Predictive Control of a Supercavitating Vehicle Based on Time-Delay Characteristics

Abstract

Supercavitation technology can greatly improve the speed of underwater vehicles by reducing drag. However, the time-delay characteristic of a supercavitating vehicle presents control challenge. In this paper, a linear parameter-varying (LPV) time-delay model for a supercavitating vehicle is established by analysing the time-delay characteristics of the planing force. Moreover, considering that the cavitation radius is easily perturbed by external disturbances, a supercavitating LPV delay model depicted as a polytope is established. Based on the model, a predictive controller based on time-delay characteristics is designed. The controller can solve linear matrix inequalities (LMI) online to find the optimal solution at a given moment. In addition, the controller introduces a different Lyapunov function and multiple free control variables to reduce the system's conservativeness and expand the system's initial feasible region, which can improve the control performance of the system. A simulation verifies that the system exhibits good stability and robustness.

Keywords

• LMI
• predictive controller
• planing force
• supercavitation
• time-delay characteristics