薄壁铝合金管机器人弯曲成形起皱调控优化

Control and optimization of wrinkling during robotic bending for thin-walled aluminum alloy tube

机器人管材弯曲成形技术是于工业4.0大背景下诞生的一种新型高灵活度管材弯曲成形技术,可实现细长管件的全自动化快速弯曲成形。工业机器人控制的末端弯曲装置在弯曲旋转的同时沿管材轴线方向进给,一定程度上改善了弯管件壁厚减薄的问题,但增大了起皱趋势。针对该问题,以Al6061铝合金管为对象,开展薄壁管机器人弯曲成形起皱优化调控。选取嵌入几何微缺陷后模型计算中消耗能量最低时的波长、起皱形貌以及与实际样件最为相似时的缩放因子作为最佳参数,建立了嵌入几何微缺陷的机器人管材弯曲成形有限元模型。采用几何微缺陷耦合有限元模型、响应面优化分析及成形实验相结合的方法,建立了起皱响应面回归预测模型,通过获得的响应曲面与等高线图,揭示了工艺参数耦合对Al6061铝合金薄壁管机器人弯曲成形起皱的影响规律,获得了最佳成形工艺参数,进一步验证了起皱预测模型和嵌入几何微缺陷的有限元模型的可靠性。

Born in the context of Industry 4.0,robotic tube bending technology is a new and highly flexible tube bending technology,which enables fully automatic and rapid bending of long and thin tubes.While bending and rotating,the robot-controlled end bending device can feed along the direction of the tube axis,which can improve the wall thickness reduction of bent tubes,but on the other hand increase the tendency of wrinkling.Therefore,taking Al6061 aluminum alloy tube as the object,the optimization and control of wrinkling during the thin-walled tube bending by robot were carried out.Selecting the wavelength at the lowest energy consumption during the model calculation after embedding geometric micro-defect,wrinkling morphology and scaling factor that was the most similar to the actual sample as the optimal parameters,the finite element model of robotic tube bending with embedded geometric micro-defects was established.Using the combination method of the finite element model with geometric micro-defect coupling,response surface optimization analysis and forming experiments,a response surface regression prediction model for wrinkling was established.Through the obtained response surface and contour map,the influence laws of process parameter coupling on wrinkling during robotic bending of Al6061 aluminum alloy thin-walled tube was revealed,and the optimal forming process parameters were obtained.And then the reliability of the wrinkling prediction model and the finite element model embedded geometric micro-defects were further validated.