针对液压支架优化设计初值选择困难的问题,基于可视优化设计思想提出将Euler—Savary方程和拐点圆生成技术应用于支架直线导路机构的设计.在给定前、后连杆与底座铰接点位、掩护梁与顶梁铰点位置及掩护梁在该点运动方向的条件下,建立以后连杆方位角和拐圆位置角为参量的数学模型,得到所有具有二阶以上密切直线机构的精确解.计算包括直线性能在内的设计者感兴趣的各种机构属性并实现属性信息的图形可视化,施加设计约束构建机构可行域,引导设计者在可行域内快速准确地寻找在指定采高范围的具有最小直线偏差的机构,或在给定允许偏差的条件下具有最大支架调高的机构,为液压支架优化设计提供具有先天优势的机构初始值.
It is difficult for designers to determine proper initial parameters for the optimal design of hydraulic supports. Based on the thought of visualized optimization design, the Euler-Savary equation and the inflection circle generation technology were applied to designing an approximate straight-line linkage for a hydraulic support. Firstly, some conditions were determined such as the pivot points which link the base with the front and back rod, the position of the pivot between the caving shield and roof beam, and the motion direction of the caving shield. Then, a mathematical model was established with the direction angle of the back linkage and the position angle of the inflection circle as design parameters, and it can be solved for all possible mechanisms with at least the second-order osculating straight- line. Mechanism property graphs of interest were computed and graphical visualization of the property information was implemented. Feasible solution regions adhering to design constraints were visually represented, which can rapidly guide designers to find the optimal mechanism with the minimum deviation for a given mining height, or the one with the maximum height for a given deviation, and provides a group of preliminary values with inherent advantage for the optimization design of hydraulic supports.