Towards online monitoring and data-driven control: a study of segmentation algorithms for infrared images of the powder bed

An increasing number of selective laser sintering and selective laser melting machines use off-axis infrared cameras to improve online monitoring and data-driven control capabilities. However, there is still a severe lack of algorithmic solutions to properly process the infrared images from these cameras that has led to several key limitations: a lack of online monitoring capabilities for the laser tracks, insufficient pre-processing of the infrared images for data-driven methods, and large memory requirements for storing the infrared images. To address these limitations, we study over 30 segmentation algorithms that segment each infrared image into a foreground and background. By evaluating each algorithm based on its segmentation accuracy, computational speed, and robustness against spatter detection, we identify promising algorithmic solutions. The identified algorithms can be readily applied to the selective laser sintering and selective laser melting machines to address each of the above limitations and thus, significantly improve process control.

[1]  J. Kruth,et al.  Benchmarking of different SLS/SLM processes as Rapid Manufacturing techniques , 2005 .

[2]  M. F. Zaeh,et al.  Thermography for Monitoring the Selective Laser Melting Process , 2012 .

[3]  S. Gold,et al.  In-process sensing in selective laser melting (SLM) additive manufacturing , 2016, Integrating Materials and Manufacturing Innovation.

[4]  Christopher J. Sutcliffe,et al.  Selective laser melting of aluminium components , 2011 .

[5]  Bülent Sankur,et al.  Survey over image thresholding techniques and quantitative performance evaluation , 2004, J. Electronic Imaging.

[6]  Matti Pietikäinen,et al.  Adaptive document image binarization , 2000, Pattern Recognit..

[7]  Ferdinand van der Heijden,et al.  Efficient adaptive density estimation per image pixel for the task of background subtraction , 2006, Pattern Recognit. Lett..

[8]  T. W. Ridler,et al.  Picture thresholding using an iterative selection method. , 1978 .

[9]  A. Uriondo,et al.  The present and future of additive manufacturing in the aerospace sector: A review of important aspects , 2015 .

[10]  Tim J. Ellis,et al.  Image Difference Threshold Strategies and Shadow Detection , 1995, BMVC.

[11]  Matteo Pacher,et al.  Real-Time Observation of Melt Pool in Selective Laser Melting: Spatial, Temporal, and Wavelength Resolution Criteria , 2020, IEEE Transactions on Instrumentation and Measurement.

[12]  Jean-Pierre Kruth,et al.  In situ quality control of the selective laser melting process using a high-speed, real-time melt pool monitoring system , 2014 .

[13]  Richard J. Williams,et al.  In situ thermography for laser powder bed fusion: Effects of layer temperature on porosity, microstructure and mechanical properties , 2019 .

[14]  Yusheng Shi,et al.  Differences in microstructure and properties between selective laser melting and traditional manufacturing for fabrication of metal parts: A review , 2015 .

[15]  Robert Hudec,et al.  Comparison of Background Subtraction Methods on Near Infra-Red Spectrum Video Sequences☆ , 2017 .

[16]  Bianca Maria Colosimo,et al.  In situ monitoring of selective laser melting of zinc powder via infrared imaging of the process plume , 2018 .

[17]  Dan Xu,et al.  Background Subtraction Using Local SVD Binary Pattern , 2016, 2016 IEEE Conference on Computer Vision and Pattern Recognition Workshops (CVPRW).

[18]  J. Tomas,et al.  A deep learning-based model for defect detection in laser-powder bed fusion using in-situ thermographic monitoring , 2020, Progress in Additive Manufacturing.

[19]  D. Lu,et al.  Change detection techniques , 2004 .

[20]  Bianca Maria Colosimo,et al.  A statistical learning method for image-based monitoring of the plume signature in laser powder bed fusion , 2019, Robotics and Computer-Integrated Manufacturing.

[21]  Olivier Rigo,et al.  In Situ Monitoring Systems of The SLM Process: On the Need to Develop Machine Learning Models for Data Processing , 2020, Crystals.

[22]  Kari Pulli,et al.  Real-time computer vision with OpenCV , 2012, Commun. ACM.

[23]  A. Bandyopadhyay,et al.  Additive manufacturing: scientific and technological challenges, market uptake and opportunities , 2017 .

[24]  Nazri Mohd Nawi,et al.  The Effect of Data Pre-processing on Optimized Training of Artificial Neural Networks , 2013 .

