LMD单道多层偏移堆积成形角度预测与控制  

Prediction and Control of Forming Angle of LMD Single-Track Multi-Layer Deflected Accumulation

作　　者：鲁俊 殷鸣[1] 谢罗峰 向锦 李伟[1] LU Jun;YIN Ming;XIE Luo-feng;XIANG Jin;LI Wei(School of Mechanical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学机械工程学院,成都610065

出　　处：《组合机床与自动化加工技术》2022年第5期92-95,共4页Modular Machine Tool & Automatic Manufacturing Technique

基　　金：国家自然科学基金项目(51705347,52075352);四川省重大科技计划专项项目(2020ZDZX0014)。

摘　　要：针对倾斜薄壁件的金属增材制造无支撑成形的成形精度问题,研究了单道多层激光熔化沉积(LMD)偏移堆积工艺的倾斜角度与重要工艺参数的相关性,设计了模糊PID控制系统,并对单因素加以控制。为预测直薄壁件的宏观倾角,设计了混合水平正交实验,得到了与激光功率、扫描速度、单层偏移量三因素相关的线性回归模型,对结果分析发现单层偏移量对倾角影响最大。针对此因素进行了动态系统辨识,通过寻优获得了非线性自回归和线性自回归两种模型,进行比较后发现非线性自回归模型拟合得更为精确,拟合度达到了86.65%。基于此模型设计了对应的模糊PID控制器和传统PID控制器,经过仿真比较,结果显示模糊PID控制器的跟踪效果更优良。Aiming at the forming accuracy problem of metal additive manufacturing unsupported forming of inclined thin-walled parts,the correlation between the inclination angle of single-pass multilayer laser melting deposition(LMD)deflected accumulation process and important process parameters was studied,and fuzzy PID controller system was designed to control the single factor.In order to predict the macroscopic inclination angle of straight thin-walled parts,a hybrid horizontal orthogonal experiment was designed,and a linear regression model related to the three factors of laser power,scanning speed,and single-layer offset was obtained.Analysis of the results found that the single-layer offset has the greatest impact on the dip angle.In view of this factor,the dynamic system identification was carried out,and two models of nonlinear autoregressive and linear autoregressive were obtained through optimization.After comparison,it was found that the nonlinear autoregressive model fits more accurately,and the degree of fit reaches 86.65%.Based on this model,the corresponding fuzzy PID controller and the traditional PID controller are designed.After simulation and comparison,the results show that the tracking effect of the fuzzy PID controller is better.

关 键 词：成形精度 倾斜角度 系统辨识 模糊PID控制 

分 类 号：TH16[机械工程—机械制造及自动化] TG506[金属学及工艺—金属切削加工及机床]