手持摇枝式酸枣振动采摘装置设计与试验

Design and Experiment of Hand-held Shaking Branch Type Jujube Vibration Picker

摘要:

针对酸枣收获过程中人工采收效率低、大型机械采收困难等问题，设计了手持摇枝式酸枣振动采摘装置。通过建立酸枣“果实-枝条”单摆动力学模型，分析受迫振动下果实脱落条件，求解动力学模型，确定影响酸枣采摘效果的主要影响因素为振动频率、振幅、夹持位置；利用ANSYS仿真软件对酸枣植株模型进行自由模态响应与谐响应分析，结果表明：当振动频率为4~12 Hz、振幅为10~20 mm、夹持位置为0.3~0.7时，主枝、挂果枝位移明显且对树体损伤较小。为确定采摘装置最佳工作参数，以酸枣摘净率为评价指标，进行三因素三水平振动采摘试验，得到酸枣摘净率和各影响因素的数学回归模型，利用Design-Expert软件对试验数据和响应曲面进行分析优化，确定最佳工作参数组合为：振动频率5.91 Hz、振幅15.30 mm、夹持位置0.45，此时酸枣摘净率为93.33%，验证试验表明，酸枣摘净率为94.18%，与优化值接近，模型优化可靠。

Abstract:

The hand-held shaking branch jujube harvester was designed to solve the problems of low manual harvesting efficiency and difficulty of large-scale mechanical harvesting in the process of jujube harvesting. By establishing the “fruit-branch” single pendulum dynamic model of jujube, the conditions of fruit shedding under forced vibration were analyzed, the dynamic model was solved, the main influencing factors affecting the picking effect of jujube were determined as vibration frequency, amplitude and clamping position. The free modal response and harmonic response analysis of the jujube plant model were carried out by ANSYS simulation software. The results showed that when the vibration frequency was 4~12 Hz, the amplitude was 10~20 mm, and the clamping position was 0.3~0.7, the displacement of the main branch and the hanging fruit branch was obvious and there was less damage to the tree. In order to determine the optimal working parameters of the picking device, the three-factor and three-level vibration picking test was carried out with the picking rate of jujube as the evaluation index. Mathematical regression model of picking jujube and the influencing factors were obtained. The experimental data and response surface were analyzed and optimized by Design-Expert software. The optimal working parameters were determined as follows: the vibration frequency was 5.91 Hz, the amplitude was 15.30 mm, the clamping position was 0.45. At this time, the picking rate of jujube was 93.33%. It can be seen through the validation test that the picking rate of jujube was 94.18%, which was similar to tlee optimized values, indicating that the optimized model was reliable.