Depth Control System for Undersea Vehicles

This SBIR project proposes an optimal combination scheme of depth keeping control systems, winch employs "integrated and multi-level robust adaptive control technique to improve the depth keeping performance. The proposed concept consists of three-level' control reinforcement configuration. The first level employs the nonlinear control techniques tonately linearize and decouple the input-output dynamics of the system and to achieve the design requirements for nominal operating. The robust control, as a second level, is designed based on the linearized and decoupled system dynamics to guarantee the, performance in the presence of tainties. Finally, a novel adaptive control scheme is employed to provide adaptivity and to fine tune the hovering control system (HCS) performance. Ibis optimal combination scheme exploits and integrates the merits offered by nonlinear, robust and adaptive control and is expected, to greatly enhance the performance and increase the service life of future undsea vehicles. This multilevel scheme explicitly considers and incorporates model uncertainty and system nonlinearity during design process. Impacts of Parameter variation and flexible modes on the performance of hovering control systems will be used to assess, our proposed control concept during Phase I efforts.