Research And Realization Of A CAM Software For Multiple Spindle Planar Woodworking Machining

The wood working industry of China faced a lot of problems such as lack ofcreativity, little technology involved, low level of automation, and low competitiveness.Increasing the percentage of numerical control equipments is the key to these problems.Wuhan Huazhong Numerical Control co.,ltd. developed HNC-3000five-axis numericalcontrol wood working milling machine. This machine meets the demands of woodworking industry. However, special computer aided manufacturing software is required tofulfill the capability of this equipment, and realize the fast, efficient and automaticoperation of this equipment.In this research, computer aided manufacturing software is developed based onAutoCAD. The Application Programming Interface used to carry out the extenddevelopment of AutoCAD is ObjectARX, and the development environment is VisualStudio C++6.0. The key algorithms developed during the development are described asfollows:Curves sorting algorithm: The curves in each layer of work space is disordered bothin sequence and direction, and they contain defects which add difficulties to the analyzingof the relation between curves. The algorithm sorts the curves according to the cuttingsequence, and also divides the curves into segments.NURBS curve discretization algorithm: the algorithms take the profile of the workpiece and available functions from ObjectARX into consideration. It is fast and robust,and interpolates relative fewer points at given tolerance.Multi-tool coordinated control algorithm: the algorithm coordinates the movementsof cutting tools. The cutting tools can have independent tool path. The algorithm alsoprocesses the cutter location file and generates manufacturing file.This software is specialized for HNC-3000five-axis NC milling machine. Afterimporting the engineering graphics of the work piece, the software divides the curves intogroups, and then sorts, patches up and offsets the curves to generation tool path for eachgroup. Then it plans the engagement and retracting tool path, checks collision, and carriesout the post-process for the tool path. At last it coordinates the movement of each cutting tools, converts the tool path file, and adds auxiliary commend to generate manufacturingfile.During the verification process, the software was able to generate manufacturing filesfor work pieces. The manufacturing files is high efficient, and the product obtained has agood surface quality. The performances of the software meet the requirements of thecustomer.