履带拖拉机三点悬挂机构多目标优化设计

Multi-objective optimization design of three-point hitch mechanism for crawler tractors

建立履带拖拉机后置三点悬挂机构的运动学数学模型,通过分析得到农具提升过程中悬挂轴处的提升力及悬挂轴与下拉杆铰接点处的垂直上升速度与液压缸运动速度的比值。运用遗传算法的基本思想,以某型号履带拖拉机悬挂机构作为设计算例,将悬挂机构的提升能力及提升过程的平稳性和速度作为优化目标,采用线性加权和法对悬挂杆件的几何尺寸进行多目标优化。结果表明,采用基于遗传算法的优化方法优化后,三点悬挂机构的提升力增强,提升过程的平稳性明显提高。

The kinematical mathematic model of the rear mounted three-point hitch mechanism of crawler tractors was established.The lifting force at the suspension axle and the ratio of the vertical speed at the hinged joint between the suspension axle and lower rod and the speed of hydraulic cylinder during the lifting process of agricultural implements were obtained.Guided by the basic ideas of genetic algorithm and with a certain type of crawler tractor hitch system as an example,the geometry sizes of the hanging bar were optimized objectively by the linear weighted sum method in order to raise the lifting capacity of the hitch mechanism and improve the stability and speed of the lifting process.The results show that after the optimization based on the genetic algorithm,the lifting force and stability of the three-point hitch mechanism have obviously been improved.