高级检索

地理加权主成分分析与自适应α-shape的带式输送机堆煤智能识别方法

Intelligent recognition method for coal stacking on belt conveyors based on geographically weighted principal component analysis and adaptive α-shape

  • 摘要: 针对复杂工况下煤矿带式输送机传统堆煤识别方法准确性、稳定性不高和三维点云的煤堆表面三维重建完整性不足导致堆煤误判等问题,提出一种地理加权主成分分析(GWPCA)和自适应α-shape三维点云重建的堆煤智能识别方法。针对深度相机全视角采集点云数据量大导致处理速度慢、识别率低等问题,通过手动绘制ROI(Region of Interest)局部区域确定带式输送机表面目标点云数据,并采用直通滤波有效滤除冗余点和噪点、孤立数据,实现带式输送机表面煤堆点云数据快速、准确获取。针对煤堆侧表面点云缺失问题,构建基于地理加权主成分分析(GWPCA)的改进型泊松表面重建模型,通过输送带面与煤堆上表面的空间拓扑关系,结合法向约束机制实现点云数据补全,并采用最小凸包筛选算法消除伪平面干扰。针对不同形态煤堆与输送带表面分割问题,建立煤堆底部边界紧凑度和局部曲率标准差的函数关系,实现自适应α-shape算法的煤堆底部轮廓边界提取,准确分割煤堆点云数据并计算其等效宽度。针对采用单一参数的堆煤识别方法易受局部敏感值影响导致识别结果出现偏差的问题,提出一种基于煤堆宽/高最大值和等效值联合判别的堆煤识别方法,采用局部点云高度值的核密度函数期望值计算等效高度和最小包围盒计算最大宽、高值。搭建带式输送机堆煤智能识别试验平台,开展不同试验环境下的堆煤识别验证试验,结果表明:正常光照环境下,最大宽度和高度检测的平均误差分别为0.40 cm、0.35 cm,单帧宽/高等效值与最大值之间的相关系数为0.983,平均检测速度为每帧1.15 s,有效反映了真实的煤堆状态;粉尘环境下,最大宽度和高度检测的平均误差分别为0.46 cm、0.47 cm,单帧平均识别速度为1.23 s。等效值能准确反映煤堆整体形态变化,实现了堆煤状态的准确、可靠判别。

     

    Abstract: Aiming at the problems of low accuracy and stability of traditional coal pile identification methods for coal mine belt conveyors under complex working conditions and insufficient integrity of three-dimensional point cloud three-dimensional reconstruction of the coal pile surface, which leads to misjudgment of coal pile, this paper proposes an intelligent coal pile identification method based on geographically weighted principal component analysis (GWPCA) and adaptive α-shape three-dimensional point cloud reconstruction. Aiming at the problems of slow processing speed and low recognition rate caused by the large amount of point cloud data collected from the full view of the depth camera, the target point cloud data on the surface of the belt conveyor is determined by manually drawing the ROI(Region of Interest) local area, and the direct filtering is adopted to effectively filter out redundant points, noise points and isolated data. Realize the rapid and accurate acquisition of point cloud data of coal piles on the surface of belt conveyors. Aiming at the problem of missing point clouds on the side surface of coal piles, an improved Poisson surface reconstruction model based on geographically weighted principal component analysis (GWPCA) is constructed. Through the spatial topological relationship between the conveyor belt surface and the upper surface of the coal pile, the point cloud data completion is achieved by combining the legal direction constraint mechanism, and the minimum convex hull screening algorithm is adopted to eliminate the pseudo-plane interference. Aiming at the problem of surface segmentation of coal piles of different shapes and conveyor belts, the functional relationship between the compactness of the bottom boundary of the coal pile and the standard deviation of local curvature is established to realize the extraction of the bottom contour boundary of the coal pile by the adaptive α-shape algorithm, accurately segment the point cloud data of the coal pile and calculate its equivalent width. Aiming at the problem that the coal pile identification method using a single parameter is easily affected by local sensitive values, resulting in deviation in the identification results, a coal pile identification method based on the joint discrimination of the maximum width/height of the coal pile and the equivalent value is proposed. The expected value of the kernel density function of the local point cloud height value is used to calculate the equivalent height, and the minimum bounding box is used to calculate the maximum width and height values. An intelligent recognition experimental platform for coal pile on belt conveyors was established, and verification experiments for coal pile recognition under different experimental environments were carried out. The results show that under normal lighting conditions, the average errors of the maximum width and height detection are 0.40 cm and 0.35 cm respectively, and the correlation coefficient between the equivalent value of single frame width/height and the maximum value is 0.983, and the average detection speed is 1.15 seconds per frame, effectively reflecting the real state of the coal pile. In a dusty environment, the average errors of the maximum width and height detection are 0.46 cm and 0.47 cm respectively, and the average recognition speed of a single frame is 1.23 seconds. The equivalent values can accurately follow the overall shape changes of the coal pile, achieving accurate and reliable discrimination of the coal pile state.

     

/

返回文章
返回