Unmanned Underwater Vehicle Attitude Variable Structure Control Technology Research

With the rapid development of Unmanned Underwater Vehicle (UUV)’s manufacture craft, traditional design approaches in controller fail to meet engineering demands completely. Therefore, a new intelligent controller should be studied to meet various control demands of UUV. Variable Structure Control(VSC), indeed produce strong robustness and outstanding control results, which is suitable for no-linear and time-varying system in the dissertation. On this basis, we will focus on attitude control of UUV, which will be conducted based on VSC theory. The central contents as follows:1. Optimize PID controller: To compare sufficiently control effect of traditional controller with VSC controller, and resolve the optimization problem of control parameters in the practical engineering for applications, I have applied genetic algorithms(GA) and particle swarm optimization (PSO) to optimize traditional controller, respectively. And simulation example studies show this method is available.2. Improvement motility and accuracy of UUV:Selecting optimal PID and VSC as controller of the system, they respectively work on the attitude control of UUV. The availability and advantage of VSC proposed in the dissertation has been verified though simulation analysis and a great many comparisons among dynamic data.3. Stability of control system of UUV:To ensure the operation of controller steadily and efficiently, I have proposed a online stability criterion based on Lyapunov stability analysis method. Simulation studies show:when the strong interference effect of system parameters changes and external noise applied to the systems, VSC quality is still good;the stability criterion not only guarantees the limitation of output, but achieves sound motility and stability due to control module of stability supervision and control.In order to solve some drawbacks of UUV’s controller in dynamic property, the paper has proposed a solution based on VSC theory, which improves dramatically performance of control system.The proposed method for stability analysis carries sound supervise and control results, and it is of important value for engineering applications.