A flexible large-size shape-measurement system

A flexible large-size shape-measurement system, based on the triangulation measurement principle, achieved high precision and non-contacting measurements of large shapes. The system overcomes the shortcomings of three-coordinate measurement machines. In this system, the measuring instruments can be set according to measured pieces. A high-precision electronic theodolite, used as an angle sensor, is a pre-condition for measurement precision. The key point for wide use of this system is setting up the relationship between the coordinates of the sampled points and the measured parameter. The measurement precision is based on a reasonable arrangement of the measuring instruments, and solving for the relative parameters. The computed position-measurement accuracy of the system is 0.1 mm. The system has been applied successfully to the measurement of large curved surfaces.