In Situ Process Monitoring: A Perspective on the Role of In Situ Process Monitoring in the Certification of Additive Manufactured Space Hardware

In situ process monitoring refers to any technology that monitors an additive manufacturing (AM) process. The range of technologies is as broad as the range of nondestructive evaluation (NDE) methods and can even extend to machine health monitoring more traditionally associated with process control (McCann et al. 2021). For example, voltage, current, and pressure sensors can be used to detect if something abnormal occurs in the regular operations of the AM machine, including the machinery, laser or arc, ventilation, wire feed, or powder recoating processes. If these sensors detect an off-nominal condition, that region of the AM build can be investigated by checking the data streams from other process monitoring technologies, or after the build using NDE.