Automated Rebar Spacing Measurement in Mixed Reality Using RebarSAM and Monocular Depth Estimation

ARMIS is a fully automated mixed reality system on HoloLens 2 for near real-time, in-situ inspection of multi-layer rebar spacing. It combines RebarSAM, a geometry-aware adaptation of SAM 3, with layer separation based on Depth Anything V3, checks each measured spacing against the specified tolerance, and shows pass or fail results as a holographic overlay. It was validated in live rebar inspection with Expand Construction Pte Ltd, main contractor for the NS Square project at The Float @ Marina Bay.

@unpublished{zhangautomated,
  title     = {Automated Rebar Spacing Measurement in Mixed Reality Using RebarSAM and Monocular Depth Estimation},
  author    = {Zhang, Z. and Yang, X. and Fu, Y. and Ghosh Mondal, T.},
  note      = {Under review at Automation in Construction}
}

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   Zhang, Z., Ghosh Mondal, T., Yang, X., and Fu, Y.*

   ASCE Journal of Construction Engineering and Management, 152(10), 03126011 (2026). DOI

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   Automated Noncontact Geometric Quality Assessment of Building Elements Integrating Mixed Reality, Depth Sensing, and Vision Foundation Model

   Zhang, Z., Ghosh Mondal, T., Yang, X., and Fu, Y.*

   ASCE Journal of Computing in Civil Engineering, 40(1), 04025130 (2026). DOI

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   Gaze-Driven Mixed Reality for Dimensional Quality Assessment of Timber Components Using a Few-Shot RGB-D Vision Foundation Model

   Zhang, Z., Yang, X., Fu, Y.*, and Ghosh Mondal, T.

   Advanced Engineering Informatics, 77, 105186 (2027). DOI

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   Human-in-the-Loop Rebar Inspection: Integrating Vision Foundation Model with Mixed Reality for Construction Quality Assurance

   Zhang, Z.*, Ghosh Mondal, T., and Yang, X.

   2026 IEEE International Conference on Human-Machine Systems (ICHMS), Singapore, 452–457 (2026). DOI