基于3D扫描技术的木材缺陷定量化分析  

Quantitative analysis of wood defect based on 3D scanning technique

作　　者：赵鹏[1] 赵匀[2] 陈广胜[1] 

机构地区：[1]东北林业大学信息与计算机工程学院,哈尔滨150040 [2]东北农业大学工程学院,哈尔滨150010

出　　处：《农业工程学报》2017年第7期171-176,共6页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金面上项目资助(31670717);黑龙江省自然科学基金面上项目资助(C2016011);教育部新世纪优秀人才专项资助(NCET-12-0809)

摘　　要：木材缺陷检测是有效进行木材分级提高木材使用率的重要途径之一,该文提出了一种基于3D激光扫描点云数据的木材缺陷探测与量化的方法。首先,使用Artec 3D Scanner扫描木材表面后获取3D点云数据,在对3D点云数据进行预处理后,通过比较当前点Z坐标值(深度值)与设置的阈值的大小关系判定读入的点云数据是否为缺陷点;其次,采用深度优先搜索算法对筛选保留的缺陷点进行分类,并且对各个缺陷使用不同的颜色进行标注;最后,再使用积分法计算各个缺陷处所占表面积和体积。试验结果表明,该方法可以比较精确的测量木材表面孔洞等凹陷的表面积和体积,相对误差在5%内,测量精度较高,可为后续的木材分级和合理定价提供定量依据。此外,该方法使用的Artec Scanner仪器质量轻体积小(标准质量为0.85 kg,尺寸为261 mm×158 mm×64 mm),它和笔记本电脑可以组成便携式的木材缺陷定量检测系统。该系统携带方便,可应用于林场、木材加工企业及木材进出口部门的现场测定。Wood quality detection is a key issue in the wood manufacture factory or wood trade process. It consists of wood species recognition, wood physical parameter（such as density, hardness, water ratio, degree of surface roughness） prediction and wood defect detection, which are intimately connected with the efficient wood utilizations and wood prices. In the wood defect detection, the internal and external defects were inspected and processed with different schemes. It was an important way for effective wood grading and wood utilization to make the wood defect detection. In this paper, a detection and quantification scheme of wood defect was proposed based on three-dimensional（3D） laser scanning point cloud. This scheme could be used in the wood external defect detection such as cavity or tunnel. First, the Artec 3D Scanner was used to scan the wood surface to get the 3D point cloud. After preprocessing, the Z-axis coordinate value of current point was compared with the set threshold to judge whether it was a defect point. Second, a deep preferred search algorithm was used to classify the retained defect points marked with different colors. After this step, the segmented defects could be viewed with the Artec Cyclone software. Last, the integration algorithm was used to calculate the surface area and volume of every defect. In this step, every defect point was extended into a regular hexagon and a prism for the subsequent area and volume calculation by using the standard mathematical equations. The overall area or volume of every defect was computed by summarizing every defect point＇s area or volume. One detection system was realized with Visual C＋＋ programming tool, the Artec 3D Scanner and a laptop. The simulation experimental results indicated that our scheme could accurately measure the surface areas and volumes of cavity or tunnel on wood surface with measurement error of 5%, if the defect＇s depth was less than 3 mm. This scheme could give the quantitative proofs for the subsequent wood grading a

关 键 词：光学测量 扫描 体积测量 缺陷检测 缺陷量化 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术] TP242.6[自动化与计算机技术—计算机科学与技术]