Motion control method in conditions with low-speed AUV trans-current propelling and without output

Abstract

The invention proposes a motion control method in conditions with low-speed AUV trans-current propelling and without output. The method comprises the following steps: first, obtaining from a propeller open-water test the propelling force curve of the propeller to determine the rotation speed range of the propeller in conditions with output; then, using a fuzzy controller to seek the required rotation speed according to the heading deviation and the heading deviation rate wherein the required rotation speed is included in the rotation speed range obtained by the propeller open-water test; and finally, inputting the heading deviation and the heading deviation rate into a PID controller to seek the working time interval of the propeller for stable rotation speed. The propeller operates at the determined rotation speed at a given time interval to determine the speed, and drives the AUV to the target heading. Compared with the traditional control method considering the nonlinear constraints of a propeller, the method is convenient and efficient, and without the accurate modeling or approximate estimation of the nonlinear constraints of the propeller, a phase-step output controller determining the rotation speed of the propeller and its working time can be established directly from the accurate relationship between the rotation speed and the propelling force, therefore, increasing the response speed.

Description

technical field [0001] The invention relates to a method for controlling an underwater vehicle, in particular to a motion control method for an AUV under the condition of low speed and no output. Background technique [0002] With the deepening of ocean development, intelligent underwater vehicles (AUVs) are becoming more and more popular for their advantages of small size, flexible movement, and ability to operate autonomously. It has become an important tool for ocean development. In order for an underwater vehicle to reach a designated location and perform a specific task, it must be precisely controlled. In the actual control system, due to the limitation of the physical properties of the components, the actuator usually has a dead zone phenomenon, that is, the actuator has no output at low speed. In the AUV heading control, the phenomenon of no output at low speed is more obvious. And with the change of working conditions and environment in the production process, the ...

AI Technical Summary

Problems solved by technology

In the actual control system, due to the limitation of the physical properties of the components, the actuator usually has a dead zone phenomenon, that is, the actuator has no output at low speed, and the phenomenon of no output at low speed and low speed is more obvious in the AUV heading control.

And as the working conditions and environment change in the production process, the parameters of the dead zone of the thruster are time-varying, and the existence of the dead zone causes a serious decline in the performance of the control system

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