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The mechanization of red jujube industry is a high-potential agricultural research field in China. In this study, a vibration harvesting device has been developed for jujube trees that features adjustable vibration frequency and amplitude. The device is designed to make jujube trees vibrate with varying diameters by utilizing different vibration frequencies and amplitudes according to the tree’s size such that jujubes can be harvested efficiently. The study completed the structural design of excitation and fruit collection mechanisms based on the working principle of vibration harvesting. The red jujube excitation mechanism was dynamically simulated using ADAMS, and it was found that the acceleration at the end of the vibration rod of the mechanism had a tendency to sharply increase and decrease, which was conducive to the vibration shedding of red jujube. A collision model between the red jujubes and the fruit collection umbrella was constructed, and the fruit collection mechanism was structurally simulated using ANSYS. The tests showed that the device effectively harvested red jujubes from nine types of jujube trees with diameter ranges of 29.15–31.26 mm, 49.56–52.34 mm, and 65.23–73.25 mm. The average net harvesting rates were 93.98%, 94.71%, and 94.33%, and the average fruit collection efficiencies were 95.78%, 89.43%, and 85.04%, respectively. These results demonstrate the effectiveness of the excitation and collection mechanisms and provide a theoretical basis for the development of vibratory harvesting devices for red jujubes.

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