Additive manufacturing (AM) technologies have undergone significant advancements through the integration of cooperative robotics additive manufacturing (C-RAAM) platforms. By deploying AM processes on the end effectors of multiple robotic arms, not only are traditional constraints such as limited build volumes circumvented, but systems also achieve accelerated fabrication speeds, cooperative sensing capabilities, and in-situ multi-material deposition. Despite advancements, challenges remain, particularly regarding defect generation including voids, cracks, and residual stress. Various factors contribute to these issues, including toolpath planning (i.e., slicing strategies), part decomposition for cooperative printing, and motion planning (i.e., path and trajectory planning). This review first examines the critical aspects of system control for C-RAAM systems consisting of slicing and motion planning. The methods for the mitigation of defects through the adjustment of these aspects and the process parameters of AM methods are then described in the context of how they modify the AM process: pre-process, inter-layer (i.e., during layer pauses), and mid-layer (i.e., during material deposition). The application of advanced sensing technologies, including high-resolution cameras, laser scanners, and thermal imaging, for capturing of micro, meso, and macro-scale defects is explored. The role of digital twins is analyzed, emphasizing their capability to simulate and predict manufacturing outcomes, enabling preemptive adjustments to prevent defects. Finally, the outlook and future opportunities for developing next-generation C-RAAM systems are outlined.

中文翻译：

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迈向增材制造中的智能协作机器人：过去、现在和未来


通过集成协作机器人增材制造 （C-RAAM） 平台，增材制造 （AM） 技术取得了重大进步。通过将增材制造工艺部署在多个机械臂的末端执行器上，不仅可以规避传统限制（如有限的构建体积），而且系统还可以实现更快的制造速度、协同传感能力和原位多材料沉积。尽管取得了进步，但挑战仍然存在，尤其是在缺陷产生方面，包括空隙、裂纹和残余应力。导致这些问题的因素有很多，包括刀具路径规划（即切片策略）、用于协作打印的零件分解以及运动规划（即路径和轨迹规划）。本文首先研究了 C-RAAM 系统控制的关键方面，包括切片和运动规划。然后，在它们如何修改增材制造工艺的背景下描述通过调整这些方面来减轻缺陷的方法以及增材制造方法的工艺参数：前处理、层间（即在层暂停期间）和中间层（即在材料沉积期间）。探讨了先进的传感技术（包括高分辨率相机、激光扫描仪和热成像）在捕获微观、中观和宏观尺度缺陷中的应用。分析了数字孪生的作用，强调了它们模拟和预测制造结果的能力，从而能够进行先发制人的调整以防止缺陷。最后，概述了开发下一代 C-RAAM 系统的前景和未来机会。