many segments to be reduced in a few arches

[un_poldo]

Hi.
boys, I have a contour of a template to cut to cnc that was imported into rhino by autocad and comes from other 3d software of those who designed the silhouette.

I now find myself having a very small set of segments (lines) that compose the figure and draw its shape in a very defined way.

My problem is that by going through cnc machines a lot of lines it weighs all over me and I would like to decrease these lines.

the optimal would be able to convert these lines into arches, can you tell me if it is possible?

I know that usually the need is the exact opposite, but I find myself having to reduce the number of segments.

 

[Ezio Olivato]

Of course you can do, but an image of your silhouette would be much more explicit.
to assess the technique most appropriate to the case in question.

 

[un_poldo]

then, imagine the shape of a car, only the contour I mean, drawn on a sheet.

Here, instead of having a single line that follows the silouette, I have many small segments oriented in the correct way that trace the shape.

the size of the panel from which to obtain the cut shape is 1500x3000 mm and the shape is little less (it is inside just in the panel). the segments have variable length, from 1 mm to 10 mm, depending on the points of the design.

 

[Ezio Olivato]

try to convert the polyline profile, or generate a contour by clicking inside the profile, and see what comes out.

 

[un_poldo]

What exactly do you mean?
Can you get me the exact procedure with rhino 4?

 

[Ezio Olivato]

then I press that I do not know so well rhino, but if the design you imported it from autocad, you can convert it with autocad; and finally reimport it on rhino once modified.
open it with autocad, highlight only the outer contour of the silhouette and cover it on new file. at this point editpline/unisci and selections all the silhouette. double sending and you got a closed polyline of the profile. expose it to dxf r12 and check the result.
Otherwise there is only the raster procedure that allows you to reconstruct directly with unique polylinea profile, but it is definitely longer!

 

[un_poldo]

does not work this editpline, i.e. it seems to work but leaves the object with all segments.

At most I can join him by "copy/paste as block", but that's not what I care about.

a block not a spline or a set of arches, is however the union of the usual segments.

 

[Ezio Olivato]

It is necessary that the lines be combined, otherwise it does not unite them.
try posting the profile we see how you can do it!

 

[mariuss.r]

Hi.
boys, I have a contour of a template to cut to cnc that was imported into rhino by autocad and comes from other 3d software of those who designed the silhouette.

I now find myself having a very small set of segments (lines) that compose the figure and draw its shape in a very defined way.

My problem is that by going through cnc machines a lot of lines it weighs all over me and I would like to decrease these lines.

the optimal would be able to convert these lines into arches, can you tell me if it is possible?

I know that usually the need is the exact opposite, but I find myself having to reduce the number of segments.

I think all the work you can do in rhino.
I would do that....

1) I would combine all segments in a grade 1. polylinea

2) I would make a copy of that curve on which to work

3) I would apply to the copy of the curve the _fitcrv command that allows to simplify ( reduce the number of points) the curve itself within a given tolerance.

4) I select the two curves (the original one and the transformed one) I would use the _crvdeviation command to verify the maximum deviation between the two curves.

If the result does not satisfy me I would repeat the procedure by giving _fitcrv command of the most restrictive or wider parameters depending on the previous result.

In the attached file you will find the result of this operation, on a polyline that resembles a car shape (green curve), containing 2000 points.
After simplification it turns into a spline (red curve) of about 144 points with a maximum deviation in a very precise point of 0.25 mm.

I hope I have clearly explained the procedure:

 

[vittoriocar]

join the segments so you get a polyline then with the command _rebuild overrides the polylinea in a grade 3 curve then with the command! _convert _pause _output=arcs turn the curve into arches. depending on the tolerances you will set you will get more or less strings.
hi vittorio