Design and Evaluation of a Shaping and Pruning Machine for Dwarf and Densely Planted Jujube Trees

Abstract

A shaping and pruning machine for jujube trees was developed in this study to address the difficulties of high intensity and low efficiency of artificial pruning for dwarf and densely planted jujube trees in Xinjiang. The key components of the machine were designed according to the growth information and pruning technical requirements of jujube trees. Additionally, the structural and working parameters of components or parts were determined. Then, utilizing the forward speed of the machine, cutter rotation speed, and cutter diameter as influencing variables, and the missed pruning rate and stubble breakage rate as evaluation indexes, a quadratic regression orthogonal test with three factors and three levels was constructed. Meanwhile, analyses of variance and response surface were conducted to establish mathematical regression models of influencing factors and evaluation indexes, and the influence of significant factors on response indexes was analyzed. The test results were optimized, and the optimal parameter combination was obtained as follows: the rotation speed of the cutter was 2300 r/min, the diameter of the cutter was 250 mm, and the forward speed was 0.3 m/s. Then, field validation tests were conducted according to the optimal parameter combination. The results showed that the average values of the missed pruning rate and stubble breakage rate for the machine were 5.46% and 5.01%, respectively. The results indicated that the operation of the shaping and pruning machine met technical requirements for pruning jujube trees. This research contributes to rapid shaping and pruning operations in large-scale orchards of dwarf and densely planted jujube trees, which is conducive to promoting the whole mechanization management of jujube gardens in Xinjiang.