ObjectiveHarvesting is labor intensive work in planting, orchard harvest environment is relatively complex, harvest machine industry research is relatively weak in our country, harvest robot technology in the current garden application still has some limitations, so the development of auxiliary artificial harvest equipment has a real social and economic significance.

MethodFor the spherical fruit with stem like the apple, a peduncle locking-two plate separation harvest method was proposed, and the corresponding harvestor was designed. The overall structure for the harvestor was under-actuated, the crank rocker mechanism was designed for the peduncle locking mechanism, the fixed plate and the floating plate were designed as the branch fruit separation mechanism, slider-crank mechanism was used as a handheld drive unit, through the method of steel wire and the wire coiling wheel, the output of the slider movement was firstly transmitted to the crank rocker mechanism, two sets of symmetrical structure and dimension peduncle locking mechanisms were driven to lock the peduncle, and then the floating plate was driven to move down, together with the fixed plate, the branch and apple were separated to finish the harvest.

ResultThe geometrical parameters of the driving unit and the peduncle locking mechanism were analyzed. The 5.5° rotation of the handle in the driving unit generated a rotation of 87° for the peduncle locking mechanism, and further the double-plate separation with a distance of 50 mm. The peduncle locking mechanism was in the reverse dead point position when locking the peduncle, which ensured the reliability of the locking. Adams software was used to simulate the process of the peduncle locking and double plate separation, the feasibility of picking the under-actuated structure was approved, and the output curve vibration in the process of peduncle locking was explained, the simulation of the driving force in the process of harvesting was obtained, the prototype experiment was successfully completed with the peduncle locking-branch fruit separation achieved.

ConclusionThe method of peduncle locking-branch fruit separation method and related harvestor are proved to be feasible in the real manipulation, and they can be applied to help the artificial fruit harvest.