Key Technologies Of Controlling Platform Of Mounter Based On Vision Guidance

Surface Mount Technology(SMT)is the precision manufacturing technology which installs a variety of components unto the printed circuit board through various apparatus.As the most significant equipment in the SMT production line,the mounter fully integrates the high-tech multidisciplinary achievements in many fields,such as light electromechanical integration,precision technology,information communication and computer network control,and the performance quality directly affects the efficiency and capacity of the entire SMT production line.However,due to the late start of research on the mounter at home,the mounters used in the domestic large-and-medium-sized SMT production line are imported from other countries currently.However,due to the high cost of imported mounters,the cutting-edge technologies involved in the mounters are not available for China.Therefore,it is greatly crucial to develop domestic autonomous grand of the mounters with stable performance and low cost,which exerts huge and profound influence on the electronic manufacturing.Based on the aforementioned questions and combined with the development project of the mounting equipment used in the enterprise,the key technologies of controlling platform of the mounter based on vision guidance are carried out in this paper,and the main work is as follows:(1)On the basis of the demand analysis of the mounter,the performance indexes of mounting speed,mounting precision and range of the surface mounted devices(SMD)are designed.According to the performance indexes of the mounter and the characteristics of the controlling platform,the structure and work flow of the motion platform are determined,and the controlling scheme and the vision guidance scheme of the controlling platform are determined.(2)Aiming at the overall scheme of the controlling platform of the mounter,the motion controlling platform such as suction nozzle pick-up pneumatic system,AC servo controlling platform,PCB transmission mechanism and on-the-fly vision system are built.Based on the controlling scheme of on-the-fly vision,the method which utilizes the output signal of the high speed position comparator of the motion controlling card as triggering source to trigger the camera to take pictures is put forward,which can realize the precise location control of X and Y axes during dynamic image collection.(3)A method which analyzes the original coordinate data of PCB from the Gerber file of PCB is proposed.Based on this method,a program module which can quickly extract the coordinates of all the components is contrived.and the program module is written as a dynamic link library to achieve online and offline programming capabilities.At the same time,a mathematical model of 2D vision guidance system was set up on the controlling platform,and the vision guidance scheme of the mounter is realized through the calibration of 2D vision guidance system and the robotic hand-eye calibration.(4)Aiming at the user-machine interface and the underlying software of controlling platform of the mounter,the system software of the whole controlling platform is designed and developed.The complete controlling platform of the mounter is constructed by combining the software module and the hardware module.The repetitive positioning accuracy of X and Y axes,the stability of collecting images of on-the-fly vision system and the actual placement effect are experimentally analyzed to verify that the designed controlling platform of the mounter meets the performance requirements.