topic Re: Circle from three lines in Alias Forum

Circle from three lines

Anonymous — Mon, 26 Mar 2018 08:30:41 GMT

Can i build a circle out of 3 lines.

Re: Circle from three lines

AliasJB — Wed, 28 Mar 2018 17:45:29 GMT

If you mean out of 3 curves, yes you can.

In the Circle options, turn OFF periodic, and you can specify the number of segments, the degree and spans.

3 curve circleCircle options

Re: Circle from three lines

Anonymous — Thu, 29 Mar 2018 06:18:33 GMT

Thank you for the effort.

I wanted to build a Circle which is Tangent to 3 Lines. These lines are in a single Plane. The simplest example would be 3 sides of a square.

Best Regards

Sadat

Re: Circle from three lines

systembolaget — Thu, 29 Mar 2018 15:45:08 GMT

Use AutoCAD for such kind of 2D drafting tasks, then do the 3D model in Alias.

Re: Circle from three lines

Anonymous — Thu, 29 Mar 2018 17:49:05 GMT

Thank you for a replying which is kind of tangent to my query.

And if I have to use AutoCAD for these small things then the whole set of tools in Alias where we have 3 point curve, tangent to curve, perpendicular to curve are just drafting tools which are not supposed to be in Alias. Please raise a ticket to remove those.

The situation is not in 2 dimensions as you are thinking. For the sake of simplicity I explained it in 2D.

When I have 3 surfaces which are like the 3 sides of a cube and I want a fillet which is tangent to all surfaces I have to build a curve and then the surface as Alias is not having any command where i can build it directly by selecting the surfaces.

Thank you.

Re: Circle from three lines

systembolaget — Thu, 29 Mar 2018 18:29:56 GMT

Attach a file so it's possible to understand what you really mean.

The few very basic 2D tools in Alias are certainly not made for drafting. I have never seen anyone outputting an ISO/DIN compliant drawing.

Re: Circle from three lines

Anonymous — Thu, 29 Mar 2018 18:47:19 GMT

I can only attach a sketch of my problem.

If I am unable to clarify the situation then we have to wait till Monday.

Thank you in Advance

Happy Easter

Best Wishes.

Re: Circle from three lines

AliasJB — Thu, 29 Mar 2018 19:27:55 GMT

I suppose in your situation you could use Curves > Keypoint Curves > 3 Point Arc

3 point arc

Re: Circle from three lines

AliasJB — Thu, 29 Mar 2018 19:33:43 GMT

"And if I have to use AutoCAD for these small things then the whole set of tools in Alias where we have 3 point curve, tangent to curve, perpendicular to curve are just drafting tools which are not supposed to be in Alias. Please raise a ticket to remove those."

Now I see that's exactly what you don't want. If your attached surfaces are flat (as they appear to be in the sketch), I think you'll have to hand build it. I don't believe there's an automatic way to do this.

Re: Circle from three lines

systembolaget — Thu, 29 Mar 2018 20:36:38 GMT

If the lines form a square, there is exactly one circle that fits, for each circle can be inscribed into a square; use a circle of the diameter that matches the square's height/width.

If the lines don't form a square, one can solve the algebraic equations or construct it "manually". Draw two lines that bi-sect the angle between two pairs of lines. Where these intersect is the centre of your circle. The radius of the circle is obtained by dropping a perpendicular line from the bisector intersection point as shown.

Greetings from the Easter bunny!

Re: Circle from three lines

Anonymous — Tue, 03 Apr 2018 09:00:54 GMT

3pt curve does not give me the exact Position where it is Tangent.

Re: Circle from three lines

Anonymous — Tue, 03 Apr 2018 09:03:45 GMT

In context 1 it is easy to get Tangent passing through all the sides.

But in Context 2 i cannot do it easily.

Any ways i did it by using ICEM where it can build a circle when we select 3 lines.

Thank You

Re: Circle from three lines

Anonymous — Tue, 03 Apr 2018 11:04:26 GMT

Here i took help from ICEM colleagues to create curves and then imported into Alias.

Thank you

Re: Circle from three lines

duaxiong — Wed, 04 Apr 2018 00:07:39 GMT

Yes...sadly, this is something that Alias has not ever been able to do. It's frustrating when you have a target size that you HAVE to hit. You end up having to put a point on that line...a point you don't necessarily want.

Re: Circle from three lines

systembolaget — Wed, 04 Apr 2018 00:47:42 GMT

Well, you don't have to do anything other than I described to make a circle tangent to three lines in a plane. It's actually very simple. Even in Alias ; )

Re: Circle from three lines

Anonymous — Wed, 04 Apr 2018 14:01:12 GMT

Yes the Suggestion you have is good.

For a given Situation of 3 lines nomatter whether it is a part of a cube or Rhombus or trapezoidal, we are gonna have one circle of certain constant radius Fitting in that Corner for each Situation.

So i suggest Alias can have a single command to achieve this.

The method suggested by Systembolaget, to do bit of construction in 2d is possible.

Thank You