Embedding Sensors in FDM Plastic Parts During Additive Manufacturing

In additive manufacturing, there is a necessity to qualify both the geometrical and material characteristics of the fabricated part, because both are being created simultaneously as the part is built up layer by layer. Increased availability of open source fused deposition modeling machines has expanded the parameter space for which the user has control during the build process. This work quantifies the effects of operator choices, such as print speed, printer head and build plate temperatures, layering thickness, or building in a thermally controlled or fully open environment, on the quality and reproducibility of the build. Modal analyses were performed on completed builds using an electrodynamic shaker and integrated circuit piezoelectric accelerometers embedded in the parts during the build process. Experimental measurements of the fused deposition modeled parts were benchmarked against eigenvalue analysis results for an idealized part with homogenous material properties to gauge the suitability of such analysis to fused deposition modeling additive manufacturing. Follow on work will use this embedded technique for state-of-health monitoring in deployed systems and real-time diagnostics and control of the build process.