Determination of Plant Height for Crop and Weed Discrimination by Using Stereo Vision System

Abstract

The stereo vision experiments were conducted under the laboratory conditions by using LabVIEW programming language. An artificial crop plant and six types of artificial weed samples were used in the experiments. The information related to the plant height is a relevant feature to classify the crop plant and weed, especially in the early growth stage. A binocular stereo vision system was established by using two identical webcams with parallel optical axes and a laptop computer to discriminate the artificial crop plant and six types of weeds correctly. The calculated depth values were compared with the physical measurements for the same points. While the measurement error of the system was less than 3.50% for the artificial crop plant, it was less than 4.20% for six artificial weed samples. There were also strong, positive and significant linear correlations between the stereo vision and physical height measurements for artificial crop plant and weed samples. Calculated correlation values (R²) between the stereo vision and physical height measurements were 0.962 for the artificial crop plant and 0.978 for the artificial weed samples, respectively. That stereo vision system could be integrated into automatic spraying systems for intra-row spraying applications.

Keywords

• 3D Depth Measurement,LabVIEW,Spraying,Stereo Vision,Weed

Ürün ve Yabancı Ot Ayrımı için Stereo Görme Sistemi Kullanılarak Bitki Yüksekliğinin Belirlenmesi

Abstract

Stereo görme denemeleri, LabVIEW programlama dili kullanılarak laboratuvar koşullarında yapılmıştır. Denemelerde, yapay bir ürün bitkisi ile altı tür yapay yabancı ot örneği kullanılmıştır. Bitki yüksekliği ile ilgili bilgi; özellikle ilk büyüme döneminde, ürün bitkisi ile yabancı otların sınıflandırılması için önemli bir özelliktir. Yapay ürün bitkisi ile altı tür yabancı otu doğru şekilde birbirlerinden ayırt etmek için paralel optik eksenli iki özdeş web kamerası ve bir dizüstü bilgisayar kullanılarak, bir binoküler stereo görme sistemi geliştirilmiştir. Hesaplanan derinlik değerleri, aynı noktalardan alınan fiziksel ölçümlerle karşılaştırılmıştır. Sistemin ölçüm hatası; yapay ürün bitkisi için %3.50'den az iken, altı tane yapay yabancı ot örneği için %4.20'den az olmuştur. Yapay ürün bitkisi ve yabancı ot örnekleri için stereo görme ile fiziksel yükseklik ölçümleri arasında; güçlü, pozitif ve anlamlı doğrusal bir korelasyon vardır. Stereo görme ve fiziksel yükseklik ölçümleri arasındaki hesaplanan korelasyon değeri (R²), yapay ürün bitkisi için 0.962; yapay yabancı ot örnekleri için ise 0.978’dir. Bu stereo görme sistemi, sıra üzeri ilaçlama uygulamaları için otomatik ilaçlama sistemlerine entegre edilebilir.

Keywords

• 3D derinlik ölçümü,LabVIEW,İlaçlama,Stereo Görme,Yabancı Ot

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