Pitch Angle Control with Model Compensation Based on Active Disturbance Rejection Controller for Underwater Gliders

Guo, T.; Song, D.; Li, K.; Li, C., and Yang, H., 2020. Pitch angle control with model compensation based on active disturbance rejection controller for underwater gliders. Journal of Coastal Research, 36(2), 424–433. Coconut Creek (Florida), ISSN 0749-0208.As the pitch angle control system of an underwater glider is nonlinear, multivariate, and has strong coupling, active disturbance rejection control (ADRC) was applied in the pitch angle control loop. To improve the control precision and responsiveness, a model compensation (MC) was presented to alleviate the estimation pressures for the extended state observer in the ADRC. The vast majority of parameters in the MC were estimated and identified so that the ADRC controller can work better. Simulation experiments illustrated that the MC based on ADRC was effective. For the pitch angle control, the overshoot was reduced by 4.5% and the settling time dropped to 90 seconds compared with the traditional ADRC. It demonstrated a more accurate motion trajectory control effect for an underwater glider. Besides, the MC-ADRC controller has better dynamic characteristics and antidisturbance ability, which ensure that the underwater glider is more anti-interference and flexible.