The percentages of fruits with stem at three vibration frequencies are shown in Table 2, which shows that 10 Hz vibration resulted in less fruits with stem. The detachment condition might be affected by motion patterns. As discussed previously, tilting motion may result in flexural stress at the pedicel-fruit abscission zone and the twisting motion can result in a shear stress or torsional stress in the abscission zone. Both motion patterns might have higher potential to detach fruits without stem than other motions. According to Fig. 4a, fruits at 10 Hz experienced more times of both motion (1.1 times of twisting and 8.5 times of tilting) comparing to 14 Hz (1.7 and 5.5 times respectively) and 18 Hz (1.0 and 4.1 times respectively), which might result in more fruits without stem.