14. A Framework for Additive Manufacturing Process Monitoring & Control

Fused deposition modelling, like other additive manufacturing methods, has largely remained an open loop process in the absence of rigorous process monitoring and diagnostic functionality. By creating a framework that integrates quantitative diagnostic tools whose measurements are coordinated with the printing process and the system which commands the printer hardware, this paper demonstrates the feasibility of closing the loop in additive manufacturing systems. Specifically, this paper introduces the use of ultrasonic excitation as a means of detecting filament bonding failures introduced by manipulating the print bed temperature during the fused deposition modelling build process. Furthermore, this work demonstrates the capability of correcting these filament bonding failures using a correction mechanism introduced through tunable control of another process parameter of the printer. By demonstrating the detection and correction of filament bonding failures in situ, this work has demonstrated the progress toward fully closed loop control for fused deposition modeling processes.