A Monocular Vision Positioning Method for Underwater Robot

Abstract

The invention provides an underwater robot monocular vision positioning method. A Doppler instrument and a gyroscope are combined o measure the linear speed and the angular speed of an underwater robot under a load system, and a state equation is obtained; four known static feature points of coordinates under an overall system are obtained, the positions of the feature points under an image system are obtained according to coordinate system changes, and a measuring equation is obtained; the state vector at the k-1 time and a covariance matrix of the state vector are known, and a Sigma point is obtained through an Unscented transform method; the measuring value at the k time is estimated through time update again; the Doppler instrument and the gyroscope are combined to measure the linear speed and the angular speed of an aircraft under the load system and the positions of the feature points under the overall system under the image system, the measuring value at the k time can be obtained, the state vector of the k time is estimated through measurement update, and a covariance matrix of the state vector at the k time is obtained. The limitation that layout of feather points in a geometric method must meet specific conditions is broken through, the defect that EKF filter can only estimate position information is overcome, and position information and the euler angle can be estimated at the same time.

Description

technical field [0001] The invention relates to the technical field of underwater visual positioning, in particular to a monocular visual positioning method of an underwater robot, which realizes the monocular visual positioning of an underwater robot through pose estimation based on nonlinear Kalman filtering. Background technique [0002] With the rapid development of ocean development, there are more and more underwater construction and construction projects, and the performance requirements for underwater action means are also getting higher and higher. Only by obtaining high-precision position and attitude information can an underwater robot achieve precise control. Underwater positioning is one of the key technologies to be solved in the development of underwater robots. For a long time, people have been devoted to the research of underwater acoustic positioning technology, and have achieved good research results in the medium and long-distance target positioning and n...

AI Technical Summary

Problems solved by technology

However, the current method of using EKF filtering is only used to estimate the position of the robot, and does not consider the Euler angle of the robot, which leads to the fact that the method cannot be effectively used for the control of underwater robots in actual use.

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