Research Of Data Extraction For Spatial Cutting Trajectory Based On Re-development Of UG

With the CAD/CAM technology widely used in industry, CNC programming technologyhas got more and more attention in the current CAD/CAM systems, it has improved the levelof industrial automation, and has played an important role in improving precision andreducing production cycles. Graphics-based CNC programming system is more and moreimportant in industry. In order to solve the problems such as complex trajectory, this papertook tablet groove and cylinder pipes crossing model as the examples, which are usedcommonly in industry, and researched on the automatic programming system for extractingthe spatial cutting trajectory data.This paper firstly extracts data from the two-dimensional graphics CNC file of the DXFformat, which is exported by UG. With analyzing DXF format files of two-dimensionalgraphics and programming, the data interface of the DXF files is created in Visual C++6.0platform using the object-oriented programming method and the graphical entities data inDXF file can be extracted through this interface. A contour recognition algorithm is proposedfor contour-ordering, on this basis, the groove graphics can be extracted orderly, and theinterpolated groove data is used to generate the cutting trajectory sequences for robot. Thesystem makes a simulation to ensure data is correct, and then converts the data into theimplementation pulses and sent it to the cutting device for cutting task.Combined with the characteristics of the three-dimensional parts, solving the spatialtrajectory problem on the surface entity by researching on the automatic programming systemis the main objective of this paper. Based on the Visual C++6.0software platform, the datathat required by CNC machining environment is extracted under UG by programming usingthe second developing tool named UG/Open API that the interface between UG and VC++6.0.The overall structure design was based on the functional requirements of the system, and thispaper introduced the function module of the system and analyzed the key technologies of eachmodule in detail.In this system, it can implement to import the entity model modeled by CAD softwareinto UG environment, and operate edges and faces of solid model objects by programmingwith UG/Open API functions for extracting three-dimensional coordinate figures and thenormal vector. Then it calculates the dihedral angle of each point on the curve of solid surface,and gets the spatial cutting trajectory. Finally, in order to compare the extracted informationdata with the theoretical data, this paper verified the correctness of the system. The proposed method is versatile and has high accuracy.