Technologies In High-speed Online Detection Of Surface Quality Based On Machine Vision

The quality of workpiece surface is an important part of the workpiece quality, which providesan important guarantee for the value of workpiece. Methods used for the detection of workpiecesurface quality mainly depend on low efficiency of detection such as artificial. As a noninvasive,high precision and high efficiency of modern testing means, machine vision detection technologyplays a huge role in the field of high-speed detection. Therefore, this paper has a great significanceto quality of workpiece surface online detection based on machine vision.This paper puts focus on the key technology of high speed online detection of quality ofworkpiece surface based on machine vision. The main research contents are as follows:1. The research for high-speed online detection method based on machine vision. A method forhigh speed online detection of quality of workpiece surface based on machine vision was produced.The key technology of high-speed online detection method was studied, mainly included detectionaccuracy, field size, efficiency, motion blur and analysis of workpiece positioning. A vibrationcompensation method was used to compensate the error caused by the vibration and improved theprecision of size measurement. The detection method acquiring the images of motion workpiece notonly provided the clear and accurate positioning images, but also improved the precision of thedetection of general quality of workpiece surface. The method offered a reference value for thegeneral quality of workpiece surface detection.2. The design of high speed online detection system based on machine vision. A high-speedonline detection system based on machine vision was designed. The function of the system includedthe workpiece feeding, image acquisition, image processing and the carved material. The hardware,software and auxiliary device part of the system were designed. The hardware of the systemincluded workpiece position detection based on plane array cameras, high-speed image acquisition,vibration error compensation and other parts. The workpiece position was detected by the highaccuracy time delay method. The vibration error compensation was accomplished by correcting themagnification of optical system and controlling the motion blur by reducing the exposure time.Meanwhile the work sequence of high-speed online detection was designed. Software part of thewhole test system was designed for driving the hardware modules to work properly, completing theprocessing and analysis of the workpiece surface quality according to the testing process. Theauxiliary device part mainly included feeding mechanism, design of the directional guide anddesign of the take part. The high precision positioning module, vibration error compensation module and high-speed image acquisition module were designed, which can effectively improve theprecision of workpiece size detection and surface quality detection.3. A relevant experiment was designed. The experimental environment was analyzed. The highspeed camera frame rate experiment, experiment on flash exposure synchronicity and experimenton asynchronous reset signal was completed, in order to verify the stability of collected signal. Theresults for the measurement results of the same workpiece were stable and reliable. In this paper, themethod of online detection can satisfy the needs of accuracy of workpiece surface detection andefficiency of high-speed online detection system, and complete the workpiece surface quality ofhigh speed, real-time, online, non-contact measurement as well. The precision of measurement was0.05mm, and the efficiency was20pieces in a second.