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

Year 2020, Volume: 17 Issue: 1, 97 - 107, 26.01.2020

Ömer Barış Özlüoymak

https://doi.org/10.33462/jotaf.626709

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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