An analysis method and a compensation strategy of motion accuracy for underwater glider considering uncertain current

Abstract Currents may make underwater glider deviate from desirable motion trajectory seriously, which will obstruct the smooth progress of underwater exploration mission. This paper attempts to study an analysis method and a compensation strategy of the glider motion accuracy, considering uncertain current. First, the dynamic model of an underwater glider is established, and the model is validated by experimental data measured in the South China Sea. Next, we present an evaluation parameter of the glider motion accuracy. Then the motion accuracy of the glider with different control parameters values is quantitatively analyzed by Monte Carlo method when the uncertainty of current is considered. The uncertain parameters of current include position, direction, intensity and action depth. In addition, to reconcile simulation accuracy with efficiency, we install a stopping rule for Monte Carlo simulation (MCS), based on the relative error of mean estimation. Then, to improve the glider motion accuracy in uncertain current, a feedback control strategy that intermittently corrects the yaw angle is proposed. Finally, we verify the validity of the feedback control strategy and analyze its applicable situation by MCS. The research results can provide certain guidance for the realization of the glider precision operation.