Interpolation Tolerance

Verifun · 2012-07-19 22:39:55

Ok,

A lot is said about Cut Tolerance and it's effects in the SW performance... but what about Interpolation Tolerance, the 1st field in the tolerances tab?

How much does it influence Vericut's performance... and what exactly depends on it? I read the help and it says:

"Interpolation Tolerance â€” This value is used to interpolate intermediate positions during
NURBS, circular, and helical motions. This tolerance is also used by the Detect 4-Axis
Rotary Motion APT setting to determine if sequential GOTO locations can be performed as
a single 4-axis motion- ref. Project menu > Processing Options > APT Settings: Rotary
tab."

I know it has some effects on circle endpoint calculations... so help me to understand this:

Some CNC controls, like Heidenhains or Sinumeriks for example, will generate a circle endpoint error if the XYZIJK coordinates do not fall within a 0.016mm tolerance (Default value)... so I wonder if in order to make Vericut detect an error like the CNC control would, should we set this Interpolation Tolerance value in Vericut with a value smaller or equal to 0.016mm or the two things are not releated?

What's the impact in terms of performance, in let's say, in a helical cut when this value is tight? What are the recomendations for this value in mm/inches mode?

I just would like to have a clear understanding of this option... if possible with real life examples...

Thanks,

Daniel

Verifun · 2012-07-25 23:22:17

Bump.

MustaphaC · 2012-07-26 22:31:21

Hi Daniel,

You are confusing the tolerance of calculation used to determine circle end points and interpolation tolerance which is used to calculate intermediate points for circles, helical, 5 axes etc..
The tolerance for intermediate points is "Interpolation Tolerance" under File > Property...
The tolerance for circle end points is "Calculation Tolerance" under Configuration > Control Setting...

NOTE: Decreasing "Interpolation Tolerance" will of course affect the simulation speed because more points will be generated. Changing "Calculation Tolerance" will not affect simulation speed

Verifun · 2012-07-27 10:38:21

Hallo Mustapha!

Thanks for you explanation! You are right, I confused the two things...

It's always great to have a formal explanation about functionalities that can affect performance... that's why I always pick your brains because we manufacture large components and performance is definetely an issue for us...

In regards this portion of your statement

circles, helical, 5 axes etc..

, would you mind to elaborate a bit more?

1 - I mean, what is an intermediate point for a circle? Is there any pic or graphical example CGTech could share?
2 - Since helix is a circle with a motion along the tool axis too, what an intermediate point would be in this context?
3 - In 5 axis, will this tolerance have an effect on Auto-Diff results for example?

Sorry for these basic questions but I really would like to have a complete understanding of these topics...

Thank you,

Daniel

Verifun · 2012-08-09 18:02:17

Bump.

VERICUT Users' Forum

#1 2012-07-19 22:39:55

Interpolation Tolerance

#2 2012-07-25 23:22:17

Re: Interpolation Tolerance

#3 2012-07-26 22:31:21

Re: Interpolation Tolerance

#4 2012-07-27 10:38:21

Re: Interpolation Tolerance

#5 2012-08-09 18:02:17

Re: Interpolation Tolerance

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