关键词: 果园作业机车架, 灵敏度分析, Kriging近似模型, 多目标优化, 层次分析法

Abstract: Aiming at the problem of heavy weight and excess strength of the orchard working machine, the structural parameters of the frame of an orchard operating machine are optimized to reduce the mass and improve the structural static and modal characteristics of the frame. The finite element model of the frame is established, and its structural static characteristics and structural modal characteristics under typical working conditions are analyzed. The structural parameters that have a greater impact on the mass, the structural static characteristics and the structural modal characteristics of the frame are selected as the design variables through the sensitivity analysis method. The sample points are designed using the optimal Latin hypercube experimental design method. Then the approximate models of the multiobjective optimization system of the characteristic parameters, such as the mass, the maximum stress, the loworder natural frequency, etc, are constructed using the Kriging method. The approximate models are optimized by integrating multiobjective genetic algorithm and analytic hierarchy process, and the optimal solution is obtained. The results show that, with the static strength of the structure is met , the mass of the optimized frame is reduced by 11.6%, and the firstorder natural frequency and the secondorder natural frequency of the optimized frame are increased by 12.3% and 7.2%, respectively, which effectively reduces the weight of the orchard operation machine and improves the frame structure modal properties.

Key words: frame of orchard operation machine, sensitivity analysis, Kriging approximate model, multiobjective optimization, analytic hierarchy process