A compact, low cost, in- process welding defects detection system based on thermal plasma emission

In this proposal, AlphaSense, Inc. (AI) and the University of Michigan (UM) detail the development of a compact, portable, and low cost in-process weld defects detection system. Key innovations of the proposed system include: a) weld defects monitoring based on plasma emission characteristics; b) use the electron temperature of the plasma as an indicator of the weld quality, c) use multiple plasma emission lines to enhance the system sensitivity, and d) the development and application of a Continuous Wavelet Transform (CWT) based peak detection algorithm to enhance the sensor sensitivity, and to reveal plasma emission signatures associated with contaminations. With these innovations, we expect that the final product of this proposal will be a compact (~4x4x2 inches), light weight (~1lb), low cost (<$1K/ unit if produced in small volume), and wearable sensor.