Improving depth measurement of textured surface by a boundary estimator for structured light patterns

In home service robot applications, robots often deal with textured objects. The variation of surface's reflectivity may decrease the accuracy of depth measurement of structured light 3D camera. In this paper, we propose a new method to correct the boundary of structured light pattern in order to increase the accuracy of depth measurement. The algorithm first estimates the reflection index of the surface. The light stripe is deconvoluted to remove the smooth effect of the camera lens. Finally, the edge is normalised by the reflection index, and the boundary is estimated from the intersection between the corrected versions of the edge and its inverse. The experimental results show that with the proposed boundary estimator, there are significant improvements in term of surface smoothness of textured objects.