# Design and Evaluation of a Shaping and Pruning Machine for Dwarf and Densely Planted Jujube Trees
###### Abstract
This machine can crush and recycle residual branches while pruning olive trees, but can only prune one side of the tree [31]. In 2014, Xinjiang Agricultural University designed a single-side reciprocating pruning device for grapes to solve the problem of high cost and low efficiency of manual vineyard pruning [32]. It was composed of a frame, pruning device, power system, copying frame, etc. The machine had an operating speed of 0.8 \(\mathrm{m/s}\), cutting height of 30 mm, cutter stroke of 76 mm, a simple structure, and high efficiency, but had the shortcomings of poor robustness and easy clogging. In 2015, Shihezi University developed a pruning machine for grapevines [33], which pruned the tops and sides of grapevines with a disc cutter; it was suitable for cutting thinner branches of the grapevines. In 2016, Shandong Agricultural Machinery Research Institute designed the PJS-1 two-wing pruning machine for grapes [34], which consisted of a frame, a trimming device, a transmission system and a hydraulic system. The machine controlled its tool speed through the hydraulic system, had an operating speed of 5-7.5 \(\mathrm{km/h}\), pruning width of 1400-2400 mm, and pruning height of 400-2000 mm, and could complete pruning of the left and right sides and top branches of the grapes in one operation. In 2019, Huazhong Agricultural University designed a pruning machine for citrus, consisting of a frame, a transmission device, a space track moving device, an actuator for the pruning arm, a hydraulic actuator, and a walking suspension device. The maximum missed pruning rate of the machine was 10.1%, and the qualified rate was 88% [35]. In 2020, Xinjiang Agricultural University designed a single-motor reciprocating pruning machine for grapes [36], which used a single hydraulic motor to drive a reciprocating cutter to prune single sides and tops of grapevines at the same time, with a cutting speed of 1.66 \(\mathrm{m/s}\), feeding speed of 1.46 \(\mathrm{m/s}\), clean grape stalk cutting rate of 90.66%, and stubble breakage rate of 4.71%. In 2020, [PERSON] et al. designed a wideband combination copying pruning machine for new orchards [37] comprising a frame structure, cutting device, transmission system and hydraulic system. The cutting height range of the machine was 500-4000 mm, the maximum cutting diameter was 60 mm, the missed rate of pruning was 7.3%, and the qualified rate of pruning was 90.9%. The quality of the cut section and the shape of the cut met the requirements for agronomic application. In 2021, [PERSON] et al. designed a form trimming machine for horticultural plants [38], the pruning device of which consists of multiple cutting tools that move back and forth. It takes about 8.89 \(\mathrm{s}\) to trim a single horticultural plant with this machine. Anhui Academy of Agricultural Sciences designed a pruning machine for mulberry, which includes a transmission device, a hydraulic actuator, an actuator for the pruning arm, a space track moving device, and a walking suspension device. The maximum missed pruning rate of this machine is 10%, and the qualified rate is 90% [39]. At present, the design of and research on shaping and pruning machines by domestic and foreign researchers is mainly aimed at horticultural plants with soft branches and easily broken stalks, such as vines. The cutting parts of most pruning machines use low speed reciprocating cutting tools. Due to great differences in growing information and agronomic pruning requirements for different varieties of fruit trees, existing shaping and pruning machines for fruit trees cannot meet the intensive pruning requirements for large-scale orchards of dwarf and densely planted jujube trees with hard branches. To sum up, a shaping and pruning machine that is connected with a tractor by the front suspension was designed for jujube trees to meet the demand for mechanized and rapid shaping and pruning of dwarf and densely planted jujube trees in Xinjiang.