Research on fish ranging based on line laser triangulation ranging method
For the problem of underwater single-eye non-contact measurement of fish size,it is usually necessary to measure the distance of underwater fish to obtain the three-dimensional information of its surface,this paper proposes a fish distance measurement scheme based on the laser triangulation method and conducts research on underwater laser ranging technology.According to the principle of optical path,multiple parameters need to be measured for ranging,which makes the process complex,error-prone,and slow in calculation.This paper first corrects the distortion of the image and restores its authenticity through Zhang Zhengyou's calibration method.The OpenCv open-source library is used to recognize the laser contour on the surface of the fish body,and a self-defined algorithm improves the accuracy of contour recognition.Centroid analysis is applied to the laser contour to obtain the centroid coordinates of laser brightness.By analyzing the displacement relationship between the coordinates of the laser image points and the spatial coordinates,a polynomial regression model with a one-variable fifth-order is fitted to predict the distance,simplifying the parameters.The experimental results indicate that the laser center of gravity recognition is not continuous,but can accurately identify on the fish body.The average error of the ranging model is 5.6 mm.In 80%of the tested samples,the error of the predicted results is within 7.0 mm,and the maximum error is within 2 cm of calibration,which meets the required accuracy for fish body distance measurement.The research suggests that this method can provide reference for further acquisition of surface three-dimensional information of fish body size.
laser rangingranging methodtriangulationspotfish body ranging
万方数据
维普
