Design And Implementing Of The Visual Location System In HZHDFC Packing Equipment

Packaging equipment is the core of IC packaging industry; its performance directlyaffects the processing quality and production efficiency in IC packing industry. Machinevision technology is one of the key technologies to ensure that packaging equipment withhigh precision, high efficiency. Currently domestic research about machine vision technologyis still under development. With respect to the visual processing accuracy, visual detectionspeed and stability there is a large gap in foreign countries. In this paper, we studied visualpositioning system based on the HZHDFC packaging equipment as research platform ourresearch team developed independently.For chips packed by HZHDFC equipment having characteristics of multi-pin,intensive-IO, small bump pitch, we designed a vision positioning system which combines therough determination system with accurate visual determination system. The roughdetermination system uses the on-the-fly technology which can acquire images in the chiptransfer process, in order to locate the chip and the substrate detection area quickly. Thehigh-resolution camera further locate the chip and the substrate based on the result of therough determination. The visual system which applied to HZHDFC packaging equipment canlocate the chip and substrate quickly and accurately.We proposed an image positioning algorithm based on Harris corner detection algorithm,which uses two-dimensional scanning lines to automatically filling enclosed area thatimproves quality of the initial image. The algorithm tracks corners fast through image scalingand then determines the line extraction area. We calculate the precise location information ofthe corner in this area by Hough transform. The algorithm realizes locating the position ofobject fast and accurately that cannot be seen completely. Offline experimental tests show thatcomparing with geometric feature matching algorithm, the algorithm has higher robustnessand its positioning accuracy can reach±5μm.Based on the system working requirements, we completed the software requirementsanalysis, software system design (including multi-threaded programming, module actionplanning process, important function interfaces packaging, user interface design, etc.). In thispaper, the design of the visual system was used in the HZHDFC packaging equipment. Theresult shows that the packaging equipment can run successfully, which verified the reliabilityof the vision system designed in this paper. We finished a processing test on the equipment;the test results show that the visual system can achieve±50μm accuracy on the device.