双能X射线透射识别煤矸仍存在厚度、硬化、余辉和扇形效应等缺陷，面向5～150 mm宽厚度煤矸分选参数波动大、识别率低。为此，提出一种基于几何特征约束的煤矸双能X射线透射多维度识别方法。该方法通过目标图像最小外接圆直径和区域面积两个几何特征区分煤矸厚度，约束X射线透射响应特征的空间分布，进而从多个维度特征削弱缺陷影响。以少量低密度煤和高密度矸石，获取X射线透射响应特征、位置特征和几何特征，结合Relief-F特征选择建立强特征组合。检验多种分类器的识别性能，选取中等高斯SVM作为多维度方法的分类模型。以强特征组合作为输入，自动创建最终决策模型并分类未知煤矸像素点，通过像素变换图像处理方法获取分选参数p值。结果显示，p值与煤矸密度呈强线性相关，利用密度可选取p值调控分选。而p值与煤矸厚度呈现弱线性相关，宽厚度范围内p值离散程度小、可分性好，赋予分选参数较大调整空间。批量试验验证结果显示，多维度法预排矸分选参数p值为33.01%，以此分选参数对不同密度、不同煤种煤矸识别，整体识别率达99.57%。对5～150 mm厚度范围原煤预排矸整体识别率达99.37%。相比较H-L法、R-L法，多维度法识别率更高，面向不同厚度煤矸计算得到的p值精度高、一致性更好。印证了几何特征约束下多维度识别方法的有效性及分选参数调控优势，为现有双能X射线煤矸分选装置识别算法提供了设计参考。

The dual energy X-ray transmission identification of coal gangue still faces challenges in thickness, hardening, afterglow, and fan-shaped effects, among which the parameters for 5-150 mm wide thickness coal gangue separation fluctuate significantly and the recognition rate is to be improved. Therefore, this paper proposes a multi-dimensional identification method of dual-energy X-ray transmission of coal gangue based on geometric feature constraints. This method distinguishes the thickness of coal gangue by two geometric features of the minimum circumscribed circle diameter and area of the target image, restricts the spatial distribution of X-ray transmission response characteristics, and then weakens the influence of defects from multiple dimensions. With a small amount of low-density coal and high-density gangue, the paper obtains X-ray transmission response characteristics, position characteristics, and geometric characteristics, and combine them with Relief-F feature selection to establish a strong feature combination. To test the recognition performance of multiple classifiers, medium Gaussian SVM is selected as the classification model for multi-dimensional methods. Taking strong feature combinations as input, the final decision model and classification of unknown coal gangue pixels are automatically created, and the separation parameter p-value is obtained through pixel transformation image processing method. The results show that there is a strong linear correlation between p-value and coal gangue density, and density can be used to select p-value to regulate sorting. The p-value shows a weak linear correlation with the thickness of coal gangue. Within a wide thickness range, the p-value has a small degree of dispersion and good separability, giving separation parameters a large adjustment space. The mass experimental verification results show that the p-value of the multi-dimensional method for pre discharge gangue separation parameter is 33.01%. Using this separation parameter to identify coal gangue with different densities and coal types, the overall recognition rate reaches 99.57%. The overall recognition rate of raw coal pre discharge gangue in the thickness range of 5-150 mm is 99.37%. Compared with H-L method and R-L method, the multi-dimensional method has higher recognition rate, and the p-value calculated for coal gangue with different thickness has higher accuracy and better consistency. It demonstrates the effectiveness of multi-dimensional recognition methods under geometric feature constraints and the advantages of separation parameter regulation, which is of design reference meaning for current dual energy X-ray coal gangue separation device recognition algorithms.