TY - JOUR
T1 - Development of a robotic end-effector for apple tree pruning
AU - Zahid, A.
AU - He, L.
AU - Zeng, L.
AU - Choi, D.
AU - Schupp, J.
AU - Heinemann, P.
N1 - Funding Information:
This research was partiallyA s uFpepdoerrtaeld A bpyp rUoSpDriaAti oNnIsF under Project PEe Nw0o4u5ld4 7li kaen dto A gcicvees sspioenc iNalo t.h 1a0n0k1s036. W for the support from the Penn State College of Agricultural Sciences Stoy G. and Della E. Sunday program and Northeast Sustainable Agriculture Research and Education (SARE) Graduate Student Grant GNE19-225-33243.
Funding Information:
This research was partially supported by USDA NIFA Federal Appropriations under Project PEN04547 and Accession No. 1001036. We would like to give special thanks for the support from the Penn State College of Agricultural Sciences Stoy G. and Della E. Sunday program and Northeast Sustainable Agriculture Research and Education (SARE) Graduate Student Grant GNE19-225-33243.
PY - 2020
Y1 - 2020
N2 - Robotics and automation technologies are now used extensively in agriculture, while production operations for tree fruit crops still largely depend on manual labor. Manual pruning is a labor-intensive and costly task in apple production. Robotic pruning is a potential solution, but it involves several challenges due to the unstructured work environment. This study focused on designing an end-effector prototype for pruning considering the maneuvering, spatial, mechanical, and horticultural requirements. Branch cutting force was measured with a thin force sensor to provide guidelines for the end-effector design. The test results indicated the relationship between the force required to cut different diameter branches with an R2 value of 0.93. The end-effector was developed using two rotary motors, a pneumatic cylinder, and a pair of bypass shear blades. A three-directional linear manipulator system and a control system were built for moving the end-effector to targeted locations. A mathematical model was developed for simulation of the workspace utilization and reachable points of the end-effector. The simulation results indicated that the end-effector can be aligned in a wide range of orientations of the cutter. Field tests were conducted for validation of the simulation results and performance assessment of the end-effector. The results indicated that the end-effector with the current parameter settings successfully cut branches up to 12 mm in diameter and was able to cut branches in a wide range of possible orientations in a given 3D space. The robotic end-effector developed in this study is a core component of an automated pruning system for fruit trees. In future work, an integrated manipulator system will be developed for branch accessibility with collision-free trajectories.
AB - Robotics and automation technologies are now used extensively in agriculture, while production operations for tree fruit crops still largely depend on manual labor. Manual pruning is a labor-intensive and costly task in apple production. Robotic pruning is a potential solution, but it involves several challenges due to the unstructured work environment. This study focused on designing an end-effector prototype for pruning considering the maneuvering, spatial, mechanical, and horticultural requirements. Branch cutting force was measured with a thin force sensor to provide guidelines for the end-effector design. The test results indicated the relationship between the force required to cut different diameter branches with an R2 value of 0.93. The end-effector was developed using two rotary motors, a pneumatic cylinder, and a pair of bypass shear blades. A three-directional linear manipulator system and a control system were built for moving the end-effector to targeted locations. A mathematical model was developed for simulation of the workspace utilization and reachable points of the end-effector. The simulation results indicated that the end-effector can be aligned in a wide range of orientations of the cutter. Field tests were conducted for validation of the simulation results and performance assessment of the end-effector. The results indicated that the end-effector with the current parameter settings successfully cut branches up to 12 mm in diameter and was able to cut branches in a wide range of possible orientations in a given 3D space. The robotic end-effector developed in this study is a core component of an automated pruning system for fruit trees. In future work, an integrated manipulator system will be developed for branch accessibility with collision-free trajectories.
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U2 - 10.13031/TRANS.13729
DO - 10.13031/TRANS.13729
M3 - Article
AN - SCOPUS:85091109878
SN - 2151-0032
VL - 63
SP - 847
EP - 856
JO - Transactions of the ASABE
JF - Transactions of the ASABE
IS - 4
ER -