HOB-CNN: Hallucination of occluded branches with a convolutional neural network for 2D fruit trees
Chen, Zijue, Granland, Keenan, Newbury, Rhys, and Chen, Chao

Publication: Smart Agricultural Technology

Abstract: Orchard automation has attracted the attention of researchers recently due to the shortage of global labor force. To automate tasks in orchards such as pruning, thinning, and harvesting, a detailed understanding of the tree structure is required. However, occlusions from foliage and fruits can make it challenging to predict the position of occluded trunks and branches. This work proposes a regression-based deep learning model, Hallucination of Occluded Branch Convolutional Neural Network (HOB-CNN), for tree branch position prediction in varying occluded conditions. We formulate tree branch position prediction as a regression problem towards the horizontal locations of the branch along the vertical direction or vice versa. We present comparative experiments on Y-shaped trees with two state-of-the-art baselines, representing common approaches to the problem. Experiments show that HOB-CNN outperform the baselines at predicting branch position and shows robustness against varying levels of occlusion. We further validated HOB-CNN against two different types of 2D trees, and HOB-CNN shows generalization across different trees and robustness under different occluded conditions.

Bibtex:

@article{hobcnn2023,
  title = {HOB-CNN: Hallucination of occluded branches with a convolutional neural network for 2D fruit trees},
  journal = {Smart Agricultural Technology},
  volume = {3},
  pages = {100096},
  year = {2023},
  issn = {2772-3755},
  doi = {https://doi.org/10.1016/j.atech.2022.100096},
  url = {https://www.sciencedirect.com/science/article/pii/S2772375522000612},
  author = {Chen, Zijue and Granland, Keenan and Newbury, Rhys and Chen, Chao},
    keywords = {Deep learning, Occluded object detection, Computer vision, Convolutional neural network, Smart agriculture technology},
  }