Supervisor:
Southwest Ordnance Industry Bureau
Organizer:
Chongqing Ordnance Industry Society
Chongqing University of Technology
Chongqing University of Technology
Research on control of ship dynamic positioning system based on novel TSM
| DOI: | 10.11809/bqzbgcxb2024.11.005 |
| Keywords: | dynamic positioning system; fixed time; non singular fast terminal sliding mode; extended state observer; input saturation |
| Abstract: | In complex ocean conditions, ship dynamic positioning systems often experience challenges such as low positioning accuracy and slow convergence speed, which hinder effective path tracking through controller design.To enhance the convergence speed and control accuracy of the dynamic positioning system, this study proposes a novel fixed time stable non singular fast terminal sliding mode control strategy.By incorporating a constantly changing function term into the original fixed time stability method, the convergence speed is improved, and a detailed proof process is provided.The proposed method utilizes a novel fixed time stabilization algorithm to determine an upper bound on the convergence time.This upper bound depends on the system parameters and remains independent of the system’s initial state.Moreover, a fixed time extended state observer is employed to estimate the ship’s sailing speed and the ocean disturbance force accurately.Additionally, a fixed time non singular fast terminal sliding mode output feedback controller is introduced, replacing the sign function with a saturation function.This modification effectively addresses singular value issues and reduces chattering phenomenon.The proposed controller achieves fixed time convergence of the tracking error, with the convergence time being pre settable.Furthermore, the proposed method assists the dynamic system in compensating for the force and torque output saturation by the controller, thus reducing faults caused by high speed rotation of the propeller.Experimental results demonstratethis method can effectively improve the control accuracy and convergence speed of the system.These findings effectively enhance the control accuracy and response speed of the system, offering valuable insights for future research in ship dynamic positioning system. |
| Published: | 2024-11-30 |