Development and evaluation of a tractor branch shaker with float arms for apple harvesting

In this study, a branch shaker was constructed and evaluated in order to harvest apple (the variety Golden Delicious) and also decrease the oscillatory effects of shaker on the tractor. This system was made in a way that it had the capability of changing the oscillation amplitude in three levels of 20, 32 and 40 mm as well as the frequency in levels between 4-20 Hz. In order to determine the most suitable amplitude and frequency of the shaker on the separation of fruit from the branch, a factorial experiment (3×3) was conducted through a completely randomized design. In this experiment, the effect of three levels of frequency (4, 12 and 20 Hz) and three amplitudes of oscillation (20, 32 and 40 mm) on the separating percentage of the fruit were investigated. The results of variance analysis and comparing averages showed the significant effect of different levels of amplitude and frequency of the fruit on the separation of apple fruit, while the interaction effect of these two factors didn’t show any asignificant effect. 40 mm and 12 Hz were determined as the most appropriate oscillation amplitude and frequency, respectively which resulted a 94% separation of apple from the tree in a shaking time of 10 seconds.