外文翻譯--基于細(xì)分曲面生成的三軸數(shù)控切削軌跡的研究-數(shù)控設(shè)計(jì)-資料下載頁(yè)
2025-05-12 07:21本頁(yè)面
【導(dǎo)讀】在本文中，我們提出數(shù)控切削軌跡生成細(xì)分曲面的方法和算法。狀曲面的細(xì)分曲面。一條軌跡示意圖，包括粗糙切削完成切割是發(fā)展的基礎(chǔ)上逐步。的LOD的細(xì)分曲面。為了完成切削，使用球頭磨坊，壓榨機(jī)和抵銷切削產(chǎn)生位置連絡(luò)放置的地方。我們執(zhí)行我們的方法和目前的加工結(jié)果。機(jī)械加工自由形態(tài)曲面在生產(chǎn)模具方面占據(jù)一個(gè)重要的角色。面模型被曲現(xiàn)為參數(shù)曲面小塊。CAD產(chǎn)生系統(tǒng)［2][6][7]。統(tǒng)不能自動(dòng)的解決這些問題，工程師必須用手改正。的數(shù)控資料這個(gè)嚴(yán)重的問題經(jīng)常影響產(chǎn)品的質(zhì)量。細(xì)分曲面的基本觀念是產(chǎn)生一個(gè)平滑曲面通過重復(fù)地細(xì)。另外，那細(xì)分曲面有特定的連續(xù)性，舉例來說，因?yàn)檫@些細(xì)分曲面在計(jì)算機(jī)直觀顯示的領(lǐng)域。一個(gè)原因是我們?nèi)匀徊恢朗欠窦?xì)分曲面適用于凸輪。這項(xiàng)研究的目的是為了通過細(xì)分曲面發(fā)展一個(gè)有效的數(shù)控通路形成法。擇環(huán)狀細(xì)分曲面［1］。同時(shí)新的頂點(diǎn)進(jìn)入邊緣之內(nèi)是被稱為奇數(shù)頂點(diǎn)。意思是覆蓋網(wǎng)孔完全覆蓋界限曲面。
【正文】 space is not so easy. Some part of the limit surface may e above the mesh even though all the vertices are above the surface. Such a part can be detected by checking the local convex hull of the control mesh. In order to solve this problem we used Jos Stam39。s evaluation method [4] to parametrically pute the points on the limit surface, as is the case with ordinary parametric surfaces. Firstly we evaluate a series of points along edges between two triangular faces as shown in . Then we judge if a sampled point is below the two neighbor triangles. When there are some points located above these triangles, we find the highest point, and calculate the distance (dmax ) from the highest point to the evaluated edge. In Fig. , we offset vertices to their new positions V using Eq. (), where N is the normal at the vertex. On the boundary, we cannot evaluate the points on the edge curve, thus only Fig. illustrates an example of this method. (a) shows the original mesh M0 in red color. (b) shows the M1 mesh (subdivide M0 once) in green color. Fig (c) shows the limit surface. Fig (d) shows both M1 mesh in green color and limit surface in red color. It can be seen that M1 mesh intersects with the limit surface, in other words, the green part is intersecting with the red part. Fig (e) shows the cover mesh generated from M1 with our method in blue color. In Fig (f) the limit surface in red does not intersect with the cover mesh in blue. It means the cover mesh pletely covers the limit surface. Although this method for the cover mesh is not exact, it is still an applicable way to make a roughcut surface. Of course, we can apply intersection check between the subdivision surface and the cover mesh. Fig. An example of generating cover mesh . Zmap for roughcut surface We then generate a Zmap model for a cover mesh as a roughcut surface by Zmap sampling. For a Zmap model, we set the grid interval for roughcut surface to be half of the cutting allowance , which can be assigned by a user. where R is the radius of a tool. . CL data putation for rough cut The final step for roughcut is to pute the CL (cutter location) data of each slice in order to be imported by a machining controller. After generating the Zmap model for a cover mesh, we slice it layerbylayer perpendicular to the z direction. For each x(or y) constant grid line we define a polyline by sampling the Zmap along this line. Then we find intersection points between the slice plane and the polyline. All these intersection points define CC (cutter contact) points, and then offset by R to pute CL points. By connecting those CL points, an NC cutter path for this grid line is puted. This process is repeated for all the grid lines and also for all slice planes to generate the total roughcut NCcutter path.
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