[25]  Andrey V. Gusarov,et al.  Single track formation in selective laser melting of metal powders , 2010 .

[26]  P. KaewTrakulPong,et al.  An Improved Adaptive Background Mixture Model for Real-time Tracking with Shadow Detection , 2002 .

[27]  Kenneth Y. Goldberg,et al.  Visual tracking of human visitors under variable-lighting conditions for a responsive audio art installation , 2012, 2012 American Control Conference (ACC).

[28]  Dimitris Kanellopoulos,et al.  Data Preprocessing for Supervised Leaning , 2007 .

[29]  Paul L. Rosin,et al.  Evaluation of global image thresholding for change detection , 2003, Pattern Recognit. Lett..

[30]  Tsuyoshi Murata,et al.  {m , 1934, ACML.

[31]  G. Zack,et al.  Automatic measurement of sister chromatid exchange frequency. , 1977, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society.

[32]  Ping Jiang,et al.  Comparative Evaluation of Background Subtraction Algorithms in Remote Scene Videos Captured by MWIR Sensors , 2017, Sensors.

[33]  C. H. Li,et al.  An iterative algorithm for minimum cross entropy thresholding , 1998, Pattern Recognit. Lett..

[34]  Thierry Bouwmans,et al.  Traditional and recent approaches in background modeling for foreground detection: An overview , 2014, Comput. Sci. Rev..

[35]  Yu-Lung Lo,et al.  Optimized hatch space selection in double-scanning track selective laser melting process , 2019, The International Journal of Advanced Manufacturing Technology.

[36]  I. Yadroitsava,et al.  Factor analysis of selective laser melting process parameters and geometrical characteristics of synthesized single tracks , 2012 .

[37]  Shyang Chang,et al.  A new criterion for automatic multilevel thresholding , 1995, IEEE Trans. Image Process..

[38]  P. Fox,et al.  The effect of hatch angle rotation on parts manufactured using selective laser melting , 2019, Rapid Prototyping Journal.

[39]  Johan Potgieter,et al.  A comparison of traditional manufacturing vs additive manufacturing, the best method for the job , 2019, Procedia Manufacturing.

[40]  Ufuk Topcu,et al.  Graph Temporal Logic Inference for Classification and Identification , 2019, 2019 IEEE 58th Conference on Decision and Control (CDC).

[41]  Michael F. Zaeh,et al.  Layerwise Monitoring of the Selective Laser Melting Process by Thermography , 2014 .

[42]  Emmanuelle Gouillart,et al.  scikit-image: image processing in Python , 2014, PeerJ.

[43]  N. Otsu A threshold selection method from gray level histograms , 1979 .

[44]  Antoine Vacavant,et al.  A comprehensive review of background subtraction algorithms evaluated with synthetic and real videos , 2014, Comput. Vis. Image Underst..

[45]  B. Colosimo,et al.  Process defects and in situ monitoring methods in metal powder bed fusion: a review , 2017 .

[46]  Z. Zivkovic Improved adaptive Gaussian mixture model for background subtraction , 2004, ICPR 2004.

[47]  Changmeng Liu,et al.  Parameter optimization for Ti-47Al-2Cr-2Nb in selective laser melting based on geometric characteristics of single scan tracks , 2017 .

[48]  A. Kromm,et al.  Effect of hatch length on the development of microstructure, texture and residual stresses in selective laser melted superalloy Inconel 718 , 2017 .

[49]  Kunpeng Zhu,et al.  The investigation of plume and spatter signatures on melted states in selective laser melting , 2019, Optics & Laser Technology.

[51]  K. Jarrod Millman,et al.  Array programming with NumPy , 2020, Nat..

[52]  G. Tapia,et al.  A Review on Process Monitoring and Control in Metal-Based Additive Manufacturing , 2014 .

[53]  Badrinath Roysam,et al.  Image change detection algorithms: a systematic survey , 2005, IEEE Transactions on Image Processing.

[54]  Richard Leach,et al.  Review of in-situ process monitoring and in-situ metrology for metal additive manufacturing , 2016 .

[55]  Geok Soon Hong,et al.  In-situ monitoring of laser-based PBF via off-axis vision and image processing approaches , 2019, Additive Manufacturing.

[56]  Thierry Bouwmans,et al.  Background Modeling and Foreground Detection for Video Surveillance , 2014 .