Automated Process Control for Deposition-Based Manufacturing

Automated Process Control for Deposition-Based Manufacturing

A proven technology for creating parts consistently

NASA invites companies to license an active, closed-loop process control technology that improves consistency of parts made via deposition-based manufacturing. Initially developed for NASA’s electron-beam freeform fabrication (EBF3) system, this proven technology is applicable to any process that utilizes a pool of molten metal. The metal’s deposition is monitored by the control system’s sensor(s), and computer algorithms automatically make process adjustments to correct anomalies. The results are layer-to-layer and part-to-part consistency, yielding finished parts that perfectly match computer-aided design (CAD) plans.

Additional technical details are presented below. For more information about this licensing and joint development opportunity, please contact us by by e-mail or phone: or (919) 249-0327.

NASA created this technology (as well as other related technologies) as part of its effort to develop an EBF3 system for manufacturing large, complex parts in remote locations. NASA’s EBF3 system uses an electron beam to melt a metal wire and then accurately deposit the molten metal onto a substrate, building a part layer by layer according to CAD data.

Similar manufacturing systems run on an “open loop” with manual monitoring and adjustments. However, manual process control can be detrimental to part quality because an error of as little as a few hundredths of an inch can become significant when repeated over multiple layers.

NASA’s EBF3 system includes a technology for automatic process control. This closed-loop technology senses the deposition process in real time, provides feedback, and makes adjustments to correct anomalies. The result is a completely automatic manufacturing system that consistently yields high-quality parts.

How It Works

This closed-loop technology uses thermal imaging and other sensors to monitor build height and automatically make process adjustments to correct for anomalies.

The system uses one or more sensors to detect specific aspects of the manufacturing process. These aspects include fluctuation, oscillation, thermal input variations, flaws in geometry, and defects caused by lack of fusion or porosity. Analysis and evaluation of the sensors’ data is performed in near real time by computer algorithms. If the algorithm identifies any anomalies, the feedback signal triggers adjustments to the system, modifying the input parameters to maintain process consistency.

For example, the temperature of the molten pool tends to increase gradually during metal deposition, affecting the pool shape and, therefore, the bead height. Rather than perpetuate a cumulative error of too-low bead height over many layers of the part, this closed-loop process control system automatically decreases the electron beam’s input power. Such a change decreases the temperature and spread of the molten pool and increases the bead height.

Researchers at NASA’s Langley Research Center have successfully demonstrated that this technology automatically detects and corrects anomalies, ensuring that the manufacturing process runs consistently and reproducibly from the bottom to the top of the deposited part.

Why It Is Better

Consistent part quality is essential for any commercial component, and this closed-loop control system can be easily adapted to meet the process consistency requirements of various industries. This technology’s level of process consistency reduces material costs, operator costs, and the time to achieve a finished part—and it is unavailable in other metal deposition manufacturing systems.

Automated Process Control for Deposition-Based Manufacturing

A proven technology for creating parts consistently

How It Works

Why It Is Better

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