How to Constrain circle with another circle

[ljupadhyay]

Is there any way to constrain a circle with another circle in touch ?

LJU

[Alfredo Medina]

One possible solution is this:

See illustration. The user specifies values for the gap between the concentric circles and for the radius of the outer circle (R). The radius of the inner circle (r) is set to be = R - gap .

[gaby424]

in touch? are they tangent?

then set at their properties to show the centers and put a parameter (name it D) between the centers(tab to snap). Then control bouth radius with two parameters R1 and R2.

In order to keep the tangent conditions you have a formula.

if one circle is in the other one and R1>R2 then D=R1-R2
if one circle is near the other one then D=R1+R2

[Alfredo Medina]

in touch? are they tangent?
...

Good question. The question needs a better description. I understood "in touch" as near, close, but you're right, it might also mean that the circles are touching at one point.

[ljupadhyay]

Yes I have the same problem. If one circle touches at a point to other on it's circumference & need to constrain with that point. Here is an attached which is managed any how

LJU

[Alfredo Medina]

Yes I have the same problem. If one circle touches at a point to other on it's circumference & need to constrain with that point. ...
LJU

In your particular case, you need to determine how much, in proportion, the smaller circle enters into the bigger one. In this example the center of the small circle is separated by a distance equal to 3/4 of the length of the big radius.

The illustration also shows other situations where a small circle is constrained to a bigger circle.

[ljupadhyay]

It means center of a circle can be constrained to a ref. plane. But while constraing I never able to locate the center as it is normaly not visible

LJU

[Munkholm]

It means center of a circle can be constrained to a ref. plane. But while constraing I never able to locate the center as it is normaly not visible

LJU

In that case, you just need to check "Center Mark Visible" at the Circles propertis dialog.
And, having VG set to show "Automatic Dimensions" probably would´nt hurt either in this case.

[ljupadhyay]

Thaks Munkholm
Nice tip I never tried. Now the attache family is currected.

LJU

[patricks]

Whoa, I would not have figured something like that to need to be parametric. Are you planning on using this family in multiple locations with different sizes of the elements?