Specular surfaces 3D measurement method based on the fusion of mono-phase measuring deflectometry and active tactile detection

Abstract

Specular surfaces present significant challenges for traditional 3D vision measurement techniques due to their strictly reflective properties. This paper proposes an innovative 3D reconstruction method for specular surfaces that combines monocular phase measuring deflectometry with robot active tactile detection. Mono-PMD captures surface gradient data through phase-shift patterns, while tactile sensors provide sparse, precise absolute height information. By fusing these data sources, the proposed method addresses PMD’s gradient-height ambiguity and the limited data density of tactile sensing, achieving accurate reconstruction of specular surfaces. Experimental results show that this method reduces RMS error by 34.6 % compared to the conventional PMD methods, achieving RMS errors as low as 0.0084 mm after radius fitting on concave and convex mirrors with radii of 100 mm and 200 mm. This fusion approach effectively eliminates the need for imaging agents, streamlining measurement processes, and enabling faster, more precise 3D reconstruction and positioning. The proposed method offers robust technical support for future interactions between robotic systems and high-reflective specular objects.