A Novel Approach for Quantifying Impact and Abrasive Wear by Short-Range mmWave InSAR

Runtime inspection of surface wear is imperative to ascertain the production performance of a mill. Mill liners are vulnerable to impact and abrasive wear, subsequently leading to unplanned breakdown and increased downtime. This remains an open-problem owing to the dust-ridden environment of a grinding mill that challenges existing wear profiling systems. In this scenario, millimeter-waves (mm-waves) can propagate through dust and illuminate a visually occluded wear zone. This article presents a unique approach to detect and quantify wear using short-range mm-wave interferometric synthetic aperture radar (InSAR). We propose a set of algorithms to reduce defocusing of synthetic aperture radar (SAR) images in short range; automated identification of anchor points for precise InSAR image co-registration; and lastly quantification of surface wear from interferograms. Our experiments demonstrate the improvement in signal-to-noise ratio (SNR) of SAR images and efficacy of the proposed co-registration scheme in interferometric processing. Wear estimation using the resultant interferograms has been carried out with an MSE of 0.266.