Analysis of Olive Detachment Force to Improve Olive Shaker Efficiency Through Branch Modeling

Mechanical shaking enables efficient harvesting of olives, especially in hilly regions where automated farming is not feasible. This study delves into branch and olive detachment modeling to enhance the efficiency of a hand-held branch shaker. Shaking time, forces, accelerations, olive detachment forces and harvesting efficiency were experimentally measured. The fruit maturity index affected the force needed to detach the olive, with the highest value for olives at the C0 stage of maturity (5.93 N). No difference emerged among the tested shaking times (6 s and 12 s), neither in terms of harvest efficiency (mean 81.17%) nor in terms of damage (rate of 5.30). Therefore, the lower time was considered the most appropriate. Multibody and a Finite Element (FE) models were developed to investigate the branch response and the olive detachment condition. The stresses predicted by the FE harmonic analysis (about 8 MPa), based on the excitation force and shaking frequency measured during the tests, was in line with the measured olive detachment forces (3 to 8 MPa). The shaking frequency and the average branch acceleration in proximity to the shaker hook were 15 Hz and 50m/s2, respectively. Further studies could focus on the impact of the branch shaker on operator health, particularly risks from prolonged vibration exposure.