Development of a new laser triangulation system based on an optical frame of reference

Abstract

In this paper a new triangulation‐based laser scanner is presented which has a simple, yet strong, flexible and low‐cost structure. A digital camera and three laser line projectors are the main components of the system. One of the laser projectors is positioned vertically, while the other two are horizontal. The former scans the object, whereas the latter two establish an optical frame which is used, in part, to define the plane containing the vertical laser projector at each step of scanning. At each step, an image is taken which includes the object along with the projected laser lines. By intersecting the vertical and horizontal lines a couple of points are formed which, along with the calibration information of the system, enable the extraction of the object coordinates. Results of the tests carried out show that by using an optical frame of this nature, the process of scanning is greatly facilitated. That is, the scanner can easily be used to scan objects of different size and dimensions. Within the current configuration, the system enables measurements with an accuracy of 1/1600. Also, as the system has a rigorous basis, its accuracy can be increased if improved hardware is provided.

Modeling and Calibration of a Novel One-Mirror Galvanometric Laser Scanner

“…The laser stripe sensor can also be fixed at the end of the coordinate measuring machine to form a highly accurate laser scanner [ 8 ]; however, the coordinate measuring machine is not suitable for being installed on the production line. There is also another form of laser scanner where the position of the projector with respect to the camera coordinate system can be determined via additional reference frame [ 9 , 10 ] or physical constraint [ 11 , 12 ]. Ren [ 13 , 14 ] proposed a linear laser scanner via mounting the laser stripe sensor to a linear rail and the linear rail takes the vision sensor to perform linear scanning.…”

Plane-constraint-based calibration method for a galvanometric laser scanner

“…5. Transform the image coordinates of the control points to the local WCS using both camera intrinsic parameters and extrinsic parameters according to equation (13). 6.…”

“…The laser stripe vision sensor can also be fixed to the end of a coordinate measuring machine to form a highly accurate laser scanner; 12 however, the coordinate measuring machine is not suitable to install on the production line. There is another form of laser scanner where the position of the projector with respect to the camera coordinate system (CCS) can be determined by additional reference frames 13,14 or physical constraints. 15,16 Ren et al 17,18 proposed a linear laser scanner by mounting the laser stripe vision sensor to a linear rail; the linear rail moves the vision sensor to perform linear scanning.…”

Development of a new dual‐pattern fringe projection scanner

“…For many years, systems and/or algorithms have been developed to deal with either a broader variety of applications or to reduce the uncertainties associated with some previously established techniques. In general, a range sensor uses either laser (Abzal et al., ) or white light (Salvi et al., ) to reconstruct the 3D model of an object. Based on an excellent review by Blais (), range sensors can be grouped into single‐point, slit, time‐of‐flight, projection and moiré classes.…”