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Different Curve and Surface types

Different Curve and Surface types

Different Curve and Surface types

I have a question some of you probably know, yet after looking all over for answers I have come up short. What is the difference between Cubic and Quintic curve fit methods? What is the difference between plane and B-surface Free Form Construction Result, and also the Polynomial Cubic Surface? I was having trouble with IGES (go figure) and found that exporting Polynomial cubic seemed to come in cleanest, and I was unable to figure out why, and this leads to me wonder what the differences between curve and surface types are, and the advantages of each. Anyone?


RE: Different Curve and Surface types

It requires a math major to explain it. The basics are that most CAd systems use ther own definition of a spline a nd surfaces. By using NURBS, the math definition is defined by some french mathematician. The different types of splines and such determine the curvature/slope of the resulting geometry.

The higher level curvature will work better in an IGES translation because the formula is now the same on both systems.

DISCLAIMER: I am a mfg engr by degree. I may be totally off the wall on what I said above.

Quiz Time: Define STRESS.

To a mechanical engineer, it is the amount of bending a piece of metal can withstand before reaching its yield limit.
To a manufacturing engineer, it is getting the next MC tape to the shop floor before the current job is finished.

"Wildfires are dangerous, hard to control, and economically catastrophic."

Ben Loosli
CAD/CAM System Analyst

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