Research On 3D Print Measurement And Control Method Based On FFOCT

In recent years, witnessing the rapid development of 3D printing technology and the appearance of MakerBot desktop printer, people learn more and more about rapid prototyping technology. The current desktop print accuracy is about 0.1 mm, while that of the industrial printers has reached 13um. The price of the latter, however, is thousands of times higher than that of the former. Thus, reducing the cost and improving the printing precision has become the focus of studies on 3D printing technology. Researchers at home and abroad have contacted a lot of studies in this field.To improve the accuracy of 3D printer, these studies mainly focus on improving the accuracy of the mechanical system and the printing material forming process. However,there is few studies concern the method of adding the three-dimensional test system to enhance the overall accuracy of the printer while keeping the accuracy of the mechanical system. This method not only provides a low-cost solution to improving the accuracy of 3D printer, but also resolves the conflict between the accuracy and the cost of 3D printer batter.In this study, a 3D test system is designed based on Full Field Optical Coherence Tomography(FFOCT) technology to improve the accuracy of the 3D printer.In detail, 1) the mechanical structure of the light path and the 3D imaging algorithm is designed, the texture filter and curve fitting is used to calculate the range image and the Gauss filter is used to reduce the noise; 2) the lens and the response of the camera is calibrated; and 3) the software of the test system is designed , which can realize the camera calibration, mobile platform control, camera setting and image processing. Finally, based on the designed 3D test system, coin imaging test and gauge block accuracy test is conducted,the result of which shows that the test accuracy of the imaging system can meet the design requirements.The 3D system designed in this study is based on FFOCT, which requires a higher light path adjusting accuracy. A “cross filter" adjusting method is proposed , with low cost and better adjusting effect, successfully shortens the time for light path adjustment.