A novel one-body dual laser profile based vibration compensation in 3D scanning

Abstract

Recently, the 3D laser profile scanner has often been used for the precise measurement of 3D surface information (object surface) such as height, area, and slope. However, a difficulty encountered with the conventional laser scanning method is that it cannot compensate for the errors resulting from vibration, so the scanned object should be measured in a fixed (immobile) state. In this paper, we propose a novel dual laser profile method and its error compensation algorithm to compensate for vertical vibration, even with a moving object. In order to remove errors caused by vibration, the proposed system projects two laser profiles onto the surface, such that the projected position overlaps the one with the previous position. With the overlapped position, the height difference between the measured objects is used to calculate the vibration errors. To generate two laser profiles simultaneously, we present a novel approach for generating two laser profiles from one laser-emitting source (a one-body dual line laser using a triangular structured blazed grating reflector). By exploiting the one-body dual line laser and error compensation algorithm, the proposed 3D laser profile scanner system achieves an error reduction of about 96.3% in the root mean square error (RMSE), compared to the conventional approach. (C) 2018 Elsevier Ltd. All rights reserved.