constructing point at intersection of arcs

[dccfreak]

Hi all,

I am fighting with an issue today and I just can't seem to get myself in the right frame of mind to spend alot of time working through it. I am trying to construct a point at the intersection of a measured arc and a generic arc. Basically, a pitch diameter on a spline and the arc of a tooth. I tried the pierce point option which I use on a family of parts similar to this one but they have flat teeth where this is an involute.

I keep getting the cannot construct error. Any ideas?

Thanks,
Brad

[Wes Cisco]

I know just enough about gears to know I do not know enough to say much. But maybe if you used a generic cylinder instead of a generic arc. . . I think your problem is that the two arc do not actually intersect in "real" 3D space. HTH

[Don Ruggieri]

workarond solution

PC-DMIS does not allow for the intersection of two circles. It does allow for the intersection of a line/circle, but even with that there are two solutions. Here is a series of commands which will get what you want (I think)

Assuming CIR1 and CIR2 do intersect, and lie in the same plane. They do not have to actually be in the same plane, but they need the same normal vector, essentially.

LIN1 =FEAT/LINE,RECT,UNBND
THEO/75,25,7.5,-0.8574929,-0.5144958,0
ACTL/75,25,7.5,-0.8574929,-0.5144958,0
CONSTR/LINE,BF,2D,CIR2,CIR1,,
OUTLIER_REMOVAL/OFF,3
FILTER/OFF,WAVELENGTH=0
PNT1 =FEAT/POINT,RECT
THEO/60.71866,16.4312,7.5,-0.8574929,-0.5144958,0
ACTL/60.71866,16.4312,7.5,-0.8574929,-0.5144958,0
CONSTR/POINT,PIERCE,LIN1,CIR1
LIN2 =FEAT/LINE,RECT,UNBND
THEO/50,10,7.5,0.8574929,0.5144958,0
ACTL/50,10,7.5,0.8574929,0.5144958,0
CONSTR/LINE,BF,2D,CIR1,CIR2,,
OUTLIER_REMOVAL/OFF,3
FILTER/OFF,WAVELENGTH=0
PNT2 =FEAT/POINT,RECT
THEO/59.99387,15.99632,7.5,0.8574929,0.5144958,0
ACTL/59.99387,15.99632,7.5,0.8574929,0.5144958,0
CONSTR/POINT,PIERCE,LIN2,CIR2
PNT3 =FEAT/POINT,RECT
THEO/60.35627,16.21376,7.5,0,0,1
ACTL/60.35627,16.21376,7.5,0,0,1
CONSTR/POINT,MID,PNT1,PNT2
LIN3 =FEAT/LINE,RECT,UNBND
THEO/60.35627,16.21376,7.5,0.5159,-0.8566488,0
ACTL/60.35627,16.21376,7.5,0.5159,-0.8566488,0
CONSTR/LINE,PRTO,LIN1,PNT3,0
PNT4 =FEAT/POINT,RECT
THEO/58.68335,18.99163,7.5,0.5159,-0.8566488,0
ACTL/58.68335,18.99163,7.5,0.5159,-0.8566488,0
CONSTR/POINT,PIERCE,LIN3,CIR1
LIN4 =FEAT/LINE,RECT,UNBND
THEO/60.35627,16.21376,7.5,-0.5159,0.8566488,0
ACTL/60.35627,16.21376,7.5,-0.5159,0.8566488,0
CONSTR/LINE,REV,LIN3,0
PNT5 =FEAT/POINT,RECT
THEO/62.00877,13.46979,7.5,-0.5159,0.8566488,0
ACTL/62.00877,13.46979,7.5,-0.5159,0.8566488,0
CONSTR/POINT,PIERCE,LIN4,CIR1

PNT4 and PNT5 represent the two soultions, where the two circles intersect.

There are certain rules to intersecting a line/circle combination, etc. I leave those out for brevity. Let me know if you have any question on this.