Research Of AUV Motion Control In Vertical Plan Based On ADRC

The intelligent motion control technology of Autonomous Underwater Vehicle (AUV) is the basis of long-distance voyage for AUV. The motion control capability in vertical plane is an important technical for AUV to complete multifarious missions. So, it is important and realistic significance to research on motion control in vertical plane of AUV.Motion control problem of AUV in vertical plane, especially depth and pitch control problems are researched in-depth based on active disturbance rejection control (ADRC) method in this paper. It is aiming to solve the vertical movement control interferential problems of AUV in ocean environment.Firstly, the mathematical model of the vertical movement of AUV is improved and the maneuverability of the model is simulated. Considering the maneuverability of thrusters and elevator, internal and external disturbances of model uncertainty, currents, waves and transmission signal interference etc, the vertical motion model of AUV is improved. Vertical maneuverability of AUV is simulated using the improved model. Some valuable maneuverability parameters both in theory and in practice are obtained by simulation.Secondly, based on the ADRC theory, the vertical ADRC controller of AUV is designed and realized, and its performance of immunity is analyzed. According to typical interference and outside disturbance such as model uncertainty, currents, waves, the transmission signal interference, the disturbance rejection performance of ADRC is analyzed, and its parameter adjusting law is summarized. ADRC coordinated control method of pitch and depth is mentioned to solve the large depth change and large pitch problems during AUV vertical movement. Depth and pitch ADRC controllers and their coordinated controller of underactuated AUV in vertical plane are designed respectively.Finally, the vertical motion control simulation experiments were carried out by hard-ware-in-loop simulation system to validate the disturbance rejection performance of the designed ADRC controller of AUV further. Control effect and disturbance rejection performance of vertical controller for AUV are verified by typical scenarios such as successive dive to a large depth, sawtooth tracking in vertical plane and sailing as a fix height. The interference factors and the quality of navigation control are analyzed when AUV navigate near and under surface in sea trials. More, single control and coordinated control of pitch and depth are both simulated based on the sea trial data. The results show that the ADRC method can realize vertical navigation mobility of underactuated AUV and reduce possible danger for large depth change and large pitch during vertical movement.The vertical ADRC controller of AUV designed in this paper can effectively restrain the internal and external disturbances such as model uncertainty, currents, waves, transmission signal interference. Its control effect satisfies project requirements and improves immunity and robustness of AUV. The research achievements are of important reference value for applying the ADRC method to practical engineering and improving the vertical motion control effect of AUV.