An improved fuzzy artificial potential field obstacle avoidance method for unmanned ships based on sonar

Abstract

The invention provides an improved fuzzy artificial potential field obstacle avoidance method for an unmanned ship based on sonar, which belongs to the technical field of unmanned underwater vehicles and aims to solve the problem of using traditional artificial potential field obstacle avoidance methods for existing unmanned underwater vehicles. The target unreachability problem and the local minimum problem. The method of the present invention includes: initializing the data of the upper computer of the ground station; using the sonar ranging module to obtain the position information of obstacles around the unmanned ship; based on the improved artificial potential field algorithm, calculating the minimum heading angle of the resulting potential field; On the basis of the improved artificial potential field, the two-dimensional fuzzy control module constructed by the triangular membership function is used to determine the next position of the unmanned ship. The effect is that the present invention has the characteristics of simplicity, practicality and wide application. The use of TriTech micro-mechanical scanning sonar to detect obstacles has the advantages of low cost and low power consumption. The artificial potential field method is used as the basis to make the principle simple and easy to understand. Combined with fuzzy control, the course angle of the unmanned ship can be smoothed.

Description

technical field [0001] The invention relates to the technical field of unmanned underwater vehicles, in particular to an improved sonar-based fuzzy artificial potential field unmanned vessel obstacle avoidance method. Background technique [0002] The traditional artificial potential field obstacle avoidance method adopted by surface unmanned ships is: construct an artificial potential field including gravitational field and repulsive field in the sea environment where surface unmanned ships sail, and provide the gravitational field by the target point of navigation, The repulsion field is provided by the obstacles on the sea surface, so that the gravitational and repulsive forces acting on the unmanned ship form a resultant force, guiding the target course of the unmanned ship and moving towards the target point. Due to its simple principle, small amount of calculation, and good real-time performance, the artificial potential field method is currently widely used in the pat...

AI Technical Summary

Problems solved by technology

However, when the obstacle is located between the current position of the unmanned ship and the line connecting the target point, or the unmanned ship is affected by the repulsive force of multiple obstacles so that the repulsive force it receives is equal to the gravitational force and the direction is opposite, the unmanned ship will fall into a local minimum value point, it is impossible to judge how to move in the next step, resulting in stopping or wandering at this point, that is, there is a problem of falling into a local minimum point; when the unmanned ship is getting closer and closer to the target point, according to the traditional artificial potential field gravity It can be seen from the repulsion formula that the gravitational force of the target point is getting smaller and smaller, so if the unmanned ship passes through obstacles when it is closer to the target point, the repulsive force it receives will be much greater than the gravitational force of the target point, making it impossible for the unmanned ship to reach End point, that is, there is a target unreachable problem

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