Damask rose (rosa damascena) is a highly drought-tolerant and low-water plant with the ability to endure a variety of climatic conditions. Given the recent water scarcity crisis in Iran, it has become increasingly necessary to consider growing low-water plants such as roses. This species can be planted in regions of Iran with no rich soil and adequate water sources. The most delicate and significant step in the cultivation of damask roses is harvesting because after blooming, the flower does not last long on the branch, and if not picked timely, it turns white and falls off within 24 h. Furthermore, the sooner the flowers are harvested, the more essence and higher quality they provide. On the other hand, the harvesting cost amount to approximate more than 50% of the cultivation cost of damask rose. Hence, it has been of great interest for researchers to consider machine harvesting this product. Manufacturers and researchers have investigated the use of machine vision systems to detect and locate the blooms on the shrub and command a robotic system to harvest the flowers. To address the shortfalls of previous designs, the present research designs and fabricates a four-degree-of-freedom (DOF) robotic system in which multiple robotic harvesting units can be mounted on a frame base to accelerate the process. The designed and fabricated robotic system is composed of three arms and a lifting mechanism, providing the system with 4 DOF motion in total. The lifting mechanism includes a stepper motor and an ensemble of timing belts and driven and driving pulleys, using which the arms are placed at the right height. Three individual motors supply the angular motion of the arms in the horizontal plane. Inverse kinematics is applied to convert the target location's coordinates in the three-dimensional space into the necessary angular values to rotate the motors. A user interface (UI) was designed to register the 3D coordinates of the target location for system eva‎luation purposes. This harvesting unit was examined in terms of precision and speed in different directions. The fabricated apparatus is eva‎luated by presenting different locations. The operating speed was obtained to be 4.5 to 8 cms-1 in the horizontal plane and a constant rate of 1.9 cms-1 in the vertical direction. The arms' motion precision had an average error of 3.4 cm in the horizontal plane, which can be mitigated to an acceptable rate given the inclusion radius of the harvesting device. Moreover, there was an error of 0.5 cm in the apparatus's motion precision in the vertical direction regardless of the drop; the error increased to 1.5 cm upon adding weights as the weight of the harvesting device, leading to bending and angular displacement of the arm joints in addition to vertical error. The error can be resolved if the given value is added to the UI-registered values. Additionally, to remove the vertical drop following movement in the horizontal plane, a linear regression equation with a coefficient of determination of 71% was provided, resulting in considerable error reduction.

احمد ميره اي

احمد ميره اي

احمد ميره اي , علي نيك بخت