|
Fringe projection profilometry (FPP) is widely used because of its many advantages, such as high accuracy, no-scanning properties, and full-field measurement. When fringe projection profilometry is employed, system calibration is one of the vital procedures. The accuracy of system calibration directly affects the quality of measurement results. The traditional calibration methods of measurement system include several calibration contents, like verticality, parallelism and the calibration of system geometric parameters. Aiming at the difficulties of them and the complexity of operation and adjustment process, this paper puts forward corresponding improvements. The calibration of verticality and parallelism uses checkerboard, which eliminates the requirements of hardware preparation for calibration such as standard parts. In the calibration of system parameters, it is not necessary to know the specific value of each parameter, and the parameters can be divided into two parts for calibration. The validity and practicability of the proposed methods have been proved by experiments. We take the ceramic step shape standard part as the tested object. After calibration by the above methods, the maximum measurement error of the fringe projection profilometry measurement system is -0.1400mm and the maximum standard deviation is 0.7251mm.
|
