The most crucial problem of apple harvesting robot is to get the exact location and the maturity degree of the target. A system of apple maturity discrimination and positioning based on the multi-spectral technology and laser triangulation ranging principle is researched. Signal transmission, signal reception, signal processing, the CPU processing and several PC components are involved in the system. The distance between the apple and the device was calculated according to principle of triangulation. Ripe red apple, unripe green apple, stems and leaves have different reflectivity to red and infrared beam. The different ratio of red and infrared signal can be used to identify whether an apple is ripe. The threshold used to judge whether an apple is ripe is an experiential interval, which is acquired by several experiments.


multi-spectral vision technology triangle ranging maturity of discrimination positioning nonlinear least square method 


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Copyright information

© IFIP International Federation for Information Processing 2008

Authors and Affiliations

  • He Bei
    • 1
  • Liu Gang
    • 1
  1. 1.Key Laboratory of Modern Precision Agriculture System Integration ResearchChina Agricultural UniversityChina

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