A study on the use of a mechanical shaker for harvesting orange trees

Abstract In this study, a limb-shaking mechanical shaker prototype for efficient orange harvesting was fabricated and field tested. The prototype, which was fabricated locally, was evaluated at a fixed vibration amplitude of 50 mm under three tractor PTO speeds of 200, 350, and 450 rpm (3.33, 5.83, and 7.5 Hz) and shaking durations of 15, 30, and 45 s. The detachment efficiency increased significantly (p < 0.001) with both the PTO speed and shaking time, whereas their interaction was not significant. The power demand and specific energy increased with increasing PTO speeds and longer shaking periods, whereas shorter shaking durations increased field productivity by allowing more trees to be harvested per hour despite a modest reduction in detachment. Tukey’s HSD test revealed that intermediate treatments, particularly 350 rpm × 30 s (81.4% detachment, 3.14 kWh t⁻¹) and 450 rpm × 30 s (78.3%), were statistically comparable to the highest-efficiency treatment (450 rpm × 45 s, 88.6%). The combination of 350 rpm for 30 s provided an optimal balance between detachment efficiency, energy use, and throughput, achieving 81.4% fruit removal at moderate power requirements. These findings highlight that a medium PTO speed and shaking time can maximize energy-efficient mechanical harvesting of oranges while minimizing unnecessary energy expenditure.