面向无人化取料机的毫米波雷达感知技术

Millimeter-wave radar sensing technology for unmanned reclaimer

针对散料港口无人化取料机往复取料效率低,毫米波雷达感知数据集噪声多、波动频繁、数据不平衡导致现有机器学习分类模型效果欠佳等问题,提出了一种基于改进模糊孪生支持向量机结合1-近邻算法的孪生重叠敏感边距分类器的料堆边界感知方法。首先,利用毫米波雷达获取料堆边界扫描数据并进行预处理,依据空间分布以及作业特点设计提取点云的10维特征,组成料堆点云样本数据集;其次,引入改进模糊隶属度函数的模糊孪生支持向量机,将料堆点云样本数据集划分为重叠与非重叠区域;然后,采用模糊孪生支持向量机决策边界、1-近邻算法分别对非重叠与重叠区域样本进行分类,以提高对不平衡数据集的分类能力;最后,将得到的分类结果加入感知环节,达到料堆边界感知目的。在人工作业雷达采集的数据集上的实验表明,所提出感知方法有效提高了对少数类的识别能力。现场实验表明,改进后的感知方法更接近操作员的判断,斗轮空转时间占比减少15.1%,提高了无人化取料机的作业效率,对无人化散料港口的建设具有参考意义。

Unmanned reclaimers in bulk materials ports has the problems of low reciprocating reclaiming efficiency.Meanwhile,the existing machine learning classification models are not effective because of high noise,frequent fluctuations,and unbalanced data of millimeter-wave radar sensing datasets.In this paper,a stack boundary sensing method based on improved fuzzy twin support vector machine combined with 1-Nearest Neighbor algorithm is proposed.Firstly,the millimeter-wave radar is used to obtain the stack boundary scan data and preprocess it.According to the spatial distribution and operation characteristics,the 10-dimensional features of the point cloud are extracted to form the stack point cloud sample dataset;secondly,the improved fuzzy membership function is introduced.The fuzzy twin support vector machine divides the pile point cloud sample dataset into overlapping and non-overlapping regions.Then,the fuzzy twin support vector machine decision boundary and 1-nearest neighbor algorithm are used to classify the non-overlapping and overlapping region samples respectively to improve the classification ability of unbalanced datasets.Finally,the classification results obtained are added to the perception link to achieve the purpose of sensing the boundary of the pile.Experiments on the dataset collected by manual operation radar show that the proposed perception method effectively improves the ability to recognize minority categories.Field experiments show that the improved perception method is closer to the operator′s judgment,the idle time of the bucket wheel is reduced by 15.1%,which improves the operating efficiency of the unmanned reclaimer and has reference significance for the construction of unmanned bulk materials ports.