考虑静柔度约束的A3并联动力头轻量化设计

研究一种考虑静柔度约束的3自由度并联动力头——A3头的轻量化设计方法。该方法针对航空铝合金结构件高速铣削工艺,首先建立静柔度约束,然后建立部件柔度、质量与设计参数间的响应面模型,进而将A3头的设计问题归结为一类以静柔度和几何干涉为约束条件,以运动部件质量最轻为目标的有约束非线性设计问题,并借助多岛遗传算法(MIGA)求解。仿真验证表明,与原设计相比,在运动部件质量增加3.6%的前提下,系统的静柔度降低超过50%,低阶固有频率提高30%。该方法为此类装备的工程设计提供一种有效手段。

Lightweight Design of the A3 Spindle Head Based on the Compliance Constraint of the End-effectors

An approach for the lightweight design of a 3-DOF spindle head—A3 head designed for high-speed milling of large aircraft structural components is presented. The approach can be implemented by two steps:① formulation of the compliance bounds in the local coordinate system according to the processing parameters for high-speed milling,② minimization of the overall weight of the movable components subject to the compliance and geometrical constraint using the response surface method and the multi-island genetic algorithm (MIGA) integrated in iSIGHT. Compared to the original design, the simulation results show that the compliance of the system can be decreased by more 50%, and the first order frequency can be increased by 30% at the cost of increasing the weight of movable components by just 3.6%. The approach has been successfully employed to design the equipment.