Researchers from Penn State University have developed an automated pruning system with a robotic cutting mechanism attached to help fruit growers automate the maintenance of their fruit trees.

Faced with increasing labor costs and labor shortages, fruit tree growers manually prune their fruit trees, which is a time-consuming process that impacts both the quality and quantity of fruit. Yet manually pruning fruit trees accounts for an estimated 30 to 50 labor hours per acre. As such, the Penn State team developed the system with the cutting mechanism, or end effector, to reduce costs and improve productivity.

Source: Penn State University

To develop the end effector, researchers determined the force required to cut branches using a pair of manual pruners outfitted with a sensor. Researchers then used that data to develop the end effector, which is composed of a pneumatic cylinder, two rotary motors and a pair of pruning cutters. Housing the end effector is a three-directional linear manipulator, which is guided by an embedded microcontroller system with a user interface that relies on an interactive mathematical program that enables visual calculations.

Once developed, the prototype was able to cut branches to roughly half an inch in diameter. Likewise, the researchers reported that the end-effector could cut branches at various orientations within a given space. The prototype demonstrated the manual dexterity to operate within a tight space among several branches and orient itself via trajectory planning to reach the branches targeted for pruning.