In the glue coating process is more likely to lead to the emergence of many enterprise quality control defects, such as leakage, broken glue, glue coating excess. Conventional management tools can rely on China's artificial visual and caliper measurements, there are not too many uncertainty factors, and can not be detected through real-time online, and it is difficult to realize the trajectory of China's robotic arm observation, unable to determine the root cause of a problem. Compared with artificial intelligence detection, machine vision-based detection technology with high efficiency,vision inspection systems high accuracy, objectivity and other characteristics, can significantly improve the quality and efficiency of glue.
Second, testing needs
Common testing needs include glue width, glue height and breakage, multi-glue test, some manufacturers also pay attention to glue trajectory anomalies, positional deviation detection (reverse robot abnormalities, etc.). To an automotive assembly plant windshield gluing test as an example.
Glue height 8mm, glue width 12mm, the center of the glue seam from the edge of the hood 12mm, precision is not less than 1mm;
The complete process beat is 30s;
On-line real-time analysis and detection,automotive consulting services record the location of defects such as glue breakage and leakage, and output whether there is any abnormality in the gluing trajectory data.
Third, the detection program
There are three main automatic testing methods based on machine vision.
1, 2D multi-meter
Glue gun around the integration of multiple 2D surface array camera, compact design, suitable for narrow production environment, fast detection speed, can realize 360 ° glue width, position, continuity detection. Integrated complementary light system supports different exposure and parameter settings, can adapt to a variety of ambient light detection scenarios, adaptability.
2.3D high-speed contour measuring instrument
Considering that the simple 2D face array system can not obtain the information of the glue, and the glue strip is usually a narrow band, which is suitable for the application scenario of line laser measuring instrument. Therefore, the contour measuring instrument can be integrated behind the glue gun at the end of the robotic arm to follow the gluing trajectory of the robotic arm to complete the online measurement, so as to detect the gluing width, gluing height, position and continuity (but theoretically there is a blind zone at the end and corners). Considering the high gluing speed, generally up to 400~1000mm/s, the sampling period of the measuring instrument has high requirements.
3, 3D multi-line laser combination
Considering the blind spot of a single contour measuring instrument there is a problem in the configuration of the glue gun around the management of multiple 3D line laser technology combination can be effectively avoided, can be obtained without a dead angle of the shape of the coating glue, to achieve the precise analysis of the glue width, glue height, position and continuity of the online education measurement.
Most of the traditional coating quality inspection is offline inspection, taking up additional production time, and vision-based coating quality inspection program in the accurate acquisition of coating quality information on the basis of the realization of the coating quality of the online inspection, you can verify the robot trajectory and other issues, and greatly improve the stability and detection efficiency.