Sigma Labs, the developer of the PrintRite3D brand of quality assurance software, has announced the publication of a US Patent Application titled ‘Multi-sensor quality inference and control for additive manufacturing processes’.
The patent-pending technology (No. US 2016/ 0185048), which was published in June 2016, seeks to analyse the quality during an additive manufacturing process. It also relates to the characterisation of material properties using acoustic signals emitted during AM which can be used in addition to optical signals to simplify the qualification of printed parts.
Sigma Labs believes its multi-sensor quality inference system is capable of discerning three quality issues. The first of these concerns process anomalies, uncorrelated to process inputs, while the second relates to process variations, or differences between desired process parameters and operating conditions. The third concerns the structure and properties of the material(s) involved in the additive manufacturing process. It all adds up, the company believes, to the embodiment of the use of gathered sensor data, enabling users to evaluate and control additive operations in real time.
For Mark Cola, Sigma Labs CEO, the application of this patent serves as a yardstick for the company’s performance as an influential additive manufacturing quality assurance player.
“We are at the forefront of a new era in additive manufacturing and are very pleased to announce the publication of this patent which evidences our leadership in real time process control capabilities,” Cola said. “Crucial to our continued growth and emerging market leadership is securing our intellectual property portfolio. The publication of this patent application further serves these goals.”
The patent, which has a priority date of November 18th 2014, describes how optical sensors can be used to measure oscillations in the melt pool, and how these readings could be augmented by artificially illuminating the melt pool with a laser to help collect spectacular reflections that include oscillation frequency information. This application also describes how an acoustic sensor can be used to acoustically monitor a build process by listening for micro-cracking occurring as a workpiece is being built and may be used to eliminate post-build quality control processes such as CT scanning which adds an extra process to production and can be quite time intensive.
