Research On The System Of Laser Marking Galvanometer Based On Automatic Visual Positioning

Laser marking system is being developed towards the direction of intelligentization,miniaturization and integration, along with the development of Intelligent Industry and the continuous inter-disciplinary corporation. The introduction of industrial camera and automatic positioning embedded system helps equip the traditional optical vibration mirror with “eyes”, leading to a more accurate and efficient laser marking system. It also saves a large amount of labour cost and reduces the errors brought by manual manipulation, as well as making the marking system adapt well to a wide variety of extreme conditions. This dissertation reports the investigation and design of a solution to the integration of visual positioning and laser marking system with industrial camera added. The following areas are covered:(1) Both hard- and soft-ware of visual positioning vibration mirror system in the Chinese market were analysed, after which a new fully functional system was proposed according to their current shortcomings.(2) Based on practical usage, the characteristics of hardware needed in different stages were analysed and compared. We summarised the criteria for selection and set-up of different equipments during practical use.(3) The theoretical investigation into the visual positioning algorithm and its implementation. We proposed here a novel algorithm for the matching between visual coordinates and laser vibration mirror coordinates, which is believed to be more appropriate for the practical use of laser marking. In addition, the algorithm for contour extraction of target workpiece was studied and implemented in Opencv.(4) A complete laser marking system with visual positioning integrated was constructed successfully. This process mainly included the software-hardware matching, comparative analysis of multiple set-ups, as well as the efficiency analysis of the whole system.The critical techniques involved in this dissertation includes: the matching between pixelcoordinates and vibration mirror coordinates; pattern recognition and contour extraction; the integration of camera, lens and light source, together with the parameter selection; timeliness of processing algorithm.