Wu Long, Wang Aimin, Wang Kang, Xing Wenhao, Xu Baode, Zhang Jiayu, Yu Yuan
Digital Manufacturing Institute, Beijing Institute of Technology, Beijing 100081, China.
School of Mechanical and Electrical Engineering, Shandong Jianzhu University, Jinan 250101, China.
Sensors (Basel). 2024 Jan 18;24(2):613. doi: 10.3390/s24020613.
Thin-walled aluminum alloy parts are widely used in the aerospace field because of their favorable characteristics that cater to various applications. However, they are easily deformed during milling, leading to a low pass rate of workpieces. On the basis of on-machine measurement (OMM) and surrogate stiffness models (SSMs), we developed an iterative optimization compensation method in this study to overcome the machining deformation of thin-walled parts. In the error compensation process, the time-varying factors of workpiece stiffness and the impact of prediction model errors were considered. First, we performed machining deformation simulation and information extraction on the key nodes of the machined surface, and an SSM containing the stiffness information of discrete nodes of each cutting layer was established. Subsequently, the machining errors were monitored through intermittent OMM to suppress the adverse impact of prediction model errors. Further, an interlayer correction coefficient was introduced in the compensation process to iteratively correct the prediction model error of each node in the SSM along the depth direction, and a correction coefficient between parts was introduced to realize the iterative correction of the prediction model for the same node position between different parts. Finally, the feasibility of the proposed method was verified through multiple sets of actual machining experiments on thin-walled parts with added pads.
薄壁铝合金零件因其良好的特性适用于各种应用，在航空航天领域得到广泛应用。然而，它们在铣削过程中容易变形，导致工件合格率较低。在在线测量（OMM）和替代刚度模型（SSM）的基础上，本研究开发了一种迭代优化补偿方法，以克服薄壁零件的加工变形。在误差补偿过程中，考虑了工件刚度的时变因素和预测模型误差的影响。首先，对加工表面的关键节点进行加工变形模拟和信息提取，并建立了包含各切削层离散节点刚度信息的替代刚度模型。随后，通过间歇式在线测量监测加工误差，以抑制预测模型误差的不利影响。此外，在补偿过程中引入层间校正系数，沿深度方向对替代刚度模型中各节点的预测模型误差进行迭代校正，并引入零件间的校正系数，实现对不同零件间相同节点位置预测模型的迭代校正。最后，通过对带加强垫薄壁零件进行多组实际加工实验，验证了所提方法的可行性。
