Design End-effectors for Thinning Apple in the Green Fruit Stage
Open Access
- Author:
- Pawikhum, Kittiphum
- Graduate Program:
- Agricultural and Biological Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- November 30, 2022
- Committee Members:
- Suat Irmak, Program Head/Chair
Paul Heinz Heinemann, Thesis Advisor/Co-Advisor
Long He, Committee Member
Henry Joseph Sommer, III, Committee Member
Randall Gray Bock, Special Signatory - Keywords:
- End-effector
Thinning
Green fruit Thinning
Crop load management
apples apples
mechanical properties
Physical Properties
apples thinning
Apples
Mechanical properties - Abstract:
- One essential horticultural process for apple production is thinning, which plays a vital role in determining fruit quality. Robotic technology is an alternative thinning method that reduces labor costs while still being both accurate and precise. This robotic technology successfully works through the end-effector, the only path connecting the robotic system to the environment. Two model end-effectors were designed, each using a different approach to thinning based on the size and shape of standard apples, which is the target fruit of this study. The first end-effector model thins apples one by one, while the second end-effector model preserves the king fruit of the cluster while cutting off unwanted apples. Both models have been designed and simulated using SolidWorks to study the end-effectors’ motion. The fabricated end-effector was first tested in the lab, then was tested in the apple orchard during the thinning season. A mechanism design was adopted to singulate apples, which considered the mechanical and physical properties. Model 1 of the end-effector applied an iris dome mechanism to singulate the apple one by one. This mechanism can operate the opening center that can singulate apples appropriately. Model 2 used the idea of a corkscrew to protect the king fruit and remove unwanted apples. The advantage of this design is a time-saving process. Model 2 should be improved for better singulation performance. Both models have their advantages and disadvantages, and this end-effector is a key part of the robotic system.