Research Of Dispensing System Based On Three Dimensional Motion Platform

The cost of microelectronic packaging has gradually become the main source of cost in the process of microeletronics manufacturing. How to carry out fast and accurate microelectronic packaging has become an urgent problem to be solved. The method that traditional dispensing equipment used is show and work, which is complicated and does not meet the needs of modern production. In this paper, based on the requirements of modern semiconductor component mounting, we design the dispensing system based on three dimensional motion platform.According to the fluid dispensing technology, we designed the arrangement of the motion control platform, including the structrue of dispensing platfrom, hardware, and dispensing software. For the design of structure, we mainly designed the Z axis motion system. For the design of hardware, we mainly developed the motion control card and its outside interface. The design of software is mainly for the design of PC control interface, as well as the control logic and communication protocol.We research on the calibration method of vision system based on the dispensing platform. We calibrated the internal parameters of camera according to the MATLAB algorithm, and obtained the relationship between world coordinate system and image coordinate system. In this paper, we make derivation of hand-eye calibration of the motion platform, and established the hand-eye calibration algorithm based on linear error compensation. Finally we give the hand-eye result and analysis the error.Based on the PCB workpiece of dispensing, we designed the vision positioning plan of its feature points, mainly include the image preprocessing and the segmentation.As to the image preprocessing, we compared and analysis several ways of image filtering and image enhancement algorithm. As to the image segmentation, we do research on the Otsu and maximum entropy algorithm. Finally we obtain the best method of vision positioning based motion platform. We also use PSO algorithm to make optimization of image segmentationIn this paper, we builds up the three dimensional dispensing motion control platform, and completed the positioning of PCB image characteristic points through visual system, and finished dispensing task. Through experiments, we analysis different dispensing accuracy of different dispensing task, and present the numerical result.Experiment have proved that the dispensing motion control platform has good dispensing performance and guiding significance for dispensing and fluid research as well as equipment development.