Control of Longitudinal Motion for Under Water High Speed Supercavitating Vehicles

For the control design of the high-speed supercavitating vehicles, the $H_{\infty}$ control is proposed and this $H_{\infty}$ performance requirement is analyzed in the paper. The $H_{\infty}$ performance requirement lead to the problem of selection of weights on the state variables and control inputs. A comprehensive solution to this weight selection problem is presented. And the unit weighting $H_{\infty}$ control was comparisoned in the paper. Simulation shows general unit weighting coefficient design of $H_{\infty}$ control doesn't work in this special problem. This $H_{\infty}$ design methodology can also be used for other $H_{\infty}$ problem as well.