The Research And Development Of Workshop Auto Programming System For Milling Feature

With the popularity of modern CNC machines in the manufacturing industry,the programming efficiency in the processing workshop are getting plenty of attention.Low efficiency of the traditional CNC programming makes it harder for China-produced CNC system to compete in the marketplace.In order to improve the programming efficiency and the process integration capability of CNC system,this paper uses the HNC-8 system as a platform to apply the feature recognition technology into the CP system,and establishes a workshop automatic programming system for the milling feature.The main content is as follows:Since the integrated CP system of CNC system can not obtain the design information of the product components directly,this paper takes the STEP neutral file as input and designs the integral frame of the workshop automatic programming system for the milling feature with the feature recognition technology.By using the Intelligent Application Platform of the high-end HNC-848 CNC system,this paper puts forward the solution of NC integration to the programming system in Windows environment.In order to realize the data sharing and transfer between the CAD system and the programming system,this paper studies the information extraction of the STEP model by using the ROSE library.Then,it completes the three-dimensional model reconstruction by using OpenGL graphics display interface to provide the interactive definition for the feature recognition,as well as providing a visual environment for workshop-oriented programming.According to the fixed cycle process type supported by CNC system,a database of two5 D milling manufacturing feature is established.In order to meet the requirement of feature recognition,this paper adopts the rule-based automatic recognition and matching algorithm to realize the automation extraction of the key geometric parameters of each feature in the part.In order to further improve the efficiency of conversational programming,this paper designs a convenient process planning and builds a comprehensive data model for processing plan.At the same time,the process knowledge base has been designed with configuration file to implement the automatic of the step process parameter editing.With an analysis and some researches of fixed cycle instruction and parameterization tool path,the generation technique implementation based on the parametric template of the NC program has been proposed.In order to satisfy the processing requirements of more part features,this paper has put forward a technique implementation of featurebased processing templates from the aspect of software architecture.Based on the above researches,the automatic programming prototype system for the milling feature is developed by using tools such as VS2013,Qt5.7 and Rose library.Takin g a simple part model as an example,it completes the whole process from STEP file input to NC program output and to simulation processing which verifies the feasibility of the de sign scheme and the efficiency of NC workshop programming.