Be not the computation of coordinate of round curve node

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Should be machined when the interpolation function of appearance of spare parts outline and machine tool is abhorrent, when if be in,spiral of hyperbola, parabola, Archimedes or list curve are being machined on the numerical control machine tool with function of circular arc interpolation point-blank only, be about to use approach law treatment, with linear or circular arc goes approaching by treatment curve. At this moment, approach line segment and by the node of treatment curve, call node. If the graph is shown 1 times, graph A approachs the case of the curve that be not a circle to use straight line segment, graph B is with circular arc paragraph the case that approachs the curve that be not a circle. A) B) graph 1 curve approachs Normal Align=left> composes block, should differentiate by node block. The approximate interval that approachs line segment heals big, criterion node amount heals little, corresponding block amount also can decrease, but the error δ that approachs line segment should is less than or be equal to process designing to allow error δ permit, namely allow of δ ≤ δ . Considering the influence of machining complex and computational error, take the 1/5 ～ 1/10 of spare parts public errand commonly. Normal Align=left> is not spare parts of round curve outline, can undertake by the following measure commonly: Normal Align=left>1) choice interpolation means, be being used namely still is circular arc approachs the curve that be not a circle point-blank. Use straight line segment to approach, general maths processing is simpler, but calculative coordinate data is more, and pointed horn of existence of each joint between straight line segment, because be in pointed part part, cutting tool cannot undertake cutting to the spare parts continuously, spare parts surface can appear hard spot or cut mark, make treatment pledges quantitative change is differred. Use circular arc paragraph imminent way, can reduce the number of block greatly, at the same time if use each other tangent circular arc paragraph will approach the curve that be not a circle, can improve the treatment quality of spare parts surface. But use circular arc paragraph approach, process of its maths processing is a few more complex than wanting point-blank. Normal Align=left>2) affirmatory process designing allows an error, although allow of δ ≤ δ . Normal Align=left>3) choice maths model, determine computational method. The algorithm that in be being produced at present, uses is more, when the decision uses what algorithm, the element of main consideration has two, it is to press the condition that waits for an error as far as possible, determine node coordinate position, so that reduce the number of block to the greastest extent; 2 it is to search a kind of simple calculation method as far as possible, in order to facilitate of computer program make, get node coordinate data in time. Normal Align=left>4) the basis is algorithmic, the picture gives the computer to handle flow chart. Normal Align=left>5) write a program with advanced language, on machine debug, obtain node coordinate data. CNC Milling