Path Tracking Control Method of Underwater Glider Based on Heading Compensation

This paper focuses on the problem of horizontal path tracking control for underwater glider under internal model nonlinearity and external environment disturbances. A dynamic model of underwater glider Petrel-II 200 is established as the simulation platform of closed-loop control system, and a path tracking control method including integral light-of-sight(ILOS), sliding mode control(SMC) with heading compensation(HC), and particle filter(PF) is proposed. The desired heading angle of the underwater glider is updated in real time by the ILOS algorithm. The SMC algorithm based on HC is used to eliminate the steady state error in the heading control. The PF is introduced into the feedback loop to reduce the interference of process noise and measurement noise. The complete path tracking control model is verified by numerical simulation. According to the numerical simulation results, the proposed method reduces the mean heading error and the root mean square error in square wave heading tracking by 80.14% and 4.1%, respectively, compared with the traditional proportional-integral-derivative(PID) control. Also, the maximum heading error and the standard deviation in sinusoidal heading are reduced by 40.9% and 3.6%, respectively. The high frequency oscillation of the rudder angle output is also avoided, which effectively reduces the energy consumption. In the filtering simulation, PF can filter out 80% of fixed heading noise and 90% of random heading noise, and in the path tracking simulation, the proposed method can effectively track the desired path. These numerical simulation results verify the effectiveness of the proposed path tracking control method.