基于TOF摄像机的植物叶态萎蔫辨识研究  

Identification of Plant Leaf Wilting Using TOF Camera

作　　者：张新[1] 高超[1] Martin Kraft 赵燕东[1] 

机构地区：[1]北京林业大学工学院,北京100083 [2]德国联邦农业林业和渔业研究所农业技术分所,布伦瑞克38116

出　　处：《农业机械学报》2016年第5期275-280,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(31371537);北京市教育委员会科学研究与研究生培养共建项目(BLCXY201520)

摘　　要：为定量辨识植物叶态的萎蔫程度,定义了基于离散时域傅里叶变换的萎蔫指数,搭建了一套植物叶态采集系统,以黄瓜和绿皮西葫芦幼苗为试验样品,采用植株根部快速失水与汲水的方法,控制植株叶片处于不同程度的萎蔫状况,使用TOF摄像机获取叶态3D图像信息,对图像进行去噪、阈值分割、点积运算等处理,得到目标叶片的三维点云数据,运用离散时域傅里叶变换计算其萎蔫指数。通过对黄瓜单片叶和绿皮西葫芦多片叶在植物失水、叶片萎蔫阶段和植物吸水、叶片恢复阶段的萎蔫指数定量对比分析,以及对叶片萎蔫指数在整个植物水分胁迫过程的单因素方差分析,显著性分别为0.890 4、0.292 2、0.903 6,均大于0.05,验证了基于TOF摄像机的叶态萎蔫定量辨识方法的可行性与准确性。Leaf wilting is a common phenomenon in plants. Wilting detection is of high importance for plant precision management. In this study,the 3D image of plant leaf was collected using a time-of-flight（ TOF） camera to quantificationally identify the degree of plant leaf wilting. The 3D information of targeted leaf was examined by the custom wilting index based on discrete time Fourier transform,in which the leaf is equivalent to a mathematical surface in 3D space. Rapid dehydration and rehydration method was used to make plant leaf state different wilting degrees. The image acquisition experiment was proceeded by a acquisition system based on the seeding of cucumber and zucchini. De-noising,threshold segmentation and dot product were used in image preprocessing after the images were collected,and then the wilting index was calculated. The experiments were divided into three periods,which means,dehydration period Ⅰ,rehydration period and dehydration period Ⅱ,and the trend of wilting index was favorable at each stage. The universality was simulated through the variance analysis of a piece of leaf and different pieces of leaf from the same plant. The significance levels are respectively 0. 890 4,0. 292 2 and0. 903 6,which are all larger than 0. 05. In general,the feasibility and accuracy of the identification of leaf wilting using TOF camera are verified. As leaf wilting embodys in many aspects because of different kinds of factors,control variate method was used in this paper. The identification of outdoor plant leat wilting needs to be intensively studied.

关 键 词：植物 叶态萎蔫 TOF摄像机 傅里叶变换 机器视觉 

分 类 号：S24[农业科学—农业电气化与自动化] Q945.78[农业科学—农业工程]