Convert HVAC radius elbow to segmented problem..

[danglar]

Hi All!
I need to convert radius elbow to segmented like shown in a picture..
(see attachments)
I find the appropriative routine to convert arc to segmented pline with user defined number of segments
 (see attachments) and now I need a little improvement in this program to draw line or plines from segment vertex’s to center of selected arcs
Can somebody help me to do it?
Any help will be very appreciated

[devitg]

Please upload the dwg , so we have not to redraw it

[danglar]

dwg uploaded (see attachment)

[ВeekeeCZ · Accepted solution]

Nice routine, how about to pay some respect to the author and add the note about where you found it and who is the author?... @_gile probably ??

If you do, he may even to this adjustment for you...

[john.uhden]

Presuming you know the beginning and ending points of the arced segment, 
say P1 and P2, and the Bulge, then...

  (setq Chord (distance P1 P2)
           Sign  (if (minusp Bulge) -1.0 1.0)
           Delta (* 4 (atan (abs Bulge)))
           R     (abs (/ Chord 2 (sin (/ Delta 2))))
           RP   (polar P1 (+ (angle P1 P2) (* (- pi Delta) Sign 0.5)) R)
  )

where R is the radius and RP is the radius point or center of the arc.

Maybe it can be simplified by removing the sign and (abs ...),
but I need to follow my own work, so it usually has extra explicit steps.

[danglar]

Thank you soo much

BeekeeCZ

Your approach work perfect! I really don't know who is the author of main routine, ( I find it in office "storage" place on one of the network disks) but if you sure about @_gile 

I'll pay a great respect to the author and to you too

I appreciate a good work of both of you.

I even published a "final" approach in my blog with respect to both of you. ( see the link)

https://lispbox.wordpress.com/2016/10/18/convert-radius-elbow-to-segmented-with-user-defined-number-...