基于SFS的浮雕数控自动编程方法研究与实现

发布时间：2018-07-14 14:47

【摘要】：浮雕产品被广泛应用于家具制造、广告装潢等行业中。随着数控技术的发展，数控加工已成为浮雕加工的主要方式，其中数控编程是浮雕数控加工过程中的重要技术。现行主流数控编程需要经验丰富的编程工程师的参与，且多采用专业的CAD/CAM软件进行辅助设计。对于多数浮雕加工中小型企业来说，这样的方式有着成本高、效率低的缺点。因此，这些企业迫切需要一种低成本、高效率且拥有自主产权的数控自动编程方法，来提升自身的市场竞争力。本论文的基于SFS的浮雕数控自动编程方法，能够满足上述中小型企业的需求。该方法通过对实物进行：图像采集（或者输入灰度艺术图）、预处理、浮雕三维重构和浮雕数控加工后置处理后，，可以得到通用的数控程序，从而加工出浮雕产品。本文完成该方法的流程设计并对每个步骤进行理论分析和软件设计，其中重点研究了三个方面内容：浮雕图像预处理、三维建模和数控编程后置处理。浮雕图像预处理方面，本文针对实际需求，应用坐标映射原理改进常规的加权灰度化方法，采用一种自适应中值滤波器对图像进行去噪处理，并通过设计相关软件和验证，证明其效果优于常规预处理方法。浮雕三维建模方面，本文在分析了引入SFS实现浮雕三维建模的原因，采用Oren-nayar光照模型描述实物形状与图像灰度的关系，并演算简化该模型后得到了光照方程，进而根据SFS线性化方法的思想推算出计算图像高度的迭代求解公式，最后设计相应软件，在180°范围内实现了实物的三维（2.5维）重构，通过仿真验证，证明了应用SFS进行三维重构的合理性。数控编程后置处理方面，根据一定的工艺参数以及刀具型号，采用往复式走刀方法，并对浮雕进行行高度轮廓拟合，按照HPGL指令格式设计实现了数控程序生成软件，得到了可以在数控雕刻机床上运行的数控程序。本文分别以实测实物图像以及灰度艺术图作为输入数据，得到了相应的数控程序，最终加工得到了与实物轮廓和纹理特征一致的、立体感强的、观赏性良好的浮雕成品，从而证明了本文的数控自动编程方法的有效性。
[Abstract]:Relief products are widely used in furniture manufacturing, advertising decoration and other industries. With the development of numerical control technology, numerical control machining has become the main way of relief machining, in which NC programming is an important technology in the process of relief NC machining. The current mainstream NC programming needs the participation of experienced programming engineers, and most of them use CAD / CAM software to assist design. For most small and medium-sized relief processing enterprises, this way has the disadvantages of high cost and low efficiency. Therefore, these enterprises urgently need a low cost, high efficiency and self-owned NC automatic programming method to improve their market competitiveness. The automatic programming method of relief NC based on SFS in this paper can meet the needs of the above small and medium enterprises. In this method, the general NC program can be obtained by image acquisition (or input grayscale art map), pre-processing, three-dimensional reconstruction of relief and post-processing of relief NC machining, and then the relief products can be processed. In this paper, the flow design of this method is completed, and the theoretical analysis and software design of each step are carried out. Among them, three aspects are emphatically studied: pre-processing of relief image, 3D modeling and post-processing of NC programming. In the aspect of pre-processing of relief image, this paper applies the coordinate mapping principle to improve the conventional weighted grayscale method, adopts an adaptive median filter to de-noise the image, and designs the relevant software and verification. It is proved that its effect is superior to that of conventional pretreatment method. In the aspect of 3D modeling of relief sculpture, this paper analyzes the reason of applying SFS to realize 3D modeling of relief, uses Oren-nayar illumination model to describe the relation between object shape and image grayscale, and calculates and simplifies the model to get the illumination equation. Then, according to the idea of SFS linearization method, the iterative solution formula for calculating the image height is deduced. At last, the corresponding software is designed, and the 3D (2.5 dimension) reconstruction of the object is realized in the range of 180 掳. The rationality of using SFS for 3D reconstruction is proved. In terms of post-processing of NC programming, according to certain technological parameters and cutting tool type, the reciprocating walking cutter method is adopted, and the line height contour fitting of relief carving is carried out, and the NC program generating software is designed and realized according to HPGL instruction format. The NC program which can be run on the CNC engraving machine is obtained. In this paper, the real object image and grayscale art map are used as input data respectively, and the corresponding numerical control program is obtained. Finally, the relief products which are consistent with the physical contour and texture features are obtained, which have a strong sense of three-dimensional and good appreciation. Thus, the validity of the NC automatic programming method in this paper is proved.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TG659

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