The Research On The Key Technology Of Laser Marking System For Casting Wood Model

The automatic identification of materials is the basis for enterprises to realize information management.Casting wood mold is an important mold for metal casting production,which is affected by factors such as materials,shape,and environment,cuasing the difficulities in achieving automatic identification.Laser marking is a direct part marking technology(Direct Part Marking,DPM)that has emerged in recent years.Compared with other technologies,laser marking technology has the advantages of non-contact,no consumables,low power consumption,low cost and so on,having become the preferred technology for material marking in many industries.There are many problems in the application of laser marking to casting wood molds,including: the relatively large volume and numerous styles of the casting wood mold,the difficulity in positioning of the laser marking plane,and the difficulity in the implementation of the laser autofocus mechanism;The laser marking has many control parameters,and different combinations of parameters having a great impact on the quality of the marking image is difficult to select the process parameters reasonably.Aiming at the above problems,this thesis studies the key technology of laser marking of cast wood molds and develops a laser automatic marking platform based on mobile robots.The main contents of the thesis include:(1)The application scenarios of wood mold identification is analyzed,the main difficulties of laser marking of cast wooden molds is determined,and the needs of system development is analyzed.(2)The mobile robot is proposed as the driving platform for the laser light path.The overall design scheme of the hardware is designed.The 3D design and assembly simulation are completed.The core components are subjected to static and modal analysis to verify the design parameters.(3)The laser focusing control system architecture is determined,and a laser rangefinder is designed based one plane positioning solution.The laser rangefinder is used to obtain the coordinate space of the marking plane to form a data set of the marked plane,and then a 3D fitting of the marked plane is realized using a improved RANSAC algorithm(Random Sample Consensus Algorithm).(4)The influence of laser marking parameters on the laser imaging effect of wood molds is revealed.A mathematical model for the gray scale and laser marking parameters of laser marking images on the surface of casting wood molds is established based on the process test of laser marking wood molds,and it provides a basis for the reasonable selection of laser control parameters.(5)A laser marking data management system based on the data environment of the enterprise application site is designed and developed,which includs laser marking software based on C/S architecture,inventory management software based on Android,and the decision-making platform of the marking data management system based on B/S architecture.On the one hand,it provides marking information for laser marking.On the other hand,it provides feedbacks on-site data for the MES system.Thereby the management efficiency of the enterprise is improved.The results of this thesis have been put into practical use by a group company in Northwest China and have achieved the expected results and goals.