Real-time monitoring of optimum timing for harvesting fresh tea leaves based on machine vision

Authors

  • Liang Zhang 1. College of Engineering, Hunan Agricultural University, Changsha 410128, China; 2. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China
  • Hongduo Zhang 1. College of Engineering, Hunan Agricultural University, Changsha 410128, China; 2. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China
  • Yedong Chen College of Engineering, Hunan Agricultural University, Changsha 410128, China
  • Sihui Dai College of Horticulture and Landscape, Hunan Agricultural University, Changsha 410128, China
  • Xumeng Li 1. Agricultural College, Hunan Agricultural University, Changsha 410128, China; 2. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China
  • Imou Kenji Department of Biological and Environmental Engineering, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-0033, Japan
  • Zhonghua Liu College of Horticulture and Landscape, Hunan Agricultural University, Changsha 410128, China
  • Ming Li 1. College of Engineering, Hunan Agricultural University, Changsha 410128, China; 2. School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China; 3. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China

Keywords:

agricultural machinery, fresh tea leaves, machine vision, intelligent recognition, real-time monitoring

Abstract

The harvesting time of fresh tea leaves has a significant impact on product yield and quality. The aim of this study was to propose a method for real-time monitoring of the optimum harvesting time for picking fresh tea leaves based on machine vision. Firstly, the shapes of fresh tea leaves were distinguished from RGB images of the tea-tree canopy after graying with the improved B-G algorithm, filtering with a median filter algorithm, binary processing with the Otsu algorithm, and noise reduction and edge smoothing using open and close operations. Then the leaf characteristics, such as leaf area index, average length, and leaf identification index, were calculated. Based on these, the Bayesian discriminant principle and method were used to construct a discriminant model for fresh tea-leaf collection status. When this method was applied to a RGB tea-tree canopy image acquired at 45° shooting angle, the fresh tea-leaf recognition rate was 90.3%, and the accuracy for fresh tea-leaf harvesting status was 98% by cross validation. Hence, this method provides the basic conditions for future tea-plantation operation and management using information technology, automation, and intelligent systems. Keywords: agricultural machinery, fresh tea leaves, machine vision, intelligent recognition, real-time monitoring DOI: 10.25165/j.ijabe.20191201.3418 Citation: Zhang L, Zhang H D, Chen Y D, Dai S H, Li X M, Imou K, Liu Z H, et al. Real-time monitoring of optimum timing for harvesting fresh tea leaves based on machine vision. Int J Agric & Biol Eng, 2019; 12(1): 6–9.

Author Biographies

Liang Zhang, 1. College of Engineering, Hunan Agricultural University, Changsha 410128, China; 2. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China

College of Engineering

Yedong Chen, College of Engineering, Hunan Agricultural University, Changsha 410128, China

College of Engineering

Sihui Dai, College of Horticulture and Landscape, Hunan Agricultural University, Changsha 410128, China

College of Horticulture and Landscape

Xumeng Li, 1. Agricultural College, Hunan Agricultural University, Changsha 410128, China; 2. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China

Science College

Imou Kenji, Department of Biological and Environmental Engineering, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-0033, Japan

Department of Biological and Environmental Engineering, Graduate School of Agricultural and Life Sciences

Zhonghua Liu, College of Horticulture and Landscape, Hunan Agricultural University, Changsha 410128, China

College of Horticulture and Landscape

Ming Li, 1. College of Engineering, Hunan Agricultural University, Changsha 410128, China; 2. School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China; 3. Hunan Agricultural Aviation Advanced Technology Engineering Research Center, Changsha 410129, China

College of Engineering

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Published

2019-02-01

How to Cite

Zhang, L., Zhang, H., Chen, Y., Dai, S., Li, X., Kenji, I., … Li, M. (2019). Real-time monitoring of optimum timing for harvesting fresh tea leaves based on machine vision. International Journal of Agricultural and Biological Engineering, 12(1), 6–9. Retrieved from https://ijabe.migration.pkpps03.publicknowledgeproject.org/index.php/ijabe/article/view/3418

Issue

Section

Applied Science, Engineering and Technology