motion control of USVs in high sea states.
Benefit: The anticipated benefits of the proposed research and development are substantial improvements in the ability of an unmanned surface vessel (USV) to operate in high sea-state environments, thereby increasing the operating envelope of the USV. The commercial applications for the proposed system are in the area of unmanned surface vessels (USVs) that serve both military and non-military purposes. Additionally, the technology that will be developed has direct application to manned craft.
Keywords: motion control, motion control, Propulsion Control, USV, Wave sensing, wave field reconstruction, wave field prediction
