Dynamic material deposition control for large-scale additive manufacturing
Dynamic material deposition control for large-scale additive manufacturing
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DOI：
10.1080/24725854.2021.1956702
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发表时间：
2021-09
影响因子：
2.6
通讯作者：
Sepehr Fathizadan;Feng Ju;Feifan Wang;Kyle Rowe;Nils Hofmann
中科院分区：
文献类型：
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作者：
Sepehr Fathizadan;Feng Ju;Feifan Wang;Kyle Rowe;Nils Hofmann
摘要大规模增材制造涉及通过层层联合打印材料来制造零件。产品质量和工艺效率尚待解决，以保证实践中的工艺可行性。打印表面温度对这两个元素都有显著影响，并且可以通过适当地安排表面上的材料沉积来控制。对实时采集的热红外图像进行处理，将提取的热轮廓转化为描述表面散热的非线性轮廓模型。一个实时层时间控制模型制定，以确定最佳的时间来打印下一层。此外，利用打印头的机动性特性，同时考虑其机械约束，实时打印头速度控制模型制定为一个非线性混合整数规划。根据确定性有限状态最优控制和最短路径问题的范例，开发了一种新的算法来确定每层的最优打印速度轨迹。通过薄壁试件和汽车底盘两个实例对所提出的方法进行了验证。结果表明，该方法可以捕捉过程的热力学，实现质量和效率的同时改善。
Abstract Large-scale additive manufacturing involves fabricating parts by joint printing of materials layer upon layer. The product quality and process efficiency are yet to be addressed to guarantee the process viability in practice. The print surface temperature has a significant impact on both of these elements and can be controlled by properly scheduling the material depositions on the surface. The thermal infrared images captured in real-time are processed, and the extracted thermal profiles are translated into a nonlinear profile model describing the heat dissipation on the surface. A real-time layer time control model is formulated to determine the best time to print the next layer. Furthermore, exploiting the maneuverability characteristics of the printer head while considering its mechanical constraints, a real-time printer head speed control model is formulated as a nonlinear mixed-integer program. Following the deterministic finite-state optimal control and shortest path problem paradigm, a novel algorithm is developed to decide the optimal printing speed trajectory for each layer. The proposed approach was tested by two case studies, including a thin wall specimen and a car lower chassis. The results showed that the method can capture the thermodynamics of the process and achieve simultaneous improvement in both quality and efficiency.