@article{Alzoheiry_Ghonimy_Abd El Rahman_Abdelwahab_Hassan_2020, title={Improving olive mechanical harvesting using appropriate natural frequency}, volume={51}, url={https://www.agroengineering.org/jae/article/view/1057}, DOI={10.4081/jae.2020.1057}, abstractNote={<p>The good performance of olive mechanical harvesting by shaking depends on the suitable values of limb vibrator operating parameters (frequency and amplitude). Mathematical models of a single degree of freedom (<em>S.D.F.M</em>) and two degrees of freedom (<em>T.D.F.M</em>) were used to estimate the natural frequency (<em>F<sub>N</sub></em>) of olive fruit stem system. The results from these models indicated that the <em>F<sub>N</sub></em> values were 33.9, 31.9, and 28.0 Hz for the full mature stage, half-ripe olive, and full-ripe olive respectively. Branch vibrator was operated at three levels of frequency 25, 30 and 35 Hz and 3 levels of amplitude 25, 30 and 35 mm at a vibration time of 10 s. Measurements covered the fruit removal percentage (<em>FRP</em>) and degree of full-ripe fruit selectivity (<em>DS</em>). The results showed that the maximum <em>FRP</em> value, 90.6%, was achieved at a frequency of 35 Hz and amplitude of 25 mm while the maximum <em>DS</em> value, 78.58%, was obtained at 25 Hz frequency and 25 mm amplitude.</p>}, number={3}, journal={Journal of Agricultural Engineering}, author={Alzoheiry, Ahmed and Ghonimy , Mohamed and Abd El Rahman, Eid and Abdelwahab, Ossama and Hassan, Ahmed}, year={2020}, month={Sep.}, pages={148–154} }